ACS Publications. Most Trusted. Most Cited. Most Read
Quality Criteria for the Analysis of Microplastic in Biota Samples: A Critical Review
More

OR SEARCH CITATIONS

My Activity
Publications

Figure 1Loading Img
Download Hi-Res ImageDownload to MS-PowerPointCite This:Environ. Sci. Technol. 2018, 52, 18, 10230-10240
  • Open Access
Critical Review

Quality Criteria for the Analysis of Microplastic in Biota Samples: A Critical Review
Click to copy article linkArticle link copied!

  • Enya Hermsen
    Enya Hermsen
    Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen, The Netherlands
    More by Enya Hermsen
  • Svenja M. Mintenig
    Svenja M. Mintenig
    Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands
    KWR Watercycle Research Institute, Nieuwegein, The Netherlands
    More by Svenja M. Mintenig
  • Ellen Besseling
    Ellen Besseling
    Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen, The Netherlands
    Wageningen Marine Research, IJmuiden, The Netherlands
    More by Ellen Besseling
    Orcidhttp://orcid.org/0000-0003-0686-2173
  • Albert A. Koelmans*
    Albert A. Koelmans
    Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen, The Netherlands
    Wageningen Marine Research, IJmuiden, The Netherlands
    *E-mail: [email protected]
    More by Albert A. Koelmans
    Orcidhttp://orcid.org/0000-0001-7176-4356
Open PDFSupporting Information (1)

Environmental Science & Technology

Cite this: Environ. Sci. Technol. 2018, 52, 18, 10230–10240
Click to copy citationCitation copied!
https://doi.org/10.1021/acs.est.8b01611
Published August 23, 2018

Copyright © 2018 American Chemical Society. This publication is licensed under CC-BY-NC-ND.

Abstract

Click to copy section linkSection link copied!
High Resolution Image
Download MS PowerPoint Slide

Data on ingestion of microplastics by marine biota are quintessential for monitoring and risk assessment of microplastics in the environment. Current studies, however, portray a wide spread in results on the occurrence of microplastic ingestion, highlighting a lack of comparability of results, which might be attributed to a lack of standardization of methods. We critically review and evaluate recent microplastic ingestion studies in aquatic biota, propose a quality assessment method for such studies, and apply the assessment method to the reviewed studies. The quality assessment method uses ten criteria: sampling method and strategy, sample size, sample processing and storage, laboratory preparation, clean air conditions, negative controls, positive controls, target component, sample (pre)treatment, and polymer identification. The results of this quality assessment show a dire need for stricter quality assurance in microplastic ingestion studies. On average, studies score 8.0 out of 20 points for “completeness of information” and 0 for “reliability”. Alongside the assessment method, a standardized protocol for detecting microplastic in biota samples incorporating these criteria is provided.

Copyright © 2018 American Chemical Society

Subjects

what are subjects

Introduction

Click to copy section linkSection link copied!
The ubiquity of microplastic (plastic particles < 5 mm (1)), combined with associated effects, has raised concerns regarding marine species, ecosystems, and the impact it may have on human health. Microplastics have been detected in a wide variety of habitats in the ocean from shallow coasts to the deep sea. (2−4) Increasing numbers of studies report the ingestion of microplastic by marine biota across multiple trophic levels, including animals often targeted by fisheries (Table 1). (5−9) The ingestion of microplastics seemingly concerns a wider range of species than the ingestion of meso- and macroplastics; indeed, it is considered the most frequent interaction between plastic debris and marine organisms. (10)
Table 1. Scoring of the Reviewed Articles in the Current Quality Assessmenta
  criterion
  12345678910 
studyyearsampling methodssample sizesample processing and storagelaboratory preparationclean air conditionsnegative controlpositive controltarget componentsample treatmentpolymer identificationaccumulated score
Lusher et al. (48)2016222212022015
Tanaka and Takada (78)2016222001022213
Davidson and Dudas (59)2016112202220012
Rummel et al. (58)2016220212001212
Courtene-Jones et al. (49)2017002201022211
Devriese et al. (56)2015212022020011
Mathalon and Hill (8)2014112112120011
Wesch et al. (79)2016022020022111
Cannon et al. (43)2016022020020210
Desforges and Galbraith (50)2015222002020010
Li et al. (80)2016220001120210
Murphy et al. (81)2017210201020210
Vandermeersch et al. (27)2015112022020010
Davison and Asch (41)201122200120009
Foekema et al. (6),b201322100002209
Karlsson et al. (53)201711210202009
Nadal et al. (82)201622220100009
Torre et al. (54)201602221200009
Bellas et al. (47)201621210100108
Jabeen et al. (44)201602010102028
Lusher et al. (5)201322200000028
Van Cauwenberghe et al. (60)201410102202008
Brate et al. (83)201602020100027
Anastasopoulou et al. (84)201302200002006
Besseling et al. (16),b201520000000226
Jantz et al. (85)201312200000106
Murray and Cowie (51)201122200000006
Peters et al. (70)201712200100006
Vendel et al. (86)201722100000005
Boerger et al. (52)201022000000004
Liboiron et al. (55)201602000002004
Neves et al. (7)201500100000023
Wojcik-Fudalewska et al. (87)201601200000003
Romeo et al. (9)201511000000002
Miranda and de Carvalho-Souza (88)201600000000000
Av all-study score (n = 35) 1.141.461.310.570.400.860.171.030.430.668.0
a

Scores of 0–2 were assigned to each publication in each of the 10 categories. The publications are sorted from high to low based on the “accumulated score”. The overall reliability score was 0 for all studies and is not indicated.

b

Studies with involvement of 1 or more of the authors of the present paper.

Ingested microplastic particles are thought able to evoke a biological response through both physical and chemical mechanisms, although many of these effects have yet to be studied. Ingestion of microplastics is thought to cause physical damage in small organisms (2) and has been speculated to provide a pathway for some associated chemicals to enter and spread in the food web all the way up to humans with microplastic particles as vectors. (11−13) Additionally, ingestion by biota is considered a possible sink for microplastics. (14) Therefore, measuring quantities of ingested plastic is of high priority to properly assess the risk of such hazards.
Physical impacts for small organisms like internal abrasions and blockages have been reported. (2) Moreover, microplastic particles were shown to cause damage leading to cellular necrosis, inflammation, and lacerations of tissues in gastrointestinal tracts according to a review of plastic impact on biota. (15) In bigger organisms, ingestion of larger objects (i.e., macroplastics) has been demonstrated too. (16,17)
In addition to the impact of ingested microplastics proper, persistent organic pollutants (POPs) may concentrate on the particles. It is suggested this could pose a possible new route for POPs to enter the food chain; (11,12) however, it has not been irrefutably shown that this actually happens. (18−20) Contrarily, evidence in Northern Fulmars (Fulmarus glacialis) suggests a transfer of POPs from the lipids in the animal to the plastic rather than the other way around. (18)
The concerns for the impacts of microplastic are reinforced by the hypothesis that microplastics may be able to spread through the food web by means of trophic transfer, a phenomenon that has been observed in a few instances. (21,22) This is cause for concern especially in commercially valuable species as it possibly poses a threat to human food safety. (23) To what extent this transfer occurs in the food web remains to be studied further.
Despite these worries concerning microplastic ingestion, the effects in the natural environment and implications for the food web remain poorly understood. Because of the absence of suitable standardized methods, data are too often incomparable, are not representative, and lack quality assurance. (24−28) Hence, our knowledge on the fate and impacts of microplastics remains incomplete. The microplastic research field is young, and as research performed now lays down the foundations for later studies, there is a dire need for a standardized protocol for carrying out studies on the ingestion of microplastics by marine biota to mitigate this issue. (27) Although first steps toward standardization of methodologies in environmental samples are being made, (27,28) the comparability of current data is being impeded by the wide variety of methodologies, which has led to data of different quality. (24,29) For dealing with the wide spread in quality of the data produced by studies, an example can be taken from the field of toxicology. In toxicology, it is common practice to assess the reliability of studies with consensus criteria, like the so-called Klimisch score, (30) or the recently proposed Criteria for Reporting and Evaluating Ecotoxicity Data (CRED). (31) These methods both offer scoring systems with different reliability categories, generating standardized documentation of validity evaluation. They were developed to guide risk assessors in performing unbiased, transparent, and detailed evaluations while guiding researchers in performing and reporting studies in a manner deemed appropriate. (31) We argue that research and risk assessment with respect to the impacts of plastic debris are in urgent need for the development and use of such criteria. (32)
The aim of the present study is to critically review the literature on ingestion of microplastic by marine biota. On the basis of this review, we develop a scoring method for ecological studies and the analytical methodologies employed to detect plastic debris in aquatic biota samples. The scoring method is subsequently applied retrospectively to the reviewed studies. This assessment does not result in an absolute judgment but is an indicator of the usefulness of these studies for risk assessment and monitoring purposes of microplastic ingestion in natural populations. We also provide average scores per evaluation criterion, illustrating which methodological aspects need improvements most. Finally, our synthesis provides the basis for a quality assurance protocol for the analysis of microplastic debris in biota samples.

Materials and Methods

Click to copy section linkSection link copied!
An extensive literature review was undertaken by accessing the Web of Science, ScienceDirect, and Scopus databases for studies of microplastic ingestion in marine biota in natural populations, including studies from all years up until those published in June 2017. Queries included the following search terms: “microplastic AND ingestion AND marine”, “microplastic AND uptake AND marine”, “microplastic AND marine biota”, and “microplastic AND biota AND monitor*”. Reference lists of the found articles, reviews, and “reversed searches” were consulted as well, resulting in a representative collection of 35 currently available studies. Laboratory exposure experiments were excluded from the collection. Furthermore, studies were only included if they provided data on the ingestion of microplastic. For these studies, the ingestion incidence was calculated as the fraction of sampled individuals containing microplastic. The 95% confidence intervals for these binominal proportions were assessed using the Wilson method. (33) Subsequently, studies were scored according to method quality criteria discussed in the next section. All studies were assessed by two separate authors independently, after which differences in scoring were discussed and tuned until the assessment was done consistently across all studies. For maximizing transparency and traceability, the scoring explanations, scoring criteria, and scorings for all papers are provided as Supporting Information (Tables S1–S3, respectively). The eventual assessments do not express the value of studies. In hindsight, they only reflect the compliance of studies to reliability criteria as perceived by the authors of the present paper. Although we maximized our effort to be complete and thorough in this process, misinterpretations or misjudgements cannot be completely excluded.
The scoring method presented here was designed to assess current studies on reliability of their data on microplastic ingestion in marine field biota and is based on several aspects that define a reproducible and controlled study. The method evaluates the inherent adequacy of the employed methods for monitoring and risk assessment purposes relating to a standardized methodology and the description of the procedure and results. By scoring high in all categories, a study can be defined as “reliable”, providing reproducibility, clarity, and plausibility of its findings.

Quality Assessment System

Click to copy section linkSection link copied!
Previous scoring systems that have been proposed for assessing the reliability of ecotoxicology studies are the Klimisch (30) and the more recent CRED scoring systems. (31) The Klimisch criteria have received critiques for being unspecific and for lacking essential criteria and guidance, leaving too much room for interpretation. (31) The CRED evaluation method gives extensive guidance on how to use the set criteria and gives recommendations for reporting. (31) Following the example set by the CRED method, the present evaluation method for microplastic ingestion studies provides several criteria that must be assessed, including guidance on how to assess each criterion. The quality assessment method is made up of ten criteria: (1) sampling method and strategy, (2) sample size, (3) sample processing and storage, (4) laboratory preparation, (5) clean air conditions, (6) negative controls, (7) positive controls, (8) target component, (9) sample (pre)treatment, and (10) polymer identification (Table 1). For each criterion, a score of 0, 1, or 2 can be assigned to the publication under review. Scores signify the following: 2 = reliable without restrictions, 1 = somewhat reliable but with restrictions, 0 = not reliable. If information is lacking on certain aspects in the publication, this is considered unreliable, leading to a lower score. After each criterion is scored, an overall reliability score is calculated by taking the product of all criteria scores, resulting in a maximum attainable overall theoretical reliability score of 1024 points, indicating a high reliability of a publication. This contrasts with both the CRED and Klimisch method: these methods assign a category of reliability to each criterion but do not quantify it with a score. (30,31) In the evaluation method presented here, the quantification through scoring is deemed important because each criterion is considered crucial and equally important to the reliability of the results of a study. This means when a study scores 0 points on a criterion, too much uncertainty still surrounds the results of the study, marking the results unreliable. This also means that when only one criterion is evaluated as “not reliable” (0 points) the overall reliability score of the study will be 0. Besides this overall reliability score, we provide an accumulated score calculated as the sum of the individual scores. This score has a maximum of 20 points and can be seen as a combination of the reliability and the completeness of information in a publication.
In the following ten paragraphs, argumentation is provided on each of the ten scoring categories, including explanation based on the currently reviewed studies and specification of scoring criteria. A supporting, more detailed overview of the scoring criteria is provided as Supporting Information (Tables S1 and S2).

Sampling Methods and Strategy

Several factors related to sampling method and strategy affect the results of microplastic detection in biota samples. For instance, because of differences in density and sinking as a result of biofouling, plastic is found at different depths of the water column. (10,34) Microplastics are also known to accumulate in the sediment (28,35,36) with deep sea bottoms likely to make up a sink for the particles. (34,37,38) It is plausible that feeding strategy has an influence on the type and amount of microplastic ingested (39,40) with planktivorous and filter feeders expected to be more susceptible to ingestion of low density particles floating in the top layers of the water column and demersal and bottom dwelling species more likely to encounter high density microplastics. Additionally, some species are known for diurnal vertical migration and are subjected to a wide variety of microplastic encountered, possibly affecting their ingestion rates. Nonecological factors such as mesh size will influence life stage of the caught individuals in the sample, whereas a small mesh size could lead to cod-end feeding. (41) Sampling methods can greatly influence the outcome of a study; therefore, it is important that such characteristics of the sampling are recorded to create a reproducible study. (28,42) Furthermore, by reporting such details, it could be easier to interpret the outcome and account for possible contamination in the results.
In this section, studies are scored on reportage, and therefore reproducibility, of the sampling, but also on choice of sampling method itself. Studies scoring high in this section reported extensively on their methods (e.g., type of gear, sampling location and depth) and controlled their own sampling or were fully aware of what had happened to the specimens during sampling. Articles with low scores either failed to report on (parts of) their sampling (Table 2), or used, for instance, store-bought individuals when making inferences on natural populations. (43,44) The use of store- or market-bought individuals is not inherently wrong as long as the interest of the study lies on contamination of sea food and not on natural populations. Scores of 1 indicate that, for part of the sample, sampling was not performed correctly, whereas for another part of the sample it was: the aim of the study should be correctly matched to the sampling method. For example, Vandermeersch et al. (2015) (27) partially used store-bought individuals while using self-sampled ones for a different part of the study. The microplastic uptake in mussels from different estuaries was compared with the uptake by commercial mussels. The commercial mussels were bought in stores, leading to uncertainty about the treatment of these mussels prior to the analysis: microplastic found in these mussels could have originated from contamination during handling in the production chain rather than from microplastic ingestion by the mussels themselves. Would the aim of this study have been to check microplastic content in store-bought individuals (i.e., checking on general contamination, not ingestion), this would not have been an issue. This study scored 1 in this section because part of the study can be considered reliable with sampling method correctly matched to the aim of the specific part of the study.
Table 2. Standardized Protocol for the Detection of Ingested Microplastic in (Marine) Biota
1. Sampling methodsSampling characteristics that should be recorded:
- Gear
- Mesh size and mesh size at cod-end (if applicable)
- Material
- Location
- Depth
- Date and time of day
- Presence of plastic materials
2. Sample sizeA suitable sample size of 50 individuals per research unit (species, food web, ecoregion, feeding type, etc.) is required. (42,45)
The confidence interval of the ingestion incidences should be reported (Figure 1).
3. Sample processing and storageBetween the moment of capture and the examination in the lab the biota samples should be stored on ice or frozen at −20 °C. Smaller organisms can also be preserved in a glass container with ethanol or formaldehyde. Any sample handling, such as dissections, should be left for the lab.
4. Laboratory preparationAll materials, equipment, and laboratory surfaces need to be thoroughly washed and rinsed; afterward, all materials should be kept under clean air conditions. Used solutions and filters should be checked before use; the same applies for the outside of the sample specimens. (6)
5. Clean air conditionsThe handling of samples should be performed in clean air facilities. (28) Samples should not be taken out of the clean air facilities without being sealed off. If sampling processing and analysis cannot fully be conducted under clean air conditions, the implementation of negative controls (see criterion 6) will get even more important.
6. Negative controlA replicate of 3 negative controls is advised that are included for each batch of samples and treated in parallel to the sample treatment. (42)
Additionally, if the samples have to be analyzed outside of the clean air facilities, clean Petri dishes should be placed next to the sample, and checked for any occurred air- borne contamination.
7. Positive controlsA replicate of 3 is advised in which microplastics of known polymer identity and of targeted sizes are added to “clean” samples, which are then treated and analyzed the same way as the actual samples. The particle recoveries are calculated by tallying the numbers of retrieved particles to the amounts added.
8. Target componentTo ensure monitoring all ingested microplastic, the full gastrointestinal tract (esophagus to vent) of fish and the entire body of smaller species, e.g. bivalves, should be examined.
9. Sample treatmentA digestion step must be included to dissolve organic matter in the sample when aiming in the detection of small microplastics (<300 μm). The digestion method described by Foekema et al. (2013) (6) using a 10% KOH solution and enzymatic digestion methods (yet only for small organisms) are most suitable. (49,61,65) In any case, heating or drying of the samples at high temperatures should be avoided.
10. Polymer identificationUntil now, most common methods in the field of microplastic research are FTIR or Raman spectroscopy, pyrolysis or TGA- GC-MS. The polymer identification is required for all, or at least a subsample of particles: When numbers of pre- sorted particles are <100, all particles should be analyzed. For particle numbers >100, >50% should be identified with a minimum of 100 particles. Particle counts with confidence intervals, detection limits for the count and for minimum particle size, polymer types and percentages (of different polymer types, of synthetic vs natural material), and particle sizes should be reported.

Sample Size

Both the International Council for the Exploration of the Sea ICES (2015) (42) and the European Strategy Framework Directive’s Technical Subgroup on Marine Litter (MSFD-TSGML) (2013) (45) recommend a sample size of at least 50 individuals. This sample size of 50 is arbitrarily chosen, since, due to the wide variety in microplastic ingestion reported by different studies, no clear indication of the true ingestion incidence of microplastic by biota can be estimated. When more clarity can be given in the future, this recommended sample size should be adjusted accordingly. If ingestion incidence appears to be low, higher sample sizes will be needed to give reliable results; if populations show high incidence of microplastic ingestion, lower sample sizes will suffice.
The scoring in this category is fairly straightforward using the recommended 50 individuals as a threshold until it is possible to perform a reliable power analysis to calculate a more appropriate sample size for ingestion studies. Too low a sample size may provide interesting data, but no conclusions should be drawn as the statistical power of such a study would be simply too low to infer any trends. A larger sample size is always advisible because it will lead to more reliable results, i.e., narrower confidence intervals (Figure 1). Studies with a sample size over 50 specimens taken from a food web or ecoregion scored 2. A score of 0 was ascribed to studies using less than 50 specimens. Studies with >50 specimens in total and >25 specimens per research unit (e.g., a species, food web, or ecoregion) received a score of 1. For now, we also applied these criteria to a study that reported the presence of microplastic in a single-stranded whale, (16) leading to a very wide confidence interval (Figure 1). However, for whales or for rare and protected species, the n = 50 criterion is difficult or even unethical to achieve in a sampling effort meant to assess trends in microplastic ingestion. For such big or protected organisms, retrospective data obtained from stranded animals and from bycatch through different reports need to be combined to reach a sample size with sufficient rigor. (17) This would require harmonization of protocols to increase comparability of studies, guidance for which is beyond scope of the current review.

Figure 1

Figure 1. Ingestion incidence and 95% confidence intervals recalculated from data provided in microplastic ingestion studies. Data are combined to obtain a “whole ocean” biota ingestion incidence value (○).

High Resolution Image
Download MS PowerPoint Slide
We further advise provision of the confidence interval in the reported count (e.g., refs (5and46)); however, this was not yet included as criterion in the current scoring. On the basis of the total number of animals and the number of animals that ingested microplastics, we calculated the confidence intervals and provide an overview in Figure 1.

Sample Processing and Storage

After sampling, samples need to be stored until examination in the laboratory. Samples are often frozen, (5,9,47,48) or whole specimens of smaller species are preserved in fixatives such as formalin, ethanol, or formaldehyde. (49−53) ICES (2015) (42) recommends storing biota samples on board using aluminum foil for freezing at −20 °C or preservation in ethanol in glass containers. In the present study, it was not considered necessary to wrap each individual in aluminum foil as long as specimens were quickly frozen after capture at −20 °C and stored in a closed container. If this is combined with a pre-examination rinse of the specimens (see “laboratory preparation”), it should suffice in mediating contamination of the exterior of the specimen. Under no circumstance should the specimen be opened on board. This is considered as a high and difficult to assess risk for contamination due to unregulated conditions on board. We further recommend avoiding the dissection of individuals outside clean air conditions at all times (see “clean air conditions”).
High scores were assigned to studies freezing their samples shortly after capture at −20 °C or storing them on ice, leaving any further handling until the laboratory. Alternative methods storing the samples in closed off containers with a fixative were also given the highest scores in case potential effects of these chemicals on different plastics were studied before application. Recently, the resistance of microplastics to formaldehyde/ethanol has been confirmed. (49) Studies scoring low in this section performed dissections, or otherwise opened the specimens, on board. Middle scores again indicate some aspects of the study do not comply but still partially meet the standards (e.g., different processing for different subsamples).

Laboratory Preparation

Contamination is a prevalent issue in microplastic research, creating uncertainty around the results of many studies. (27,28,54) This risk and uncertainty have been dealt with in different ways. Different forms of prevention have been applied with varying degrees of success. Foekema et al. (2013) (6) decided to exclude small fibers from analyses after finding a sharply decreased abundance when working under clean air conditions. ICES (2015) (42) proposed in their preliminary protocol to exclude all fibers smaller than 5 mm in length from results. Although this may provide a way to reduce the issue of contamination in results, it is less than ideal; by excluding all small fibers from results, truly ingested fibers will be excluded from the results too. This could lead to an underestimation of ingestion rates and a potential knowledge gap in the ingestion of microplastic. Therefore, proper prevention is needed. In the laboratory, contaminations with synthetic polymers should be avoided as they may influence ingestion results. (6,27) Equipment, tools, and work surfaces should be free of particles to avoid easy contamination. To this end, all materials used should be washed and rinsed thoroughly with high quality water (e.g., Milli-Q water) before use and preferably kept in a clean air cabinet.
Factors such as clothing should be considered. Often, contamination arises in the form of microfibers. (27,28) Additional contamination originating from researchers’ clothing can easily be avoided by solely wearing 100% natural fiber clothing, such as cotton. Only wearing a 100% cotton lab coat may not suffice; if one was to wear a polyester shirt underneath, it would not be unimaginable that some fibers could end up in the samples. For the current scoring in this study, if all other precautions were met, a 100% cotton lab coat was considered sufficient.
In some studies, precautions were made by wiping surfaces and tools using alcohol. (55) This method is probably not thorough enough to deal with contamination; merely wiping surfaces, be it with alcohol or water, could still leave particles. They could be missed, detach from the wipe during wiping, or the wipe itself could even prove to be a source of contamination (i.e., the material or dust already collected on the wipe before use). Rigorously washing and rinsing of the equipment are considered to be the only proper option here.
Additional to the preparation of surfaces and tools, the sample specimens themselves require some preparation. The exterior of the animal should be rinsed (6,46) and checked for contamination. In the case of small specimens such as zooplankton, this is not an easy feat. In a study performed by Desforges et al. (2015), (50) this issue was overcome by individually checking each specimen under a microscope and picking off any external contamination with a pair of tweezers.
In summary, a score of 2 was assigned when nonsynthetic clothing and a lab coat were used and equipment and organism exterior were rinsed. A score of 1 was assigned for solely wiping laboratory surfaces and equipment or not wearing a lab coat as long as negative control samples were run in parallel and examined for contamination. A score of 0 was assigned when no precautions were met.

Clean Air Conditions

Problems with airborne contamination are unavoidable unless work is performed under clean air conditions. (6,27,28) To this end, sample handling should be done in a laminar flow cabinet (42,46,56) or in a “clean room”, which is designed to minimize airborne contamination during sample handling and analysis. (28,57) The use of such facilities is a necessity in microplastic research; any handling of samples outside clean air conditions creates a high risk of airborne contamination. (57)
Other studies placed their samples in a fume hood to minimize the risk of contamination. (56) However, because a fume hood draws air from the room into the hood (contrarily to a positive pressure laminar flow cabinet, which blows filtered air through the cabinet into the room), the risk of airborne contamination remains. (57)
A few studies were seen that mitigated contamination by closing off samples as much as possible and handling them as fast as possible. (44,53) These methods are not foolproof and should not be relied upon without further indication on results of negative samples treated in parallel to actual samples.
The proper use of clean air conditions was given a score of 2. A score of 0 was assigned to studies taking no regard for airborne contamination. Studies mitigating contamination by carefully keeping samples in a closed off situation as much possible scored 1 in this category, provided that negative controls were run in parallel and examined for contamination.

Negative Controls

Although increasing in recent studies, the use of controls in microplastic research is not standard practice. During sample handling, the chances of contamination by microplastic particles and fibers are high; thus, the use of controls, treated and analyzed in parallel to actual samples, is crucial.
For a study to score 2, proper blanks should be included for each batch of samples with at least three replicate blanks per batch. These controls should be performed without tissue, or with tissue that was confirmed to be devoid of microplastic, in parallel with samples containing the target component. (42,58) By doing so, the controls are given the same full treatment as the studied specimens. Controls should be run regularly and with special attention to moments of high risk of contamination, such as moving specimens in and out of the laminar flow cabinet. (29) Furthermore, the visual examination of samples forms a moment of high risk, which is why additionally placed and examined Petri dishes next to the sample might be advisible. (46)
Scores of 1 indicate a blank analysis of some form, nevertheless deemed insufficient here. This includes, for instance, solely open Petri dishes or soaked paper that were placed next to the work surface and checked for contamination (46,48) or the filtration of air. These do not account for contamination derived from used chemicals or equipment. Studies scored 0 when no form of negative control was included in the study.

Positive Controls

It is generally difficult to assess whether all microplastics present in a sample are effectively recovered from that sample. Small particles in particular may be overlooked or missed, and losses may occur during all steps of sample preparation, processing, and analysis. Therefore, it is considered crucial to include controls (triplicate) with added microplastic particles that are treated in parallel to the samples to determine the recovery rate (score of 2 points). Ideally, positive controls should also be included for the smallest targeted size class, and the limit in the detected size should be reported. We are aware of only three studies that included reliable positive controls. (41,46,59) Davison and Asch, for instance, (41) blindly added random numbers of spherical beads from two size classes into fish stomach contents, so that the researcher would not know this number, and were able to trace back all added particles to achieve 100% recovery. A score of 1 was assigned to studies with some form of a positive control (e.g., testing only a part of the protocol), and a score of 0 was assigned when no positive controls were included.

Target Component

Among the reviewed studies, different target components were described that are mainly (parts of) the digestive tracts for larger biota, like fish, (5,6,9,46,52) or whole specimens for smaller species, like bivalves (27,50,60) Choosing a suitable target component is an important part of the study setup. For accurate estimation of microplastic ingestion, it is important to examine the entire gastrointestinal tract (GIT) (esophagus to vent). By only examining the stomach, particles in the gut would be missed, leading to an underestimation of ingestion rate. When small animals such as bivalves and zooplankton are being studied, the entire specimen should be used.
Studies examining full specimens or entire GITs received the highest score. Examination of parts of the GIT were scored lowest. In case a study examined a part of the GIT for a subsample yet full GITs for the rest of the sample, it was scored 1.

Sample (Pre)treatment

For extracting and characterizing microplastics in biological samples, a digestion step is a crucial component, namely, dissolving organic matter without degrading plastic polymers. Detection of microplastic in a biological sample without getting rid of the organic matter makes for an unreliable method; the chance of missing particles is high, especially small particles that are not visually detectable. (27) Therefore, it is advised to make use of a digestion pretreatment. (42,61)
Dehaut et al. (2016) (62) performed a study testing six existing methods (including enzymatic, alkaline, and acidic digestion), comparing their effects on 15 different plastic polymers as well as their efficiency in biological samples. Their tests showed that, out of the six protocols, an adapted protocol of Foekema et al. (2013) (6) was most successful. The original protocol involves the samples being left for digestion in 10% KOH solution and kept at room temperature for 3 weeks. The adapted protocol used 10% KOH solution with 24 h of incubation at 60 °C. (62) This adaptation was made to shorten the incubation time. The heating of samples during digestion pretreatments to speed up the process is fairly common, and especially with acidic digestion methods, this is often part of the protocol. However, this practice may be ill advised because the heating of the samples could cause some microplastic particles to deform or clump together. (63) Therefore, it is advised to apply the original protocol of Foekema et al. (2013). (6) The adequacy of the 10% KOH protocol has recently been confirmed by Kühn et al. (2017) (64) and Munno et al. (2018). (63) However, for smaller organisms, like the soft tissue of mussels or plankton species, enzymatic methods have also been shown to provide high digestion rates with no damage to microplastic. (65,66)
On the basis of these findings, studies using a 10% KOH solution-based digestion, or an enzymatic digestion, received the highest score of 2. Studies not incorporating a digestion step received no points. Studies using other digestion methods were scored 1. A score of 1 was also assigned to studies that did not need a digestion step because the size of particles was large enough, which can be achieved by sieving the samples over 300 μm. This mesh size allows adequate particle sorting as is done frequently for, e.g., water samples. (67−69)

Polymer Identification

Accurate identification of polymer types in environmental samples can be laborious. Hence, two aspects are relevant when assessing the polymer identities of a microplastic sample: (1) the quality of the method used for the identification (efficiency, sensitivity, accuracy, reproducibility) and (2) the quality of the selection of the subsample (representativeness).

Polymer Identity

Visual inspection (i.e., characterizing microplastic by eye under a dissection or stereomicroscope) was found to be a frequently used identification method. (8,9,47,50,56,58,70) However, visual examination cannot be used to identify the (polymer) identity of a particle. Without formal evidence of polymer identity, a particle cannot be reported as being a microplastic particle. The quality of visual examination is influenced by the observer, properties of the plastic, targeted microplastic size, magnification of the microscope, and sample type. (28) In a case study on microplastics in North Sea sediments, the usage of focal plane array (FPA) micro-Fourier transform infrared (micro-FTIR) spectroscopy revealed that only 1.4% of the particles visually sorted as microplastic were actually synthetic polymers. (29) Fibers with a size over 500 μm were found to be of natural origin after an initial selection as microplastic. (28,71) This uncertainty of visual identification further increases as particle size decreases, which illustrates the importance of verifying the chemical origin of potential microplastics.
To date, potential microplastics are identified mostly using spectroscopic (29,69,72) or thermal degradation analyses. (73−75) Particles sorted manually are mostly analyzed using attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy, (49,58) but pyrolysis GC-MS is also applied. (73) Both techniques result in a clear identification but are restricted to bigger particles due to the manual particle handling. When aiming for microscopic particle determination, the coupling of a microscope to FTIR or Raman spectroscopy reveals the chemical identity of particles and allows particle sizes to be estimated. Both techniques are limited by a certain minimum particle size. (72,76,77) Alternatively, unsorted samples, i.e., where a polymer mixture might be present, can be analyzed using thermal degradation techniques. (74,75) Because particles are not sorted manually, these techniques are not limited by a minimum particle size required; however, they do not provide information on microplastic size either. Furthermore, they do provide information on ingested polymer masses instead of presenting the numbers of ingested microplastic particles. One of these techniques should be applied and should always be favored over the so-called “hot point-test” applied by several studies. (27,42,56) Plastic particles are “identified” when a particle shows a sticky dark mark when touched with a hot needle. However, this test does not allow polymer identification, is less suitable for thermoset and smaller plastics, and should therefore only be seen as a facilitation for visual sorting.

Representative Subsample of Particles

Many studies report polymer identities for a small subset of sorted particles only. (6,53) This leaves considerable uncertainty with respect to the actual distribution of polymer types among samples. On the basis of practical experience using ATR-FTIR to determine polymer identities, (6,16,46) we advise that when numbers of presorted particles are <100, all particles should be analyzed. For particle numbers >100, analysis becomes more laborious, but >50% should be identified for a representative subsample with a minimum of 100 particles being analyzed. The information given in the results section should contain the following: particle counts with confidence intervals, detection limits for the count and for minimum particle size, the polymer types determined, their percentages with regard to other polymer types and natural particles, and the microplastic size (classes).
If a study identified polymer identities and applied the latter criteria, 2 points were assigned. For insufficient numbers of identified particles that could result in an unrepresentative subsample, 1 point was assigned. Zero points were given if no polymer identification (i.e., purely visual sorting) was conducted.

Protocol for Microplastic Ingestion Studies in Biota

Click to copy section linkSection link copied!
In this article, as a synthesis of our review and method assessment, we propose a standardized protocol for the detection of ingested microplastic in (marine) biota alongside the quality assessment method (Table 2). The protocol is adaptable for both vertebrates and invertebrates as long as the components of the quality assessment system are upheld. The protocol was developed taking the recommended protocol by ICES (2015) (42) into account and amending with knowledge and evaluation of currently existing methodologies as outlined above. The protocol and quality assessment system are such that, when following the protocol successfully, high reliability scores can be acquired. This protocol relies on the same literature analysis and argumentation as the assessment method and follows the categories step-by-step.

General Discussion

Click to copy section linkSection link copied!
Considerable uncertainty with respect to methodology was observed and quantified via the scoring system. Accumulated reliability scores ranged from 0 to 15 out of a maximum of 20 with an average of 8.0 (Table 1). As mentioned before, the results of such an assessment are not an absolute judgment, and the results should not be used as a ranking list of the value of studies. The scores are an indicator of the usefulness of these studies for risk assessment and monitoring purposes with respect to natural populations. The assessment evaluates common characteristics of a variety of studies. Not all decisions in a study can be captured in the scoring system; therefore, it is still important to critically look at a study and reflect upon its plausibility and comparability to other studies and not just upon its results.
Often studies could not be assigned a high score due to missing information on certain characteristics, such as details of the sampling or analytical procedures. Average scores (n = 35) per evaluation criterion were especially low (<1) for the criterion “positive controls” (0.17), “clean air conditions” (0.40), “sample treatment” (0.43), “laboratory preparation” (0.57), “polymer identification” (0.66), and “negative controls” (0.86) (Table 1). By leaving out such essential information, a study immediately becomes irreproducible and thus less reliable. One reason for initiating the present review was to systematically define this crucial information, such that future studies can avoid this by using standardized consensus methods.
On the basis of the assessment of reviewed papers (considered representative for currently available knowledge, Table S3), we conclude that all reviewed studies are not fully reliable. All studies scored 0 in at least one category, indicating an uncertainty around at least one of its aspects. Therefore, the overall reliability scores, calculated as the product of individual scores, were all 0 and thus were not included in Table 1. Each category of the assessment was defined by the consideration that if its set criteria were not up to par, the possibility of contamination could not be excluded. This is problematic, and for future studies the use of the proposed protocol is strongly recommended to obtain reliable and reproducible results. Following the proposed protocol, we conducted a study focusing on microplastic detection in North Sea fish while giving special attention to quality assurance and full reportage. (46)
Our meta-analysis of microplastic ingestion data shows a wide variability among studies, which may be due to methodological, ecological, and/or spatial differences. Ingestion incidence ranges from 0 to 100% with confidence intervals that are narrower for higher sample sizes (Figure 1). On the basis of pooled data from all studies, an overall biota ingestion incidence of 16.6% (15.9–17.2 95% CI) was calculated. This “whole ocean” value can be interpreted as the percentage of the 13722 biota individuals sampled across all oceans in which microplastic was detected in the period of 2010–2017. The data underlying Figure 1 further reveal that, with sample sizes lower than 50, the confidence intervals can become as wide as 35–80% (Figure 1).

Perspective and Outlook

Click to copy section linkSection link copied!
We provided an evaluation method for the quality of studies reporting microplastic ingestion by biota. The applied quality criteria were defined based on a critical review of the literature available. Current studies are not of such a level of reliability that they could be used confidently for risk assessment or monitoring of microplastic by biota in the natural environment. Reliable ingestion rate studies are needed to define whether there is a risk posed by microplastic ingestion to the natural environment and to human food-safety. The proposed protocol can be used to perform these studies; the quality assessment system can be applied to control the quality of these data and enable an easier comparison of studies to move toward standardization and reliability. The quality assessment system may provide a tool and set an example that will help regulators and policy makers in their activities to mitigate contamination with plastic debris. Until now, the majority of studies focused on visually sortable microplastics. Our present scoring system is tuned to this research aim and used today’s best available information. However, we foresee that our recommendations may need adaptations when the focus is on much smaller microplastic, which is more difficult to detect. It is also conceivable that our proposed scoring system needs modification if the research field evolves, for instance, when new analytical technologies become available, just like the aforementioned CRED criteria (31) can be seen as evolving from the original Klimisch criteria (30) for ecotoxicology studies. For now, all criteria were weighed equally as we considered all of them to be crucial for generating reliable results. Future research, however, may provide a rationale for using unequal weights, which thus would lead to another outcome of the scoring. Finally, we emphasize that a protocol and scoring system for microplastic analytical studies should be seen as a product of the scientific community rather than a product of a limited set of authors. In this sense, we see the present paper as a starting point in assessing quality assurance criteria for microplastic analytical studies rather than the final stage.

Supporting Information

Click to copy section linkSection link copied!

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.est.8b01611.

  • Explanation and definition of scores and scoring of individual papers (PDF)

Terms & Conditions

Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

Author Information

Click to copy section linkSection link copied!
  • Corresponding Author
  • Authors
    • Enya Hermsen - Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen, The Netherlands
    • Svenja M. Mintenig - Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands;  KWR Watercycle Research Institute, Nieuwegein, The Netherlands
    • Ellen Besseling - Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen, The Netherlands;  Wageningen Marine Research, IJmuiden, The Netherlands;  Orcidhttp://orcid.org/0000-0003-0686-2173
  • Author Contributions

    E.H. and S.M.M. contributed equally to this work.

  • Notes
    The authors declare no competing financial interest.

Acknowledgments

Click to copy section linkSection link copied!

S.M.M. and A.A.K. acknowledge funding from the Dutch Technology Foundation TTW (project number 13940) and additional support from KWR, IMARES, NVWA, RIKILT, the Dutch Ministry of Infrastructure and the Environment, The Dutch Ministry of Health, Welfare and Sport, Wageningen Food & Biobased Research, STOWA, RIWA, and the Dutch water boards.

References

Click to copy section linkSection link copied!

This article references 88 other publications.

  1. 1
    GESAMP Sources, fate and effects of microplastics in the marine environment: part two of a global assessment; Kershaw, P. J., Rochman, C. M., eds.; IMO/FAO/UNESCO-IOC/UNIDO/WMO/IAEA/UN/ UNEP/UNDP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection; Rep. Stud. GESAMP, 2016; Vol. 93, p 220.
    Google Scholar
    There is no corresponding record for this reference.
  2. 2
    Wright, S. L.; Thompson, R. C.; Galloway, T. S. The physical impacts of microplastics on marine organisms: A review. Environ. Pollut. 2013, 178, 483– 492,  DOI: 10.1016/j.envpol.2013.02.031
    Google Scholar
    2
    The physical impacts of microplastics on marine organisms: A review
    Wright, Stephanie L.; Thompson, Richard C.; Galloway, Tamara S.
    Environmental Pollution (Oxford, United Kingdom) (2013), 178 (), 483-492CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    A review. Plastic debris at the micro-, and potentially also the nano-scale, are widespread in the environment. Microplastics have accumulated in oceans and sediments worldwide in recent years, with max. concns. reaching 100 000 particles m3. Due to their small size, microplastics may be ingested by low trophic fauna, with uncertain consequences for the health of the organism. This review focuses on marine invertebrates and their susceptibility to the phys. impacts of microplastic uptake. Some of the main points discussed are (1) an evaluation of the factors contributing to the bioavailability of microplastics including size and d.; (2) an assessment of the relative susceptibility of different feeding guilds; (3) an overview of the factors most likely to influence the phys. impacts of microplastics such as accumulation and translocation; and (4) the trophic transfer of microplastics. These findings are important in guiding future marine litter research and management strategies.
  3. 3
    Browne, M. A.; Galloway, T.; Thompson, R. Microplastic—an emerging contaminant of potential concern?. Integr. Environ. Assess. Manage. 2007, 3 (4), 559– 561,  DOI: 10.1002/ieam.5630030412
    Google Scholar
    There is no corresponding record for this reference.
  4. 4
    Chen, Q.; Reisser, J.; Cunsolo, S.; Kwadijk, C.; Kotterman, M.; Proietti, M.; Slat, B.; Ferrari, F. F.; Schwarz, A.; Levivier, A.; Yin, D.; Hollert, H.; Koelmans, A. A. Pollutants in Plastics within the North Pacific Subtropical Gyre. Environ. Sci. Technol. 2018, 52 (2), 446– 456,  DOI: 10.1021/acs.est.7b04682
    Google Scholar
    4
    Pollutants in Plastics within the North Pacific Subtropical Gyre
    Chen, Qiqing; Reisser, Julia; Cunsolo, Serena; Kwadijk, Christiaan; Kotterman, Michiel; Proietti, Maira; Slat, Boyan; Ferrari, Francesco F.; Schwarz, Anna; Levivier, Aurore; Yin, Daqiang; Hollert, Henner; Koelmans, Albert A.
    Environmental Science & Technology (2018), 52 (2), 446-456CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Here we report concns. of pollutants in floating plastics from the North Pacific accumulation zone (NPAC). We compared chem. concns. in plastics of different types and sizes, assessed ocean plastic potential risks using sediment quality criteria, and discussed the implications of our findings for bioaccumulation. Our results suggest that at least a fraction of the NPAC plastics is not in equil. with the surrounding seawater. For instance, "hard plastic" samples had significantly higher PBDE concns. than "nets and ropes" samples, and 29% of them had PBDE compn. similar to a widely used flame-retardant mixt. Our findings indicate that NPAC plastics may pose a chem. risk to organisms as 84% of the samples had at least one chem. exceeding sediment threshold effect levels. Furthermore, our surface trawls collected more plastic than biomass (180 times on av.), indicating that some NPAC organisms feeding upon floating particles may have plastic as a major component of their diets. If gradients for pollutant transfer from NPAC plastic to predators exist (as indicated by our fugacity ratio calcns.), plastics may play a role in transferring chems. to certain marine organisms.
  5. 5
    Lusher, A. L.; McHugh, M.; Thompson, R. C. Occurrence of microplastics in the gastrointestinal tract of pelagic and demersal fish from the English Channel. Mar. Pollut. Bull. 2013, 67 (1), 94– 99,  DOI: 10.1016/j.marpolbul.2012.11.028
    Google Scholar
    5
    Occurrence of microplastics in the gastrointestinal tract of pelagic and demersal fish from the English Channel
    Lusher, A. L.; McHugh, M.; Thompson, R. C.
    Marine Pollution Bulletin (2013), 67 (1-2), 94-99CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Microplastics are present in marine habitats worldwide and lab. studies show this material can be ingested, yet data on abundance in natural populations is limited. This study documents microplastics in 10 species of fish from the English Channel. 504 Fish were examd. and plastics found in the gastrointestinal tracts of 36.5%. All five pelagic species and all five demersal species had ingested plastic. Of the 184 fish that had ingested plastic the av. no. of pieces per fish was 1.90 ± 0.10. A total of 351 pieces of plastic were identified using FT-IR Spectroscopy; polyamide (35.6%) and the semi-synthetic cellulosic material, rayon (57.8%) were most common. There was no significant difference between the abundance of plastic ingested by pelagic and demersal fish. Hence, microplastic ingestion appears to be common, in relatively small quantities, across a range of fish species irresp. of feeding habitat. Further work is needed to establish the potential consequences.
  6. 6
    Foekema, E. M.; De Gruijter, C.; Mergia, M. T.; van Franeker, J. A.; Murk, A. J.; Koelmans, A. A. Plastic in North Sea Fish. Environ. Sci. Technol. 2013, 47 (15), 8818– 8824,  DOI: 10.1021/es400931b
    Google Scholar
    6
    Plastic in North Sea Fish
    Foekema, Edwin M.; De Gruijter, Corine; Mergia, Mekuria T.; van Franeker, Jan Andries; Murk, AlberTinka J.; Koelmans, Albert A.
    Environmental Science & Technology (2013), 47 (15), 8818-8824CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    To quantify the occurrence of ingested plastic in fish species caught at different geog. positions in the North Sea, and to test whether the fish condition is affected by ingestion of plastics, 1203 individual fish of seven common North Sea species were investigated: herring, gray gurnard, whiting, horse mackerel, haddock, atlantic mackerel, and cod. Plastic particles were found in 2.6% of the examd. fish and in five of the seven species. No plastics were found in gray gurnard and mackerel. In most cases, only one particle was found per fish, ranging in size from 0.04 to 4.8 mm. Only particles larger than 0.2 mm, being the diam. of the sieve used, were considered for the data analyses, resulting in a median particle size of 0.8 mm. The frequency of fish with plastic was significantly higher (5.4%) in the southern North Sea, than in the northern North Sea above 55°N (1.2%). The highest frequency (>33%) was found in cod from the English Channel. In addn., small fibers were initially detected in most of the samples, but their abundance sharply decreased when working under special clean air conditions. Therefore, these fibers were considered to be artifacts related to air born contamination and were excluded from the analyses. No relationship was found between the condition factor (size-wt. relationship) of the fish and the presence of ingested plastic particles.
  7. 7
    Neves, D.; Sobral, P.; Ferreira, J. L.; Pereira, T. Ingestion of microplastics by commercial fish off the Portuguese coast. Mar. Pollut. Bull. 2015, 101 (1), 119– 126,  DOI: 10.1016/j.marpolbul.2015.11.008
    Google Scholar
    7
    Ingestion of microplastics by commercial fish off the Portuguese coast
    Neves, Diogo; Sobral, Paula; Ferreira, Joana Lia; Pereira, Tania
    Marine Pollution Bulletin (2015), 101 (1), 119-126CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    The digestive tract contents of 263 individuals from 26 species of com. fish were examd. for microplastics. These were found in 17 species, corresponding to 19.8% of the fish of which 32.7% had ingested more than one microplastic. Of all the fish that ingested microplastics, 63.5% was benthic and 36.5% pelagic species. A total of 73 microplastics were recorded, 48 (65.8%) being fibers and 25 (34.2%) being fragments. Polymers were polypropylene, polyethylene, alkyd resin, rayon, polyester, nylon and acrylic. The mean of ingested microplastics was 0.27 ± 0.63 per fish, (n = 263). Pelagic fish ingested more particles and benthic fish ingested more fibers, but no significant differences were found. Fish with the highest no. of microplastics were from the mouth of the Tagus river. Scomber japonicus registered the highest mean of ingested microplastics, suggesting its potential as indicator species to monitor and investigate trends in ingested litter, in the MSFD marine regions.
  8. 8
    Mathalon, A.; Hill, P. Microplastic fibers in the intertidal ecosystem surrounding Halifax Harbor, Nova Scotia. Mar. Pollut. Bull. 2014, 81 (1), 69– 79,  DOI: 10.1016/j.marpolbul.2014.02.018
    Google Scholar
    8
    Microplastic fibers in the intertidal ecosystem surrounding Halifax Harbor, Nova Scotia
    Mathalon, Alysse; Hill, Paul
    Marine Pollution Bulletin (2014), 81 (1), 69-79CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Humans continue to increase the use and disposal of plastics by producing over 240 million tonnes per yr, polluting the oceans with persistent waste. The majority of plastic in the oceans are microplastics (<5 mm). In this study, the contamination of microplastic fibers was quantified in sediments from the intertidal zones of one exposed beach and two protected beaches along Nova Scotia's Eastern Shore. From the two protected beaches, polychaete worm fecal casts and live blue mussels (Mytilus edulis) were analyzed for microplastic content. Store-bought mussels from an aquaculture site were also analyzed. The av. microplastic abundance obsd. from 10 g sediment subsamples was between 20 and 80 fibers, with higher concns. at the high tide line from the exposed beach and at the low tide line from the protected beaches. Microplastic concns. from polychaete fecal casts resembled concns. quantified from low tide sediments. In two sep. mussel analyses, significantly more microplastics were enumerated in farmed mussels compared to wild ones.
  9. 9
    Romeo, T.; Pietro, B.; Pedà, C.; Consoli, P.; Andaloro, F.; Fossi, M. C. First evidence of presence of plastic debris in stomach of large pelagic fish in the Mediterranean Sea. Mar. Pollut. Bull. 2015, 95 (1), 358– 361,  DOI: 10.1016/j.marpolbul.2015.04.048
    Google Scholar
    9
    First evidence of presence of plastic debris in stomach of large pelagic fish in the Mediterranean Sea
    Romeo, Teresa; Pietro, Battaglia; Peda, Cristina; Consoli, Pierpaolo; Andaloro, Franco; Fossi, Maria Cristina
    Marine Pollution Bulletin (2015), 95 (1), 358-361CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    This study focuses, for the first time, on the presence of plastic debris in the stomach contents of large pelagic fish (Xiphias gladius, Thunnus thynnus and Thunnus alalunga) caught in the Mediterranean Sea between 2012 and 2013. Results highlighted the ingestion of plastics in the 18.2% of samples. The plastics ingested were microplastics (<5 mm), mesoplastics (5-25 mm) and macroplastics (>25 mm).These preliminary results represent an important initial phase in exploring two main ecotoxicol. aspects: (a) the assessment of the presence and impact of plastic debris on these large pelagic fish, and (b) the potential effects related to the transfer of contaminants on human health.
  10. 10
    Lusher, A. Microplastics in the Marine Environment: Distribution, Interactions and Effects. In Marine Anthropogenic Litter; Bergmann, M., Gutow, L., Klages, M., Eds.; Springer International Publishing: Cham, 2015; pp 245– 307.
    Google Scholar
    There is no corresponding record for this reference.
  11. 11
    Teuten, E. L.; Saquing, J. M.; Knappe, D. R. U.; Barlaz, M. A.; Jonsson, S.; Björn, A.; Rowland, S. J.; Thompson, R. C.; Galloway, T. S.; Yamashita, R.; Ochi, D.; Watanuki, Y.; Moore, C.; Viet, P. H.; Tana, T. S.; Prudente, M.; Boonyatumanond, R.; Zakaria, M. P.; Akkhavong, K.; Ogata, Y.; Hirai, H.; Iwasa, S.; Mizukawa, K.; Hagino, Y.; Imamura, A.; Saha, M.; Takada, H. Transport and release of chemicals from plastics to the environment and to wildlife. Philos. Trans. R. Soc., B 2009, 364 (1526), 2027– 2045,  DOI: 10.1098/rstb.2008.0284
    Google Scholar
    11
    Transport and release of chemicals from plastics to the environment and to wildlife
    Teuten, Emma L.; Saquing, Jovita M.; Knappe, Detlef R. U.; Barlaz, Morton A.; Jonsson, Susanne; Bjoern, Annika; Rowland, Steven J.; Thompson, Richard C.; Galloway, Tamara S.; Yamashita, Rei; Ochi, Daisuke; Watanuki, Yutaka; Moore, Charles; Viet, Pham Hung; Tana, Touch Seang; Prudente, Maricar; Boonyatumanond, Ruchaya; Zakaria, Mohamad P.; Akkhavong, Kongsap; Ogata, Yuko; Hirai, Hisashi; Iwasa, Satoru; Mizukawa, Kaoruko; Hagino, Yuki; Imamura, Ayako; Saha, Mahua; Takada, Hideshige
    Philosophical Transactions of the Royal Society, B: Biological Sciences (2009), 364 (1526), 2027-2045CODEN: PTRBAE; ISSN:0962-8436. (Royal Society)
    A review. Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain org. contaminants, including polychlorinated biphenyls (PCBs), polycyclic arom. hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2'-bis(p-chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concns. from sub ng g-1 to μg g-1. Some of these compds. are added during plastics manuf., while others adsorb from the surrounding seawater. Concns. of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calcns. and exptl. observations consistently show that polyethylene accumulates more org. contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a math. model using equil. partitioning and exptl. data have demonstrated the transfer of contaminants from plastic to organisms. A feeding expt. indicated that PCBs could transfer from contaminated plastics to streaked shearwater chicks. Plasticizers, other plastics additives and constitutional monomers also present potential threats in terrestrial environments because they can leach from waste disposal sites into groundwater and/or surface waters. Leaching and degrdn. of plasticizers and polymers are complex phenomena dependent on environmental conditions in the landfill and the chem. properties of each additive. Bisphenol A concns. in leachates from municipal waste disposal sites in tropical Asia ranged from sub μg l-1 to mg l-1 and were correlated with the level of economic development.
  12. 12
    Mato, Y.; Isobe, T.; Takada, H.; Kanehiro, H.; Ohtake, C.; Kaminuma, T. Plastic resin pellets as a transport medium for toxic chemicals in the marine environment. Environ. Sci. Technol. 2001, 35 (2), 318– 324,  DOI: 10.1021/es0010498
    Google Scholar
    12
    Plastic Resin Pellets as a Transport Medium for Toxic Chemicals in the Marine Environment
    Mato, Yukie; Isobe, Tomohiko; Takada, Hideshige; Kanehiro, Haruyuki; Ohtake, Chiyoko; Kaminuma, Tsuguchika
    Environmental Science and Technology (2001), 35 (2), 318-324CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Plastic resin pellets (small granules 0.1-0.5 cm diam.) are widely distributed in the ocean worldwide. They are an industrial raw material for the plastic industry and are unintentionally released to the environment during manufg. and transport. They are sometimes ingested by seabirds and other marine organisms; their adverse effects on organisms are a concern. In this, polychlorinated biphenyls (PCB), DDE, and nonylphenols (NP) were detected in polypropylene (PP) resin pellets collected from 4 Japanese coasts. Concns. of PCB (4-117 ng/g), DDE (0.16-3.1 ng/g), and NP (0.13-16 μg/g) varied among sample site. Concns. were comparable to those for suspended particles and bottom sediment collected from the same area as the pellets. Field adsorption expts. using PP virgin pellets demonstrated a significant, steady increase in PCB and DDE concns. throughout a 6-day expt., indicating the source of PCB and DDE is ambient seawater and that adsorption to pellet surfaces is the mechanism of enrichment. The major source of NP in the marine PP resin pellets was thought to be plastic additives and/or their degrdn. products. Comparison of PCB and DDE concns. in marine PP resin pellets with those in seawater suggested their high degree of accumulation (apparent adsorption coeff.: 105-106). The high accumulation potential suggested that plastic resin pellets serve as a transport medium and a potential source of toxic chems. in the marine environment.
  13. 13
    Diepens, N. J.; Koelmans, A. A. Accumulation of plastic debris and associated contaminants in aquatic food webs. Environ. Sci. Technol. 2018, 52, 8510– 8520,  DOI: 10.1021/acs.est.8b02515
    Google Scholar
    13
    Accumulation of Plastic Debris and Associated Contaminants in Aquatic Food Webs
    Diepens, Noel J.; Koelmans, Albert A.
    Environmental Science & Technology (2018), 52 (15), 8510-8520CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    The authors present a generic theor. model (MICROWEB) that simulates the transfer of microplastics and hydrophobic org. chems. (HOC) in food webs. The authors implemented the model for an Arctic case comprised of nine species including Atlantic cod and polar bear as top predator. The authors used the model to examine the effect of plastic ingestion on trophic transfer of microplastics and persistent HOCs (PCBs) and metabolizable HOCs (PAHs), spanning a wide range of hydrophobicities. Published data for values partition of PCBs and microplastics in the arctic area were used. In a scenario where HOCs in plastic and water are in equil., PCBs biomagnify less when more microplastic is ingested, because PCBs biomagnify less well from ingested plastic than from regular food. But PAHs biomagnify more when more microplastic is ingested, because plastic reduces the fraction of PAHs available for metabolization. The authors also explore nonequil. scenarios representative of additives that are leaching out, as well as sorbing HOCs, quant. showing how the above trends are strengthened and weakened, resp. The obsd. patterns were not very sensitive to modifications in the structure of the food web. The model can be used as a tool to assess prospective risks of exposure to microplastics and complex HOC mixts. for any food web, including those with relevance for human health.
  14. 14
    Cozar, A.; Echevarria, F.; Gonzalez-Gordillo, J. I.; Irigoien, X.; Ubeda, B.; Hernandez-Leon, S.; Palma, A. T.; Navarro, S.; Garcia-de-Lomas, J.; Ruiz, A.; Fernandez-de-Puelles, M. L.; Duarte, C. M. Plastic debris in the open ocean. Proc. Natl. Acad. Sci. U. S. A. 2014, 111 (28), 10239– 10244,  DOI: 10.1073/pnas.1314705111
    Google Scholar
    14
    Plastic debris in the open ocean
    Cozar, Andres; Echevarria, Fidel; Gonzalez-Gordillo, J. Ignacio; Irigoien, Xabier; Ubeda, Barbara; Hernandez-Leon, Santiago; Palma, Alvaro T.; Navarro, Sandra; Garcia-de-Lomas, Juan; Ruiz, Andrea; Fernandez-de-Puelles, Maria L.; Duarte, Carlos M.
    Proceedings of the National Academy of Sciences of the United States of America (2014), 111 (28), 10239-10244CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable d. However, the global load of plastic on the open ocean surface was estd. to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to det. the nature and significance of the impacts of plastic pollution in the ocean.
  15. 15
    Rochman, C. M.; Browne, M. A.; Underwood, A. J.; van Franeker, J. A.; Thompson, R. C. T.; Amaral-Zettler, L. A. The ecological impacts of marine debris: unraveling the demonstrated evidence from what is perceived. Ecology 2016, 97 (2), 302– 312,  DOI: 10.1890/14-2070.1
    Google Scholar
    15
    The ecological impacts of marine debris: unraveling the demonstrated evidence from what is perceived
    Rochman Chelsea M; Browne Mark Anthony; Underwood A J; van Franeker Jan A; Thompson Richard C; Amaral-Zettler Linda A
    Ecology (2016), 97 (2), 302-12 ISSN:0012-9658.
    Anthropogenic debris contaminates marine habitats globally, leading to several perceived ecological impacts. Here, we critically and systematically review the literature regarding impacts of debris from several scientific fields to understand the weight of evidence regarding the ecological impacts of marine debris. We quantified perceived and demonstrated impacts across several levels of biological organization that make up the ecosystem and found 366 perceived threats of debris across all levels. Two hundred and ninety-six of these perceived threats were tested, 83% of which were demonstrated. The majority (82%) of demonstrated impacts were due to plastic, relative to other materials (e.g., metals, glass) and largely (89%) at suborganismal levels (e.g., molecular, cellular, tissue). The remaining impacts, demonstrated at higher levels of organization (i.e., death to individual organisms, changes in assemblages), were largely due to plastic marine debris (> 1 mm; e.g., rope, straws, and fragments). Thus, we show evidence of ecological impacts from marine debris, but conclude that the quantity and quality of research requires improvement to allow the risk of ecological impacts of marine debris to be determined with precision. Still, our systematic review suggests that sufficient evidence exists for decision makers to begin to mitigate problematic plastic debris now, to avoid risk of irreversible harm.
  16. 16
    Besseling, E.; Foekema, E. M.; Van Franeker, J. A.; Leopold, M. F.; Kuhn, S.; Rebolledo, E. L. B.; Hesse, E.; Mielke, L.; Ijzer, J.; Kamminga, P.; Koelmans, A. A. Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae. Mar. Pollut. Bull. 2015, 95 (1), 248– 252,  DOI: 10.1016/j.marpolbul.2015.04.007
    Google Scholar
    16
    Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae
    Besseling, E.; Foekema, E. M.; Van Franeker, J. A.; Leopold, M. F.; Kuehn, S.; Bravo Rebolledo, E. L.; Hesse, E.; Mielke, L.; IJzer, J.; Kamminga, P.; Koelmans, A. A.
    Marine Pollution Bulletin (2015), 95 (1), 248-252CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water vols. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in intestines of a baleen whale (Megaptera novaeangliae). Contents of its gastrointestinal tract were sieved, dissolved in 10% potassium hydroxide and washed. From the remaining dried material, potential synthetic polymer particles were selected based on d. and appearance, and analyzed by Fourier transform IR (FTIR) spectroscopy. Several polymer types (polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, nylon) were found, in varying particle shapes: sheets, fragments and threads with a size of 1 mm to 17 cm. This diversity in polymer types and particle shapes, can be interpreted as a representation of the varying characteristics of marine plastic and the unselective way of ingestion by M. novaeangliae.
  17. 17
    Lusher, A. L.; Hernandez-Milian, G.; Berrow, S.; Rogan, E.; O’Connor, I. Incidence of marine debris in cetaceans stranded and bycaught in Ireland: Recent findings and a review of historical knowledge. Environ. Pollut. 2018, 232, 467– 476,  DOI: 10.1016/j.envpol.2017.09.070
    Google Scholar
    17
    Incidence of marine debris in cetaceans stranded and bycaught in Ireland: Recent findings and a review of historical knowledge
    Lusher, Amy L.; Hernandez-Milian, Gema; Berrow, Simon; Rogan, Emer; O'Connor, Ian
    Environmental Pollution (Oxford, United Kingdom) (2018), 232 (), 467-476CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    Interactions between marine mammals and plastic debris have been the focus of studies for many years. Examples of interactions include entanglement in discarded fishing items or the presence of ingested debris in digestive tracts. Plastics, including microplastics, are a form of marine debris globally distributed in coastal areas, oceanic waters and deep seas. Cetaceans which strand along the coast present a unique opportunity to study interactions between animals with macro- and microplastics. A combination of novel techniques and a review of historical data was used to complete an extensive study of cetaceans interacting with marine debris within Irish waters. Of the 25 species of marine mammals reported in Irish waters, at least 19 species were reported stranded between 1990 and 2015 (n = 2934). Two hundred and forty-one of the stranded cetaceans presented signs of possible entanglement or interactions with fisheries. Of this no., 52.7% were pos. identified as bycatch or as entangled in fisheries items, 26.6% were classified as mutilated and 20.7% could not be related to fisheries but showed signs of entanglement. In addn., 274 cetaceans were recorded as by-catch during observer programs targeting albacore tuna. Post-mortem examns. were carried out on a total of 528 stranded and bycaught individuals and 45 (8.5%) had marine debris in their digestive tracts: 21 contained macrodebris, 21 contained microdebris and three had both macro- and microdebris. Forty percent of the ingested debris were fisheries related items. All 21 individuals investigated with the novel method for microplastics contained microplastics, composed of fibers (83.6%) and fragments (16.4%). Deep diving species presented more incidences of macrodebris ingestion but it was not possible to investigate this relationship to ecol. habitat. More research on the plastic implications to higher trophic level organisms is required to understand the effects of these pollutants.
  18. 18
    Herzke, D.; Anker-Nilssen, T.; Nøst, T. H.; Götsch, A.; Christensen-Dalsgaard, S.; Langset, M.; Fangel, K.; Koelmans, A. A. Negligible Impact of Ingested Microplastics on Tissue Concentrations of Persistent Organic Pollutants in Northern Fulmars off Coastal Norway. Environ. Sci. Technol. 2016, 50 (4), 1924– 1933,  DOI: 10.1021/acs.est.5b04663
    Google Scholar
    There is no corresponding record for this reference.
  19. 19
    Koelmans, A. A. Modeling the Role of Microplastics in Bioaccumulation of Organic Chemicals to Marine Aquatic Organisms. A Critical Review. In Marine Anthropogenic Litter; Bergmann, M., Gutow, L., Klages, M., Eds.; Springer International Publishing: Cham, 2015; pp 309– 324.
    Google Scholar
    There is no corresponding record for this reference.
  20. 20
    Koelmans, A. A.; Besseling, E.; Wegner, A.; Foekema, E. M. Plastic as a Carrier of POPs to Aquatic Organisms: A Model Analysis. Environ. Sci. Technol. 2013, 47 (14), 7812– 7820,  DOI: 10.1021/es401169n
    Google Scholar
    20
    Plastic as a Carrier of POPs to Aquatic Organisms: A Model Analysis
    Koelmans, Albert A.; Besseling, Ellen; Wegner, Anna; Foekema, Edwin M.
    Environmental Science & Technology (2013), 47 (14), 7812-7820CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    It has been hypothesized that persistent org. pollutants (POPs) in microplastic may pose a risk to aquatic organisms. We develop and analyze a conceptual model that simulates the effects of plastic on bioaccumulation of POPs. The model accounts for diln. of exposure concn. by sorption of POPs to plastic (POP diln.), increased bioaccumulation by ingestion of plastic-contg. POPs (carrier), and decreased bioaccumulation by ingestion of clean plastic (cleaning). The model is parametrized for the lugworm Arenicola marina and evaluated against recently published bioaccumulation data for this species from lab. bioassays with polystyrene microplastic. Further scenarios include polyethylene microplastic, nanosized plastic, and open marine systems. Model anal. shows that plastic with low affinity for POPs such as polystyrene will have a marginal decreasing effect on bioaccumulation, governed by diln. For stronger sorbents such as polyethylene, the diln., carrier, and cleaning mechanism are more substantial. In closed lab. bioassay systems, diln. and cleaning dominate, leading to decreased bioaccumulation. Also in open marine systems a decrease is predicted due to a cleaning mechanism that counteracts biomagnification. However, the differences are considered too small to be relevant from a risk assessment perspective.
  21. 21
    Setälä, O.; Fleming-Lehtinen, V.; Lehtiniemi, M. Ingestion and transfer of microplastics in the planktonic food web. Environ. Pollut. 2014, 185 (0), 77– 83,  DOI: 10.1016/j.envpol.2013.10.013
    Google Scholar
    There is no corresponding record for this reference.
  22. 22
    Farrell, P.; Nelson, K. Trophic level transfer of microplastic: Mytilus edulis (L.) to Carcinus maenas (L.). Environ. Pollut. 2013, 177, 1– 3,  DOI: 10.1016/j.envpol.2013.01.046
    Google Scholar
    22
    Trophic level transfer of microplastic: Mytilus edulis (L.) to Carcinus maenas (L.)
    Farrell, Paul; Nelson, Kathryn
    Environmental Pollution (Oxford, United Kingdom) (2013), 177 (), 1-3CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    This study investigated the trophic transfer of microplastic from mussels to crabs. Mussels (Mytilus edulis) were exposed to 0.5 μm fluorescent polystyrene microspheres, then fed to crabs (Carcinus maenas). Tissue samples were then taken at intervals up to 21 days. The no. of microspheres in the hemolymph of the crabs was highest at 24 h (15 033 mL-1 ± SE 3146), and was almost gone after 21 days (267 mL-1 ± SE 120). The max. amt. of microspheres in the hemolymph was 0.04% of the amt. to which the mussels were exposed. Microspheres were also found in the stomach, hepatopancreas, ovary and gills of the crabs, in decreasing nos. over the trial period. This study is the first to show natural' trophic transfer of microplastic, and its translocation to hemolymph and tissues of a crab. This has implications for the health of marine organisms, the wider food web and humans.
  23. 23
    Wright, S. L.; Kelly, F. J. Plastic and Human Health: A Micro Issue?. Environ. Sci. Technol. 2017, 51 (12), 6634– 6647,  DOI: 10.1021/acs.est.7b00423
    Google Scholar
    23
    Plastic and Human Health: A Micro Issue?
    Wright, Stephanie L.; Kelly, Frank J.
    Environmental Science & Technology (2017), 51 (12), 6634-6647CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    A review. Microplastics are a pollutant of environmental concern. Their presence in food destined for human consumption and in air samples has been reported. Thus, microplastic exposure via diet or inhalation could occur, the human health effects of which are unknown. The current review article draws upon cross-disciplinary scientific literature to discuss and evaluate the potential human health impacts of microplastics and outlines urgent areas for future research. Key literature up to Sept. 2016 relating to bioaccumulation, particle toxicity, and chem. and microbial contaminants were critically examd. While this is an emerging field, complementary existing fields indicate potential particle, chem. and microbial hazards. If inhaled or ingested, microplastics may bioaccumulate and exert localized particle toxicity by inducing or enhancing an immune response. Chem. toxicity could occur due to the localized leaching of component monomers, endogenous additives, and adsorbed environmental pollutants. Chronic exposure is anticipated to be of greater concern due to the accumulative effect which could occur. This is expected to be dose-dependent, and a robust evidence-base of exposure levels is currently lacking. While there is potential for microplastics to impact human health, assessing current exposure levels and burdens is key. This information will guide future research into the potential mechanisms of toxicity and hence therein possible health effects.
  24. 24
    Filella, M. Questions of size and numbers in environmental research on microplastics: methodological and conceptual aspects. Environmental Chemistry 2015, 12 (5), 527– 538,  DOI: 10.1071/EN15012
    Google Scholar
    24
    Questions of size and numbers in environmental research on microplastics: methodological and conceptual aspects
    Filella, Montserrat
    Environmental Chemistry (2015), 12 (5), 527-538CODEN: ECNHAA; ISSN:1449-8979. (CSIRO Publishing)
    Environmental context Microplastics, either purposefully manufd. or formed by fragmentation of discarded 'end-of-life' macroplastic items, are accumulating in environmental compartments. As more and more data are collected on microplastics in the environment, discussion of two issues has become indispensable: (i) how reliable are the results in terms of the inherent capabilities and limitations of current methods used for sampling, counting and measuring microplastic particles; and (ii) how can the fate of microplastics be understood in the context of natural particles and colloids Abstr. A first important step in evaluating the impact of microplastic pollution in natural systems is assessing the reliability of the results obtained according to the inherent capabilities and limitations of the methods used for sampling, counting and measuring microplastic particles. This study, based on the crit. reading of 55 studies contg. quant. microplastic data in waters and sediments, is an attempt to analyze these issues in the light of existing knowledge in the field of natural colloid studies. Existing results are highly dependent on the sampling and methodol. procedure chosen and are essentially descriptive. Moreover, often they lack standardisation and adequate reporting of basic information such as the meaning of the size parameter measured. Colloid theory may provide the theor. background needed to explain microplastic behavior or, at least, to identify the parameters (e.g. d., surface characteristics, shape) that need to be known in order to gain a predictive knowledge of the subject. They are introduced and discussed. Finally, microplastics are not alone in environmental compartments. For this reason, when possible, published microplastic particle size distributions in natural waters have been quant. situated in the context of natural particles.
  25. 25
    Connors, K. A.; Dyer, S. D.; Belanger, S. E. Advancing the quality of environmental microplastic research. Environ. Toxicol. Chem. 2017, 36 (7), 1697– 1703,  DOI: 10.1002/etc.3829
    Google Scholar
    25
    Advancing the quality of environmental microplastic research
    Connors, Kristin A.; Dyer, Scott D.; Belanger, Scott E.
    Environmental Toxicology and Chemistry (2017), 36 (7), 1697-1703CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)
    Investigations into the environmental fate and effects of microplastics have been gaining momentum. Small, insol. polymeric particles are implicated by scientists in a wide variety of studies that are used to suggest a potential for widespread impacts in freshwater and marine pelagic and sediment environments. An exponential growth in scientific publications and an increase in regulatory attention have occurred. However, despite these efforts, the environmental hazard of these particles is still unknown. To evaluate the hazard of microplastics within a risk assessment context, we need a way to evaluate the quality of exptl. studies. We performed a thorough review of the quality and focus of environmental microplastic research, to understand the methodologies employed and how this may assist or distract from the ability of environmental risk assessors to evaluate microplastics. We provide guidance to improve the reliability and relevance of ecotoxicol. studies for regulatory and broader environmental assessments. Nine areas of needed improvement are identified and discussed. Important data gaps and exptl. limitations are highlighted. Environ Toxicol Chem 2017;9999:1-7. © 2017 SETAC.
  26. 26
    Hanvey, J. S.; Lewis, P. J.; Lavers, J. L.; Crosbie, N. D.; Pozo, K.; Clarke, B. O. A review of analytical techniques for quantifying microplastics in sediments. Anal. Methods 2017, 9 (9), 1369– 1383,  DOI: 10.1039/C6AY02707E
    Google Scholar
    There is no corresponding record for this reference.
  27. 27
    Vandermeersch, G.; Van Cauwenberghe, L.; Janssen, C. R.; Marques, A.; Granby, K.; Fait, G.; Kotterman, M. J. J.; Diogène, J.; Bekaert, K.; Robbens, J.; Devriese, L. A critical view on microplastic quantification in aquatic organisms. Environ. Res. 2015, 143, 46– 55,  DOI: 10.1016/j.envres.2015.07.016
    Google Scholar
    27
    A critical view on microplastic quantification in aquatic organisms
    Vandermeersch, Griet; Van Cauwenberghe, Lisbeth; Janssen, Colin R.; Marques, Antonio; Granby, Kit; Fait, Gabriella; Kotterman, Michiel J. J.; Diogene, Jorge; Bekaert, Karen; Robbens, Johan; Devriese, Lisa
    Environmental Research (2015), 143 (Part_B), 46-55CODEN: ENVRAL; ISSN:0013-9351. (Elsevier)
    Microplastics, plastic particles and fragments smaller than 5 mm, are ubiquitous in the marine environment. Ingestion and accumulation of microplastics have previously been demonstrated for diverse marine species ranging from zooplankton to bivalves and fish, implying the potential for microplastics to accumulate in the marine food web. In this way, microplastics can potentially impact food safety and human health. Although a few methods to quantify microplastics in biota have been described, no comparison and/or intercalibration of these techniques have been performed. Here we conducted a literature review on all available extn. and quantification methods. Two of these methods, involving wet acid destruction, were used to evaluate the presence of microplastics in field-collected mussels (Mytilus galloprovincialis) from three different "hotspot" locations in Europe (Po estuary, Italy; Tagus estuary, Portugal; Ebro estuary, Spain). An av. of 0.18±0.14 total microplastics g-1 w.w. for the Acid mix Method and 0.12±0.04 total microplastics g-1 w.w. for the Nitric acid Method was established. Addnl., in a pilot study an av. load of 0.13±0.14 total microplastics g-1 w.w. was recorded in com. mussels (Mytilus edulis and M. galloprovincialis) from five European countries (France, Italy, Denmark, Spain and The Netherlands). A detailed anal. and comparison of methods indicated the need for further research to develop a standardised operating protocol for microplastic quantification and monitoring.
  28. 28
    Wesch, C.; Bredimus, K.; Paulus, M.; Klein, R. Towards the suitable monitoring of ingestion of microplastics by marine biota: A review. Environ. Pollut. 2016, 218, 1200– 1208,  DOI: 10.1016/j.envpol.2016.08.076
    Google Scholar
    28
    Towards the suitable monitoring of ingestion of microplastics by marine biota: A review
    Wesch, Charlotte; Bredimus, Katja; Paulus, Martin; Klein, Roland
    Environmental Pollution (Oxford, United Kingdom) (2016), 218 (), 1200-1208CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    Monitoring plastic ingestion in marine biota is a difficult task, esp. regarding ubiquitous microplastics (particles of <5 mm). Due to their microscopic size, evidence for microplastic ingestion is often limited to lab. studies. The following review provides a comparison and assessment of different microplastic ingestion monitoring procedures. Emphasis is given to the most important steps of current monitoring practice: (1) selecting suitable indicator species, (2) sampling and sample processing, (3) anal. procedures and (4) the prevention of secondary contamination of the sample. Moreover, an overview on ingestion records of microplastics by different marine feeding guilds is presented, including filter, suspension and deposit feeders as well as predators and scavengers. Lastly, monitoring processes are addressed critically in terms of their suitability for achieving the aims of an appropriate monitoring program. Recommendations for future research priorities are presented with a focus on the necessity of standardized and comparable monitoring procedures in microplastic detection.
  29. 29
    Löder, M. G. J.; Gerdts, G. Methodology Used for the Detection and Identification of Microplastics - A Critical Appraisal. In Marine Anthropogenic Litter; Bergmann, M., Gutow, L., Klages, M., Eds.; Springer International Publishing: Berlin, 2015; pp 201– 227.
    Google Scholar
    There is no corresponding record for this reference.
  30. 30
    Klimisch, H. J.; Andreae, M.; Tillmann, U. A Systematic Approach for Evaluating the Quality of Experimental Toxicological and Ecotoxicological Data. Regul. Toxicol. Pharmacol. 1997, 25 (1), 1– 5,  DOI: 10.1006/rtph.1996.1076
    Google Scholar
    30
    A systematic approach for evaluating the quality of experimental toxicological and ecotoxicological data
    Klimisch, H.-J.; Andreae, M.; Tillmann, U.
    Regulatory Toxicology and Pharmacology (1997), 25 (1), 1-5CODEN: RTOPDW; ISSN:0273-2300. (Academic)
    The evaluation of the quality of data and their use in hazard and risk assessment as a systematic approach is described. Definitions are proposed for the reliability, relevance, and the adequacy of the data. Reliability is differentiated into 4 categories. Criteria relating to international testing stds. for categorizing reliability are developed. A systematic documentation of evaluating reliability esp. for use in the IUCLID database is proposed. This approach is intended to harmonize data evaluation processes worldwide. It may help the expert in subsequent assessments and should increase the clarity of evaluation.
  31. 31
    Kase, R.; Korkaric, M.; Werner, I.; Ågerstrand, M. Criteria for Reporting and Evaluating ecotoxicity Data (CRED): comparison and perception of the Klimisch and CRED methods for evaluating reliability and relevance of ecotoxicity studies. Environ. Sci. Eur. 2016, 28 (1), 7,  DOI: 10.1186/s12302-016-0073-x
    Google Scholar
    31
    Criteria for Reporting and Evaluating ecotoxicity Data (CRED): comparison and perception of the Klimisch and CRED methods for evaluating reliability and relevance of ecotoxicity studies
    Kase Robert; Werner Inge; Korkaric Muris; ¡ÑÜAgerstrand Marlene
    Environmental sciences Europe (2016), 28 (1), 7 ISSN:2190-4707.
    BACKGROUND: The regulatory evaluation of ecotoxicity studies for environmental risk and/or hazard assessment of chemicals is often performed using the method established by Klimisch and colleagues in 1997. The method was, at that time, an important step toward improved evaluation of study reliability, but lately it has been criticized for lack of detail and guidance, and for not ensuring sufficient consistency among risk assessors. RESULTS: A new evaluation method was thus developed: Criteria for Reporting and Evaluating ecotoxicity Data (CRED). The CRED evaluation method aims at strengthening consistency and transparency of hazard and risk assessment of chemicals by providing criteria and guidance for reliability and relevance evaluation of aquatic ecotoxicity studies. A two-phased ring test was conducted to compare and characterize the differences between the CRED and Klimisch evaluation methods. A total of 75 risk assessors from 12 countries participated. Results show that the CRED evaluation method provides a more detailed and transparent evaluation of reliability and relevance than the Klimisch method. Ring test participants perceived it to be less dependent on expert judgement, more accurate and consistent, and practical regarding the use of criteria and time needed for performing an evaluation. CONCLUSIONS: We conclude that the CRED evaluation method is a suitable replacement for the Klimisch method, and that its use may contribute to an improved harmonization of hazard and risk assessments of chemicals across different regulatory frameworks.
  32. 32
    Koelmans, A. A.; Besseling, E.; Foekema, E.; Kooi, M.; Mintenig, S.; Ossendorp, B. C.; Redondo-Hasselerharm, P. E.; Verschoor, A.; van Wezel, A. P.; Scheffer, M. Risks of Plastic Debris: Unravelling Fact, Opinion, Perception, and Belief. Environ. Sci. Technol. 2017, 51 (20), 11513– 11519,  DOI: 10.1021/acs.est.7b02219
    Google Scholar
    32
    Risks of Plastic Debris: Unravelling Fact, Opinion, Perception, and Belief
    Koelmans, Albert A.; Besseling, Ellen; Foekema, Edwin; Kooi, Merel; Mintenig, Svenja; Ossendorp, Bernadette C.; Redondo-Hasselerharm, Paula E.; Verschoor, Anja; van Wezel, Annemarie P.; Scheffer, Marten
    Environmental Science & Technology (2017), 51 (20), 11513-11519CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Researcher and media alarms caused plastic debris to be perceived as a major threat to humans and animals; however, although wasting plastics in the environment is clearly undesirable for aesthetic and economic reasons, actual environmental risks of different plastics and their assocd. chems. is largely unknown. This work showed how a systematic assessment of adverse outcome pathways based on ecol. relevant metrics for exposure and effect can bring risk assessment within reach. Results will help respond to the current public concern in a balanced way and allow policy-makers to take measures using scientifically sound reasons.
  33. 33
    Brown, L. D.; Cai, T. T.; DasGupta, A. Interval Estimation for a Binomial Proportion. Statistical Science 2001, 16 (2), 101– 117,  DOI: 10.1214/ss/1009213286
    Google Scholar
    There is no corresponding record for this reference.
  34. 34
    Kooi, M.; Nes, E. H. v.; Scheffer, M.; Koelmans, A. A. Ups and Downs in the Ocean: Effects of Biofouling on Vertical Transport of Microplastics. Environ. Sci. Technol. 2017, 51 (14), 7963– 7971,  DOI: 10.1021/acs.est.6b04702
    Google Scholar
    34
    Ups and Downs in the Ocean: Effects of Biofouling on Vertical Transport of Microplastics
    Kooi, Merel; Nes, Egbert H. van; Scheffer, Marten; Koelmans, Albert A.
    Environmental Science & Technology (2017), 51 (14), 7963-7971CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Recent studies suggest size-selective removal of small plastic particles from the ocean surface, an observation that remains unexplained. We studied one of the hypotheses regarding this size-selective removal: the formation of a biofilm on the microplastics (biofouling). We developed the first theor. model that is capable of simulating the effect of biofouling on the fate of microplastic. The model is based on settling, biofilm growth, and ocean depth profiles for light, water d., temp., salinity, and viscosity. Using realistic parameters, the model simulates the vertical transport of small microplastic particles over time, and predicts that the particles either float, sink to the ocean floor, or oscillate vertically, depending on the size and d. of the particle. The predicted size-dependent vertical movement of microplastic particles results in a max. concn. at intermediate depths. Consequently, relatively low abundances of small particles are predicted at the ocean surface, while at the same time these small particles may never reach the ocean floor. Our results hint at the fate of "lost" plastic in the ocean, and provide a start for predicting risks of exposure to microplastics for potentially vulnerable species living at these depths.
  35. 35
    Gall, S. C.; Thompson, R. C. The impact of debris on marine life. Mar. Pollut. Bull. 2015, 92 (1), 170– 179,  DOI: 10.1016/j.marpolbul.2014.12.041
    Google Scholar
    35
    The impact of debris on marine life
    Gall, S. C.; Thompson, R. C.
    Marine Pollution Bulletin (2015), 92 (1-2), 170-179CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Marine debris is listed among the major perceived threats to biodiversity, and is cause for particular concern due to its abundance, durability and persistence in the marine environment. An extensive literature search reviewed the current state of knowledge on the effects of marine debris on marine organisms. 340 original publications reported encounters between organisms and marine debris and 693 species. Plastic debris accounted for 92% of encounters between debris and individuals. Numerous direct and indirect consequences were recorded, with the potential for sublethal effects of ingestion an area of considerable uncertainty and concern. Comparison to the IUCN Red List highlighted that at least 17% of species affected by entanglement and ingestion were listed as threatened or near threatened. Hence where marine debris combines with other anthropogenic stressors it may affect populations, trophic interactions and assemblages.
  36. 36
    Claessens, M.; De Meester, S.; Van Landuyt, L.; De Clerck, K.; Janssen, C. R. Occurrence and distribution of microplastics in marine sediments along the Belgian coast. Mar. Pollut. Bull. 2011, 62 (10), 2199– 204,  DOI: 10.1016/j.marpolbul.2011.06.030
    Google Scholar
    36
    Occurrence and distribution of microplastics in marine sediments along the Belgian coast
    Claessens, Michiel; De Meester, Steven; Van Landuyt, Lieve; De Clerck, Karen; Janssen, Colin R.
    Marine Pollution Bulletin (2011), 62 (10), 2199-2204CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Plastic debris is known to undergo fragmentation at sea, which leads to the formation of microscopic particles of plastic; the so called microplastics'. Due to their buoyant and persistent properties, these microplastics have the potential to become widely dispersed in the marine environment through hydrodynamic processes and ocean currents. In this study, the occurrence and distribution of microplastics was investigated in Belgian marine sediments from different locations (coastal harbours, beaches and sublittoral areas). Particles were found in large nos. in all samples, showing the wide distribution of microplastics in Belgian coastal waters. The highest concns. were found in the harbours where total microplastic concns. of up to 390 particles kg-1 dry sediment were obsd., which is 15-50 times higher than reported max. concns. of other, similar study areas. The depth profile of sediment cores suggested that microplastic concns. on the beaches reflect the global plastic prodn. increase.
  37. 37
    Woodall, L. C.; Gwinnett, C.; Packer, M.; Thompson, R. C.; Robinson, L. F.; Paterson, G. L. J. Using a forensic science approach to minimize environmental contamination and to identify microfibres in marine sediments. Mar. Pollut. Bull. 2015, 95 (1), 40– 46,  DOI: 10.1016/j.marpolbul.2015.04.044
    Google Scholar
    37
    Using a forensic science approach to minimize environmental contamination and to identify microfibres in marine sediments
    Woodall, Lucy C.; Gwinnett, Claire; Packer, Margaret; Thompson, Richard C.; Robinson, Laura F.; Paterson, Gordon L. J.
    Marine Pollution Bulletin (2015), 95 (1), 40-46CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    There is growing evidence of extensive pollution of the environment by microplastic, with microfibres representing a large proportion of the microplastics seen in marine sediments. Since microfibres are ubiquitous in the environment, present in the lab. air and water, evaluating microplastic pollution is difficult. Incidental contamination is highly likely unless strict control measures are employed. Here we describe methods developed to minimize the amt. of incidental post-sampling contamination when quantifying marine microfibre pollution. We show that our protocol, adapted from the field of forensic fiber examn., reduces fiber abundance by 90% and enables the quick screening of fiber populations. These methods therefore allow an accurate est. of microplastics polluting marine sediments. In a case study from a series of samples collected on a research vessel, we use these methods to highlight the prevalence of microfibres as marine microplastics.
  38. 38
    Van Cauwenberghe, L.; Vanreusel, A.; Mees, J.; Janssen, C. R. Microplastic pollution in deep-sea sediments. Environ. Pollut. 2013, 182, 495– 499,  DOI: 10.1016/j.envpol.2013.08.013
    Google Scholar
    38
    Microplastic pollution in deep-sea sediments
    Van Cauwenberghe, Lisbeth; Vanreusel, Ann; Mees, Jan; Janssen, Colin R.
    Environmental Pollution (Oxford, United Kingdom) (2013), 182 (), 495-499CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    Microplastics are small plastic particles (<1 mm) originating from the degrdn. of larger plastic debris. These microplastics have been accumulating in the marine environment for decades and have been detected throughout the water column and in sublittoral and beach sediments worldwide. However, up to now, it has never been established whether microplastic presence in sediments is limited to accumulation hot spots such as the continental shelf, or whether they are also present in deep-sea sediments. Here we show, for the first time ever, that microplastics have indeed reached the most remote of marine environments: the deep sea. We found plastic particles sized in the micrometre range in deep-sea sediments collected at four locations representing different deep-sea habitats ranging in depth from 1100 to 5000 m. Our results demonstrate that microplastic pollution has spread throughout the world's seas and oceans, into the remote and largely unknown deep sea.
  39. 39
    Setälä, O.; Norkko, J.; Lehtiniemi, M. Feeding type affects microplastic ingestion in a coastal invertebrate community. Mar. Pollut. Bull. 2016, 102 (1), 95– 101,  DOI: 10.1016/j.marpolbul.2015.11.053
    Google Scholar
    39
    Feeding type affects microplastic ingestion in a coastal invertebrate community
    Setala, Outi; Norkko, Joanna; Lehtiniemi, Maiju
    Marine Pollution Bulletin (2016), 102 (1), 95-101CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Marine litter is one of the problems marine ecosystems face at present, coastal habitats and food webs being the most vulnerable as they are closest to the sources of litter. A range of animals (bivalves, free swimming crustaceans and benthic, deposit-feeding animals), of a coastal community of the northern Baltic Sea were exposed to relatively low concns. of 10 μm microbeads. The expt. was carried out as a small scale mesocosm study to mimic natural habitat. The beads were ingested by all animals in all exptl. concns. (5, 50 and 250 beads mL- 1). Bivalves (Mytilus trossulus, Macoma balthica) contained significantly higher amts. of beads compared with the other groups. Free-swimming crustaceans ingested more beads compared with the benthic animals that were feeding only on the sediment surface. Ingestion of the beads was concluded to be the result of particle concn., feeding mode and the encounter rate in a patchy environment.
  40. 40
    Redondo-Hasselerharm, P. E.; Falahudin, D.; Peeters, E. T. H. M.; Koelmans, A. A. Microplastic Effect Thresholds for Freshwater Benthic Macroinvertebrates. Environ. Sci. Technol. 2018, 52 (4), 2278– 2286,  DOI: 10.1021/acs.est.7b05367
    Google Scholar
    40
    Microplastic Effect Thresholds for Freshwater Benthic Macroinvertebrates
    Redondo-Hasselerharm, Paula E.; Falahudin, Dede; Peeters, Edwin T. H. M.; Koelmans, Albert A.
    Environmental Science & Technology (2018), 52 (4), 2278-2286CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Now that microplastics have been detected in lakes, rivers, and estuaries all over the globe, evaluating their effects on biota has become an urgent research priority. This is the first study that aims at detg. the effect thresholds for a battery of six freshwater benthic macroinvertebrates with different species traits, using a wide range of microplastic concns. Standardized 28 days single species bioassays were performed under environmentally relevant exposure conditions using polystyrene microplastics (20-500 μm) mixed with sediment at concns. ranging from 0 to 40% sediment dry wt. (dw). Microplastics caused no effects on the survival of Gammarus pulex, Hyalella azteca, Asellus aquaticus, Sphaerium corneum, and Tubifex spp. and no effects were found on the reprodn. of Lumbriculus variegatus. No significant differences in growth were found for H. azteca, A. aquaticus, S. corneum, L. variegatus, and Tubifex spp. However, G. pulex showed a significant redn. in growth (EC10 = 1.07% sediment dw) and microplastic uptake was proportional with microplastic concns. in sediment. These results indicate that although the risks of environmentally realistic concns. of microplastics may be low, they still may affect the biodiversity and the functioning of aquatic communities which after all also depend on the sensitive species.
  41. 41
    Davison, P.; Asch, R. G. Plastic ingestion by mesopelagic fishes in the North Pacific Subtropical Gyre. Mar. Ecol.: Prog. Ser. 2011, 432, 173– 180,  DOI: 10.3354/meps09142
    Google Scholar
    There is no corresponding record for this reference.
  42. 42
    OSPAR request on development of a common monitoring protocol for plastic particles in fish stomachs and selected shellfish on the basis of existing fish disease surveys. IICES Advice 2015, 1, 1– 6.
    Google Scholar
    There is no corresponding record for this reference.
  43. 43
    Cannon, S. M. E.; Lavers, J. L.; Figueiredo, B. Plastic ingestion by fish in the Southern Hemisphere: A baseline study and review of methods. Mar. Pollut. Bull. 2016, 107, 286– 291,  DOI: 10.1016/j.marpolbul.2016.03.057
    Google Scholar
    There is no corresponding record for this reference.
  44. 44
    Jabeen, K.; Su, L.; Li, J.; Yang, D.; Tong, C.; Mu, J.; Shi, H. Microplastics and mesoplastics in fish from coastal and fresh waters of China. Environ. Pollut. 2017, 221, 141– 149,  DOI: 10.1016/j.envpol.2016.11.055
    Google Scholar
    44
    Microplastics and mesoplastics in fish from coastal and fresh waters of China
    Jabeen, Khalida; Su, Lei; Li, Jiana; Yang, Dongqi; Tong, Chunfu; Mu, Jingli; Shi, Huahong
    Environmental Pollution (Oxford, United Kingdom) (2017), 221 (), 141-149CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    Plastic pollution is a growing global concern. In the present study, we investigated plastic pollution in 21 species of sea fish and 6 species of freshwater fish from China. All of the species were found to ingest micro- or mesoplastics. The av. abundance of microplastics varied from 1.1 to 7.2 items by individual and 0.2-17.2 items by gram. The av. abundance of mesoplastics varied from 0.2 to 3.0 items by individual and 0.1-3.9 items by gram. Microplastics were abundant in 26 species, accounting for 55.9-92.3% of the total no. of plastics items in each species. Thamnaconus septentrionalis contained the highest abundance of microplastics (7.2 items/individual). The av. abundance of plastics in sea benthopelagic fishes was significantly higher than in freshwater benthopelagic fishes by items/individual. The plastics were dominanted by fiber in shape, transparent in color and cellophane in compn. The proportion of plastics in the stomach to the intestines showed great variation in different species, ranging from 0.5 to 1.9 by items/individual. The stomach of Harpodon nehereus and intestines of Pampus cinereus contained the highest no. of plastics, (3.3) and (2.7), resp., by items/individual. Our results suggested that plastic pollution was widespread in the investigated fish species and showed higher abundance in comparison with worldwide studies. The ingestion of plastics in fish was closely related to the habitat and gastrointestinal tract structure. We highly recommend that the entire gastrointestinal tract and digestion process be used in future investigations of plastic pollution in fish.
  45. 45
    MSFD (Technical Subgroup on Marine Litter). Guidance on Monitoring of Marine Litter in European Seas , 2013.
    Google Scholar
    There is no corresponding record for this reference.
  46. 46
    Hermsen, E.; Pompe, R.; Besseling, E.; Koelmans, A. A. Detection of low numbers of microplastics in North Sea fish using strict quality assurance criteria. Mar. Pollut. Bull. 2017, 122 (1), 253– 258,  DOI: 10.1016/j.marpolbul.2017.06.051
    Google Scholar
    There is no corresponding record for this reference.
  47. 47
    Bellas, J.; Martínez-Armental, J.; Martínez-Cámara, A.; Besada, V.; Martínez-Gómez, C. Ingestion of microplastics by demersal fish from the Spanish Atlantic and Mediterranean coasts. Mar. Pollut. Bull. 2016, 109 (1), 55– 60,  DOI: 10.1016/j.marpolbul.2016.06.026
    Google Scholar
    47
    Ingestion of microplastics by demersal fish from the Spanish Atlantic and Mediterranean coasts
    Bellas, Juan; Martinez-Armental, Jose; Martinez-Camara, Ariana; Besada, Victoria; Martinez-Gomez, Concepcion
    Marine Pollution Bulletin (2016), 109 (1), 55-60CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Microplastic pollution has received increased attention over the last few years. This study documents microplastic ingestion in three com. relevant demersal fish species from the Spanish Atlantic and Mediterranean coasts, the lesser spotted dogfish Scyliorhinus canicula, the European hake Merluccius merluccius and the red mullet Mullus barbatus. Overall 212 fish were examd., 72 dogfish, 12 hakes and 128 red mullets. The percentage of fish with microplastics was 17.5% (15.3% dogfish, 18.8% red mullets and 16.7% hakes), averaging 1.56 ± 0.5 items per fish, and the size of the microplastics ranged from 0.38 to 3.1 mm. These fish species are used currently as biomonitors for marine pollution monitoring within the Spanish Marine Pollution Monitoring Program (SMP), and may be as well suitable candidates for monitoring spatial and temporal trends of ingested litter. The data presented here represent a baseline for the implementation of the Marine Strategy Framework Directive descriptor 10 in Spain.
  48. 48
    Lusher, A. L.; O’Donnell, C.; Officer, R.; O’Connor, I. Microplastic interactions with North Atlantic mesopelagic fish. ICES J. Mar. Sci. 2016, 73 (4), 1214– 1225,  DOI: 10.1093/icesjms/fsv241
    Google Scholar
    There is no corresponding record for this reference.
  49. 49
    Courtene-Jones, W.; Quinn, B.; Murphy, F.; Gary, S. F.; Narayanaswamy, B. E. Optimisation of enzymatic digestion and validation of specimen preservation methods for the analysis of ingested microplastics. Anal. Methods 2017, 9, 1437– 1445,  DOI: 10.1039/C6AY02343F
    Google Scholar
    49
    Optimisation of enzymatic digestion and validation of specimen preservation methods for the analysis of ingested microplastics
    Courtene-Jones, Winnie; Quinn, Brian; Murphy, Fionn; Gary, Stefan F.; Narayanaswamy, Bhavani E.
    Analytical Methods (2017), 9 (9), 1437-1445CODEN: AMNEGX; ISSN:1759-9679. (Royal Society of Chemistry)
    Microplastics are considered to be a widespread environmental contaminant. Due to their small size microplastics have the potential to be ingested by a range of aquatic organisms which mistake them for a food source and can suffer adverse impacts as a result. Development of standardised methods is imperative to provide reliable and meaningful data when analyzing microplastic ingestion by marine fauna. A range of proteolytic digestive enzymes (trypsin, papain and collagenase) were tested to establish optimum digestion efficacy of biol. samples and assess the effects of enzymes on microplastics; addnl. the applicability of freezing and formaldehyde followed by ethanol as specimen preservation techniques for microplastic research was investigated. Of the enzymes investigated, trypsin yielded the greatest digestive efficacy based on wt. redn. (88% ± 2.52 S.D.) at the lowest concn. (0.3125%) with no obsd. impacts on microplastics. Enumeration of microplastics from wild collected Mytilus edulis revealed mean nos. of 1.05 ± 0.66 S.D. (min.) to 4.44 ± 3.03 S.D. (max.) microplastic particles per g wet wt. mussel tissue depending on location. There was no significant difference based on preservation method on the quantification of ingested microplastics and no detrimental impacts were obsd. on the microplastics directly. Enzymic digestion using trypsin therefore provides a suitable, time and cost effective method to ext. microplastics from M. edulis. Furthermore the preservation methods did not have detrimental effects on microplastics, serving to highlight the suitability of biol. samples preserved either way for future inquiries into ingested microplastics.
  50. 50
    Desforges, J.-P. W.; Galbraith, M.; Ross, P. S. Ingestion of Microplastics by Zooplankton in the Northeast Pacific Ocean. Arch. Environ. Contam. Toxicol. 2015, 69 (3), 320– 330,  DOI: 10.1007/s00244-015-0172-5
    Google Scholar
    50
    Ingestion of Microplastics by Zooplankton in the Northeast Pacific Ocean
    Desforges, Jean-Pierre W.; Galbraith, Moira; Ross, Peter S.
    Archives of Environmental Contamination and Toxicology (2015), 69 (3), 320-330CODEN: AECTCV; ISSN:0090-4341. (Springer)
    Microplastics are increasingly recognized as being widespread in the world's oceans, but relatively little is known about ingestion by marine biota. In light of the potential for microplastic fibers and fragments to be taken up by small marine organisms, we examd. plastic ingestion by two foundation species near the base of North Pacific marine food webs, the calanoid copepod Neocalanus cristatus and the euphausiid Euphausia pacifia. We developed an acid digestion method to assess plastic ingestion by individual zooplankton and detected microplastics in both species. Encounter rates resulting from ingestion were 1 particle/every 34 copepods and 1/every 17 euphausiids (euphausiids > copepods; p = 0.01). Consistent with differences in the size selection of food between these two zooplankton species, the ingested particle size was greater in euphausiids (816 ± 108 μm) than in copepods (556 ± 149 μm) (p = 0.014). The contribution of ingested microplastic fibers to total plastic decreased with distance from shore in euphausiids (r2 = 70, p = 0.003), corresponding to patterns in our previous observations of microplastics in seawater samples from the same locations. This first evidence of microplastic ingestion by marine zooplankton indicate that species at lower trophic levels of the marine food web are mistaking plastic for food, which raises fundamental questions about potential risks to higher trophic level species. One concern is risk to salmon: We est. that consumption of microplastic-contg. zooplankton will lead to the ingestion of 2-7 microplastic particles/day by individual juvenile salmon in coastal British Columbia, and ≤91 microplastic particles/day in returning adults.
  51. 51
    Murray, F.; Cowie, P. R. Plastic contamination in the decapod crustacean Nephrops norvegicus (Linnaeus, 1758). Mar. Pollut. Bull. 2011, 62 (6), 1207– 1217,  DOI: 10.1016/j.marpolbul.2011.03.032
    Google Scholar
    51
    Plastic contamination in the decapod crustacean Nephrops norvegicus (Linnaeus, 1758)
    Murray, Fiona; Cowie, Phillip Rhys
    Marine Pollution Bulletin (2011), 62 (6), 1207-1217CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    The aim of this study was to det. the extent Nephrops consumes plastics in the Clyde Sea and if this intake occurs through their diet. Plastic contamination was found to be high in Nephrops, 83% of the animals sampled contained plastics (predominately filaments) in their stomachs. Tightly tangled balls of plastic strands were found in 62% of the animals studied but were least prevalent in animals which had recently moulted. No significant difference in plastic load was obsd. between males and females. Raman spectroscopy indicated that some of the microfilaments identified from gut contents could be sourced to fishing waste. Nephrops fed fish seeded with strands of polypropylene rope were found to ingest but not to excrete the strands. The fishery for Norway lobster, Nephrops norvegicus, is the most valuable in Scotland and the high prevalence of plastics in Nephrops may have implications for the health of the stock.
  52. 52
    Boerger, C. M.; Lattin, G. L.; Moore, S. L.; Moore, C. J. Plastic ingestion by planktivorous fishes in the North Pacific Central Gyre. Mar. Pollut. Bull. 2010, 60 (12), 2275– 2278,  DOI: 10.1016/j.marpolbul.2010.08.007
    Google Scholar
    52
    Plastic ingestion by planktivorous fishes in the North Pacific Central Gyre
    Boerger, Christiana M.; Lattin, Gwendolyn L.; Moore, Shelly L.; Moore, Charles J.
    Marine Pollution Bulletin (2010), 60 (12), 2275-2278CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    A significant amt. of marine debris has accumulated in the North Pacific Central Gyre (NPCG). The effects on larger marine organisms have been documented through cases of entanglement and ingestion; however, little is known about the effects on lower trophic level marine organisms. This study is the first to document ingestion and quantify the amt. of plastic found in the gut of common planktivorous fish in the NPCG. From Feb. 11 to 14, 2008, 11 neuston samples were collected by manta trawl in the NPCG. Plastic from each trawl and fish stomach was counted and weighed and categorized by type, size class and color. Approx. 35% of the fish studied had ingested plastic, averaging 2.1 pieces per fish. Addnl. studies are needed to det. the residence time of ingested plastics and their effects on fish health and the food chain implications.
  53. 53
    Karlsson, T. M.; Vethaak, A. D.; Almroth, B. C.; Ariese, F.; van Velzen, M.; Hassellöv, M.; Leslie, H. A. Screening for microplastics in sediment, water, marine invertebrates and fish: Method development and microplastic accumulation. Mar. Pollut. Bull. 2017, 122 (1), 403– 408,  DOI: 10.1016/j.marpolbul.2017.06.081
    Google Scholar
    53
    Screening for microplastics in sediment, water, marine invertebrates and fish: Method development and microplastic accumulation
    Karlsson, Therese M.; Vethaak, A. Dick; Almroth, Bethanie Carney; Ariese, Freek; van Velzen, Martin; Hasselloev, Martin; Leslie, Heather A.
    Marine Pollution Bulletin (2017), 122 (1-2), 403-408CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Measurements of microplastics in biota and abiotic matrixes are key elements of exposure and risk assessments for this emerging environmental pollutant. We investigated the abundance of microplastics in field-collected biota, sediment and water. An improved sediment extn. method, based on d. sepn. was developed. For anal. of microplastics in biota we found that an adapted enzymic digestion protocol using proteinase K performed best, with a 97% recovery of spiked plastic particles and no obsd. degrdn. effects on the plastics in subsequent Raman anal. Field anal. revealed that 8 of 9 tested invertebrate species from the North Sea and 68% of analyzed individuals of brown trout (Salmo trutta) from the Swedish West Coast had microplastics in them. Based on the no. of plastic particles per kg d.w. the microplastic concns. found in mussels were approx. a thousand-fold higher compared to those in sediment and surface water samples from the same location.
  54. 54
    Torre, M.; Digka, N.; Anastasopoulou, A.; Tsangaris, C.; Mytilineou, C. Anthropogenic microfibres pollution in marine biota. A new and simple methodology to minimize airborne contamination. Mar. Pollut. Bull. 2016, 113 (1), 55– 61,  DOI: 10.1016/j.marpolbul.2016.07.050
    Google Scholar
    There is no corresponding record for this reference.
  55. 55
    Liboiron, M.; Liboiron, F.; Wells, E.; Richárd, N.; Zahara, A.; Mather, C.; Bradshaw, H.; Murichi, J. Low plastic ingestion rate in Atlantic cod (Gadus morhua) from Newfoundland destined for human consumption collected through citizen science methods. Mar. Pollut. Bull. 2016, 113 (1), 428– 437,  DOI: 10.1016/j.marpolbul.2016.10.043
    Google Scholar
    There is no corresponding record for this reference.
  56. 56
    Devriese, L. I.; van der Meulen, M. D.; Maes, T.; Bekaert, K.; Paul-Pont, I.; Frère, L.; Robbens, J.; Vethaak, A. D. Microplastic contamination in brown shrimp (Crangon crangon, Linnaeus 1758) from coastal waters of the Southern North Sea and Channel area. Mar. Pollut. Bull. 2015, 98 (1), 179– 187,  DOI: 10.1016/j.marpolbul.2015.06.051
    Google Scholar
    56
    Microplastic contamination in brown shrimp (Crangon crangon, Linnaeus 1758) from coastal waters of the Southern North Sea and Channel area
    Devriese, Lisa I.; van der Meulen, Myra D.; Maes, Thomas; Bekaert, Karen; Paul-Pont, Ika; Frere, Laura; Robbens, Johan; Vethaak, A. Dick
    Marine Pollution Bulletin (2015), 98 (1-2), 179-187CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    This study assessed the capability of Crangon crangon (L.), an ecol. and com. important crustacean, of consuming plastics as an opportunistic feeder. We therefore detd. the microplastic content of shrimp in shallow water habitats of the Channel area and Southern part of the North Sea. Synthetic fibers ranging from 200 μm up to 1000 μm size were detected in 63% of the assessed shrimp and an av. value of 0.68 ± 0.55 microplastics/g w. w. (1.23 ± 0.99 microplastics/shrimp) was obtained for shrimp in the sampled area. The assessment revealed no spatial patterns in plastic ingestion, but temporal differences were reported. The microplastic uptake was significantly higher in Oct. compared to March. The results suggest that microplastics >20 μm are not able to translocate into the tissues.
  57. 57
    Wesch, C.; Elert, A. M.; Wörner, M.; Braun, U.; Klein, R.; Paulus, M. Assuring quality in microplastic monitoring: About the value of clean-air devices as essentials for verified data. Sci. Rep. 2017, 7 (1), 5424,  DOI: 10.1038/s41598-017-05838-4
    Google Scholar
    57
    Assuring quality in microplastic monitoring: About the value of clean-air devices as essentials for verified data
    Wesch Charlotte; Worner Manuel; Klein Roland; Paulus Martin; Elert Anna Maria; Braun Ulrike
    Scientific reports (2017), 7 (1), 5424 ISSN:.
    Avoiding aerial microfibre contamination of environmental samples is essential for reliable analyses when it comes to the detection of ubiquitous microplastics. Almost all laboratories have contamination problems which are largely unavoidable without investments in clean-air devices. Therefore, our study supplies an approach to assess background microfibre contamination of samples in the laboratory under particle-free air conditions. We tested aerial contamination of samples indoor, in a mobile laboratory, within a laboratory fume hood and on a clean bench with particles filtration during the examining process of a fish. The used clean bench reduced aerial microfibre contamination in our laboratory by 96.5%. This highlights the value of suitable clean-air devices for valid microplastic pollution data. Our results indicate, that pollution levels by microfibres have been overestimated and actual pollution levels may be many times lower. Accordingly, such clean-air devices are recommended for microplastic laboratory applications in future research work to significantly lower error rates.
  58. 58
    Rummel, C. D.; Löder, M. G. J.; Fricke, N. F.; Lang, T.; Griebeler, E. M.; Janke, M.; Gerdts, G. Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea. Mar. Pollut. Bull. 2016, 102 (1), 134– 141,  DOI: 10.1016/j.marpolbul.2015.11.043
    Google Scholar
    58
    Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea
    Rummel, Christoph D.; Loeder, Martin G. J.; Fricke, Nicolai F.; Lang, Thomas; Griebeler, Eva-Maria; Janke, Michael; Gerdts, Gunnar
    Marine Pollution Bulletin (2016), 102 (1), 134-141CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Plastic ingestion by marine biota has been reported for a variety of different taxa. In this study, we investigated 290 gastrointestinal tracts of demersal (cod, dab and flounder) and pelagic fish species (herring and mackerel) from the North and Baltic Sea for the occurrence of plastic ingestion. In 5.5% of all investigated fishes, plastic particles were detected, with 74% of all particles being in the microplastic (< 5 mm) size range. The polymer types of all found particles were analyzed by means of Fourier transform IR (FT-IR) spectroscopy. Almost 40% of the particles consisted of polyethylene (PE). In 3.4% of the demersal and 10.7% of the pelagic individuals, plastic ingestion was recorded, showing a significantly higher ingestion frequency in the pelagic feeders. The condition factor K was calcd. to test differences in the fitness status between individuals with and without ingested plastic, but no direct effect was detected.
  59. 59
    Davidson, K.; Dudas, S. E. Microplastic Ingestion by Wild and Cultured Manila Clams (Venerupis philippinarum) from Baynes Sound, British Columbia. Arch. Environ. Contam. Toxicol. 2016, 71 (2), 147– 156,  DOI: 10.1007/s00244-016-0286-4
    Google Scholar
    59
    Microplastic Ingestion by Wild and Cultured Manila Clams (Venerupis philippinarum) from Baynes Sound, British Columbia
    Davidson, Katie; Dudas, Sarah E.
    Archives of Environmental Contamination and Toxicology (2016), 71 (2), 147-156CODEN: AECTCV; ISSN:0090-4341. (Springer)
    Microplastics, plastic particles <5 mm, are an emerging concern in aquatic ecosystems. Because microplastics are small, they are available to many filter-feeding organisms, which can then be consumed by higher trophic level organisms, including humans. This study documents the quantity of microplastics present in wild and cultured Manila clams (Venerupis philippinarum). Three active shellfish farms and three ref. beaches (i.e., non-shellfish farm sites) in Baynes Sound, British Columbia were chosen to examine the microplastic concns. in wild and cultured Manila clams. Microplastics were isolated using a nitric acid digestion technique and enumerated from 54 clams (27 farmed and 27 non-farmed). Qual. attributes, such as color and microplastic type (fiber, fragment, or film) also were recorded. There was no significant difference (F = 1.29; df = 1,4; P = 0.289) between microplastic concns. in cultured and wild clams. Microplastic concns. ranged from 0.07 to 5.47 particles/g (from ref. beach and shellfish farm clams, resp.). Fibers were the dominant microplastic (90 %); colorless and dark gray fibers were the most common colors obsd. (36 and 26 %, resp.). Although this indicates that microplastics are definitely present in seafood consumed by humans, shellfish aquaculture operations do not appear to be increasing microplastic concns. in farmed clams in this region.
  60. 60
    Van Cauwenberghe, L.; Janssen, C. R. Microplastics in bivalves cultured for human consumption. Environ. Pollut. 2014, 193, 65– 70,  DOI: 10.1016/j.envpol.2014.06.010
    Google Scholar
    60
    Microplastics in bivalves cultured for human consumption
    Van Cauwenberghe, Lisbeth; Janssen, Colin R.
    Environmental Pollution (Oxford, United Kingdom) (2014), 193 (), 65-70CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    Microplastics are present throughout the marine environment and ingestion of these plastic particles (<1 mm) has been demonstrated in a lab. setting for a wide array of marine organisms. Here, we investigate the presence of microplastics in two species of com. grown bivalves: Mytilus edulis and Crassostrea gigas. Microplastics were recovered from the soft tissues of both species. At time of human consumption, M. edulis contains on av. 0.36 ± 0.07 particles g-1 (wet wt.), while a plastic load of 0.47 ± 0.16 particles g-1 ww was detected in C. gigas. As a result, the annual dietary exposure for European shellfish consumers can amt. to 11,000 microplastics per yr. The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estg. microplastic toxicity, estns. of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible.
  61. 61
    Löder, M. G. J.; Imhof, H. K.; Ladehoff, M.; Löschel, L. A.; Lorenz, C.; Mintenig, S.; Piehl, S.; Primpke, S.; Schrank, I.; Laforsch, C.; Gerdts, G. Enzymatic purification of microplastics in environmental samples. Environ. Sci. Technol. 2017, 51 (24), 14283– 14292,  DOI: 10.1021/acs.est.7b03055
    Google Scholar
    61
    Enzymatic Purification of Microplastics in Environmental Samples
    Loder Martin G J; Ladehoff Maike; Lorenz Claudia; Mintenig Svenja; Primpke Sebastian; Gerdts Gunnar; Imhof Hannes K; Loschel Lena A; Piehl Sarah; Schrank Isabella; Laforsch Christian
    Environmental science & technology (2017), 51 (24), 14283-14292 ISSN:.
    Micro-Fourier transform infrared (micro-FTIR) spectroscopy and Raman spectroscopy enable the reliable identification and quantification of microplastics (MPs) in the lower micron range. Since concentrations of MPs in the environment are usually low, the large sample volumes required for these techniques lead to an excess of coenriched organic or inorganic materials. While inorganic materials can be separated from MPs using density separation, the organic fraction impedes the ability to conduct reliable analyses. Hence, the purification of MPs from organic materials is crucial prior to conducting an identification via spectroscopic techniques. Strong acidic or alkaline treatments bear the danger of degrading sensitive synthetic polymers. We suggest an alternative method, which uses a series of technical grade enzymes for purifying MPs in environmental samples. A basic enzymatic purification protocol (BEPP) proved to be efficient while reducing 98.3 ± 0.1% of the sample matrix in surface water samples. After showing a high recovery rate (84.5 ± 3.3%), the BEPP was successfully applied to environmental samples from the North Sea where numbers of MPs range from 0.05 to 4.42 items m(-3). Experiences with different environmental sample matrices were considered in an improved and universally applicable version of the BEPP, which is suitable for focal plane array detector (FPA)-based micro-FTIR analyses of water, wastewater, sediment, biota, and food samples.
  62. 62
    Dehaut, A.; Cassone, A.-L.; Frère, L.; Hermabessiere, L.; Himber, C.; Rinnert, E.; Rivière, G.; Lambert, C.; Soudant, P.; Huvet, A.; Duflos, G.; Paul-Pont, I. Microplastics in seafood: Benchmark protocol for their extraction and characterization. Environ. Pollut. 2016, 215, 223– 233,  DOI: 10.1016/j.envpol.2016.05.018
    Google Scholar
    62
    Microplastics in seafood: Benchmark protocol for their extraction and characterization
    Dehaut, Alexandre; Cassone, Anne-Laure; Frere, Laura; Hermabessiere, Ludovic; Himber, Charlotte; Rinnert, Emmanuel; Riviere, Gilles; Lambert, Christophe; Soudant, Philippe; Huvet, Arnaud; Duflos, Guillaume; Paul-Pont, Ika
    Environmental Pollution (Oxford, United Kingdom) (2016), 215 (), 223-233CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    Pollution of the oceans by microplastics (<5 mm) represents a major environmental problem. To date, a limited no. of studies have investigated the level of contamination of marine organisms collected in situ. For extn. and characterization of microplastics in biol. samples, the crucial step is the identification of solvent(s) or chem.(s) that efficiently dissolve org. matter without degrading plastic polymers for their identification in a time and cost effective way. Most published papers, as well as OSPAR recommendations for the development of a common monitoring protocol for plastic particles in fish and shellfish at the European level, use protocols contg. nitric acid to digest the biol. tissues, despite reports of polyamide degrdn. with this chem. In the present study, six existing approaches were tested and their effects were compared on up to 15 different plastic polymers, as well as their efficiency in digesting biol. matrixes. Plastic integrity was evaluated through microscopic inspection, weighing, pyrolysis coupled with gas chromatog. and mass spectrometry, and Raman spectrometry before and after digestion. Tissues from mussels, crabs and fish were digested before being filtered on glass fiber filters. Digestion efficiency was evaluated through microscopical inspection of the filters and detn. of the relative removal of org. matter content after digestion. Five out of the six tested protocols led to significant degrdn. of plastic particles and/or insufficient tissue digestion. The protocol using a KOH 10% soln. and incubation at 60 °C during a 24 h period led to an efficient digestion of biol. tissues with no significant degrdn. on all tested polymers, except for cellulose acetate. This protocol appeared to be the best compromise for extn. and later identification of microplastics in biol. samples and should be implemented in further monitoring studies to ensure relevance and comparison of environmental and seafood product quality studies.
  63. 63
    Munno, K.; Helm, P. A.; Jackson, D. A.; Rochman, C.; Sims, A. Impacts of temperature and selected chemical digestion methods on microplastic particles. Environ. Toxicol. Chem. 2018, 37 (1), 91– 98,  DOI: 10.1002/etc.3935
    Google Scholar
    63
    Impacts of temperature and selected chemical digestion methods on microplastic particles
    Munno, Keenan; Helm, Paul A.; Jackson, Donald A.; Rochman, Chelsea; Sims, Alina
    Environmental Toxicology and Chemistry (2018), 37 (1), 91-98CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)
    Alk. and wet peroxide oxidn. chem. digestion techniques used to ext. microplastics from org. matrixes were assessed for recoveries and for impacts on ability to identify polymer types. Methods using wet peroxide oxidn. generated enough heat to result in the complete loss of some types of microplastic particles, and boiling tests confirmed that temps. >70 °C were responsible for the losses. Fourier transform IR spectroscopy (FT-IR) confirmed minimal alteration of the recovered polymers by the applied methods.
  64. 64
    Kühn, S.; van Werven, B.; van Oyen, A.; Meijboom, A.; Bravo Rebolledo, E. L.; van Franeker, J. A. The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms. Mar. Pollut. Bull. 2017, 115 (1–2), 86– 90,  DOI: 10.1016/j.marpolbul.2016.11.034
    Google Scholar
    64
    The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms
    Kuehn, Susanne; van Werven, Bernike; van Oyen, Albert; Meijboom, Andre; Bravo Rebolledo, Elisa L.; van Franeker, Jan A.
    Marine Pollution Bulletin (2017), 115 (1-2), 86-90CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    In studies of plastic ingestion by marine wildlife, visual sepn. of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solns. to dissolve org. materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irresp. of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) soln., with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solns. can be a useful approach in general quant. studies of plastic ingestion by marine wildlife.
  65. 65
    Cole, M.; Webb, H.; Lindeque, P.; Fileman, E. S.; Halsband, C.; Galloway, T. S. Isolation of microplastics in biota-rich seawater samples and marine organisms. Sci. Rep. 2015, 4 (4528), 1– 8,  DOI: 10.1038/srep04528
    Google Scholar
    There is no corresponding record for this reference.
  66. 66
    Catarino, A. I.; Thompson, R.; Sanderson, W.; Henry, T. B. Development and optimization of a standard method for extraction of microplastics in mussels by enzyme digestion of soft tissues. Environ. Toxicol. Chem. 2017, 36 (4), 947– 951,  DOI: 10.1002/etc.3608
    Google Scholar
    66
    Development and optimisation of a standard method for extraction of microplastics in mussels by enzyme digestion of soft tissues
    Catarino, Ana I.; Thompson, Richard; Sanderson, William; Henry, Theodore B.
    Environmental Toxicology and Chemistry (2017), 36 (4), 947-951CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)
    We compared procedures for digestion of mussel soft tissues and extn. of microplastics (MPs). Complete tissue digestion was achieved with 1M NaOH, 35% HNO3 and by 0.1 UHb/mL protease, but use of HNO3 caused unacceptable destruction of some MPs. Recovery of MPs spiked into mussels was similar (93 ± 10%) for NaOH and enzyme digestions. We recommend use of industrial enzymes based on digestion efficiency, MP recovery and avoidance of caustic chems. This article is protected by copyright. All rights reserved.
  67. 67
    Law, K. L.; Moret-Ferguson, S. E.; Goodwin, D. S.; Zettler, E. R.; De Force, E.; Kukulka, T.; Proskurowski, G. Distribution of Surface Plastic Debris in the Eastern Pacific Ocean from an 11-Year Data Set. Environ. Sci. Technol. 2014, 48 (9), 4732– 4738,  DOI: 10.1021/es4053076
    Google Scholar
    67
    Distribution of Surface Plastic Debris in the Eastern Pacific Ocean from an 11-Year Data Set
    Law, Kara Lavender; Moret-Ferguson, Skye E.; Goodwin, Deborah S.; Zettler, Erik R.; DeForce, Emelia; Kukulka, Tobias; Proskurowski, Giora
    Environmental Science & Technology (2014), 48 (9), 4732-4738CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    We present an extensive survey of floating plastic debris in the eastern North and South Pacific Oceans from more than 2500 plankton net tows conducted between 2001 and 2012. From these data we defined an accumulation zone (25 to 41°N, 130 to 180°W) in the North Pacific subtropical gyre that closely corresponds to centers of accumulation resulting from the convergence of ocean surface currents predicted by several oceanog. numerical models. Maximum plastic concns. from individual surface net tows exceeded 106 pieces km-2, with concns. decreasing with increasing distance from the predicted center of accumulation. Outside the North Pacific subtropical gyre the median plastic concn. was 0 pieces km-2. We were unable to detect a robust temporal trend in the data set, perhaps because of confounded spatial and temporal variability. Large spatiotemporal variability in plastic concn. causes order of magnitude differences in summary statistics calcd. over short time periods or in limited geog. areas. Utilizing all available plankton net data collected in the eastern Pacific Ocean (17.4°S to 61.0°N; 85.0 to 180.0°W) since 1999, we estd. a min. of 21 290 t of floating microplastic.
  68. 68
    Eriksen, M.; Mason, S.; Wilson, S.; Box, C.; Zellers, A.; Edwards, W.; Farley, H.; Amato, S. Microplastic pollution in the surface waters of the Laurentian Great Lakes. Mar. Pollut. Bull. 2013, 77 (1–2), 177– 82,  DOI: 10.1016/j.marpolbul.2013.10.007
    Google Scholar
    68
    Microplastic pollution in the surface waters of the Laurentian Great Lakes
    Eriksen, Marcus; Mason, Sherri; Wilson, Stiv; Box, Carolyn; Zellers, Ann; Edwards, William; Farley, Hannah; Amato, Stephen
    Marine Pollution Bulletin (2013), 77 (1-2), 177-182CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
    Neuston samples were collected at 21 stations during an ∼700 nautical mile (∼1300 km) expedition in July 2012 in the Laurentian Great Lakes of the United States using a 333 μm mesh manta trawl and analyzed for plastic debris. Although the av. abundance was approx. 43,000 microplastic particles/km2, station 20, downstream from two major cities, contained over 466,000 particles/km2, greater than all other stations combined. SEM anal. detd. nearly 20% of particles less than 1 mm, which were initially identified as microplastic by visual observation, were aluminum silicate from coal ash. Many microplastic particles were multi-colored spheres, which were compared to, and are suspected to be, microbeads from consumer products contg. microplastic particles of similar size, shape, texture and compn. The presence of microplastics and coal ash in these surface samples, which were most abundant where lake currents converge, are likely from nearby urban effluent and coal burning power plants.
  69. 69
    Imhof, H. K.; Laforsch, C.; Wiesheu, A. C.; Schmid, J.; Anger, P. M.; Niessner, R.; Ivleva, N. P. Pigments and plastic in limnetic ecosystems: A qualitative and quantitative study on microparticles of different size classes. Water Res. 2016, 98, 64– 74,  DOI: 10.1016/j.watres.2016.03.015
    Google Scholar
    69
    Pigments and plastic in limnetic ecosystems: A qualitative and quantitative study on microparticles of different size classes
    Imhof, Hannes K.; Laforsch, Christian; Wiesheu, Alexandra C.; Schmid, Johannes; Anger, Philipp M.; Niessner, Reinhard; Ivleva, Natalia P.
    Water Research (2016), 98 (), 64-74CODEN: WATRAG; ISSN:0043-1354. (Elsevier Ltd.)
    Recently, macroplastic (>5 mm) and esp. microplastic (<5 mm) particles have been reported as emerging contaminants in marine and limnetic ecosystems. Their coloration is gained by the addn. of pigments to the polymer blend which is the major component of the resp. product. However, color is also a feature of paint and coatings whereby the pigment is the major component. Once abraded from a surface, paint particles may enter the environment via similar pathways as microplastic particles. So far no detailed studies of microplastic particles (pigmented and non-pigmented) as well as paint particles have been performed focusing on very small microparticles (1-50 μm), in either marine or limnetic ecosystems. Using Raman microspectroscopy with a spatial resoln. down to 1 μm, we report a remarkable increase in the occurrence of (pigmented) microplastic particles below 500 μm. Among those, most particles were found at a size of ∼130 μm in a freshwater ecosystem (subalpine Lake Garda, Italy). Moreover, our qual. and quant. analyses revealed that the no. of paint microparticles significantly increased below the size range of 50 μm due to their brittleness (the smallest detected paint particle had a size of 4 μm). Inductively coupled plasma mass spectrometry measurements showed that both colored particles found in nature as well as virgin particles contain a high variety of metals such as cadmium, lead and copper. These additives may elicit adverse effects in biota ingesting these microparticles, thus paints and assocd. compds. may act as formerly overlooked contaminants in freshwater ecosystems.
  70. 70
    Peters, C. A.; Thomas, P. A.; Rieper, K. B.; Bratton, S. P. Foraging preferences influence microplastic ingestion by six marine fish species from the Texas Gulf Coast. Mar. Pollut. Bull. 2017, 124 (1), 82– 88,  DOI: 10.1016/j.marpolbul.2017.06.080
    Google Scholar
    There is no corresponding record for this reference.
  71. 71
    Remy, F.; Collard, F.; Gilbert, B.; Compère, P.; Eppe, G.; Lepoint, G. When Microplastic Is Not Plastic: The Ingestion of Artificial Cellulose Fibers by Macrofauna Living in Seagrass Macrophytodetritus. Environ. Sci. Technol. 2015, 49 (18), 11158– 11166,  DOI: 10.1021/acs.est.5b02005
    Google Scholar
    71
    When Microplastic Is Not Plastic: The Ingestion of Artificial Cellulose Fibers by Macrofauna Living in Seagrass Macrophytodetritus
    Remy, Francois; Collard, France; Gilbert, Bernard; Compere, Philippe; Eppe, Gauthier; Lepoint, Gilles
    Environmental Science & Technology (2015), 49 (18), 11158-11166CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    Dead leaves of the Neptune grass, Posidonia oceanica (L.) Delile, in the Mediterranean coastal zone, are colonized by an abundant detritivorous invertebrate community that is heavily predated by fishes. This community was sampled in August 2011, Nov. 2011, and March 2012 at 2 different sites in the Calvi Bay (Corsica). Ingested artificial fibers (AFs) of various sizes and colors were found in 27.6% of the digestive tracts of the 9 dominant species regardless of their trophic level or taxon. No seasonal, spatial, size, or species-specific significant differences were revealed; suggesting that invertebrates ingest AFs at const. rates. Results showed that, in the gut contents of invertebrates, varying by trophic level, and across trophic levels, the overall ingestion of AFs was low (∼1 fiber per organism). Raman spectroscopy revealed that the ingested AFs were composed of viscose, an artificial, cellulose-based polymer. Most of these AFs also appeared to have been colored by industrial dyes. Two dyes were identified: Direct Blue 22 and Direct Red 28. The latter is known for being carcinogenic for vertebrates, potentially causing environmental problems for the P. oceanica litter community. Techniques such as Raman spectroscopy are necessary to study the particles compn., instead of relying on fragment size or color to identify the particles ingested by animals.
  72. 72
    Käppler, A.; Windrich, F.; Loder, M. G. J.; Malanin, M.; Fischer, D.; Labrenz, M.; Eichhorn, K. J.; Voit, B. Identification of microplastics by FTIR and Raman microscopy: a novel silicon filter substrate opens the important spectral range below 1300 cm(−1) for FTIR transmission measurements. Anal. Bioanal. Chem. 2015, 407 (22), 6791– 6801,  DOI: 10.1007/s00216-015-8850-8
    Google Scholar
    72
    Identification of microplastics by FTIR and Raman microscopy: a novel silicon filter substrate opens the important spectral range below 1300 cm(-1) for FTIR transmission measurements
    Kappler Andrea; Windrich Frank; Loder Martin G J; Malanin Mikhail; Fischer Dieter; Labrenz Matthias; Eichhorn Klaus-Jochen; Voit Brigitte
    Analytical and bioanalytical chemistry (2015), 407 (22), 6791-801 ISSN:.
    The presence of microplastics in aquatic ecosystems is a topical problem and leads to the need of appropriate and reliable analytical methods to distinctly identify and to quantify these particles in environmental samples. As an example transmission, Fourier transform infrared (FTIR) imaging can be used to analyze samples directly on filters without any visual presorting, when the environmental sample was afore extracted, purified, and filtered. However, this analytical approach is strongly restricted by the limited IR transparency of conventional filter materials. Within this study, we describe a novel silicon (Si) filter substrate produced by photolithographic microstructuring, which guarantees sufficient transparency for the broad mid-infrared region of 4000-600 cm(-1). This filter type features holes with a diameter of 10 μm and exhibits adequate mechanical stability. Furthermore, it will be shown that our Si filter substrate allows a distinct identification of the most common microplastics, polyethylene (PE), and polypropylene (PP), in the characteristic fingerprint region (1400-600 cm(-1)). Moreover, using the Si filter substrate, a differentiation of microparticles of polyesters having quite similar chemical structure, like polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), is now possible, which facilitates a visualization of their distribution within a microplastic sample by FTIR imaging. Finally, this Si filter can also be used as substrate for Raman microscopy-a second complementary spectroscopic technique-to identify microplastic samples.
  73. 73
    Fries, E.; Dekiff, J. H.; Willmeyer, J.; Nuelle, M. T.; Ebert, M.; Remy, D. Identification of polymer types and additives in marine microplastic particles using pyrolysis-GC/MS and scanning electron microscopy. Environmental Science-Processes & Impacts 2013, 15 (10), 1949– 1956,  DOI: 10.1039/c3em00214d
    Google Scholar
    There is no corresponding record for this reference.
  74. 74
    Dümichen, E.; Eisentraut, P.; Bannick, C. G.; Barthel, A.-K.; Senz, R.; Braun, U. Fast identification of microplastics in complex environmental samples by a thermal degradation method. Chemosphere 2017, 174, 572– 584,  DOI: 10.1016/j.chemosphere.2017.02.010
    Google Scholar
    74
    Fast identification of microplastics in complex environmental samples by a thermal degradation method
    Duemichen, Erik; Eisentraut, Paul; Bannick, Claus Gerhard; Barthel, Anne-Kathrin; Senz, Rainer; Braun, Ulrike
    Chemosphere (2017), 174 (), 572-584CODEN: CMSHAF; ISSN:0045-6535. (Elsevier Ltd.)
    In order to det. the relevance of microplastic particles in various environmental media, comprehensive investigations are needed. However, no anal. method exists for fast identification and quantification. At present, optical spectroscopy methods like IR and RAMAN imaging are used. Due to their time consuming procedures and uncertain extrapolation, reliable monitoring is difficult. For analyzing polymers Py-GC-MS is a std. method. However, due to a limited sample amt. of about 0.5 mg it is not suited for anal. of complex sample mixts. like environmental samples. Therefore, we developed a new thermoanal. method as a first step for identifying microplastics in environmental samples. A sample amt. of about 20 mg, which assures the homogeneity of the sample, is subjected to complete thermal decompn. The specific degrdn. products of the resp. polymer are adsorbed on a solid-phase adsorber and subsequently analyzed by thermal desorption gas chromatog. mass spectrometry. For certain identification, the specific degrdn. products for the resp. polymer were selected first. Afterwards real environmental samples from the aquatic (three different rivers) and the terrestrial (bio gas plant) systems were screened for microplastics. Mainly polypropylene (PP), polyethylene (PE) and polystyrene (PS) were identified for the samples from the bio gas plant and PE and PS from the rivers. However, this was only the first step and quantification measurements will follow.
  75. 75
    Fischer, M.; Scholz-Böttcher, B. M. Simultaneous Trace Identification and Quantification of Common Types of Microplastics in Environmental Samples by Pyrolysis-Gas Chromatography–Mass Spectrometry. Environ. Sci. Technol. 2017, 51 (9), 5052– 5060,  DOI: 10.1021/acs.est.6b06362
    Google Scholar
    75
    Simultaneous Trace Identification and Quantification of Common Types of Microplastics in Environmental Samples by Pyrolysis-Gas Chromatography-Mass Spectrometry
    Fischer, Marten; Scholz-Boettcher, Barbara M.
    Environmental Science & Technology (2017), 51 (9), 5052-5060CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
    The content of microplastics (MP) in the environment is constantly growing. Since the environmental relevance, particularly bioavailability, rises with decreasing particle size, the knowledge of the MP proportion in habitats and organisms is of gaining importance. The reliable recognition of MP particles is limited and underlies substantial uncertainties. Therefore spectroscopically methods are necessary to ensure the plastic nature of isolated particles, det. the polymer type and obtain particle count related quant. data. In this study Curie-Point pyrolysis-gas chromatog.-mass spectrometry combined with thermochemolysis is shown to be an excellent anal. tool to simultaneously identify and optionally quantify MP in environmental samples on a polymer specific mass related trace level. The method is independent of any optical preselection or particle appearance. For this purpose polymer characteristic pyrolysis products and their indicative fragment ions were used to analyze eight common types of plastics. Further aspects of calibration, recoveries, and potential matrix effects are discussed. The method is exemplarily applied on selected fish samples after an enzymic-chem. pretreatment. This new approach with mass-related results is complementary to established FT-IR and Raman methods providing particle counts of individual polymer particles.
  76. 76
    Löder, M. G. J.; Kuczera, M.; Mintenig, S.; Lorenz, C.; Gerdts, G. Focal plane array detector-based micro-Fourier-transform infrared imaging for the analysis of microplastics in environmental samples. Environmental Chemistry 2015, 12 (5), 563– 581,  DOI: 10.1071/EN14205
    Google Scholar
    There is no corresponding record for this reference.
  77. 77
    Mintenig, S. M.; Bauerlein, P. S.; Koelmans, A. A.; Dekker, S. C.; van Wezel, A. P. Closing the gap between small and smaller: towards a framework to analyse nano- and microplastics in aqueous environmental samples. Environ. Sci.: Nano 2018, 5, 1640– 1649,  DOI: 10.1039/C8EN00186C
    Google Scholar
    77
    Closing the gap between small and smaller: towards a framework to analyse nano- and microplastics in aqueous environmental samples
    Mintenig, S. M.; Baeuerlein, P. S.; Koelmans, A. A.; Dekker, S. C.; van Wezel, A. P.
    Environmental Science: Nano (2018), 5 (7), 1640-1649CODEN: ESNNA4; ISSN:2051-8161. (Royal Society of Chemistry)
    Measuring concns. and sizes of micro- and nanoplastics in the environment is essential to assess the risks plastic particles could pose. Microplastics have been detected globally in a variety of aquatic ecosystems. The detn. of nanoplastics, however, is lagging behind due to higher methodol. challenges. Here, we propose a framework that can consistently det. a broad spectrum of plastic particle sizes in aquatic environmental samples. Anal. evidence is provided as proof of principle. FTIR microscopy is applied to detect microplastics. Nanoplastics are studied using field-flow-fractionation and pyrolysis GC-MS that gives information on the particle sizes and polymer types. Pyrolysis GC-MS is shown to be promising for the detection of nanoplastics in environmental samples as a mass of approx. 100 ng is required to identify polystyrene. Pre-concg. nanoplastics by crossflow ultrafiltration enables polystyrene to be identified when the original concn. in an aq. sample is >20μg L-1. Finally, we present an approach to est. polymer masses based on the two-dimensional microplastic shapes recorded during the anal. with FTIR microscopy. Our suite of techniques demonstrates that anal. of the entire size spectrum of plastic debris is feasible.
  78. 78
    Tanaka, K.; Takada, H. Microplastic fragments and microbeads in digestive tracts of planktivorous fish from urban coastal waters. Sci. Rep. 2016, 6, 34351,  DOI: 10.1038/srep34351
    Google Scholar
    78
    Microplastic fragments and microbeads in digestive tracts of planktivorous fish from urban coastal waters
    Tanaka, Kosuke; Takada, Hideshige
    Scientific Reports (2016), 6 (), 34351CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)
    We investigated microplastics in the digestive tracts of 64 Japanese anchovy (Engraulis japonicus) sampled in Tokyo Bay. Plastic was detected in 49 out of 64 fish (77%), with 2.3 pieces on av. and up to 15 pieces per individual. All of the plastics were identified by Fourier transform IR spectroscopy. Most were polyethylene (52.0%) or polypropylene (43.3%). Most of the plastics were fragments (86.0%), but 7.3% were beads, some of which were microbeads, similar to those found in facial cleansers. Eighty percent of the plastics ranged in size from 150 μm to 1000 μm, smaller than the reported size range of floating microplastics on the sea surface, possibly because the subsurface foraging behavior of the anchovy reflected the different size distribution of plastics between surface waters and subsurface waters. Engraulis spp. are important food for many humans and other organisms around the world. Our observations further confirm that microplastics have infiltrated the marine ecosystem, and that humans may be exposed to them. Because microplastics retain hazardous chems., increase in fish chem. exposure by the ingested plastics is of concern. Such exposure should be studied and compared with that in the natural diet.
  79. 79
    Wesch, C.; Barthel, A. K.; Braun, U.; Klein, R.; Paulus, M. No microplastics in benthic eelpout (Zoarces viviparus): An urgent need for spectroscopic analyses in microplastic detection. Environ. Res. 2016, 148, 36– 38,  DOI: 10.1016/j.envres.2016.03.017
    Google Scholar
    79
    No microplastics in benthic eelpout (Zoarces viviparus): An urgent need for spectroscopic analyses in microplastic detection
    Wesch, Charlotte; Barthel, Anne-Kathrin; Braun, Ulrike; Klein, Roland; Paulus, Martin
    Environmental Research (2016), 148 (), 36-38CODEN: ENVRAL; ISSN:0013-9351. (Elsevier)
    Monitoring the ingestion of microplastics is challenging and suitable detection techniques are insufficiently used. Thus, misidentifying natural for synthetic microfibres cannot be avoided. As part of a framework to monitor the ingestion of microplastics in eelpout, this short report addresses the accurate identification of microfibres. We show that, following visual inspections, putatively synthetic microfibres are indeed of natural origin, as ascertained by spectrometric analyses. Consequently, we call for an inclusion of spectroscopic techniques in standardized microplastic monitoring schemes.
  80. 80
    Li, J.; Yang, D.; Li, L.; Jabeen, K.; Shi, H. Microplastics in commercial bivalves from China. Environ. Pollut. 2015, 207, 190– 195,  DOI: 10.1016/j.envpol.2015.09.018
    Google Scholar
    80
    Microplastics in commercial bivalves from China
    Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong
    Environmental Pollution (Oxford, United Kingdom) (2015), 207 (), 190-195CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    We investigated microplastic pollution in 9 com. bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The no. of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on av. 10.5 items/g and exhibited the highest levels of microplastics by wt. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33-84% of the total microplastics calcd. by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in com. bivalves from China. More intensive investigations on microplastics should be conducted in seafood.
  81. 81
    Murphy, F.; Russell, M.; Ewins, C.; Quinn, B. The uptake of macroplastic & microplastic by demersal & pelagic fish in the Northeast Atlantic around Scotland. Mar. Pollut. Bull. 2017, 122 (1), 353– 359,  DOI: 10.1016/j.marpolbul.2017.06.073
    Google Scholar
    There is no corresponding record for this reference.
  82. 82
    Nadal, M. A.; Alomar, C.; Deudero, S. High levels of microplastic ingestion by the semipelagic fish bogue Boops boops (L.) around the Balearic Islands. Environ. Pollut. 2016, 214, 517– 523,  DOI: 10.1016/j.envpol.2016.04.054
    Google Scholar
    82
    High levels of microplastic ingestion by the semipelagic fish bogue Boops boops (L.) around the Balearic Islands
    Nadal, M. A.; Alomar, C.; Deudero, S.
    Environmental Pollution (Oxford, United Kingdom) (2016), 214 (), 517-523CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
    For the first time this study reports on the presence of microplastics (1 nm to <5 mm) in the gastrointestinal tracts of small semipelagic fish (Boops boops) in the Balearic Islands (Mediterranean Sea) from March to May 2014. The results show microplastic ingestion in 68% of full stomach samples with an av. of 3.75 items per fish. Only filament type microplastics were obsd. in B. boops full gastrointestinal tracts. The frequency of occurrence of microplastics was high, with values ranging from 42% to 80%, in comparison to the other ingested items. Spatial variability among locations is high, which suggests that this type of contamination is ubiquitously distributed and originates from multiple sources. The results are important and indirectly provide further evidence of the presence of microplastics, which can be ingested by biota, in the marine environment.
  83. 83
    Bråte, I. L. N.; Eidsvoll, D. P.; Steindal, C. C.; Thomas, K. V. Plastic ingestion by Atlantic cod (Gadus morhua) from the Norwegian coast. Mar. Pollut. Bull. 2016, 112 (1), 105– 110,  DOI: 10.1016/j.marpolbul.2016.08.034
    Google Scholar
    There is no corresponding record for this reference.
  84. 84
    Anastasopoulou, A.; Mytilineou, C.; Smith, C. J.; Papadopoulou, K. N. Plastic debris ingested by deep-water fish of the Ionian Sea (Eastern Mediterranean). Deep Sea Res., Part I 2013, 74 (0), 11– 13,  DOI: 10.1016/j.dsr.2012.12.008
    Google Scholar
    There is no corresponding record for this reference.
  85. 85
    Jantz, L. A.; Morishige, C. L.; Bruland, G. L.; Lepczyk, C. A. Ingestion of plastic marine debris by longnose lancetfish (Alepisaurus ferox) in the North Pacific Ocean. Mar. Pollut. Bull. 2013, 69 (1), 97– 104,  DOI: 10.1016/j.marpolbul.2013.01.019
    Google Scholar
    There is no corresponding record for this reference.
  86. 86
    Vendel, A. L.; Bessa, F.; Alves, V. E. N.; Amorim, A. L. A.; Patrício, J.; Palma, A. R. T. Widespread microplastic ingestion by fish assemblages in tropical estuaries subjected to anthropogenic pressures. Mar. Pollut. Bull. 2017, 117 (1), 448– 455,  DOI: 10.1016/j.marpolbul.2017.01.081
    Google Scholar
    There is no corresponding record for this reference.
  87. 87
    Wójcik-Fudalewska, D.; Normant-Saremba, M.; Anastácio, P. Occurrence of plastic debris in the stomach of the invasive crab Eriocheir sinensis. Mar. Pollut. Bull. 2016, 113 (1), 306– 311,  DOI: 10.1016/j.marpolbul.2016.09.059
    Google Scholar
    There is no corresponding record for this reference.
  88. 88
    Miranda, D. d. A.; de Carvalho-Souza, G. F. Are we eating plastic-ingesting fish?. Mar. Pollut. Bull. 2016, 103 (1), 109– 114,  DOI: 10.1016/j.marpolbul.2015.12.035
    Google Scholar
    There is no corresponding record for this reference.

Cited By

Click to copy section linkSection link copied!
Citation Statements
Explore this article's citation statements on scite.ai
powered by  Scite

This article is cited by 420 publications.

  1. Robin Lenz, Kristina Enders, Eva Cseperke Vizsolyi, Mareike Schumacher, Julia Lötsch, Martin G. J. Löder, Gabriele Eder, Yuliya Voronko, José Manuel Andrade-Garda, Soledad Muniategui-Lorenzo, Christian Laforsch, Dieter Fischer, Matthias Labrenz. What Goes Around Should Not Move Around: Immobilizing Microplastics as a New Approach for Analytical Ring Trials. Environmental Science & Technology 2024, 58 (50) , 22224-22234. https://doi.org/10.1021/acs.est.4c09427
  2. Denise M. Mitrano, Miriam L. Diamond, Jae-Hong Kim, Kam Chiu Tam, Min Yang, Zhanyun Wang. Balancing New Approaches and Harmonized Techniques in Nano- and Microplastics Research. ACS ES&T Water 2023, 3 (8) , 1972-1975. https://doi.org/10.1021/acsestwater.3c00282
  3. Denise M. Mitrano, Miriam L. Diamond, Jae-Hong Kim, Kam Chiu Tam, Min Yang, Zhanyun Wang. Balancing New Approaches and Harmonized Techniques in Nano- and Microplastics Research. Environmental Science & Technology Letters 2023, 10 (8) , 618-621. https://doi.org/10.1021/acs.estlett.3c00359
  4. Denise M. Mitrano, Miriam L. Diamond, Jae-Hong Kim, Kam Chiu Tam, Min Yang, Zhanyun Wang. Balancing New Approaches and Harmonized Techniques in Nano- and Microplastics Research. ACS ES&T Engineering 2023, 3 (7) , 906-909. https://doi.org/10.1021/acsestengg.3c00220
  5. Denise M. Mitrano, Miriam L. Diamond, Jae-Hong Kim, Kam Chiu Tam, Min Yang, Zhanyun Wang. Balancing New Approaches and Harmonized Techniques in Nano- and Microplastics Research. Environmental Science & Technology 2023, 57 (24) , 8841-8844. https://doi.org/10.1021/acs.est.3c04120
  6. Denise M. Mitrano, Miriam L. Diamond, Jae-Hong Kim, Kam Chiu Tam, Min Yang, Zhanyun Wang. Balancing New Approaches and Harmonized Techniques in Nano- and Microplastics Research. ACS Sustainable Chemistry & Engineering 2023, 11 (24) , 8702-8705. https://doi.org/10.1021/acssuschemeng.3c03221
  7. Róisín Nash, Haleigh Joyce, Elena Pagter, João Frias, Janine Guinan, Louise Healy, Fiona Kavanagh, Malcolm Deegan, David O’Sullivan. Deep Sea Microplastic Pollution Extends Out to Sediments in the Northeast Atlantic Ocean Margins. Environmental Science & Technology 2023, 57 (1) , 201-213. https://doi.org/10.1021/acs.est.2c05926
  8. Vanessa Morgado, Carla Palma, Ricardo J. N. Bettencourt da Silva. Bottom-Up Evaluation of the Uncertainty of the Quantification of Microplastics Contamination in Sediment Samples. Environmental Science & Technology 2022, 56 (15) , 11080-11090. https://doi.org/10.1021/acs.est.2c01828
  9. Zoë Harrold, Monica M. Arienzo, Meghan Collins, Julia M. Davidson, Xuelian Bai, Suja Sukumaran, John Umek. A Peristaltic Pump and Filter-Based Method for Aqueous Microplastic Sampling and Analysis. ACS ES&T Water 2022, 2 (2) , 268-277. https://doi.org/10.1021/acsestwater.1c00270
  10. Mengyu Bai, Yan Lin, Rachel R. Hurley, Lixin Zhu, Daoji Li. Controlling Factors of Microplastic Riverine Flux and Implications for Reliable Monitoring Strategy. Environmental Science & Technology 2022, 56 (1) , 48-61. https://doi.org/10.1021/acs.est.1c04957
  11. Chang-Gui Pan, Svenja M. Mintenig, Paula E. Redondo-Hasselerharm, Paula H. M. W. Neijenhuis, Ke-Fu Yu, Ying-Hui Wang, Albert A. Koelmans. Automated μFTIR Imaging Demonstrates Taxon-Specific and Selective Uptake of Microplastic by Freshwater Invertebrates. Environmental Science & Technology 2021, 55 (14) , 9916-9925. https://doi.org/10.1021/acs.est.1c03119
  12. Xiao-Xia Zhou, Shuai He, Yan Gao, Ze-Chen Li, Hai-Yuan Chi, Cheng-Jun Li, Du-Jia Wang, Bing Yan. Protein Corona-Mediated Extraction for Quantitative Analysis of Nanoplastics in Environmental Waters by Pyrolysis Gas Chromatography/Mass Spectrometry. Analytical Chemistry 2021, 93 (17) , 6698-6705. https://doi.org/10.1021/acs.analchem.1c00156
  13. Nur Hazimah Mohamed Nor, Merel Kooi, Noël J. Diepens, Albert A. Koelmans. Lifetime Accumulation of Microplastic in Children and Adults. Environmental Science & Technology 2021, 55 (8) , 5084-5096. https://doi.org/10.1021/acs.est.0c07384
  14. Jiaxin Feng, Hansen Zhao, Xiaoyun Gong, Meng-Chan Xia, Lesi Cai, Huan Yao, Xu Zhao, Zihe Yan, Zhanping Li, Honggang Nie, Xiaoxiao Ma, Sichun Zhang. In Situ Identification and Spatial Mapping of Microplastic Standards in Paramecia by Secondary-Ion Mass Spectrometry Imaging. Analytical Chemistry 2021, 93 (13) , 5521-5528. https://doi.org/10.1021/acs.analchem.0c05383
  15. Francisca Ribeiro, Elvis D. Okoffo, Jake W. O’Brien, Sarah Fraissinet-Tachet, Stacey O’Brien, Michael Gallen, Saer Samanipour, Sarit Kaserzon, Jochen F. Mueller, Tamara Galloway, Kevin V. Thomas. Response to Comment on “Quantitative Analysis of Selected Plastics in High-Commercial-Value Australian Seafood by Pyrolysis Gas Chromatography Mass Spectrometry”. Environmental Science & Technology 2020, 54 (23) , 15556-15557. https://doi.org/10.1021/acs.est.0c07097
  16. Vera N. de Ruijter, Paula E. Redondo-Hasselerharm, Todd Gouin, Albert A. Koelmans. Quality Criteria for Microplastic Effect Studies in the Context of Risk Assessment: A Critical Review. Environmental Science & Technology 2020, 54 (19) , 11692-11705. https://doi.org/10.1021/acs.est.0c03057
  17. Francisca Ribeiro, Elvis D. Okoffo, Jake W. O’Brien, Sarah Fraissinet-Tachet, Stacey O’Brien, Michael Gallen, Saer Samanipour, Sarit Kaserzon, Jochen F. Mueller, Tamara Galloway, Kevin V. Thomas. Quantitative Analysis of Selected Plastics in High-Commercial-Value Australian Seafood by Pyrolysis Gas Chromatography Mass Spectrometry. Environmental Science & Technology 2020, 54 (15) , 9408-9417. https://doi.org/10.1021/acs.est.0c02337
  18. Dounia Elkhatib, Vinka Oyanedel-Craver. A Critical Review of Extraction and Identification Methods of Microplastics in Wastewater and Drinking Water. Environmental Science & Technology 2020, 54 (12) , 7037-7049. https://doi.org/10.1021/acs.est.9b06672
  19. Jeff Wagner, Zhong-Min Wang, Sutapa Ghosal, Margaret Murphy, Stephen Wall, Anna-Marie Cook, William Robberson, Harry Allen. Nondestructive Extraction and Identification of Microplastics from Freshwater Sport Fish Stomachs. Environmental Science & Technology 2019, 53 (24) , 14496-14506. https://doi.org/10.1021/acs.est.9b05072
  20. Xiangzhen Kong, Albert A. Koelmans. Modeling Decreased Resilience of Shallow Lake Ecosystems toward Eutrophication due to Microplastic Ingestion across the Food Web. Environmental Science & Technology 2019, 53 (23) , 13822-13831. https://doi.org/10.1021/acs.est.9b03905
  21. France Collard, Johnny Gasperi, Geir W. Gabrielsen, Bruno Tassin. Plastic Particle Ingestion by Wild Freshwater Fish: A Critical Review. Environmental Science & Technology 2019, 53 (22) , 12974-12988. https://doi.org/10.1021/acs.est.9b03083
  22. Brian Nguyen, Dominique Claveau-Mallet, Laura M. Hernandez, Elvis Genbo Xu, Jeffrey M. Farner, Nathalie Tufenkji. Separation and Analysis of Microplastics and Nanoplastics in Complex Environmental Samples. Accounts of Chemical Research 2019, 52 (4) , 858-866. https://doi.org/10.1021/acs.accounts.8b00602
  23. Xiao-xia Zhou, Li-teng Hao, Huang-ying-zi Wang, Ying-jie Li, Jing-fu Liu. Cloud-Point Extraction Combined with Thermal Degradation for Nanoplastic Analysis Using Pyrolysis Gas Chromatography–Mass Spectrometry. Analytical Chemistry 2019, 91 (3) , 1785-1790. https://doi.org/10.1021/acs.analchem.8b04729
  24. Richard K. Cross, Sarah L. Roberts, Monika D. Jürgens, Andrew C. Johnson, Craig W. Davis, Todd Gouin. Ensuring representative sample volume predictions in microplastic monitoring. Microplastics and Nanoplastics 2025, 5 (1) https://doi.org/10.1186/s43591-024-00109-2
  25. Hengchen Li, Hongwei Lu, Sansan Feng, Yuxuan Xue, Xiaohan Zhang. Environmental drivers and assembly mechanisms of microplastics in plateau lakes. Journal of Hydrology 2025, 660 , 133388. https://doi.org/10.1016/j.jhydrol.2025.133388
  26. G. Cesarini, I. Donázar-Aramendía, L. Gallitelli, S. Secco, M. Orsini, S. De Santis, M. Scalici, A.J. Green, C. Coccia. Microplastic contamination in bivalves from urban estuaries: Are they sentinels for differences in pollution levels?. Marine Pollution Bulletin 2025, 218 , 118227. https://doi.org/10.1016/j.marpolbul.2025.118227
  27. Huachen Gao, Yujing Ge, Wei Song, Yi Gong, Jiangfeng Zhu. Little evidence suggests microplastics negatively impact embryo growth of a viviparous shark Prionace glauca. Aquatic Toxicology 2025, 286 , 107456. https://doi.org/10.1016/j.aquatox.2025.107456
  28. Chayanika Rathore, Mahua Saha, Aniket Desai, Priyansha Gupta, Akshata Naik. Driving aspects of microplastic uptake: Influence in the Bentho-Pelagic ecosystem and its associated ecological risks along the coast of Goa, India. Environmental Research 2025, 278 , 121589. https://doi.org/10.1016/j.envres.2025.121589
  29. Eduardo Estevan Barrientos, Hiraku Tanoiri, Masashi Yokota. Temporal variability of microplastics contaminant ingested by striped barnacles Amphibalanus amphitrite in tidal flat of the Tsurumi River estuary, Tokyo Bay Area, Japan. Regional Studies in Marine Science 2025, 85 , 104127. https://doi.org/10.1016/j.rsma.2025.104127
  30. Tauqeer Hussain, Muhammad Summer, Shaukat Ali, Rana Rashad Mahmood Khan, Muhammad Pervaiz, Zohaib Saeed. Micro and Nanoplastics in Ecosystems: Interrelated Sources, Risks, Pathways, Consequences, Mitigation, Challenges and Future Recommendations. Water, Air, & Soil Pollution 2025, 236 (7) https://doi.org/10.1007/s11270-025-08063-2
  31. Su Ji Heo, Nalae Moon, Ju Hee Kim. A systematic review and quality assessment of estimated daily intake of microplastics through food. Reviews on Environmental Health 2025, 40 (2) , 371-392. https://doi.org/10.1515/reveh-2024-0111
  32. Marina Rocha de Carvalho, Alef Fontinele Teixeira, Luana do Nascimento Dias, Larissa Gabrielle Pinheiro Ferreira, Suzany Pedrosa Nascimento, Amanda Caroline Nascimento Sousa, Antonio Carlos Leal de Castro, James Werllen de Jesus Azevedo, Marcelo Henrique Lopes Silva. Presence of microplastics in Sciades herzbergii (Bloch, 1794) captured in harbor areas of the Amazon coast, Maranhão, Brazil. Marine Pollution Bulletin 2025, 215 , 117862. https://doi.org/10.1016/j.marpolbul.2025.117862
  33. Esra Billur Balcıoğlu İlhan. A Comprehensive Identification, Distribution and Health Risk Assessment of Microplastics in Natural Mussels from the Shoreline of the Sea of Marmara, Türkiye. Sustainability 2025, 17 (10) , 4731. https://doi.org/10.3390/su17104731
  34. Harish Farale, K B Sreevidhya, Ayyappa Bathinapatla, Suvardhan Kanchi. Impact of plastic contaminants on marine ecosystems and advancement in the detection of micro/nano plastics: A review. Journal of Hazardous Materials Advances 2025, 18 , 100736. https://doi.org/10.1016/j.hazadv.2025.100736
  35. Chathura Dhanasinghe, Chih‐Ming Kao, Pu‐Fong Liu, Rao Y. Surampalli, Tian C. Zhang, Bashir M. Al‐Hashimi. Advanced Techniques for Sampling, Quantification, and Characterization of Microplastics. 2025, 69-106. https://doi.org/10.1002/9781394251100.ch4
  36. D.S. Wijetunge, S.P.K.K.A. Perera, N.M.O.A. Karunathilake, R.R.M.K.P. Ranatunga. Macro Issues of Microplastics. 2025, 465-494. https://doi.org/10.1002/9781394237029.ch24
  37. Ayankoya Yemi Ayankunle, Natalja Buhhalko, Karin Pachel, Erki Lember, Asya Drenkova-Tuhtan, Margit Heinlaan. Microplastics in Estonian wastewater treatment plants: First evaluation of baseline concentrations and stage-wise removal efficiency. Aquatic Toxicology 2025, 281 , 107305. https://doi.org/10.1016/j.aquatox.2025.107305
  38. Yureshi Umanda Jayaweera, Hennayaka Mudiyanselage Amasha Indu Hennayaka, Herath Mudiyanselage Lalinka Priyas Herath, Gajanayake Mudalige Pradeep Kumara, Mahagama Gedara Yohan Lasantha Mahagamage, Undugodage Dulanjali Rodrigo, Danushika Charyangi Manatunga. A Comprehensive Investigation of Microplastic Contamination and Polymer Toxicity in Farmed Shrimps; L. vannamei and P. monodon. Water, Air, & Soil Pollution 2025, 236 (3) https://doi.org/10.1007/s11270-025-07800-x
  39. Claudia Andrade, Taryn Sepúlveda, Bárbara Pinto, Cristóbal Rivera, Cristian Aldea, Mauricio Urbina. The feeding mode effect: influence on particle ingestion by four invertebrates from Sub-Antarctic and Antarctic waters. Environmental Science and Pollution Research 2025, 32 (13) , 8318-8339. https://doi.org/10.1007/s11356-025-36144-6
  40. Yanning Qiu, Svenja Mintenig, Margherita Barchiesi, Albert A. Koelmans. Using artificial intelligence tools for data quality evaluation in the context of microplastic human health risk assessments. Environment International 2025, 197 , 109341. https://doi.org/10.1016/j.envint.2025.109341
  41. Vera N. de Ruijter, Paula E. Redondo-Hasselerharm, Albert A. Koelmans. A brief history of microplastics effect testing: Guidance and prospect. Environmental Pollution 2025, 368 , 125711. https://doi.org/10.1016/j.envpol.2025.125711
  42. Amarachi P. Onyena, Mary E. Tekeme, Jessica C. Uwakwe, Deborah Aderibigbe, Kabari Sam. Baseline characterisation of microplastics in surface water, sediment, and seafood from the Escravos Estuary, Nigeria. Scientific African 2025, 27 , e02591. https://doi.org/10.1016/j.sciaf.2025.e02591
  43. Hailong Zhang, Qiannan Duan, Pengwei Yan, Jianchao Lee, Weidong Wu, Chi Zhou, Baoxin Zhai, Xiangyi Yang. Advancements and challenges in microplastic detection and risk assessment: Integrating AI and standardized methods. Marine Pollution Bulletin 2025, 212 , 117529. https://doi.org/10.1016/j.marpolbul.2025.117529
  44. Mohammed Manik, Md. Tauhid Hossain, Paolo Pastorino. Characterization and risk assessment of microplastics pollution in Mohamaya Lake, Bangladesh. Journal of Contaminant Hydrology 2025, 269 , 104487. https://doi.org/10.1016/j.jconhyd.2024.104487
  45. Yiping Luo, Ruiqi Hu, Ye Zheng, Ling Ding, Xinran Qiu, Jiansheng Yang, Xujun Liang, Xuetao Guo. Sampling, extraction, and analysis of micro- and nano-plastics in environmental and biological compartments: A review. TrAC Trends in Analytical Chemistry 2025, 183 , 118056. https://doi.org/10.1016/j.trac.2024.118056
  46. Mohammad Mehdi Chiani, Majid Rasta, Mojtaba S. Taleshi, Fatemeh Elmi. The role of organisms’ size in microplastic pollution monitoring: Insights from Mytilaster lineatus and Amphibalanus improvisus. Marine Environmental Research 2025, 204 , 106863. https://doi.org/10.1016/j.marenvres.2024.106863
  47. Noor Us Saher, Asmat Saleem Siddiqui, Abdul Hameed Baloch, Wajid Ali, Raheema Tahir, Dur e Shahwar, Muntaha Shah, Nayab Kanwal, Fakhar I. Abbas, Naureen Aziz Qureshi. A Review Notes on Role, Behavior, Risk Assessment Tools, and Adverse Outcomes of Metal and Microplastic Pollution in Benthic Sea Food Ecosystem. 2025, 285-332. https://doi.org/10.1007/978-3-031-75713-6_12
  48. João Pinto da Costa, Virgínia Gonçalves. The steps of microplastic analysis and their consistency. 2025, 81-114. https://doi.org/10.1016/B978-0-443-15779-0.00014-6
  49. Muhammad Adli Hanif, Naimah Ibrahim, Zaity Syazwani Mohd Odli. Overview of analysis of microplastics and nanoplastics. 2025, 39-61. https://doi.org/10.1016/B978-0-443-15779-0.00015-8
  50. Alexandra Ershova, Yulia Frank. Separation and purification of microplastics from the environmental samples. 2025, 135-154. https://doi.org/10.1016/B978-0-443-15779-0.00019-5
  51. Pavel Pořízka, Daniel Holub, Martin Kizovský, Ota Samek, Jozef Kaiser, Gabriela Kalčikova. Hyphenated Raman and laser spectroscopy for the characterization of microplastics in tissues. 2025, 441-451. https://doi.org/10.1016/B978-0-443-21834-7.00026-8
  52. Yi Gong, Huachen Gao, Zehao Guo, Xuemin Huang, Yunkai Li, Zezheng Li, Chenxuan Du, Feng Wu. Uncovering the global status of plastic presence in marine chondrichthyans. Reviews in Fish Biology and Fisheries 2024, 34 (4) , 1351-1369. https://doi.org/10.1007/s11160-024-09877-9
  53. Majid Rasta, Ali Khodadoust, Mojtaba S. Taleshi, Niloofar S. Lashkaryan, Xiaotao Shi. Potential use of gammarus (Pontogammarus maeoticus) and shrimp (Palaemon elegans) as biomonitors of microplastics pollution in coastal environments. Environmental Pollution 2024, 362 , 124959. https://doi.org/10.1016/j.envpol.2024.124959
  54. Dave T.F. Kuo, Yang-hsin Shih. How effective is score-based data quality assessment? An illustration with fish BCF data. Environmental Research 2024, 262 , 119880. https://doi.org/10.1016/j.envres.2024.119880
  55. Hiraku Tanoiri, Haruka Nakano, Hisayuki Arakawa, Masashi Yokota. Assessment of microplastic occurrence in tidal flat biota of the Tsurumi River estuary (Tokyo Bay, Japan): Preliminary study and first evidence. Regional Studies in Marine Science 2024, 77 , 103661. https://doi.org/10.1016/j.rsma.2024.103661
  56. M. Dewika, Kalaimani Markandan, J. Nor Ruwaida, Y.Y. Sara, Anjan Deb, N. Ahmad Irfan, Mohammad Khalid. Integrating the quintuple helix approach into atmospheric microplastics management policies for planetary health preservation. Science of The Total Environment 2024, 954 , 176063. https://doi.org/10.1016/j.scitotenv.2024.176063
  57. Benjamin de Jourdan, Danielle Philibert, Davide Asnicar, Craig Warren Davis. Microplastic biomonitoring studies in aquatic species: A review & quality assessment framework. Science of The Total Environment 2024, 957 , 177541. https://doi.org/10.1016/j.scitotenv.2024.177541
  58. Nelle Meyers, Kathrin Kopke, Natalja Buhhalko, Karin Mattsson, Colin R. Janssen, Gert Everaert, Bavo De Witte. Value for money: a cost-effectiveness analysis of microplastic analytics in seawater. Microplastics and Nanoplastics 2024, 4 (1) https://doi.org/10.1186/s43591-024-00081-x
  59. David Vanavermaete, Amy Lusher, Jakob Strand, Esteban Abad, Marinella Farré, Emilie Kallenbach, Michael Dekimpe, Katrien Verlé, Sebastian Primpke, Stefano Aliani, Bavo De Witte. Plastics in biota: technological readiness level of current methodologies. Microplastics and Nanoplastics 2024, 4 (1) https://doi.org/10.1186/s43591-024-00083-9
  60. Jordan A. Pitt, Scott M. Gallager, Sarah Youngs, Anna P. M. Michel, Mark E. Hahn, Neelakanteswar Aluru. The abundance and localization of environmental microplastics in gastrointestinal tract and muscle of Atlantic killifish (Fundulus heteroclitus): a pilot study. Microplastics and Nanoplastics 2024, 4 (1) https://doi.org/10.1186/s43591-024-00101-w
  61. Benedicta Yayra Fosu-Mensah, Nathanael Nii-Odai Laryea, Daniel Darko, Michael Mensah. Assessing microplastics contamination and characteristics in organic soil amendments in the Greater Accra Metropolitan Area of Ghana. Heliyon 2024, 10 (23) , e40882. https://doi.org/10.1016/j.heliyon.2024.e40882
  62. Caitlin Brawn, Bonnie M. Hamilton, Matthew S. Savoca, Mark L. Mallory, Jennifer F. Provencher. Examining ingested microplastics in fish: Considerations on filter pore size, analysis time, and material costs to design cost-effective projects. Marine Environmental Research 2024, 202 , 106785. https://doi.org/10.1016/j.marenvres.2024.106785
  63. Kun Pang, Fangyu Fu, Haoqi Wang, Shun Ding, Yanfen Fang, Xiang Liu. Sustainability-inspired upcycling of plastic waste into porous carbon nanobulks for water decontamination via peroxymonosulfate activation. Science of The Total Environment 2024, 950 , 175242. https://doi.org/10.1016/j.scitotenv.2024.175242
  64. V. V. Dhoble, L. B. Dama. Extraction of Polyethylene and Polypropylene Microplastic from Agriculture Soil. International Journal of Scientific Research in Science and Technology 2024, 11 (6) , 100-107. https://doi.org/10.32628/IJSRST2411495
  65. Rao M Uppu, Willie Peijnenburg, Sean M Hays. Comment on: “ Microplastic presence in dog and human testis and its potential association with sperm count and weights of testis and epididymis”. Toxicological Sciences 2024, 74 https://doi.org/10.1093/toxsci/kfae136
  66. Aunurohim Aunurohim, Miftakhul Sefti Raufanda, Dian Saptarini, Farid Kamal Muzaki, Romanus Edy Prabowo, Martinus Surya Ari Pamungkas, Sobrian Cahya Perdana Putra, Ekawati Ekawati, Nur Maulidhaturrafida, Shinta Cahyaning Dewi, Edo Danilyan. Microplastic-contamination in the flesh and gastrointestinal tract of nile tilapia (Oreochromis niloticus) reared in floating net cages at lake Ranu Grati, Pasuruan, East Java, Indonesia. Environmental Advances 2024, 17 , 100587. https://doi.org/10.1016/j.envadv.2024.100587
  67. Nelle Meyers, Gert Everaert, Kris Hostens, Natascha Schmidt, Dorte Herzke, Jean-Luc Fuda, Colin R. Janssen, Bavo De Witte. Towards reliable data: Validation of a machine learning-based approach for microplastics analysis in marine organisms using Nile red staining. Marine Pollution Bulletin 2024, 207 , 116804. https://doi.org/10.1016/j.marpolbul.2024.116804
  68. Kevin Leuenberger, Gabriel Erni-Cassola, Clara Leistenschneider, Patricia Burkhardt-Holm. Microplastic ingestion in five demersal, bathydemersal and bathypelagic fish species from the eastern Weddell Sea, Antarctica. Science of The Total Environment 2024, 946 , 174320. https://doi.org/10.1016/j.scitotenv.2024.174320
  69. Andrei-Emil Briciu. A Graphic Review of Studies on Ocean and Mediterranean Sea Environment Quality. Hydrology 2024, 11 (10) , 175. https://doi.org/10.3390/hydrology11100175
  70. Bahati Shabani Nzeyimana, Swagata Chakraborty, R. Priyadharshini, Mariaselvam Sheela Mary, M. Govindaraju. Micro/Nano-Plastic Pollution in Aquarium Systems. 2024, 225-256. https://doi.org/10.4018/979-8-3693-3447-8.ch010
  71. Luca Nalbone, Filippo Giarratana, Martina Genovese, Antonio Panebianco. Occurrence of microplastics in store-bought fresh and processed clams in Italy. Marine Pollution Bulletin 2024, 206 , 116739. https://doi.org/10.1016/j.marpolbul.2024.116739
  72. Qing Huang, Xiaoyi Wu, Guodong Cao, Jing Zhang, Pengfei Wu, Zongwei Cai. Mass spectrometry-based techniques for determination of microplastics in terrestrial ecosystems. TrAC Trends in Analytical Chemistry 2024, 178 , 117853. https://doi.org/10.1016/j.trac.2024.117853
  73. Dorcas Uaciquete, Kensuke Mitsunaga, Katsumi Aoyama, Keisuke Kitajima, Takashi Chiba, Daud Liace Jamal, Jheng-Jie Jiang, Yoshifumi Horie. Microplastic abundance in the semi-enclosed Osaka Bay, Japan. Environmental Science and Pollution Research 2024, 31 (36) , 49455-49467. https://doi.org/10.1007/s11356-024-34444-x
  74. Cui-Lan Bai, Dan Wang, Yu-Ling Luan, Si-Nan Huang, Liang-Ying Liu, Ying Guo. A review on micro- and nanoplastics in humans: Implication for their translocation of barriers and potential health effects. Chemosphere 2024, 361 , 142424. https://doi.org/10.1016/j.chemosphere.2024.142424
  75. Stephen Kneel, Caroline Gilleran Stephens, Alec Rolston, Ana M. Mendes, Liam Morrison, Suzanne Linnane. Microplastic contamination of intertidal sediment and cockles (Cerastoderma edule). Marine Pollution Bulletin 2024, 205 , 116568. https://doi.org/10.1016/j.marpolbul.2024.116568
  76. Nina Wootton, Bronwyn M. Gillanders, Sophie Leterme, Warwick Noble, Scott P. Wilson, Michelle Blewitt, Stephen E. Swearer, Patrick Reis-Santos. Research priorities on microplastics in marine and coastal environments: An Australian perspective to advance global action. Marine Pollution Bulletin 2024, 205 , 116660. https://doi.org/10.1016/j.marpolbul.2024.116660
  77. Yueping Zheng, Sirui Huang, Houyong Fan, Hanqi Liu, Jianan Xu, Nicholas J. Craig, Juan-Ying Li, Wenhui He, Lei Su. Microplastics in different tissues of historical and live samples of endangered mega-fish (Acipenser sinensis) and their potential relevance to exposure pathways. Aquatic Toxicology 2024, 272 , 106943. https://doi.org/10.1016/j.aquatox.2024.106943
  78. Kayla Mladinich, Bridget A. Holohan, Sandra E. Shumway, J. Evan Ward. Abundance of microplastics at and near a shellfish aquaculture farm: An eastern oyster (Crassostrea virginica) transplant study. Marine Environmental Research 2024, 199 , 106606. https://doi.org/10.1016/j.marenvres.2024.106606
  79. Zeliang Su, Liangfu Wei, Linyong Zhi, Xiaomei Huang, Xu Wang, Jun Wang. Microplastics in aquafeeds: Occurrence, sources, effects and considerations for aquatic food production. TrAC Trends in Analytical Chemistry 2024, 176 , 117760. https://doi.org/10.1016/j.trac.2024.117760
  80. Kamil Jurowski, Maciej Noga, Damian Kobylarz, Łukasz Niżnik, Alicja Krośniak. Multimodal Imaging Using Raman Spectroscopy and FTIR in a Single Analytical Instrument with a Microscope (Infrared Raman Microscopy AIRsight, Shimadzu): Opportunities and Applications. International Journal of Molecular Sciences 2024, 25 (13) , 6884. https://doi.org/10.3390/ijms25136884
  81. Pooja Yadav, Sweety Dahiya, Sangita Yadav, Deepak Dahiya, Manju Rani, Sudesh Chaudhary. Examining the Ecological Footprint of Microplastics: A Holistic Exploration from Genesis to Demise. Oriental Journal Of Chemistry 2024, 40 (3) , 788-793. https://doi.org/10.13005/ojc/400321
  82. Melkamu Biyana Regasa. New Approaches for Micro(Nano)Plastics Analysis. 2024, 471-492. https://doi.org/10.1002/9781394238163.ch20
  83. Vania Aparecida Sacco, Natana Raquel Zuanazzi, Amanda Selinger, João Henrique Alliprandini da Costa, Érika Spanhol Lemunie, Camila Luiza Comelli, Vinícius Abilhoa, Fernando Carlos de Sousa, Luis Fernando Fávaro, Lorena M. Rios Mendoza, Nédia de Castilhos Ghisi, Rosilene Luciana Delariva. What are the global patterns of microplastic ingestion by fish? A scientometric review. Environmental Pollution 2024, 350 , 123972. https://doi.org/10.1016/j.envpol.2024.123972
  84. Sijia Gao, Natalie Orlowski, Franziska Kristin Bopf, Lutz Breuer. A review on microplastics in major European rivers. WIREs Water 2024, 11 (3) https://doi.org/10.1002/wat2.1713
  85. Prabhakar Sharma, Prateek Sharma, Kumar Abhishek. Sampling, separation, and characterization methodology for quantification of microplastic from the environment. Journal of Hazardous Materials Advances 2024, 14 , 100416. https://doi.org/10.1016/j.hazadv.2024.100416
  86. Xiaoping Sun, Ruiping Yang, Jing Ji, Zebin Zhu, Jason C. White, Yu Shen. An evaluation of microplastic contamination in the marine waters and species in the coastal region of the South Yellow Sea, China. Journal of Hazardous Materials 2024, 469 , 134018. https://doi.org/10.1016/j.jhazmat.2024.134018
  87. Elvis D. Okoffo, Kevin V. Thomas. Mass quantification of nanoplastics at wastewater treatment plants by pyrolysis–gas chromatography–mass spectrometry. Water Research 2024, 254 , 121397. https://doi.org/10.1016/j.watres.2024.121397
  88. Parisa Falakdin, Adrian Lopez-Rosales, Jose Andrade, Elisa Terzaghi, Antonio Di Guardo, Soledad Muniategui-Lorenzo. Comparison of microplastic type, size, and composition in atmospheric and foliage samples in an urban scenario. Environmental Pollution 2024, 349 , 123911. https://doi.org/10.1016/j.envpol.2024.123911
  89. Paula E. Redondo-Hasselerharm, Andreu Rico, Esperanza Huerta Lwanga, Cornelis A.M. van Gestel, Albert A. Koelmans. Source-specific probabilistic risk assessment of microplastics in soils applying quality criteria and data alignment methods. Journal of Hazardous Materials 2024, 467 , 133732. https://doi.org/10.1016/j.jhazmat.2024.133732
  90. Natalya S. Salikova, Javier Rodrigo-Ilarri, Lyudmila A. Makeyeva, María-Elena Rodrigo-Clavero, Zhulduz O. Tleuova, Anar D. Makhmutova. Monitoring of Microplastics in Water and Sediment Samples of Lakes and Rivers of the Akmola Region (Kazakhstan). Water 2024, 16 (7) , 1051. https://doi.org/10.3390/w16071051
  91. Pazhamthavalathil Anil Athulya, Yojana Waychal, Andres Rodriguez-Seijo, Sandhya Devalla, C. George Priya Doss, Natarajan Chandrasekaran. Microplastic interactions in the agroecosystems: methodological advances and limitations in quantifying microplastics from agricultural soil. Environmental Geochemistry and Health 2024, 46 (3) https://doi.org/10.1007/s10653-023-01800-8
  92. Narges Nejat, Masoud Sattari, Reza Mohsenpour, Xiaotao Shi, Majid Rasta. Microplastics abundance, distribution and composition in surface waters, sediments and fish species from Amir˗Kalayeh Wetland, Northern Iran. Environmental Science and Pollution Research 2024, 31 (14) , 22024-22037. https://doi.org/10.1007/s11356-024-32627-0
  93. Yinan He, Jungang Lu, Changjun Li, Xiaohui Wang, Chunhua Jiang, Lixin Zhu, Xinyu Bu, Khalida Jabeen, TuanLinh Tran Vo, Daoji Li. From pollution to solutions: Insights into the sources, transport and management of plastic debris in pristine and urban rivers. Environmental Research 2024, 245 , 118024. https://doi.org/10.1016/j.envres.2023.118024
  94. Nina R. Jones, Alix M. de Jersey, Jennifer L. Lavers, Thomas Rodemann, Jack Rivers-Auty. Identifying laboratory sources of microplastic and nanoplastic contamination from the air, water, and consumables. Journal of Hazardous Materials 2024, 465 , 133276. https://doi.org/10.1016/j.jhazmat.2023.133276
  95. João Frias, Haleigh Joyce, Loann Brozzetti, Elena Pagter, Mateja Švonja, Fiona Kavangh, Róisín Nash. Spatial monitoring of microplastics in environmental matrices from Galway Bay, Ireland. Marine Pollution Bulletin 2024, 200 , 116153. https://doi.org/10.1016/j.marpolbul.2024.116153
  96. Anita Jemec Kokalj, Gabriela Kalčíková, Salla Selonen, Thijs Bosker, Damjana Drobne, Darina Dvořáková, Jakub Hofman, Rachel Hurley, Sarmite Kernchen, Christian Laforsch, Martin G.J. Löder, Sam van Loon, Paula E. Redondo-Hasselerharm, Vili Saartama, Klára Šmídová, Aristeidis S. Tsagkaris, Laura J. Zantis, Luca Nizzetto, Cornelis A.M. van Gestel. Strategy towards producing relevant and reliable data for the hazard assessment of micro- and nanoplastics in agricultural soils. TrAC Trends in Analytical Chemistry 2024, 172 , 117567. https://doi.org/10.1016/j.trac.2024.117567
  97. Mansoor Ahmad Bhat, Eftade O. Gaga, Kadir Gedik. How can contamination be prevented during laboratory analysis of atmospheric samples for microplastics?. Environmental Monitoring and Assessment 2024, 196 (2) https://doi.org/10.1007/s10661-024-12345-3
  98. Angel Negrete Velasco, Alicia Ellero, Stéphan Ramseier Gentile, Stéphane Zimmermann, Pascal Ramaciotti, Serge Stoll. Impact of a nanofiltration system on microplastic contamination in Geneva groundwater (Switzerland). Environmental Science and Pollution Research 2024, 31 (9) , 13512-13522. https://doi.org/10.1007/s11356-024-31940-y
  99. Hsuan-Cheng Lu, Julia L. Smith, Shima Ziajahromi, Frederic D.L. Leusch. Microplastics and other anthropogenic fibres in large apex shark species: Abundance, characteristics, and recommendations for future research. Chemosphere 2024, 349 , 140957. https://doi.org/10.1016/j.chemosphere.2023.140957
  100. Yonghao Sun, Jun Zhang, Zhoujie Jiang, Yi Wang, Peng Duan, Wei Min, Weicheng Zhang. Polystyrene microplastics enhance oxidative dissolution but suppress the aquatic acute toxicity of a commercial cadmium yellow pigment under simulated irradiation. Journal of Hazardous Materials 2024, 463 , 132881. https://doi.org/10.1016/j.jhazmat.2023.132881
Load more citations
Download PDF
Go to Environmental Science & Technology
Get e-Alerts
Get e-Alerts

Environmental Science & Technology

Cite this: Environ. Sci. Technol. 2018, 52, 18, 10230–10240
Click to copy citationCitation copied!
https://doi.org/10.1021/acs.est.8b01611
Published August 23, 2018

Copyright © 2018 American Chemical Society. This publication is licensed under CC-BY-NC-ND.

Article Views

21k

Altmetric

-

Citations

420
Learn about these metrics

Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.

Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.

The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.

  • Abstract

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 1

    Figure 1. Ingestion incidence and 95% confidence intervals recalculated from data provided in microplastic ingestion studies. Data are combined to obtain a “whole ocean” biota ingestion incidence value (○).

    High Resolution Image
    Download MS PowerPoint Slide

  • References

    This article references 88 other publications.

    1. 1
      GESAMP Sources, fate and effects of microplastics in the marine environment: part two of a global assessment; Kershaw, P. J., Rochman, C. M., eds.; IMO/FAO/UNESCO-IOC/UNIDO/WMO/IAEA/UN/ UNEP/UNDP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection; Rep. Stud. GESAMP, 2016; Vol. 93, p 220.
      There is no corresponding record for this reference.
    2. 2
      Wright, S. L.; Thompson, R. C.; Galloway, T. S. The physical impacts of microplastics on marine organisms: A review. Environ. Pollut. 2013, 178, 483– 492,  DOI: 10.1016/j.envpol.2013.02.031
      2
      The physical impacts of microplastics on marine organisms: A review
      Wright, Stephanie L.; Thompson, Richard C.; Galloway, Tamara S.
      Environmental Pollution (Oxford, United Kingdom) (2013), 178 (), 483-492CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      A review. Plastic debris at the micro-, and potentially also the nano-scale, are widespread in the environment. Microplastics have accumulated in oceans and sediments worldwide in recent years, with max. concns. reaching 100 000 particles m3. Due to their small size, microplastics may be ingested by low trophic fauna, with uncertain consequences for the health of the organism. This review focuses on marine invertebrates and their susceptibility to the phys. impacts of microplastic uptake. Some of the main points discussed are (1) an evaluation of the factors contributing to the bioavailability of microplastics including size and d.; (2) an assessment of the relative susceptibility of different feeding guilds; (3) an overview of the factors most likely to influence the phys. impacts of microplastics such as accumulation and translocation; and (4) the trophic transfer of microplastics. These findings are important in guiding future marine litter research and management strategies.
    3. 3
      Browne, M. A.; Galloway, T.; Thompson, R. Microplastic—an emerging contaminant of potential concern?. Integr. Environ. Assess. Manage. 2007, 3 (4), 559– 561,  DOI: 10.1002/ieam.5630030412
      There is no corresponding record for this reference.
    4. 4
      Chen, Q.; Reisser, J.; Cunsolo, S.; Kwadijk, C.; Kotterman, M.; Proietti, M.; Slat, B.; Ferrari, F. F.; Schwarz, A.; Levivier, A.; Yin, D.; Hollert, H.; Koelmans, A. A. Pollutants in Plastics within the North Pacific Subtropical Gyre. Environ. Sci. Technol. 2018, 52 (2), 446– 456,  DOI: 10.1021/acs.est.7b04682
      4
      Pollutants in Plastics within the North Pacific Subtropical Gyre
      Chen, Qiqing; Reisser, Julia; Cunsolo, Serena; Kwadijk, Christiaan; Kotterman, Michiel; Proietti, Maira; Slat, Boyan; Ferrari, Francesco F.; Schwarz, Anna; Levivier, Aurore; Yin, Daqiang; Hollert, Henner; Koelmans, Albert A.
      Environmental Science & Technology (2018), 52 (2), 446-456CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Here we report concns. of pollutants in floating plastics from the North Pacific accumulation zone (NPAC). We compared chem. concns. in plastics of different types and sizes, assessed ocean plastic potential risks using sediment quality criteria, and discussed the implications of our findings for bioaccumulation. Our results suggest that at least a fraction of the NPAC plastics is not in equil. with the surrounding seawater. For instance, "hard plastic" samples had significantly higher PBDE concns. than "nets and ropes" samples, and 29% of them had PBDE compn. similar to a widely used flame-retardant mixt. Our findings indicate that NPAC plastics may pose a chem. risk to organisms as 84% of the samples had at least one chem. exceeding sediment threshold effect levels. Furthermore, our surface trawls collected more plastic than biomass (180 times on av.), indicating that some NPAC organisms feeding upon floating particles may have plastic as a major component of their diets. If gradients for pollutant transfer from NPAC plastic to predators exist (as indicated by our fugacity ratio calcns.), plastics may play a role in transferring chems. to certain marine organisms.
    5. 5
      Lusher, A. L.; McHugh, M.; Thompson, R. C. Occurrence of microplastics in the gastrointestinal tract of pelagic and demersal fish from the English Channel. Mar. Pollut. Bull. 2013, 67 (1), 94– 99,  DOI: 10.1016/j.marpolbul.2012.11.028
      5
      Occurrence of microplastics in the gastrointestinal tract of pelagic and demersal fish from the English Channel
      Lusher, A. L.; McHugh, M.; Thompson, R. C.
      Marine Pollution Bulletin (2013), 67 (1-2), 94-99CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Microplastics are present in marine habitats worldwide and lab. studies show this material can be ingested, yet data on abundance in natural populations is limited. This study documents microplastics in 10 species of fish from the English Channel. 504 Fish were examd. and plastics found in the gastrointestinal tracts of 36.5%. All five pelagic species and all five demersal species had ingested plastic. Of the 184 fish that had ingested plastic the av. no. of pieces per fish was 1.90 ± 0.10. A total of 351 pieces of plastic were identified using FT-IR Spectroscopy; polyamide (35.6%) and the semi-synthetic cellulosic material, rayon (57.8%) were most common. There was no significant difference between the abundance of plastic ingested by pelagic and demersal fish. Hence, microplastic ingestion appears to be common, in relatively small quantities, across a range of fish species irresp. of feeding habitat. Further work is needed to establish the potential consequences.
    6. 6
      Foekema, E. M.; De Gruijter, C.; Mergia, M. T.; van Franeker, J. A.; Murk, A. J.; Koelmans, A. A. Plastic in North Sea Fish. Environ. Sci. Technol. 2013, 47 (15), 8818– 8824,  DOI: 10.1021/es400931b
      6
      Plastic in North Sea Fish
      Foekema, Edwin M.; De Gruijter, Corine; Mergia, Mekuria T.; van Franeker, Jan Andries; Murk, AlberTinka J.; Koelmans, Albert A.
      Environmental Science & Technology (2013), 47 (15), 8818-8824CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      To quantify the occurrence of ingested plastic in fish species caught at different geog. positions in the North Sea, and to test whether the fish condition is affected by ingestion of plastics, 1203 individual fish of seven common North Sea species were investigated: herring, gray gurnard, whiting, horse mackerel, haddock, atlantic mackerel, and cod. Plastic particles were found in 2.6% of the examd. fish and in five of the seven species. No plastics were found in gray gurnard and mackerel. In most cases, only one particle was found per fish, ranging in size from 0.04 to 4.8 mm. Only particles larger than 0.2 mm, being the diam. of the sieve used, were considered for the data analyses, resulting in a median particle size of 0.8 mm. The frequency of fish with plastic was significantly higher (5.4%) in the southern North Sea, than in the northern North Sea above 55°N (1.2%). The highest frequency (>33%) was found in cod from the English Channel. In addn., small fibers were initially detected in most of the samples, but their abundance sharply decreased when working under special clean air conditions. Therefore, these fibers were considered to be artifacts related to air born contamination and were excluded from the analyses. No relationship was found between the condition factor (size-wt. relationship) of the fish and the presence of ingested plastic particles.
    7. 7
      Neves, D.; Sobral, P.; Ferreira, J. L.; Pereira, T. Ingestion of microplastics by commercial fish off the Portuguese coast. Mar. Pollut. Bull. 2015, 101 (1), 119– 126,  DOI: 10.1016/j.marpolbul.2015.11.008
      7
      Ingestion of microplastics by commercial fish off the Portuguese coast
      Neves, Diogo; Sobral, Paula; Ferreira, Joana Lia; Pereira, Tania
      Marine Pollution Bulletin (2015), 101 (1), 119-126CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      The digestive tract contents of 263 individuals from 26 species of com. fish were examd. for microplastics. These were found in 17 species, corresponding to 19.8% of the fish of which 32.7% had ingested more than one microplastic. Of all the fish that ingested microplastics, 63.5% was benthic and 36.5% pelagic species. A total of 73 microplastics were recorded, 48 (65.8%) being fibers and 25 (34.2%) being fragments. Polymers were polypropylene, polyethylene, alkyd resin, rayon, polyester, nylon and acrylic. The mean of ingested microplastics was 0.27 ± 0.63 per fish, (n = 263). Pelagic fish ingested more particles and benthic fish ingested more fibers, but no significant differences were found. Fish with the highest no. of microplastics were from the mouth of the Tagus river. Scomber japonicus registered the highest mean of ingested microplastics, suggesting its potential as indicator species to monitor and investigate trends in ingested litter, in the MSFD marine regions.
    8. 8
      Mathalon, A.; Hill, P. Microplastic fibers in the intertidal ecosystem surrounding Halifax Harbor, Nova Scotia. Mar. Pollut. Bull. 2014, 81 (1), 69– 79,  DOI: 10.1016/j.marpolbul.2014.02.018
      8
      Microplastic fibers in the intertidal ecosystem surrounding Halifax Harbor, Nova Scotia
      Mathalon, Alysse; Hill, Paul
      Marine Pollution Bulletin (2014), 81 (1), 69-79CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Humans continue to increase the use and disposal of plastics by producing over 240 million tonnes per yr, polluting the oceans with persistent waste. The majority of plastic in the oceans are microplastics (<5 mm). In this study, the contamination of microplastic fibers was quantified in sediments from the intertidal zones of one exposed beach and two protected beaches along Nova Scotia's Eastern Shore. From the two protected beaches, polychaete worm fecal casts and live blue mussels (Mytilus edulis) were analyzed for microplastic content. Store-bought mussels from an aquaculture site were also analyzed. The av. microplastic abundance obsd. from 10 g sediment subsamples was between 20 and 80 fibers, with higher concns. at the high tide line from the exposed beach and at the low tide line from the protected beaches. Microplastic concns. from polychaete fecal casts resembled concns. quantified from low tide sediments. In two sep. mussel analyses, significantly more microplastics were enumerated in farmed mussels compared to wild ones.
    9. 9
      Romeo, T.; Pietro, B.; Pedà, C.; Consoli, P.; Andaloro, F.; Fossi, M. C. First evidence of presence of plastic debris in stomach of large pelagic fish in the Mediterranean Sea. Mar. Pollut. Bull. 2015, 95 (1), 358– 361,  DOI: 10.1016/j.marpolbul.2015.04.048
      9
      First evidence of presence of plastic debris in stomach of large pelagic fish in the Mediterranean Sea
      Romeo, Teresa; Pietro, Battaglia; Peda, Cristina; Consoli, Pierpaolo; Andaloro, Franco; Fossi, Maria Cristina
      Marine Pollution Bulletin (2015), 95 (1), 358-361CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      This study focuses, for the first time, on the presence of plastic debris in the stomach contents of large pelagic fish (Xiphias gladius, Thunnus thynnus and Thunnus alalunga) caught in the Mediterranean Sea between 2012 and 2013. Results highlighted the ingestion of plastics in the 18.2% of samples. The plastics ingested were microplastics (<5 mm), mesoplastics (5-25 mm) and macroplastics (>25 mm).These preliminary results represent an important initial phase in exploring two main ecotoxicol. aspects: (a) the assessment of the presence and impact of plastic debris on these large pelagic fish, and (b) the potential effects related to the transfer of contaminants on human health.
    10. 10
      Lusher, A. Microplastics in the Marine Environment: Distribution, Interactions and Effects. In Marine Anthropogenic Litter; Bergmann, M., Gutow, L., Klages, M., Eds.; Springer International Publishing: Cham, 2015; pp 245– 307.
      There is no corresponding record for this reference.
    11. 11
      Teuten, E. L.; Saquing, J. M.; Knappe, D. R. U.; Barlaz, M. A.; Jonsson, S.; Björn, A.; Rowland, S. J.; Thompson, R. C.; Galloway, T. S.; Yamashita, R.; Ochi, D.; Watanuki, Y.; Moore, C.; Viet, P. H.; Tana, T. S.; Prudente, M.; Boonyatumanond, R.; Zakaria, M. P.; Akkhavong, K.; Ogata, Y.; Hirai, H.; Iwasa, S.; Mizukawa, K.; Hagino, Y.; Imamura, A.; Saha, M.; Takada, H. Transport and release of chemicals from plastics to the environment and to wildlife. Philos. Trans. R. Soc., B 2009, 364 (1526), 2027– 2045,  DOI: 10.1098/rstb.2008.0284
      11
      Transport and release of chemicals from plastics to the environment and to wildlife
      Teuten, Emma L.; Saquing, Jovita M.; Knappe, Detlef R. U.; Barlaz, Morton A.; Jonsson, Susanne; Bjoern, Annika; Rowland, Steven J.; Thompson, Richard C.; Galloway, Tamara S.; Yamashita, Rei; Ochi, Daisuke; Watanuki, Yutaka; Moore, Charles; Viet, Pham Hung; Tana, Touch Seang; Prudente, Maricar; Boonyatumanond, Ruchaya; Zakaria, Mohamad P.; Akkhavong, Kongsap; Ogata, Yuko; Hirai, Hisashi; Iwasa, Satoru; Mizukawa, Kaoruko; Hagino, Yuki; Imamura, Ayako; Saha, Mahua; Takada, Hideshige
      Philosophical Transactions of the Royal Society, B: Biological Sciences (2009), 364 (1526), 2027-2045CODEN: PTRBAE; ISSN:0962-8436. (Royal Society)
      A review. Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain org. contaminants, including polychlorinated biphenyls (PCBs), polycyclic arom. hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2'-bis(p-chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concns. from sub ng g-1 to μg g-1. Some of these compds. are added during plastics manuf., while others adsorb from the surrounding seawater. Concns. of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calcns. and exptl. observations consistently show that polyethylene accumulates more org. contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a math. model using equil. partitioning and exptl. data have demonstrated the transfer of contaminants from plastic to organisms. A feeding expt. indicated that PCBs could transfer from contaminated plastics to streaked shearwater chicks. Plasticizers, other plastics additives and constitutional monomers also present potential threats in terrestrial environments because they can leach from waste disposal sites into groundwater and/or surface waters. Leaching and degrdn. of plasticizers and polymers are complex phenomena dependent on environmental conditions in the landfill and the chem. properties of each additive. Bisphenol A concns. in leachates from municipal waste disposal sites in tropical Asia ranged from sub μg l-1 to mg l-1 and were correlated with the level of economic development.
    12. 12
      Mato, Y.; Isobe, T.; Takada, H.; Kanehiro, H.; Ohtake, C.; Kaminuma, T. Plastic resin pellets as a transport medium for toxic chemicals in the marine environment. Environ. Sci. Technol. 2001, 35 (2), 318– 324,  DOI: 10.1021/es0010498
      12
      Plastic Resin Pellets as a Transport Medium for Toxic Chemicals in the Marine Environment
      Mato, Yukie; Isobe, Tomohiko; Takada, Hideshige; Kanehiro, Haruyuki; Ohtake, Chiyoko; Kaminuma, Tsuguchika
      Environmental Science and Technology (2001), 35 (2), 318-324CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Plastic resin pellets (small granules 0.1-0.5 cm diam.) are widely distributed in the ocean worldwide. They are an industrial raw material for the plastic industry and are unintentionally released to the environment during manufg. and transport. They are sometimes ingested by seabirds and other marine organisms; their adverse effects on organisms are a concern. In this, polychlorinated biphenyls (PCB), DDE, and nonylphenols (NP) were detected in polypropylene (PP) resin pellets collected from 4 Japanese coasts. Concns. of PCB (4-117 ng/g), DDE (0.16-3.1 ng/g), and NP (0.13-16 μg/g) varied among sample site. Concns. were comparable to those for suspended particles and bottom sediment collected from the same area as the pellets. Field adsorption expts. using PP virgin pellets demonstrated a significant, steady increase in PCB and DDE concns. throughout a 6-day expt., indicating the source of PCB and DDE is ambient seawater and that adsorption to pellet surfaces is the mechanism of enrichment. The major source of NP in the marine PP resin pellets was thought to be plastic additives and/or their degrdn. products. Comparison of PCB and DDE concns. in marine PP resin pellets with those in seawater suggested their high degree of accumulation (apparent adsorption coeff.: 105-106). The high accumulation potential suggested that plastic resin pellets serve as a transport medium and a potential source of toxic chems. in the marine environment.
    13. 13
      Diepens, N. J.; Koelmans, A. A. Accumulation of plastic debris and associated contaminants in aquatic food webs. Environ. Sci. Technol. 2018, 52, 8510– 8520,  DOI: 10.1021/acs.est.8b02515
      13
      Accumulation of Plastic Debris and Associated Contaminants in Aquatic Food Webs
      Diepens, Noel J.; Koelmans, Albert A.
      Environmental Science & Technology (2018), 52 (15), 8510-8520CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      The authors present a generic theor. model (MICROWEB) that simulates the transfer of microplastics and hydrophobic org. chems. (HOC) in food webs. The authors implemented the model for an Arctic case comprised of nine species including Atlantic cod and polar bear as top predator. The authors used the model to examine the effect of plastic ingestion on trophic transfer of microplastics and persistent HOCs (PCBs) and metabolizable HOCs (PAHs), spanning a wide range of hydrophobicities. Published data for values partition of PCBs and microplastics in the arctic area were used. In a scenario where HOCs in plastic and water are in equil., PCBs biomagnify less when more microplastic is ingested, because PCBs biomagnify less well from ingested plastic than from regular food. But PAHs biomagnify more when more microplastic is ingested, because plastic reduces the fraction of PAHs available for metabolization. The authors also explore nonequil. scenarios representative of additives that are leaching out, as well as sorbing HOCs, quant. showing how the above trends are strengthened and weakened, resp. The obsd. patterns were not very sensitive to modifications in the structure of the food web. The model can be used as a tool to assess prospective risks of exposure to microplastics and complex HOC mixts. for any food web, including those with relevance for human health.
    14. 14
      Cozar, A.; Echevarria, F.; Gonzalez-Gordillo, J. I.; Irigoien, X.; Ubeda, B.; Hernandez-Leon, S.; Palma, A. T.; Navarro, S.; Garcia-de-Lomas, J.; Ruiz, A.; Fernandez-de-Puelles, M. L.; Duarte, C. M. Plastic debris in the open ocean. Proc. Natl. Acad. Sci. U. S. A. 2014, 111 (28), 10239– 10244,  DOI: 10.1073/pnas.1314705111
      14
      Plastic debris in the open ocean
      Cozar, Andres; Echevarria, Fidel; Gonzalez-Gordillo, J. Ignacio; Irigoien, Xabier; Ubeda, Barbara; Hernandez-Leon, Santiago; Palma, Alvaro T.; Navarro, Sandra; Garcia-de-Lomas, Juan; Ruiz, Andrea; Fernandez-de-Puelles, Maria L.; Duarte, Carlos M.
      Proceedings of the National Academy of Sciences of the United States of America (2014), 111 (28), 10239-10244CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
      There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable d. However, the global load of plastic on the open ocean surface was estd. to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to det. the nature and significance of the impacts of plastic pollution in the ocean.
    15. 15
      Rochman, C. M.; Browne, M. A.; Underwood, A. J.; van Franeker, J. A.; Thompson, R. C. T.; Amaral-Zettler, L. A. The ecological impacts of marine debris: unraveling the demonstrated evidence from what is perceived. Ecology 2016, 97 (2), 302– 312,  DOI: 10.1890/14-2070.1
      15
      The ecological impacts of marine debris: unraveling the demonstrated evidence from what is perceived
      Rochman Chelsea M; Browne Mark Anthony; Underwood A J; van Franeker Jan A; Thompson Richard C; Amaral-Zettler Linda A
      Ecology (2016), 97 (2), 302-12 ISSN:0012-9658.
      Anthropogenic debris contaminates marine habitats globally, leading to several perceived ecological impacts. Here, we critically and systematically review the literature regarding impacts of debris from several scientific fields to understand the weight of evidence regarding the ecological impacts of marine debris. We quantified perceived and demonstrated impacts across several levels of biological organization that make up the ecosystem and found 366 perceived threats of debris across all levels. Two hundred and ninety-six of these perceived threats were tested, 83% of which were demonstrated. The majority (82%) of demonstrated impacts were due to plastic, relative to other materials (e.g., metals, glass) and largely (89%) at suborganismal levels (e.g., molecular, cellular, tissue). The remaining impacts, demonstrated at higher levels of organization (i.e., death to individual organisms, changes in assemblages), were largely due to plastic marine debris (> 1 mm; e.g., rope, straws, and fragments). Thus, we show evidence of ecological impacts from marine debris, but conclude that the quantity and quality of research requires improvement to allow the risk of ecological impacts of marine debris to be determined with precision. Still, our systematic review suggests that sufficient evidence exists for decision makers to begin to mitigate problematic plastic debris now, to avoid risk of irreversible harm.
    16. 16
      Besseling, E.; Foekema, E. M.; Van Franeker, J. A.; Leopold, M. F.; Kuhn, S.; Rebolledo, E. L. B.; Hesse, E.; Mielke, L.; Ijzer, J.; Kamminga, P.; Koelmans, A. A. Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae. Mar. Pollut. Bull. 2015, 95 (1), 248– 252,  DOI: 10.1016/j.marpolbul.2015.04.007
      16
      Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae
      Besseling, E.; Foekema, E. M.; Van Franeker, J. A.; Leopold, M. F.; Kuehn, S.; Bravo Rebolledo, E. L.; Hesse, E.; Mielke, L.; IJzer, J.; Kamminga, P.; Koelmans, A. A.
      Marine Pollution Bulletin (2015), 95 (1), 248-252CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water vols. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in intestines of a baleen whale (Megaptera novaeangliae). Contents of its gastrointestinal tract were sieved, dissolved in 10% potassium hydroxide and washed. From the remaining dried material, potential synthetic polymer particles were selected based on d. and appearance, and analyzed by Fourier transform IR (FTIR) spectroscopy. Several polymer types (polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, nylon) were found, in varying particle shapes: sheets, fragments and threads with a size of 1 mm to 17 cm. This diversity in polymer types and particle shapes, can be interpreted as a representation of the varying characteristics of marine plastic and the unselective way of ingestion by M. novaeangliae.
    17. 17
      Lusher, A. L.; Hernandez-Milian, G.; Berrow, S.; Rogan, E.; O’Connor, I. Incidence of marine debris in cetaceans stranded and bycaught in Ireland: Recent findings and a review of historical knowledge. Environ. Pollut. 2018, 232, 467– 476,  DOI: 10.1016/j.envpol.2017.09.070
      17
      Incidence of marine debris in cetaceans stranded and bycaught in Ireland: Recent findings and a review of historical knowledge
      Lusher, Amy L.; Hernandez-Milian, Gema; Berrow, Simon; Rogan, Emer; O'Connor, Ian
      Environmental Pollution (Oxford, United Kingdom) (2018), 232 (), 467-476CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      Interactions between marine mammals and plastic debris have been the focus of studies for many years. Examples of interactions include entanglement in discarded fishing items or the presence of ingested debris in digestive tracts. Plastics, including microplastics, are a form of marine debris globally distributed in coastal areas, oceanic waters and deep seas. Cetaceans which strand along the coast present a unique opportunity to study interactions between animals with macro- and microplastics. A combination of novel techniques and a review of historical data was used to complete an extensive study of cetaceans interacting with marine debris within Irish waters. Of the 25 species of marine mammals reported in Irish waters, at least 19 species were reported stranded between 1990 and 2015 (n = 2934). Two hundred and forty-one of the stranded cetaceans presented signs of possible entanglement or interactions with fisheries. Of this no., 52.7% were pos. identified as bycatch or as entangled in fisheries items, 26.6% were classified as mutilated and 20.7% could not be related to fisheries but showed signs of entanglement. In addn., 274 cetaceans were recorded as by-catch during observer programs targeting albacore tuna. Post-mortem examns. were carried out on a total of 528 stranded and bycaught individuals and 45 (8.5%) had marine debris in their digestive tracts: 21 contained macrodebris, 21 contained microdebris and three had both macro- and microdebris. Forty percent of the ingested debris were fisheries related items. All 21 individuals investigated with the novel method for microplastics contained microplastics, composed of fibers (83.6%) and fragments (16.4%). Deep diving species presented more incidences of macrodebris ingestion but it was not possible to investigate this relationship to ecol. habitat. More research on the plastic implications to higher trophic level organisms is required to understand the effects of these pollutants.
    18. 18
      Herzke, D.; Anker-Nilssen, T.; Nøst, T. H.; Götsch, A.; Christensen-Dalsgaard, S.; Langset, M.; Fangel, K.; Koelmans, A. A. Negligible Impact of Ingested Microplastics on Tissue Concentrations of Persistent Organic Pollutants in Northern Fulmars off Coastal Norway. Environ. Sci. Technol. 2016, 50 (4), 1924– 1933,  DOI: 10.1021/acs.est.5b04663
      There is no corresponding record for this reference.
    19. 19
      Koelmans, A. A. Modeling the Role of Microplastics in Bioaccumulation of Organic Chemicals to Marine Aquatic Organisms. A Critical Review. In Marine Anthropogenic Litter; Bergmann, M., Gutow, L., Klages, M., Eds.; Springer International Publishing: Cham, 2015; pp 309– 324.
      There is no corresponding record for this reference.
    20. 20
      Koelmans, A. A.; Besseling, E.; Wegner, A.; Foekema, E. M. Plastic as a Carrier of POPs to Aquatic Organisms: A Model Analysis. Environ. Sci. Technol. 2013, 47 (14), 7812– 7820,  DOI: 10.1021/es401169n
      20
      Plastic as a Carrier of POPs to Aquatic Organisms: A Model Analysis
      Koelmans, Albert A.; Besseling, Ellen; Wegner, Anna; Foekema, Edwin M.
      Environmental Science & Technology (2013), 47 (14), 7812-7820CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      It has been hypothesized that persistent org. pollutants (POPs) in microplastic may pose a risk to aquatic organisms. We develop and analyze a conceptual model that simulates the effects of plastic on bioaccumulation of POPs. The model accounts for diln. of exposure concn. by sorption of POPs to plastic (POP diln.), increased bioaccumulation by ingestion of plastic-contg. POPs (carrier), and decreased bioaccumulation by ingestion of clean plastic (cleaning). The model is parametrized for the lugworm Arenicola marina and evaluated against recently published bioaccumulation data for this species from lab. bioassays with polystyrene microplastic. Further scenarios include polyethylene microplastic, nanosized plastic, and open marine systems. Model anal. shows that plastic with low affinity for POPs such as polystyrene will have a marginal decreasing effect on bioaccumulation, governed by diln. For stronger sorbents such as polyethylene, the diln., carrier, and cleaning mechanism are more substantial. In closed lab. bioassay systems, diln. and cleaning dominate, leading to decreased bioaccumulation. Also in open marine systems a decrease is predicted due to a cleaning mechanism that counteracts biomagnification. However, the differences are considered too small to be relevant from a risk assessment perspective.
    21. 21
      Setälä, O.; Fleming-Lehtinen, V.; Lehtiniemi, M. Ingestion and transfer of microplastics in the planktonic food web. Environ. Pollut. 2014, 185 (0), 77– 83,  DOI: 10.1016/j.envpol.2013.10.013
      There is no corresponding record for this reference.
    22. 22
      Farrell, P.; Nelson, K. Trophic level transfer of microplastic: Mytilus edulis (L.) to Carcinus maenas (L.). Environ. Pollut. 2013, 177, 1– 3,  DOI: 10.1016/j.envpol.2013.01.046
      22
      Trophic level transfer of microplastic: Mytilus edulis (L.) to Carcinus maenas (L.)
      Farrell, Paul; Nelson, Kathryn
      Environmental Pollution (Oxford, United Kingdom) (2013), 177 (), 1-3CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      This study investigated the trophic transfer of microplastic from mussels to crabs. Mussels (Mytilus edulis) were exposed to 0.5 μm fluorescent polystyrene microspheres, then fed to crabs (Carcinus maenas). Tissue samples were then taken at intervals up to 21 days. The no. of microspheres in the hemolymph of the crabs was highest at 24 h (15 033 mL-1 ± SE 3146), and was almost gone after 21 days (267 mL-1 ± SE 120). The max. amt. of microspheres in the hemolymph was 0.04% of the amt. to which the mussels were exposed. Microspheres were also found in the stomach, hepatopancreas, ovary and gills of the crabs, in decreasing nos. over the trial period. This study is the first to show natural' trophic transfer of microplastic, and its translocation to hemolymph and tissues of a crab. This has implications for the health of marine organisms, the wider food web and humans.
    23. 23
      Wright, S. L.; Kelly, F. J. Plastic and Human Health: A Micro Issue?. Environ. Sci. Technol. 2017, 51 (12), 6634– 6647,  DOI: 10.1021/acs.est.7b00423
      23
      Plastic and Human Health: A Micro Issue?
      Wright, Stephanie L.; Kelly, Frank J.
      Environmental Science & Technology (2017), 51 (12), 6634-6647CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      A review. Microplastics are a pollutant of environmental concern. Their presence in food destined for human consumption and in air samples has been reported. Thus, microplastic exposure via diet or inhalation could occur, the human health effects of which are unknown. The current review article draws upon cross-disciplinary scientific literature to discuss and evaluate the potential human health impacts of microplastics and outlines urgent areas for future research. Key literature up to Sept. 2016 relating to bioaccumulation, particle toxicity, and chem. and microbial contaminants were critically examd. While this is an emerging field, complementary existing fields indicate potential particle, chem. and microbial hazards. If inhaled or ingested, microplastics may bioaccumulate and exert localized particle toxicity by inducing or enhancing an immune response. Chem. toxicity could occur due to the localized leaching of component monomers, endogenous additives, and adsorbed environmental pollutants. Chronic exposure is anticipated to be of greater concern due to the accumulative effect which could occur. This is expected to be dose-dependent, and a robust evidence-base of exposure levels is currently lacking. While there is potential for microplastics to impact human health, assessing current exposure levels and burdens is key. This information will guide future research into the potential mechanisms of toxicity and hence therein possible health effects.
    24. 24
      Filella, M. Questions of size and numbers in environmental research on microplastics: methodological and conceptual aspects. Environmental Chemistry 2015, 12 (5), 527– 538,  DOI: 10.1071/EN15012
      24
      Questions of size and numbers in environmental research on microplastics: methodological and conceptual aspects
      Filella, Montserrat
      Environmental Chemistry (2015), 12 (5), 527-538CODEN: ECNHAA; ISSN:1449-8979. (CSIRO Publishing)
      Environmental context Microplastics, either purposefully manufd. or formed by fragmentation of discarded 'end-of-life' macroplastic items, are accumulating in environmental compartments. As more and more data are collected on microplastics in the environment, discussion of two issues has become indispensable: (i) how reliable are the results in terms of the inherent capabilities and limitations of current methods used for sampling, counting and measuring microplastic particles; and (ii) how can the fate of microplastics be understood in the context of natural particles and colloids Abstr. A first important step in evaluating the impact of microplastic pollution in natural systems is assessing the reliability of the results obtained according to the inherent capabilities and limitations of the methods used for sampling, counting and measuring microplastic particles. This study, based on the crit. reading of 55 studies contg. quant. microplastic data in waters and sediments, is an attempt to analyze these issues in the light of existing knowledge in the field of natural colloid studies. Existing results are highly dependent on the sampling and methodol. procedure chosen and are essentially descriptive. Moreover, often they lack standardisation and adequate reporting of basic information such as the meaning of the size parameter measured. Colloid theory may provide the theor. background needed to explain microplastic behavior or, at least, to identify the parameters (e.g. d., surface characteristics, shape) that need to be known in order to gain a predictive knowledge of the subject. They are introduced and discussed. Finally, microplastics are not alone in environmental compartments. For this reason, when possible, published microplastic particle size distributions in natural waters have been quant. situated in the context of natural particles.
    25. 25
      Connors, K. A.; Dyer, S. D.; Belanger, S. E. Advancing the quality of environmental microplastic research. Environ. Toxicol. Chem. 2017, 36 (7), 1697– 1703,  DOI: 10.1002/etc.3829
      25
      Advancing the quality of environmental microplastic research
      Connors, Kristin A.; Dyer, Scott D.; Belanger, Scott E.
      Environmental Toxicology and Chemistry (2017), 36 (7), 1697-1703CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)
      Investigations into the environmental fate and effects of microplastics have been gaining momentum. Small, insol. polymeric particles are implicated by scientists in a wide variety of studies that are used to suggest a potential for widespread impacts in freshwater and marine pelagic and sediment environments. An exponential growth in scientific publications and an increase in regulatory attention have occurred. However, despite these efforts, the environmental hazard of these particles is still unknown. To evaluate the hazard of microplastics within a risk assessment context, we need a way to evaluate the quality of exptl. studies. We performed a thorough review of the quality and focus of environmental microplastic research, to understand the methodologies employed and how this may assist or distract from the ability of environmental risk assessors to evaluate microplastics. We provide guidance to improve the reliability and relevance of ecotoxicol. studies for regulatory and broader environmental assessments. Nine areas of needed improvement are identified and discussed. Important data gaps and exptl. limitations are highlighted. Environ Toxicol Chem 2017;9999:1-7. © 2017 SETAC.
    26. 26
      Hanvey, J. S.; Lewis, P. J.; Lavers, J. L.; Crosbie, N. D.; Pozo, K.; Clarke, B. O. A review of analytical techniques for quantifying microplastics in sediments. Anal. Methods 2017, 9 (9), 1369– 1383,  DOI: 10.1039/C6AY02707E
      There is no corresponding record for this reference.
    27. 27
      Vandermeersch, G.; Van Cauwenberghe, L.; Janssen, C. R.; Marques, A.; Granby, K.; Fait, G.; Kotterman, M. J. J.; Diogène, J.; Bekaert, K.; Robbens, J.; Devriese, L. A critical view on microplastic quantification in aquatic organisms. Environ. Res. 2015, 143, 46– 55,  DOI: 10.1016/j.envres.2015.07.016
      27
      A critical view on microplastic quantification in aquatic organisms
      Vandermeersch, Griet; Van Cauwenberghe, Lisbeth; Janssen, Colin R.; Marques, Antonio; Granby, Kit; Fait, Gabriella; Kotterman, Michiel J. J.; Diogene, Jorge; Bekaert, Karen; Robbens, Johan; Devriese, Lisa
      Environmental Research (2015), 143 (Part_B), 46-55CODEN: ENVRAL; ISSN:0013-9351. (Elsevier)
      Microplastics, plastic particles and fragments smaller than 5 mm, are ubiquitous in the marine environment. Ingestion and accumulation of microplastics have previously been demonstrated for diverse marine species ranging from zooplankton to bivalves and fish, implying the potential for microplastics to accumulate in the marine food web. In this way, microplastics can potentially impact food safety and human health. Although a few methods to quantify microplastics in biota have been described, no comparison and/or intercalibration of these techniques have been performed. Here we conducted a literature review on all available extn. and quantification methods. Two of these methods, involving wet acid destruction, were used to evaluate the presence of microplastics in field-collected mussels (Mytilus galloprovincialis) from three different "hotspot" locations in Europe (Po estuary, Italy; Tagus estuary, Portugal; Ebro estuary, Spain). An av. of 0.18±0.14 total microplastics g-1 w.w. for the Acid mix Method and 0.12±0.04 total microplastics g-1 w.w. for the Nitric acid Method was established. Addnl., in a pilot study an av. load of 0.13±0.14 total microplastics g-1 w.w. was recorded in com. mussels (Mytilus edulis and M. galloprovincialis) from five European countries (France, Italy, Denmark, Spain and The Netherlands). A detailed anal. and comparison of methods indicated the need for further research to develop a standardised operating protocol for microplastic quantification and monitoring.
    28. 28
      Wesch, C.; Bredimus, K.; Paulus, M.; Klein, R. Towards the suitable monitoring of ingestion of microplastics by marine biota: A review. Environ. Pollut. 2016, 218, 1200– 1208,  DOI: 10.1016/j.envpol.2016.08.076
      28
      Towards the suitable monitoring of ingestion of microplastics by marine biota: A review
      Wesch, Charlotte; Bredimus, Katja; Paulus, Martin; Klein, Roland
      Environmental Pollution (Oxford, United Kingdom) (2016), 218 (), 1200-1208CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      Monitoring plastic ingestion in marine biota is a difficult task, esp. regarding ubiquitous microplastics (particles of <5 mm). Due to their microscopic size, evidence for microplastic ingestion is often limited to lab. studies. The following review provides a comparison and assessment of different microplastic ingestion monitoring procedures. Emphasis is given to the most important steps of current monitoring practice: (1) selecting suitable indicator species, (2) sampling and sample processing, (3) anal. procedures and (4) the prevention of secondary contamination of the sample. Moreover, an overview on ingestion records of microplastics by different marine feeding guilds is presented, including filter, suspension and deposit feeders as well as predators and scavengers. Lastly, monitoring processes are addressed critically in terms of their suitability for achieving the aims of an appropriate monitoring program. Recommendations for future research priorities are presented with a focus on the necessity of standardized and comparable monitoring procedures in microplastic detection.
    29. 29
      Löder, M. G. J.; Gerdts, G. Methodology Used for the Detection and Identification of Microplastics - A Critical Appraisal. In Marine Anthropogenic Litter; Bergmann, M., Gutow, L., Klages, M., Eds.; Springer International Publishing: Berlin, 2015; pp 201– 227.
      There is no corresponding record for this reference.
    30. 30
      Klimisch, H. J.; Andreae, M.; Tillmann, U. A Systematic Approach for Evaluating the Quality of Experimental Toxicological and Ecotoxicological Data. Regul. Toxicol. Pharmacol. 1997, 25 (1), 1– 5,  DOI: 10.1006/rtph.1996.1076
      30
      A systematic approach for evaluating the quality of experimental toxicological and ecotoxicological data
      Klimisch, H.-J.; Andreae, M.; Tillmann, U.
      Regulatory Toxicology and Pharmacology (1997), 25 (1), 1-5CODEN: RTOPDW; ISSN:0273-2300. (Academic)
      The evaluation of the quality of data and their use in hazard and risk assessment as a systematic approach is described. Definitions are proposed for the reliability, relevance, and the adequacy of the data. Reliability is differentiated into 4 categories. Criteria relating to international testing stds. for categorizing reliability are developed. A systematic documentation of evaluating reliability esp. for use in the IUCLID database is proposed. This approach is intended to harmonize data evaluation processes worldwide. It may help the expert in subsequent assessments and should increase the clarity of evaluation.
    31. 31
      Kase, R.; Korkaric, M.; Werner, I.; Ågerstrand, M. Criteria for Reporting and Evaluating ecotoxicity Data (CRED): comparison and perception of the Klimisch and CRED methods for evaluating reliability and relevance of ecotoxicity studies. Environ. Sci. Eur. 2016, 28 (1), 7,  DOI: 10.1186/s12302-016-0073-x
      31
      Criteria for Reporting and Evaluating ecotoxicity Data (CRED): comparison and perception of the Klimisch and CRED methods for evaluating reliability and relevance of ecotoxicity studies
      Kase Robert; Werner Inge; Korkaric Muris; ¡ÑÜAgerstrand Marlene
      Environmental sciences Europe (2016), 28 (1), 7 ISSN:2190-4707.
      BACKGROUND: The regulatory evaluation of ecotoxicity studies for environmental risk and/or hazard assessment of chemicals is often performed using the method established by Klimisch and colleagues in 1997. The method was, at that time, an important step toward improved evaluation of study reliability, but lately it has been criticized for lack of detail and guidance, and for not ensuring sufficient consistency among risk assessors. RESULTS: A new evaluation method was thus developed: Criteria for Reporting and Evaluating ecotoxicity Data (CRED). The CRED evaluation method aims at strengthening consistency and transparency of hazard and risk assessment of chemicals by providing criteria and guidance for reliability and relevance evaluation of aquatic ecotoxicity studies. A two-phased ring test was conducted to compare and characterize the differences between the CRED and Klimisch evaluation methods. A total of 75 risk assessors from 12 countries participated. Results show that the CRED evaluation method provides a more detailed and transparent evaluation of reliability and relevance than the Klimisch method. Ring test participants perceived it to be less dependent on expert judgement, more accurate and consistent, and practical regarding the use of criteria and time needed for performing an evaluation. CONCLUSIONS: We conclude that the CRED evaluation method is a suitable replacement for the Klimisch method, and that its use may contribute to an improved harmonization of hazard and risk assessments of chemicals across different regulatory frameworks.
    32. 32
      Koelmans, A. A.; Besseling, E.; Foekema, E.; Kooi, M.; Mintenig, S.; Ossendorp, B. C.; Redondo-Hasselerharm, P. E.; Verschoor, A.; van Wezel, A. P.; Scheffer, M. Risks of Plastic Debris: Unravelling Fact, Opinion, Perception, and Belief. Environ. Sci. Technol. 2017, 51 (20), 11513– 11519,  DOI: 10.1021/acs.est.7b02219
      32
      Risks of Plastic Debris: Unravelling Fact, Opinion, Perception, and Belief
      Koelmans, Albert A.; Besseling, Ellen; Foekema, Edwin; Kooi, Merel; Mintenig, Svenja; Ossendorp, Bernadette C.; Redondo-Hasselerharm, Paula E.; Verschoor, Anja; van Wezel, Annemarie P.; Scheffer, Marten
      Environmental Science & Technology (2017), 51 (20), 11513-11519CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Researcher and media alarms caused plastic debris to be perceived as a major threat to humans and animals; however, although wasting plastics in the environment is clearly undesirable for aesthetic and economic reasons, actual environmental risks of different plastics and their assocd. chems. is largely unknown. This work showed how a systematic assessment of adverse outcome pathways based on ecol. relevant metrics for exposure and effect can bring risk assessment within reach. Results will help respond to the current public concern in a balanced way and allow policy-makers to take measures using scientifically sound reasons.
    33. 33
      Brown, L. D.; Cai, T. T.; DasGupta, A. Interval Estimation for a Binomial Proportion. Statistical Science 2001, 16 (2), 101– 117,  DOI: 10.1214/ss/1009213286
      There is no corresponding record for this reference.
    34. 34
      Kooi, M.; Nes, E. H. v.; Scheffer, M.; Koelmans, A. A. Ups and Downs in the Ocean: Effects of Biofouling on Vertical Transport of Microplastics. Environ. Sci. Technol. 2017, 51 (14), 7963– 7971,  DOI: 10.1021/acs.est.6b04702
      34
      Ups and Downs in the Ocean: Effects of Biofouling on Vertical Transport of Microplastics
      Kooi, Merel; Nes, Egbert H. van; Scheffer, Marten; Koelmans, Albert A.
      Environmental Science & Technology (2017), 51 (14), 7963-7971CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Recent studies suggest size-selective removal of small plastic particles from the ocean surface, an observation that remains unexplained. We studied one of the hypotheses regarding this size-selective removal: the formation of a biofilm on the microplastics (biofouling). We developed the first theor. model that is capable of simulating the effect of biofouling on the fate of microplastic. The model is based on settling, biofilm growth, and ocean depth profiles for light, water d., temp., salinity, and viscosity. Using realistic parameters, the model simulates the vertical transport of small microplastic particles over time, and predicts that the particles either float, sink to the ocean floor, or oscillate vertically, depending on the size and d. of the particle. The predicted size-dependent vertical movement of microplastic particles results in a max. concn. at intermediate depths. Consequently, relatively low abundances of small particles are predicted at the ocean surface, while at the same time these small particles may never reach the ocean floor. Our results hint at the fate of "lost" plastic in the ocean, and provide a start for predicting risks of exposure to microplastics for potentially vulnerable species living at these depths.
    35. 35
      Gall, S. C.; Thompson, R. C. The impact of debris on marine life. Mar. Pollut. Bull. 2015, 92 (1), 170– 179,  DOI: 10.1016/j.marpolbul.2014.12.041
      35
      The impact of debris on marine life
      Gall, S. C.; Thompson, R. C.
      Marine Pollution Bulletin (2015), 92 (1-2), 170-179CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Marine debris is listed among the major perceived threats to biodiversity, and is cause for particular concern due to its abundance, durability and persistence in the marine environment. An extensive literature search reviewed the current state of knowledge on the effects of marine debris on marine organisms. 340 original publications reported encounters between organisms and marine debris and 693 species. Plastic debris accounted for 92% of encounters between debris and individuals. Numerous direct and indirect consequences were recorded, with the potential for sublethal effects of ingestion an area of considerable uncertainty and concern. Comparison to the IUCN Red List highlighted that at least 17% of species affected by entanglement and ingestion were listed as threatened or near threatened. Hence where marine debris combines with other anthropogenic stressors it may affect populations, trophic interactions and assemblages.
    36. 36
      Claessens, M.; De Meester, S.; Van Landuyt, L.; De Clerck, K.; Janssen, C. R. Occurrence and distribution of microplastics in marine sediments along the Belgian coast. Mar. Pollut. Bull. 2011, 62 (10), 2199– 204,  DOI: 10.1016/j.marpolbul.2011.06.030
      36
      Occurrence and distribution of microplastics in marine sediments along the Belgian coast
      Claessens, Michiel; De Meester, Steven; Van Landuyt, Lieve; De Clerck, Karen; Janssen, Colin R.
      Marine Pollution Bulletin (2011), 62 (10), 2199-2204CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Plastic debris is known to undergo fragmentation at sea, which leads to the formation of microscopic particles of plastic; the so called microplastics'. Due to their buoyant and persistent properties, these microplastics have the potential to become widely dispersed in the marine environment through hydrodynamic processes and ocean currents. In this study, the occurrence and distribution of microplastics was investigated in Belgian marine sediments from different locations (coastal harbours, beaches and sublittoral areas). Particles were found in large nos. in all samples, showing the wide distribution of microplastics in Belgian coastal waters. The highest concns. were found in the harbours where total microplastic concns. of up to 390 particles kg-1 dry sediment were obsd., which is 15-50 times higher than reported max. concns. of other, similar study areas. The depth profile of sediment cores suggested that microplastic concns. on the beaches reflect the global plastic prodn. increase.
    37. 37
      Woodall, L. C.; Gwinnett, C.; Packer, M.; Thompson, R. C.; Robinson, L. F.; Paterson, G. L. J. Using a forensic science approach to minimize environmental contamination and to identify microfibres in marine sediments. Mar. Pollut. Bull. 2015, 95 (1), 40– 46,  DOI: 10.1016/j.marpolbul.2015.04.044
      37
      Using a forensic science approach to minimize environmental contamination and to identify microfibres in marine sediments
      Woodall, Lucy C.; Gwinnett, Claire; Packer, Margaret; Thompson, Richard C.; Robinson, Laura F.; Paterson, Gordon L. J.
      Marine Pollution Bulletin (2015), 95 (1), 40-46CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      There is growing evidence of extensive pollution of the environment by microplastic, with microfibres representing a large proportion of the microplastics seen in marine sediments. Since microfibres are ubiquitous in the environment, present in the lab. air and water, evaluating microplastic pollution is difficult. Incidental contamination is highly likely unless strict control measures are employed. Here we describe methods developed to minimize the amt. of incidental post-sampling contamination when quantifying marine microfibre pollution. We show that our protocol, adapted from the field of forensic fiber examn., reduces fiber abundance by 90% and enables the quick screening of fiber populations. These methods therefore allow an accurate est. of microplastics polluting marine sediments. In a case study from a series of samples collected on a research vessel, we use these methods to highlight the prevalence of microfibres as marine microplastics.
    38. 38
      Van Cauwenberghe, L.; Vanreusel, A.; Mees, J.; Janssen, C. R. Microplastic pollution in deep-sea sediments. Environ. Pollut. 2013, 182, 495– 499,  DOI: 10.1016/j.envpol.2013.08.013
      38
      Microplastic pollution in deep-sea sediments
      Van Cauwenberghe, Lisbeth; Vanreusel, Ann; Mees, Jan; Janssen, Colin R.
      Environmental Pollution (Oxford, United Kingdom) (2013), 182 (), 495-499CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      Microplastics are small plastic particles (<1 mm) originating from the degrdn. of larger plastic debris. These microplastics have been accumulating in the marine environment for decades and have been detected throughout the water column and in sublittoral and beach sediments worldwide. However, up to now, it has never been established whether microplastic presence in sediments is limited to accumulation hot spots such as the continental shelf, or whether they are also present in deep-sea sediments. Here we show, for the first time ever, that microplastics have indeed reached the most remote of marine environments: the deep sea. We found plastic particles sized in the micrometre range in deep-sea sediments collected at four locations representing different deep-sea habitats ranging in depth from 1100 to 5000 m. Our results demonstrate that microplastic pollution has spread throughout the world's seas and oceans, into the remote and largely unknown deep sea.
    39. 39
      Setälä, O.; Norkko, J.; Lehtiniemi, M. Feeding type affects microplastic ingestion in a coastal invertebrate community. Mar. Pollut. Bull. 2016, 102 (1), 95– 101,  DOI: 10.1016/j.marpolbul.2015.11.053
      39
      Feeding type affects microplastic ingestion in a coastal invertebrate community
      Setala, Outi; Norkko, Joanna; Lehtiniemi, Maiju
      Marine Pollution Bulletin (2016), 102 (1), 95-101CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Marine litter is one of the problems marine ecosystems face at present, coastal habitats and food webs being the most vulnerable as they are closest to the sources of litter. A range of animals (bivalves, free swimming crustaceans and benthic, deposit-feeding animals), of a coastal community of the northern Baltic Sea were exposed to relatively low concns. of 10 μm microbeads. The expt. was carried out as a small scale mesocosm study to mimic natural habitat. The beads were ingested by all animals in all exptl. concns. (5, 50 and 250 beads mL- 1). Bivalves (Mytilus trossulus, Macoma balthica) contained significantly higher amts. of beads compared with the other groups. Free-swimming crustaceans ingested more beads compared with the benthic animals that were feeding only on the sediment surface. Ingestion of the beads was concluded to be the result of particle concn., feeding mode and the encounter rate in a patchy environment.
    40. 40
      Redondo-Hasselerharm, P. E.; Falahudin, D.; Peeters, E. T. H. M.; Koelmans, A. A. Microplastic Effect Thresholds for Freshwater Benthic Macroinvertebrates. Environ. Sci. Technol. 2018, 52 (4), 2278– 2286,  DOI: 10.1021/acs.est.7b05367
      40
      Microplastic Effect Thresholds for Freshwater Benthic Macroinvertebrates
      Redondo-Hasselerharm, Paula E.; Falahudin, Dede; Peeters, Edwin T. H. M.; Koelmans, Albert A.
      Environmental Science & Technology (2018), 52 (4), 2278-2286CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Now that microplastics have been detected in lakes, rivers, and estuaries all over the globe, evaluating their effects on biota has become an urgent research priority. This is the first study that aims at detg. the effect thresholds for a battery of six freshwater benthic macroinvertebrates with different species traits, using a wide range of microplastic concns. Standardized 28 days single species bioassays were performed under environmentally relevant exposure conditions using polystyrene microplastics (20-500 μm) mixed with sediment at concns. ranging from 0 to 40% sediment dry wt. (dw). Microplastics caused no effects on the survival of Gammarus pulex, Hyalella azteca, Asellus aquaticus, Sphaerium corneum, and Tubifex spp. and no effects were found on the reprodn. of Lumbriculus variegatus. No significant differences in growth were found for H. azteca, A. aquaticus, S. corneum, L. variegatus, and Tubifex spp. However, G. pulex showed a significant redn. in growth (EC10 = 1.07% sediment dw) and microplastic uptake was proportional with microplastic concns. in sediment. These results indicate that although the risks of environmentally realistic concns. of microplastics may be low, they still may affect the biodiversity and the functioning of aquatic communities which after all also depend on the sensitive species.
    41. 41
      Davison, P.; Asch, R. G. Plastic ingestion by mesopelagic fishes in the North Pacific Subtropical Gyre. Mar. Ecol.: Prog. Ser. 2011, 432, 173– 180,  DOI: 10.3354/meps09142
      There is no corresponding record for this reference.
    42. 42
      OSPAR request on development of a common monitoring protocol for plastic particles in fish stomachs and selected shellfish on the basis of existing fish disease surveys. IICES Advice 2015, 1, 1– 6.
      There is no corresponding record for this reference.
    43. 43
      Cannon, S. M. E.; Lavers, J. L.; Figueiredo, B. Plastic ingestion by fish in the Southern Hemisphere: A baseline study and review of methods. Mar. Pollut. Bull. 2016, 107, 286– 291,  DOI: 10.1016/j.marpolbul.2016.03.057
      There is no corresponding record for this reference.
    44. 44
      Jabeen, K.; Su, L.; Li, J.; Yang, D.; Tong, C.; Mu, J.; Shi, H. Microplastics and mesoplastics in fish from coastal and fresh waters of China. Environ. Pollut. 2017, 221, 141– 149,  DOI: 10.1016/j.envpol.2016.11.055
      44
      Microplastics and mesoplastics in fish from coastal and fresh waters of China
      Jabeen, Khalida; Su, Lei; Li, Jiana; Yang, Dongqi; Tong, Chunfu; Mu, Jingli; Shi, Huahong
      Environmental Pollution (Oxford, United Kingdom) (2017), 221 (), 141-149CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      Plastic pollution is a growing global concern. In the present study, we investigated plastic pollution in 21 species of sea fish and 6 species of freshwater fish from China. All of the species were found to ingest micro- or mesoplastics. The av. abundance of microplastics varied from 1.1 to 7.2 items by individual and 0.2-17.2 items by gram. The av. abundance of mesoplastics varied from 0.2 to 3.0 items by individual and 0.1-3.9 items by gram. Microplastics were abundant in 26 species, accounting for 55.9-92.3% of the total no. of plastics items in each species. Thamnaconus septentrionalis contained the highest abundance of microplastics (7.2 items/individual). The av. abundance of plastics in sea benthopelagic fishes was significantly higher than in freshwater benthopelagic fishes by items/individual. The plastics were dominanted by fiber in shape, transparent in color and cellophane in compn. The proportion of plastics in the stomach to the intestines showed great variation in different species, ranging from 0.5 to 1.9 by items/individual. The stomach of Harpodon nehereus and intestines of Pampus cinereus contained the highest no. of plastics, (3.3) and (2.7), resp., by items/individual. Our results suggested that plastic pollution was widespread in the investigated fish species and showed higher abundance in comparison with worldwide studies. The ingestion of plastics in fish was closely related to the habitat and gastrointestinal tract structure. We highly recommend that the entire gastrointestinal tract and digestion process be used in future investigations of plastic pollution in fish.
    45. 45
      MSFD (Technical Subgroup on Marine Litter). Guidance on Monitoring of Marine Litter in European Seas , 2013.
      There is no corresponding record for this reference.
    46. 46
      Hermsen, E.; Pompe, R.; Besseling, E.; Koelmans, A. A. Detection of low numbers of microplastics in North Sea fish using strict quality assurance criteria. Mar. Pollut. Bull. 2017, 122 (1), 253– 258,  DOI: 10.1016/j.marpolbul.2017.06.051
      There is no corresponding record for this reference.
    47. 47
      Bellas, J.; Martínez-Armental, J.; Martínez-Cámara, A.; Besada, V.; Martínez-Gómez, C. Ingestion of microplastics by demersal fish from the Spanish Atlantic and Mediterranean coasts. Mar. Pollut. Bull. 2016, 109 (1), 55– 60,  DOI: 10.1016/j.marpolbul.2016.06.026
      47
      Ingestion of microplastics by demersal fish from the Spanish Atlantic and Mediterranean coasts
      Bellas, Juan; Martinez-Armental, Jose; Martinez-Camara, Ariana; Besada, Victoria; Martinez-Gomez, Concepcion
      Marine Pollution Bulletin (2016), 109 (1), 55-60CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Microplastic pollution has received increased attention over the last few years. This study documents microplastic ingestion in three com. relevant demersal fish species from the Spanish Atlantic and Mediterranean coasts, the lesser spotted dogfish Scyliorhinus canicula, the European hake Merluccius merluccius and the red mullet Mullus barbatus. Overall 212 fish were examd., 72 dogfish, 12 hakes and 128 red mullets. The percentage of fish with microplastics was 17.5% (15.3% dogfish, 18.8% red mullets and 16.7% hakes), averaging 1.56 ± 0.5 items per fish, and the size of the microplastics ranged from 0.38 to 3.1 mm. These fish species are used currently as biomonitors for marine pollution monitoring within the Spanish Marine Pollution Monitoring Program (SMP), and may be as well suitable candidates for monitoring spatial and temporal trends of ingested litter. The data presented here represent a baseline for the implementation of the Marine Strategy Framework Directive descriptor 10 in Spain.
    48. 48
      Lusher, A. L.; O’Donnell, C.; Officer, R.; O’Connor, I. Microplastic interactions with North Atlantic mesopelagic fish. ICES J. Mar. Sci. 2016, 73 (4), 1214– 1225,  DOI: 10.1093/icesjms/fsv241
      There is no corresponding record for this reference.
    49. 49
      Courtene-Jones, W.; Quinn, B.; Murphy, F.; Gary, S. F.; Narayanaswamy, B. E. Optimisation of enzymatic digestion and validation of specimen preservation methods for the analysis of ingested microplastics. Anal. Methods 2017, 9, 1437– 1445,  DOI: 10.1039/C6AY02343F
      49
      Optimisation of enzymatic digestion and validation of specimen preservation methods for the analysis of ingested microplastics
      Courtene-Jones, Winnie; Quinn, Brian; Murphy, Fionn; Gary, Stefan F.; Narayanaswamy, Bhavani E.
      Analytical Methods (2017), 9 (9), 1437-1445CODEN: AMNEGX; ISSN:1759-9679. (Royal Society of Chemistry)
      Microplastics are considered to be a widespread environmental contaminant. Due to their small size microplastics have the potential to be ingested by a range of aquatic organisms which mistake them for a food source and can suffer adverse impacts as a result. Development of standardised methods is imperative to provide reliable and meaningful data when analyzing microplastic ingestion by marine fauna. A range of proteolytic digestive enzymes (trypsin, papain and collagenase) were tested to establish optimum digestion efficacy of biol. samples and assess the effects of enzymes on microplastics; addnl. the applicability of freezing and formaldehyde followed by ethanol as specimen preservation techniques for microplastic research was investigated. Of the enzymes investigated, trypsin yielded the greatest digestive efficacy based on wt. redn. (88% ± 2.52 S.D.) at the lowest concn. (0.3125%) with no obsd. impacts on microplastics. Enumeration of microplastics from wild collected Mytilus edulis revealed mean nos. of 1.05 ± 0.66 S.D. (min.) to 4.44 ± 3.03 S.D. (max.) microplastic particles per g wet wt. mussel tissue depending on location. There was no significant difference based on preservation method on the quantification of ingested microplastics and no detrimental impacts were obsd. on the microplastics directly. Enzymic digestion using trypsin therefore provides a suitable, time and cost effective method to ext. microplastics from M. edulis. Furthermore the preservation methods did not have detrimental effects on microplastics, serving to highlight the suitability of biol. samples preserved either way for future inquiries into ingested microplastics.
    50. 50
      Desforges, J.-P. W.; Galbraith, M.; Ross, P. S. Ingestion of Microplastics by Zooplankton in the Northeast Pacific Ocean. Arch. Environ. Contam. Toxicol. 2015, 69 (3), 320– 330,  DOI: 10.1007/s00244-015-0172-5
      50
      Ingestion of Microplastics by Zooplankton in the Northeast Pacific Ocean
      Desforges, Jean-Pierre W.; Galbraith, Moira; Ross, Peter S.
      Archives of Environmental Contamination and Toxicology (2015), 69 (3), 320-330CODEN: AECTCV; ISSN:0090-4341. (Springer)
      Microplastics are increasingly recognized as being widespread in the world's oceans, but relatively little is known about ingestion by marine biota. In light of the potential for microplastic fibers and fragments to be taken up by small marine organisms, we examd. plastic ingestion by two foundation species near the base of North Pacific marine food webs, the calanoid copepod Neocalanus cristatus and the euphausiid Euphausia pacifia. We developed an acid digestion method to assess plastic ingestion by individual zooplankton and detected microplastics in both species. Encounter rates resulting from ingestion were 1 particle/every 34 copepods and 1/every 17 euphausiids (euphausiids > copepods; p = 0.01). Consistent with differences in the size selection of food between these two zooplankton species, the ingested particle size was greater in euphausiids (816 ± 108 μm) than in copepods (556 ± 149 μm) (p = 0.014). The contribution of ingested microplastic fibers to total plastic decreased with distance from shore in euphausiids (r2 = 70, p = 0.003), corresponding to patterns in our previous observations of microplastics in seawater samples from the same locations. This first evidence of microplastic ingestion by marine zooplankton indicate that species at lower trophic levels of the marine food web are mistaking plastic for food, which raises fundamental questions about potential risks to higher trophic level species. One concern is risk to salmon: We est. that consumption of microplastic-contg. zooplankton will lead to the ingestion of 2-7 microplastic particles/day by individual juvenile salmon in coastal British Columbia, and ≤91 microplastic particles/day in returning adults.
    51. 51
      Murray, F.; Cowie, P. R. Plastic contamination in the decapod crustacean Nephrops norvegicus (Linnaeus, 1758). Mar. Pollut. Bull. 2011, 62 (6), 1207– 1217,  DOI: 10.1016/j.marpolbul.2011.03.032
      51
      Plastic contamination in the decapod crustacean Nephrops norvegicus (Linnaeus, 1758)
      Murray, Fiona; Cowie, Phillip Rhys
      Marine Pollution Bulletin (2011), 62 (6), 1207-1217CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      The aim of this study was to det. the extent Nephrops consumes plastics in the Clyde Sea and if this intake occurs through their diet. Plastic contamination was found to be high in Nephrops, 83% of the animals sampled contained plastics (predominately filaments) in their stomachs. Tightly tangled balls of plastic strands were found in 62% of the animals studied but were least prevalent in animals which had recently moulted. No significant difference in plastic load was obsd. between males and females. Raman spectroscopy indicated that some of the microfilaments identified from gut contents could be sourced to fishing waste. Nephrops fed fish seeded with strands of polypropylene rope were found to ingest but not to excrete the strands. The fishery for Norway lobster, Nephrops norvegicus, is the most valuable in Scotland and the high prevalence of plastics in Nephrops may have implications for the health of the stock.
    52. 52
      Boerger, C. M.; Lattin, G. L.; Moore, S. L.; Moore, C. J. Plastic ingestion by planktivorous fishes in the North Pacific Central Gyre. Mar. Pollut. Bull. 2010, 60 (12), 2275– 2278,  DOI: 10.1016/j.marpolbul.2010.08.007
      52
      Plastic ingestion by planktivorous fishes in the North Pacific Central Gyre
      Boerger, Christiana M.; Lattin, Gwendolyn L.; Moore, Shelly L.; Moore, Charles J.
      Marine Pollution Bulletin (2010), 60 (12), 2275-2278CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      A significant amt. of marine debris has accumulated in the North Pacific Central Gyre (NPCG). The effects on larger marine organisms have been documented through cases of entanglement and ingestion; however, little is known about the effects on lower trophic level marine organisms. This study is the first to document ingestion and quantify the amt. of plastic found in the gut of common planktivorous fish in the NPCG. From Feb. 11 to 14, 2008, 11 neuston samples were collected by manta trawl in the NPCG. Plastic from each trawl and fish stomach was counted and weighed and categorized by type, size class and color. Approx. 35% of the fish studied had ingested plastic, averaging 2.1 pieces per fish. Addnl. studies are needed to det. the residence time of ingested plastics and their effects on fish health and the food chain implications.
    53. 53
      Karlsson, T. M.; Vethaak, A. D.; Almroth, B. C.; Ariese, F.; van Velzen, M.; Hassellöv, M.; Leslie, H. A. Screening for microplastics in sediment, water, marine invertebrates and fish: Method development and microplastic accumulation. Mar. Pollut. Bull. 2017, 122 (1), 403– 408,  DOI: 10.1016/j.marpolbul.2017.06.081
      53
      Screening for microplastics in sediment, water, marine invertebrates and fish: Method development and microplastic accumulation
      Karlsson, Therese M.; Vethaak, A. Dick; Almroth, Bethanie Carney; Ariese, Freek; van Velzen, Martin; Hasselloev, Martin; Leslie, Heather A.
      Marine Pollution Bulletin (2017), 122 (1-2), 403-408CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Measurements of microplastics in biota and abiotic matrixes are key elements of exposure and risk assessments for this emerging environmental pollutant. We investigated the abundance of microplastics in field-collected biota, sediment and water. An improved sediment extn. method, based on d. sepn. was developed. For anal. of microplastics in biota we found that an adapted enzymic digestion protocol using proteinase K performed best, with a 97% recovery of spiked plastic particles and no obsd. degrdn. effects on the plastics in subsequent Raman anal. Field anal. revealed that 8 of 9 tested invertebrate species from the North Sea and 68% of analyzed individuals of brown trout (Salmo trutta) from the Swedish West Coast had microplastics in them. Based on the no. of plastic particles per kg d.w. the microplastic concns. found in mussels were approx. a thousand-fold higher compared to those in sediment and surface water samples from the same location.
    54. 54
      Torre, M.; Digka, N.; Anastasopoulou, A.; Tsangaris, C.; Mytilineou, C. Anthropogenic microfibres pollution in marine biota. A new and simple methodology to minimize airborne contamination. Mar. Pollut. Bull. 2016, 113 (1), 55– 61,  DOI: 10.1016/j.marpolbul.2016.07.050
      There is no corresponding record for this reference.
    55. 55
      Liboiron, M.; Liboiron, F.; Wells, E.; Richárd, N.; Zahara, A.; Mather, C.; Bradshaw, H.; Murichi, J. Low plastic ingestion rate in Atlantic cod (Gadus morhua) from Newfoundland destined for human consumption collected through citizen science methods. Mar. Pollut. Bull. 2016, 113 (1), 428– 437,  DOI: 10.1016/j.marpolbul.2016.10.043
      There is no corresponding record for this reference.
    56. 56
      Devriese, L. I.; van der Meulen, M. D.; Maes, T.; Bekaert, K.; Paul-Pont, I.; Frère, L.; Robbens, J.; Vethaak, A. D. Microplastic contamination in brown shrimp (Crangon crangon, Linnaeus 1758) from coastal waters of the Southern North Sea and Channel area. Mar. Pollut. Bull. 2015, 98 (1), 179– 187,  DOI: 10.1016/j.marpolbul.2015.06.051
      56
      Microplastic contamination in brown shrimp (Crangon crangon, Linnaeus 1758) from coastal waters of the Southern North Sea and Channel area
      Devriese, Lisa I.; van der Meulen, Myra D.; Maes, Thomas; Bekaert, Karen; Paul-Pont, Ika; Frere, Laura; Robbens, Johan; Vethaak, A. Dick
      Marine Pollution Bulletin (2015), 98 (1-2), 179-187CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      This study assessed the capability of Crangon crangon (L.), an ecol. and com. important crustacean, of consuming plastics as an opportunistic feeder. We therefore detd. the microplastic content of shrimp in shallow water habitats of the Channel area and Southern part of the North Sea. Synthetic fibers ranging from 200 μm up to 1000 μm size were detected in 63% of the assessed shrimp and an av. value of 0.68 ± 0.55 microplastics/g w. w. (1.23 ± 0.99 microplastics/shrimp) was obtained for shrimp in the sampled area. The assessment revealed no spatial patterns in plastic ingestion, but temporal differences were reported. The microplastic uptake was significantly higher in Oct. compared to March. The results suggest that microplastics >20 μm are not able to translocate into the tissues.
    57. 57
      Wesch, C.; Elert, A. M.; Wörner, M.; Braun, U.; Klein, R.; Paulus, M. Assuring quality in microplastic monitoring: About the value of clean-air devices as essentials for verified data. Sci. Rep. 2017, 7 (1), 5424,  DOI: 10.1038/s41598-017-05838-4
      57
      Assuring quality in microplastic monitoring: About the value of clean-air devices as essentials for verified data
      Wesch Charlotte; Worner Manuel; Klein Roland; Paulus Martin; Elert Anna Maria; Braun Ulrike
      Scientific reports (2017), 7 (1), 5424 ISSN:.
      Avoiding aerial microfibre contamination of environmental samples is essential for reliable analyses when it comes to the detection of ubiquitous microplastics. Almost all laboratories have contamination problems which are largely unavoidable without investments in clean-air devices. Therefore, our study supplies an approach to assess background microfibre contamination of samples in the laboratory under particle-free air conditions. We tested aerial contamination of samples indoor, in a mobile laboratory, within a laboratory fume hood and on a clean bench with particles filtration during the examining process of a fish. The used clean bench reduced aerial microfibre contamination in our laboratory by 96.5%. This highlights the value of suitable clean-air devices for valid microplastic pollution data. Our results indicate, that pollution levels by microfibres have been overestimated and actual pollution levels may be many times lower. Accordingly, such clean-air devices are recommended for microplastic laboratory applications in future research work to significantly lower error rates.
    58. 58
      Rummel, C. D.; Löder, M. G. J.; Fricke, N. F.; Lang, T.; Griebeler, E. M.; Janke, M.; Gerdts, G. Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea. Mar. Pollut. Bull. 2016, 102 (1), 134– 141,  DOI: 10.1016/j.marpolbul.2015.11.043
      58
      Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea
      Rummel, Christoph D.; Loeder, Martin G. J.; Fricke, Nicolai F.; Lang, Thomas; Griebeler, Eva-Maria; Janke, Michael; Gerdts, Gunnar
      Marine Pollution Bulletin (2016), 102 (1), 134-141CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Plastic ingestion by marine biota has been reported for a variety of different taxa. In this study, we investigated 290 gastrointestinal tracts of demersal (cod, dab and flounder) and pelagic fish species (herring and mackerel) from the North and Baltic Sea for the occurrence of plastic ingestion. In 5.5% of all investigated fishes, plastic particles were detected, with 74% of all particles being in the microplastic (< 5 mm) size range. The polymer types of all found particles were analyzed by means of Fourier transform IR (FT-IR) spectroscopy. Almost 40% of the particles consisted of polyethylene (PE). In 3.4% of the demersal and 10.7% of the pelagic individuals, plastic ingestion was recorded, showing a significantly higher ingestion frequency in the pelagic feeders. The condition factor K was calcd. to test differences in the fitness status between individuals with and without ingested plastic, but no direct effect was detected.
    59. 59
      Davidson, K.; Dudas, S. E. Microplastic Ingestion by Wild and Cultured Manila Clams (Venerupis philippinarum) from Baynes Sound, British Columbia. Arch. Environ. Contam. Toxicol. 2016, 71 (2), 147– 156,  DOI: 10.1007/s00244-016-0286-4
      59
      Microplastic Ingestion by Wild and Cultured Manila Clams (Venerupis philippinarum) from Baynes Sound, British Columbia
      Davidson, Katie; Dudas, Sarah E.
      Archives of Environmental Contamination and Toxicology (2016), 71 (2), 147-156CODEN: AECTCV; ISSN:0090-4341. (Springer)
      Microplastics, plastic particles <5 mm, are an emerging concern in aquatic ecosystems. Because microplastics are small, they are available to many filter-feeding organisms, which can then be consumed by higher trophic level organisms, including humans. This study documents the quantity of microplastics present in wild and cultured Manila clams (Venerupis philippinarum). Three active shellfish farms and three ref. beaches (i.e., non-shellfish farm sites) in Baynes Sound, British Columbia were chosen to examine the microplastic concns. in wild and cultured Manila clams. Microplastics were isolated using a nitric acid digestion technique and enumerated from 54 clams (27 farmed and 27 non-farmed). Qual. attributes, such as color and microplastic type (fiber, fragment, or film) also were recorded. There was no significant difference (F = 1.29; df = 1,4; P = 0.289) between microplastic concns. in cultured and wild clams. Microplastic concns. ranged from 0.07 to 5.47 particles/g (from ref. beach and shellfish farm clams, resp.). Fibers were the dominant microplastic (90 %); colorless and dark gray fibers were the most common colors obsd. (36 and 26 %, resp.). Although this indicates that microplastics are definitely present in seafood consumed by humans, shellfish aquaculture operations do not appear to be increasing microplastic concns. in farmed clams in this region.
    60. 60
      Van Cauwenberghe, L.; Janssen, C. R. Microplastics in bivalves cultured for human consumption. Environ. Pollut. 2014, 193, 65– 70,  DOI: 10.1016/j.envpol.2014.06.010
      60
      Microplastics in bivalves cultured for human consumption
      Van Cauwenberghe, Lisbeth; Janssen, Colin R.
      Environmental Pollution (Oxford, United Kingdom) (2014), 193 (), 65-70CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      Microplastics are present throughout the marine environment and ingestion of these plastic particles (<1 mm) has been demonstrated in a lab. setting for a wide array of marine organisms. Here, we investigate the presence of microplastics in two species of com. grown bivalves: Mytilus edulis and Crassostrea gigas. Microplastics were recovered from the soft tissues of both species. At time of human consumption, M. edulis contains on av. 0.36 ± 0.07 particles g-1 (wet wt.), while a plastic load of 0.47 ± 0.16 particles g-1 ww was detected in C. gigas. As a result, the annual dietary exposure for European shellfish consumers can amt. to 11,000 microplastics per yr. The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estg. microplastic toxicity, estns. of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible.
    61. 61
      Löder, M. G. J.; Imhof, H. K.; Ladehoff, M.; Löschel, L. A.; Lorenz, C.; Mintenig, S.; Piehl, S.; Primpke, S.; Schrank, I.; Laforsch, C.; Gerdts, G. Enzymatic purification of microplastics in environmental samples. Environ. Sci. Technol. 2017, 51 (24), 14283– 14292,  DOI: 10.1021/acs.est.7b03055
      61
      Enzymatic Purification of Microplastics in Environmental Samples
      Loder Martin G J; Ladehoff Maike; Lorenz Claudia; Mintenig Svenja; Primpke Sebastian; Gerdts Gunnar; Imhof Hannes K; Loschel Lena A; Piehl Sarah; Schrank Isabella; Laforsch Christian
      Environmental science & technology (2017), 51 (24), 14283-14292 ISSN:.
      Micro-Fourier transform infrared (micro-FTIR) spectroscopy and Raman spectroscopy enable the reliable identification and quantification of microplastics (MPs) in the lower micron range. Since concentrations of MPs in the environment are usually low, the large sample volumes required for these techniques lead to an excess of coenriched organic or inorganic materials. While inorganic materials can be separated from MPs using density separation, the organic fraction impedes the ability to conduct reliable analyses. Hence, the purification of MPs from organic materials is crucial prior to conducting an identification via spectroscopic techniques. Strong acidic or alkaline treatments bear the danger of degrading sensitive synthetic polymers. We suggest an alternative method, which uses a series of technical grade enzymes for purifying MPs in environmental samples. A basic enzymatic purification protocol (BEPP) proved to be efficient while reducing 98.3 ± 0.1% of the sample matrix in surface water samples. After showing a high recovery rate (84.5 ± 3.3%), the BEPP was successfully applied to environmental samples from the North Sea where numbers of MPs range from 0.05 to 4.42 items m(-3). Experiences with different environmental sample matrices were considered in an improved and universally applicable version of the BEPP, which is suitable for focal plane array detector (FPA)-based micro-FTIR analyses of water, wastewater, sediment, biota, and food samples.
    62. 62
      Dehaut, A.; Cassone, A.-L.; Frère, L.; Hermabessiere, L.; Himber, C.; Rinnert, E.; Rivière, G.; Lambert, C.; Soudant, P.; Huvet, A.; Duflos, G.; Paul-Pont, I. Microplastics in seafood: Benchmark protocol for their extraction and characterization. Environ. Pollut. 2016, 215, 223– 233,  DOI: 10.1016/j.envpol.2016.05.018
      62
      Microplastics in seafood: Benchmark protocol for their extraction and characterization
      Dehaut, Alexandre; Cassone, Anne-Laure; Frere, Laura; Hermabessiere, Ludovic; Himber, Charlotte; Rinnert, Emmanuel; Riviere, Gilles; Lambert, Christophe; Soudant, Philippe; Huvet, Arnaud; Duflos, Guillaume; Paul-Pont, Ika
      Environmental Pollution (Oxford, United Kingdom) (2016), 215 (), 223-233CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      Pollution of the oceans by microplastics (<5 mm) represents a major environmental problem. To date, a limited no. of studies have investigated the level of contamination of marine organisms collected in situ. For extn. and characterization of microplastics in biol. samples, the crucial step is the identification of solvent(s) or chem.(s) that efficiently dissolve org. matter without degrading plastic polymers for their identification in a time and cost effective way. Most published papers, as well as OSPAR recommendations for the development of a common monitoring protocol for plastic particles in fish and shellfish at the European level, use protocols contg. nitric acid to digest the biol. tissues, despite reports of polyamide degrdn. with this chem. In the present study, six existing approaches were tested and their effects were compared on up to 15 different plastic polymers, as well as their efficiency in digesting biol. matrixes. Plastic integrity was evaluated through microscopic inspection, weighing, pyrolysis coupled with gas chromatog. and mass spectrometry, and Raman spectrometry before and after digestion. Tissues from mussels, crabs and fish were digested before being filtered on glass fiber filters. Digestion efficiency was evaluated through microscopical inspection of the filters and detn. of the relative removal of org. matter content after digestion. Five out of the six tested protocols led to significant degrdn. of plastic particles and/or insufficient tissue digestion. The protocol using a KOH 10% soln. and incubation at 60 °C during a 24 h period led to an efficient digestion of biol. tissues with no significant degrdn. on all tested polymers, except for cellulose acetate. This protocol appeared to be the best compromise for extn. and later identification of microplastics in biol. samples and should be implemented in further monitoring studies to ensure relevance and comparison of environmental and seafood product quality studies.
    63. 63
      Munno, K.; Helm, P. A.; Jackson, D. A.; Rochman, C.; Sims, A. Impacts of temperature and selected chemical digestion methods on microplastic particles. Environ. Toxicol. Chem. 2018, 37 (1), 91– 98,  DOI: 10.1002/etc.3935
      63
      Impacts of temperature and selected chemical digestion methods on microplastic particles
      Munno, Keenan; Helm, Paul A.; Jackson, Donald A.; Rochman, Chelsea; Sims, Alina
      Environmental Toxicology and Chemistry (2018), 37 (1), 91-98CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)
      Alk. and wet peroxide oxidn. chem. digestion techniques used to ext. microplastics from org. matrixes were assessed for recoveries and for impacts on ability to identify polymer types. Methods using wet peroxide oxidn. generated enough heat to result in the complete loss of some types of microplastic particles, and boiling tests confirmed that temps. >70 °C were responsible for the losses. Fourier transform IR spectroscopy (FT-IR) confirmed minimal alteration of the recovered polymers by the applied methods.
    64. 64
      Kühn, S.; van Werven, B.; van Oyen, A.; Meijboom, A.; Bravo Rebolledo, E. L.; van Franeker, J. A. The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms. Mar. Pollut. Bull. 2017, 115 (1–2), 86– 90,  DOI: 10.1016/j.marpolbul.2016.11.034
      64
      The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms
      Kuehn, Susanne; van Werven, Bernike; van Oyen, Albert; Meijboom, Andre; Bravo Rebolledo, Elisa L.; van Franeker, Jan A.
      Marine Pollution Bulletin (2017), 115 (1-2), 86-90CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      In studies of plastic ingestion by marine wildlife, visual sepn. of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solns. to dissolve org. materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irresp. of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) soln., with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solns. can be a useful approach in general quant. studies of plastic ingestion by marine wildlife.
    65. 65
      Cole, M.; Webb, H.; Lindeque, P.; Fileman, E. S.; Halsband, C.; Galloway, T. S. Isolation of microplastics in biota-rich seawater samples and marine organisms. Sci. Rep. 2015, 4 (4528), 1– 8,  DOI: 10.1038/srep04528
      There is no corresponding record for this reference.
    66. 66
      Catarino, A. I.; Thompson, R.; Sanderson, W.; Henry, T. B. Development and optimization of a standard method for extraction of microplastics in mussels by enzyme digestion of soft tissues. Environ. Toxicol. Chem. 2017, 36 (4), 947– 951,  DOI: 10.1002/etc.3608
      66
      Development and optimisation of a standard method for extraction of microplastics in mussels by enzyme digestion of soft tissues
      Catarino, Ana I.; Thompson, Richard; Sanderson, William; Henry, Theodore B.
      Environmental Toxicology and Chemistry (2017), 36 (4), 947-951CODEN: ETOCDK; ISSN:0730-7268. (Wiley-Blackwell)
      We compared procedures for digestion of mussel soft tissues and extn. of microplastics (MPs). Complete tissue digestion was achieved with 1M NaOH, 35% HNO3 and by 0.1 UHb/mL protease, but use of HNO3 caused unacceptable destruction of some MPs. Recovery of MPs spiked into mussels was similar (93 ± 10%) for NaOH and enzyme digestions. We recommend use of industrial enzymes based on digestion efficiency, MP recovery and avoidance of caustic chems. This article is protected by copyright. All rights reserved.
    67. 67
      Law, K. L.; Moret-Ferguson, S. E.; Goodwin, D. S.; Zettler, E. R.; De Force, E.; Kukulka, T.; Proskurowski, G. Distribution of Surface Plastic Debris in the Eastern Pacific Ocean from an 11-Year Data Set. Environ. Sci. Technol. 2014, 48 (9), 4732– 4738,  DOI: 10.1021/es4053076
      67
      Distribution of Surface Plastic Debris in the Eastern Pacific Ocean from an 11-Year Data Set
      Law, Kara Lavender; Moret-Ferguson, Skye E.; Goodwin, Deborah S.; Zettler, Erik R.; DeForce, Emelia; Kukulka, Tobias; Proskurowski, Giora
      Environmental Science & Technology (2014), 48 (9), 4732-4738CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      We present an extensive survey of floating plastic debris in the eastern North and South Pacific Oceans from more than 2500 plankton net tows conducted between 2001 and 2012. From these data we defined an accumulation zone (25 to 41°N, 130 to 180°W) in the North Pacific subtropical gyre that closely corresponds to centers of accumulation resulting from the convergence of ocean surface currents predicted by several oceanog. numerical models. Maximum plastic concns. from individual surface net tows exceeded 106 pieces km-2, with concns. decreasing with increasing distance from the predicted center of accumulation. Outside the North Pacific subtropical gyre the median plastic concn. was 0 pieces km-2. We were unable to detect a robust temporal trend in the data set, perhaps because of confounded spatial and temporal variability. Large spatiotemporal variability in plastic concn. causes order of magnitude differences in summary statistics calcd. over short time periods or in limited geog. areas. Utilizing all available plankton net data collected in the eastern Pacific Ocean (17.4°S to 61.0°N; 85.0 to 180.0°W) since 1999, we estd. a min. of 21 290 t of floating microplastic.
    68. 68
      Eriksen, M.; Mason, S.; Wilson, S.; Box, C.; Zellers, A.; Edwards, W.; Farley, H.; Amato, S. Microplastic pollution in the surface waters of the Laurentian Great Lakes. Mar. Pollut. Bull. 2013, 77 (1–2), 177– 82,  DOI: 10.1016/j.marpolbul.2013.10.007
      68
      Microplastic pollution in the surface waters of the Laurentian Great Lakes
      Eriksen, Marcus; Mason, Sherri; Wilson, Stiv; Box, Carolyn; Zellers, Ann; Edwards, William; Farley, Hannah; Amato, Stephen
      Marine Pollution Bulletin (2013), 77 (1-2), 177-182CODEN: MPNBAZ; ISSN:0025-326X. (Elsevier Ltd.)
      Neuston samples were collected at 21 stations during an ∼700 nautical mile (∼1300 km) expedition in July 2012 in the Laurentian Great Lakes of the United States using a 333 μm mesh manta trawl and analyzed for plastic debris. Although the av. abundance was approx. 43,000 microplastic particles/km2, station 20, downstream from two major cities, contained over 466,000 particles/km2, greater than all other stations combined. SEM anal. detd. nearly 20% of particles less than 1 mm, which were initially identified as microplastic by visual observation, were aluminum silicate from coal ash. Many microplastic particles were multi-colored spheres, which were compared to, and are suspected to be, microbeads from consumer products contg. microplastic particles of similar size, shape, texture and compn. The presence of microplastics and coal ash in these surface samples, which were most abundant where lake currents converge, are likely from nearby urban effluent and coal burning power plants.
    69. 69
      Imhof, H. K.; Laforsch, C.; Wiesheu, A. C.; Schmid, J.; Anger, P. M.; Niessner, R.; Ivleva, N. P. Pigments and plastic in limnetic ecosystems: A qualitative and quantitative study on microparticles of different size classes. Water Res. 2016, 98, 64– 74,  DOI: 10.1016/j.watres.2016.03.015
      69
      Pigments and plastic in limnetic ecosystems: A qualitative and quantitative study on microparticles of different size classes
      Imhof, Hannes K.; Laforsch, Christian; Wiesheu, Alexandra C.; Schmid, Johannes; Anger, Philipp M.; Niessner, Reinhard; Ivleva, Natalia P.
      Water Research (2016), 98 (), 64-74CODEN: WATRAG; ISSN:0043-1354. (Elsevier Ltd.)
      Recently, macroplastic (>5 mm) and esp. microplastic (<5 mm) particles have been reported as emerging contaminants in marine and limnetic ecosystems. Their coloration is gained by the addn. of pigments to the polymer blend which is the major component of the resp. product. However, color is also a feature of paint and coatings whereby the pigment is the major component. Once abraded from a surface, paint particles may enter the environment via similar pathways as microplastic particles. So far no detailed studies of microplastic particles (pigmented and non-pigmented) as well as paint particles have been performed focusing on very small microparticles (1-50 μm), in either marine or limnetic ecosystems. Using Raman microspectroscopy with a spatial resoln. down to 1 μm, we report a remarkable increase in the occurrence of (pigmented) microplastic particles below 500 μm. Among those, most particles were found at a size of ∼130 μm in a freshwater ecosystem (subalpine Lake Garda, Italy). Moreover, our qual. and quant. analyses revealed that the no. of paint microparticles significantly increased below the size range of 50 μm due to their brittleness (the smallest detected paint particle had a size of 4 μm). Inductively coupled plasma mass spectrometry measurements showed that both colored particles found in nature as well as virgin particles contain a high variety of metals such as cadmium, lead and copper. These additives may elicit adverse effects in biota ingesting these microparticles, thus paints and assocd. compds. may act as formerly overlooked contaminants in freshwater ecosystems.
    70. 70
      Peters, C. A.; Thomas, P. A.; Rieper, K. B.; Bratton, S. P. Foraging preferences influence microplastic ingestion by six marine fish species from the Texas Gulf Coast. Mar. Pollut. Bull. 2017, 124 (1), 82– 88,  DOI: 10.1016/j.marpolbul.2017.06.080
      There is no corresponding record for this reference.
    71. 71
      Remy, F.; Collard, F.; Gilbert, B.; Compère, P.; Eppe, G.; Lepoint, G. When Microplastic Is Not Plastic: The Ingestion of Artificial Cellulose Fibers by Macrofauna Living in Seagrass Macrophytodetritus. Environ. Sci. Technol. 2015, 49 (18), 11158– 11166,  DOI: 10.1021/acs.est.5b02005
      71
      When Microplastic Is Not Plastic: The Ingestion of Artificial Cellulose Fibers by Macrofauna Living in Seagrass Macrophytodetritus
      Remy, Francois; Collard, France; Gilbert, Bernard; Compere, Philippe; Eppe, Gauthier; Lepoint, Gilles
      Environmental Science & Technology (2015), 49 (18), 11158-11166CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      Dead leaves of the Neptune grass, Posidonia oceanica (L.) Delile, in the Mediterranean coastal zone, are colonized by an abundant detritivorous invertebrate community that is heavily predated by fishes. This community was sampled in August 2011, Nov. 2011, and March 2012 at 2 different sites in the Calvi Bay (Corsica). Ingested artificial fibers (AFs) of various sizes and colors were found in 27.6% of the digestive tracts of the 9 dominant species regardless of their trophic level or taxon. No seasonal, spatial, size, or species-specific significant differences were revealed; suggesting that invertebrates ingest AFs at const. rates. Results showed that, in the gut contents of invertebrates, varying by trophic level, and across trophic levels, the overall ingestion of AFs was low (∼1 fiber per organism). Raman spectroscopy revealed that the ingested AFs were composed of viscose, an artificial, cellulose-based polymer. Most of these AFs also appeared to have been colored by industrial dyes. Two dyes were identified: Direct Blue 22 and Direct Red 28. The latter is known for being carcinogenic for vertebrates, potentially causing environmental problems for the P. oceanica litter community. Techniques such as Raman spectroscopy are necessary to study the particles compn., instead of relying on fragment size or color to identify the particles ingested by animals.
    72. 72
      Käppler, A.; Windrich, F.; Loder, M. G. J.; Malanin, M.; Fischer, D.; Labrenz, M.; Eichhorn, K. J.; Voit, B. Identification of microplastics by FTIR and Raman microscopy: a novel silicon filter substrate opens the important spectral range below 1300 cm(−1) for FTIR transmission measurements. Anal. Bioanal. Chem. 2015, 407 (22), 6791– 6801,  DOI: 10.1007/s00216-015-8850-8
      72
      Identification of microplastics by FTIR and Raman microscopy: a novel silicon filter substrate opens the important spectral range below 1300 cm(-1) for FTIR transmission measurements
      Kappler Andrea; Windrich Frank; Loder Martin G J; Malanin Mikhail; Fischer Dieter; Labrenz Matthias; Eichhorn Klaus-Jochen; Voit Brigitte
      Analytical and bioanalytical chemistry (2015), 407 (22), 6791-801 ISSN:.
      The presence of microplastics in aquatic ecosystems is a topical problem and leads to the need of appropriate and reliable analytical methods to distinctly identify and to quantify these particles in environmental samples. As an example transmission, Fourier transform infrared (FTIR) imaging can be used to analyze samples directly on filters without any visual presorting, when the environmental sample was afore extracted, purified, and filtered. However, this analytical approach is strongly restricted by the limited IR transparency of conventional filter materials. Within this study, we describe a novel silicon (Si) filter substrate produced by photolithographic microstructuring, which guarantees sufficient transparency for the broad mid-infrared region of 4000-600 cm(-1). This filter type features holes with a diameter of 10 μm and exhibits adequate mechanical stability. Furthermore, it will be shown that our Si filter substrate allows a distinct identification of the most common microplastics, polyethylene (PE), and polypropylene (PP), in the characteristic fingerprint region (1400-600 cm(-1)). Moreover, using the Si filter substrate, a differentiation of microparticles of polyesters having quite similar chemical structure, like polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), is now possible, which facilitates a visualization of their distribution within a microplastic sample by FTIR imaging. Finally, this Si filter can also be used as substrate for Raman microscopy-a second complementary spectroscopic technique-to identify microplastic samples.
    73. 73
      Fries, E.; Dekiff, J. H.; Willmeyer, J.; Nuelle, M. T.; Ebert, M.; Remy, D. Identification of polymer types and additives in marine microplastic particles using pyrolysis-GC/MS and scanning electron microscopy. Environmental Science-Processes & Impacts 2013, 15 (10), 1949– 1956,  DOI: 10.1039/c3em00214d
      There is no corresponding record for this reference.
    74. 74
      Dümichen, E.; Eisentraut, P.; Bannick, C. G.; Barthel, A.-K.; Senz, R.; Braun, U. Fast identification of microplastics in complex environmental samples by a thermal degradation method. Chemosphere 2017, 174, 572– 584,  DOI: 10.1016/j.chemosphere.2017.02.010
      74
      Fast identification of microplastics in complex environmental samples by a thermal degradation method
      Duemichen, Erik; Eisentraut, Paul; Bannick, Claus Gerhard; Barthel, Anne-Kathrin; Senz, Rainer; Braun, Ulrike
      Chemosphere (2017), 174 (), 572-584CODEN: CMSHAF; ISSN:0045-6535. (Elsevier Ltd.)
      In order to det. the relevance of microplastic particles in various environmental media, comprehensive investigations are needed. However, no anal. method exists for fast identification and quantification. At present, optical spectroscopy methods like IR and RAMAN imaging are used. Due to their time consuming procedures and uncertain extrapolation, reliable monitoring is difficult. For analyzing polymers Py-GC-MS is a std. method. However, due to a limited sample amt. of about 0.5 mg it is not suited for anal. of complex sample mixts. like environmental samples. Therefore, we developed a new thermoanal. method as a first step for identifying microplastics in environmental samples. A sample amt. of about 20 mg, which assures the homogeneity of the sample, is subjected to complete thermal decompn. The specific degrdn. products of the resp. polymer are adsorbed on a solid-phase adsorber and subsequently analyzed by thermal desorption gas chromatog. mass spectrometry. For certain identification, the specific degrdn. products for the resp. polymer were selected first. Afterwards real environmental samples from the aquatic (three different rivers) and the terrestrial (bio gas plant) systems were screened for microplastics. Mainly polypropylene (PP), polyethylene (PE) and polystyrene (PS) were identified for the samples from the bio gas plant and PE and PS from the rivers. However, this was only the first step and quantification measurements will follow.
    75. 75
      Fischer, M.; Scholz-Böttcher, B. M. Simultaneous Trace Identification and Quantification of Common Types of Microplastics in Environmental Samples by Pyrolysis-Gas Chromatography–Mass Spectrometry. Environ. Sci. Technol. 2017, 51 (9), 5052– 5060,  DOI: 10.1021/acs.est.6b06362
      75
      Simultaneous Trace Identification and Quantification of Common Types of Microplastics in Environmental Samples by Pyrolysis-Gas Chromatography-Mass Spectrometry
      Fischer, Marten; Scholz-Boettcher, Barbara M.
      Environmental Science & Technology (2017), 51 (9), 5052-5060CODEN: ESTHAG; ISSN:0013-936X. (American Chemical Society)
      The content of microplastics (MP) in the environment is constantly growing. Since the environmental relevance, particularly bioavailability, rises with decreasing particle size, the knowledge of the MP proportion in habitats and organisms is of gaining importance. The reliable recognition of MP particles is limited and underlies substantial uncertainties. Therefore spectroscopically methods are necessary to ensure the plastic nature of isolated particles, det. the polymer type and obtain particle count related quant. data. In this study Curie-Point pyrolysis-gas chromatog.-mass spectrometry combined with thermochemolysis is shown to be an excellent anal. tool to simultaneously identify and optionally quantify MP in environmental samples on a polymer specific mass related trace level. The method is independent of any optical preselection or particle appearance. For this purpose polymer characteristic pyrolysis products and their indicative fragment ions were used to analyze eight common types of plastics. Further aspects of calibration, recoveries, and potential matrix effects are discussed. The method is exemplarily applied on selected fish samples after an enzymic-chem. pretreatment. This new approach with mass-related results is complementary to established FT-IR and Raman methods providing particle counts of individual polymer particles.
    76. 76
      Löder, M. G. J.; Kuczera, M.; Mintenig, S.; Lorenz, C.; Gerdts, G. Focal plane array detector-based micro-Fourier-transform infrared imaging for the analysis of microplastics in environmental samples. Environmental Chemistry 2015, 12 (5), 563– 581,  DOI: 10.1071/EN14205
      There is no corresponding record for this reference.
    77. 77
      Mintenig, S. M.; Bauerlein, P. S.; Koelmans, A. A.; Dekker, S. C.; van Wezel, A. P. Closing the gap between small and smaller: towards a framework to analyse nano- and microplastics in aqueous environmental samples. Environ. Sci.: Nano 2018, 5, 1640– 1649,  DOI: 10.1039/C8EN00186C
      77
      Closing the gap between small and smaller: towards a framework to analyse nano- and microplastics in aqueous environmental samples
      Mintenig, S. M.; Baeuerlein, P. S.; Koelmans, A. A.; Dekker, S. C.; van Wezel, A. P.
      Environmental Science: Nano (2018), 5 (7), 1640-1649CODEN: ESNNA4; ISSN:2051-8161. (Royal Society of Chemistry)
      Measuring concns. and sizes of micro- and nanoplastics in the environment is essential to assess the risks plastic particles could pose. Microplastics have been detected globally in a variety of aquatic ecosystems. The detn. of nanoplastics, however, is lagging behind due to higher methodol. challenges. Here, we propose a framework that can consistently det. a broad spectrum of plastic particle sizes in aquatic environmental samples. Anal. evidence is provided as proof of principle. FTIR microscopy is applied to detect microplastics. Nanoplastics are studied using field-flow-fractionation and pyrolysis GC-MS that gives information on the particle sizes and polymer types. Pyrolysis GC-MS is shown to be promising for the detection of nanoplastics in environmental samples as a mass of approx. 100 ng is required to identify polystyrene. Pre-concg. nanoplastics by crossflow ultrafiltration enables polystyrene to be identified when the original concn. in an aq. sample is >20μg L-1. Finally, we present an approach to est. polymer masses based on the two-dimensional microplastic shapes recorded during the anal. with FTIR microscopy. Our suite of techniques demonstrates that anal. of the entire size spectrum of plastic debris is feasible.
    78. 78
      Tanaka, K.; Takada, H. Microplastic fragments and microbeads in digestive tracts of planktivorous fish from urban coastal waters. Sci. Rep. 2016, 6, 34351,  DOI: 10.1038/srep34351
      78
      Microplastic fragments and microbeads in digestive tracts of planktivorous fish from urban coastal waters
      Tanaka, Kosuke; Takada, Hideshige
      Scientific Reports (2016), 6 (), 34351CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)
      We investigated microplastics in the digestive tracts of 64 Japanese anchovy (Engraulis japonicus) sampled in Tokyo Bay. Plastic was detected in 49 out of 64 fish (77%), with 2.3 pieces on av. and up to 15 pieces per individual. All of the plastics were identified by Fourier transform IR spectroscopy. Most were polyethylene (52.0%) or polypropylene (43.3%). Most of the plastics were fragments (86.0%), but 7.3% were beads, some of which were microbeads, similar to those found in facial cleansers. Eighty percent of the plastics ranged in size from 150 μm to 1000 μm, smaller than the reported size range of floating microplastics on the sea surface, possibly because the subsurface foraging behavior of the anchovy reflected the different size distribution of plastics between surface waters and subsurface waters. Engraulis spp. are important food for many humans and other organisms around the world. Our observations further confirm that microplastics have infiltrated the marine ecosystem, and that humans may be exposed to them. Because microplastics retain hazardous chems., increase in fish chem. exposure by the ingested plastics is of concern. Such exposure should be studied and compared with that in the natural diet.
    79. 79
      Wesch, C.; Barthel, A. K.; Braun, U.; Klein, R.; Paulus, M. No microplastics in benthic eelpout (Zoarces viviparus): An urgent need for spectroscopic analyses in microplastic detection. Environ. Res. 2016, 148, 36– 38,  DOI: 10.1016/j.envres.2016.03.017
      79
      No microplastics in benthic eelpout (Zoarces viviparus): An urgent need for spectroscopic analyses in microplastic detection
      Wesch, Charlotte; Barthel, Anne-Kathrin; Braun, Ulrike; Klein, Roland; Paulus, Martin
      Environmental Research (2016), 148 (), 36-38CODEN: ENVRAL; ISSN:0013-9351. (Elsevier)
      Monitoring the ingestion of microplastics is challenging and suitable detection techniques are insufficiently used. Thus, misidentifying natural for synthetic microfibres cannot be avoided. As part of a framework to monitor the ingestion of microplastics in eelpout, this short report addresses the accurate identification of microfibres. We show that, following visual inspections, putatively synthetic microfibres are indeed of natural origin, as ascertained by spectrometric analyses. Consequently, we call for an inclusion of spectroscopic techniques in standardized microplastic monitoring schemes.
    80. 80
      Li, J.; Yang, D.; Li, L.; Jabeen, K.; Shi, H. Microplastics in commercial bivalves from China. Environ. Pollut. 2015, 207, 190– 195,  DOI: 10.1016/j.envpol.2015.09.018
      80
      Microplastics in commercial bivalves from China
      Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong
      Environmental Pollution (Oxford, United Kingdom) (2015), 207 (), 190-195CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      We investigated microplastic pollution in 9 com. bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The no. of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on av. 10.5 items/g and exhibited the highest levels of microplastics by wt. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33-84% of the total microplastics calcd. by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in com. bivalves from China. More intensive investigations on microplastics should be conducted in seafood.
    81. 81
      Murphy, F.; Russell, M.; Ewins, C.; Quinn, B. The uptake of macroplastic & microplastic by demersal & pelagic fish in the Northeast Atlantic around Scotland. Mar. Pollut. Bull. 2017, 122 (1), 353– 359,  DOI: 10.1016/j.marpolbul.2017.06.073
      There is no corresponding record for this reference.
    82. 82
      Nadal, M. A.; Alomar, C.; Deudero, S. High levels of microplastic ingestion by the semipelagic fish bogue Boops boops (L.) around the Balearic Islands. Environ. Pollut. 2016, 214, 517– 523,  DOI: 10.1016/j.envpol.2016.04.054
      82
      High levels of microplastic ingestion by the semipelagic fish bogue Boops boops (L.) around the Balearic Islands
      Nadal, M. A.; Alomar, C.; Deudero, S.
      Environmental Pollution (Oxford, United Kingdom) (2016), 214 (), 517-523CODEN: ENPOEK; ISSN:0269-7491. (Elsevier Ltd.)
      For the first time this study reports on the presence of microplastics (1 nm to <5 mm) in the gastrointestinal tracts of small semipelagic fish (Boops boops) in the Balearic Islands (Mediterranean Sea) from March to May 2014. The results show microplastic ingestion in 68% of full stomach samples with an av. of 3.75 items per fish. Only filament type microplastics were obsd. in B. boops full gastrointestinal tracts. The frequency of occurrence of microplastics was high, with values ranging from 42% to 80%, in comparison to the other ingested items. Spatial variability among locations is high, which suggests that this type of contamination is ubiquitously distributed and originates from multiple sources. The results are important and indirectly provide further evidence of the presence of microplastics, which can be ingested by biota, in the marine environment.
    83. 83
      Bråte, I. L. N.; Eidsvoll, D. P.; Steindal, C. C.; Thomas, K. V. Plastic ingestion by Atlantic cod (Gadus morhua) from the Norwegian coast. Mar. Pollut. Bull. 2016, 112 (1), 105– 110,  DOI: 10.1016/j.marpolbul.2016.08.034
      There is no corresponding record for this reference.
    84. 84
      Anastasopoulou, A.; Mytilineou, C.; Smith, C. J.; Papadopoulou, K. N. Plastic debris ingested by deep-water fish of the Ionian Sea (Eastern Mediterranean). Deep Sea Res., Part I 2013, 74 (0), 11– 13,  DOI: 10.1016/j.dsr.2012.12.008
      There is no corresponding record for this reference.
    85. 85
      Jantz, L. A.; Morishige, C. L.; Bruland, G. L.; Lepczyk, C. A. Ingestion of plastic marine debris by longnose lancetfish (Alepisaurus ferox) in the North Pacific Ocean. Mar. Pollut. Bull. 2013, 69 (1), 97– 104,  DOI: 10.1016/j.marpolbul.2013.01.019
      There is no corresponding record for this reference.
    86. 86
      Vendel, A. L.; Bessa, F.; Alves, V. E. N.; Amorim, A. L. A.; Patrício, J.; Palma, A. R. T. Widespread microplastic ingestion by fish assemblages in tropical estuaries subjected to anthropogenic pressures. Mar. Pollut. Bull. 2017, 117 (1), 448– 455,  DOI: 10.1016/j.marpolbul.2017.01.081
      There is no corresponding record for this reference.
    87. 87
      Wójcik-Fudalewska, D.; Normant-Saremba, M.; Anastácio, P. Occurrence of plastic debris in the stomach of the invasive crab Eriocheir sinensis. Mar. Pollut. Bull. 2016, 113 (1), 306– 311,  DOI: 10.1016/j.marpolbul.2016.09.059
      There is no corresponding record for this reference.
    88. 88
      Miranda, D. d. A.; de Carvalho-Souza, G. F. Are we eating plastic-ingesting fish?. Mar. Pollut. Bull. 2016, 103 (1), 109– 114,  DOI: 10.1016/j.marpolbul.2015.12.035
      There is no corresponding record for this reference.

  • Supporting Information

    Supporting Information

    The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.est.8b01611.

    • Explanation and definition of scores and scoring of individual papers (PDF)


    Terms & Conditions

    Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.