Experts say no human problem with pharmaceuticals in drinking water
Leading researchers reassure drinking-water managers that the threat to human health has been overblown.
After the 2002 publication in ES&T of monitoring data showing a wealth of pharmaceuticals and personal care products (PhPCPs) in U.S. streams, researchers scrambled to understand the significance of the findings. Meanwhile, citizens groups have raised concerns over human health dangers posed by PhPCPs in drinking water. This concern has been overblown, scientists involved with the research told attendees at the American Water Works Association’s (AWWA) annual convention in June.
“A lot of people . . . over-interpreted some of our findings, especially with personal care products, to say that a certain compound was commonly found. The truth is that most of the compounds were not commonly detected,” U.S. Geological Survey hydrologist Michael Focazio told convention attendees.
The 2002 study looked for 95 contaminants from industrial, human, and agricultural wastewater sources in 139 U.S. streams and found very low levels of many of the compounds (Environ. Sci Technol. 2002, 36, 1202–1211).
Loads of occurrence data have since been generated about PhPCPs in streams that show only very low levels, the panel of scientists said. Yet, many of AWWA’s members, who work in public and private water utilities, are still concerned about potential human health effects, comments Al Roberson, AWWA security and regulatory affairs director. He adds, “They are all asking, ‘What is the relevance to human health of these low levels?’”
“We are talking about thousands of different compounds in the source water, and yet there are a lot of public health mysteries,” pointed out Bill Robinson, who attended the AWWA convention and is director of the Upper San Gabriel Valley Municipal Water District. “Who knows when a contaminant that is considered safe now will finally be found to be harmful to humans?”
Research detailing the feminization of fish from low levels of exposure to endocrine disrupters has scared the public into thinking that drinking water is contaminated, several of the scientists said. Shane Snyder is an environmental toxicologist with the Southern Nevada Water Authority and has studied treatment methods to remove PhPCPS from drinking water. He said that research on endocrine disrupters and pharmaceuticals has been “crossed up way too much” in the public’s mind. “The idea of feminization of fish is pretty dramatic for anyone to consider. But again it all has to be looked into in context.”
Frans Schulting of the Global Water Research Coalition, an international, nonprofit water research alliance formed in 2002, agreed. The presence of PhPCPs in drinking water “is not an issue about public health,” he said. European scientists have been studying these chemicals longer than their U.S. counterparts, and the science strongly supports that conclusion.
However, the researchers cautioned that in certain places contaminant concentrations are high enough to warrant further public-health studies. These include areas downstream from large animal farms and spots where human waste has been directly discharged because of a septic system overflow or a lack of a wastewater treatment plant. Certain pharmaceuticals, especially those that are highly toxic at low levels and steroid hormones, should be looked at more closely than chemicals such as caffeine, the researchers added.
“Aquatic exposure is really the concern,” said Christian Daughton of the U.S. EPA’s National Exposure Research Laboratory. Researchers still don’t fully understand what feminization and masculinization of fish means for the overall health of fish populations.
“The key is to be able to do the experiment at the bench scale and under more natural field conditions,” adds David Graham at the University of Kansas. “But there isn’t a lot of political will to do these types of studies in the U.S., especially. They are doing it in Europe, but like everywhere else, the money is not growing on trees.”
