Wildfire ash can contain toxic mix
The U.S. Geological Survey finds that soil runoff from residential wildfires can harm aquatic species
A new U.S. Geological Survey (USGS) study of ash and soil samples from the wildfires in Southern California last November suggests that metals in the ash may create health and environmental problems. Ash samples from 2 residential areas and 26 other sites within the burned areas contained caustic alkali materials and may have elevated levels of metals, such as arsenic, lead, zinc, and copper.
The study also shows that rainwater runoff from burned areas may adversely affect ecosystems and surface drinking-water supplies. Habitats critical for some aquatic species may be affected by spikes in alkalinity as rainwater mixes with ash to form surface runoff, the researchers note. The research was conducted as part of the USGS Southern California Multi-Hazards Demonstration Project.
