Assessing the Toxicity of PFAS Chemicals to Aquatic Organisms Webinar
About the Webinar

Watch the webinar (February 23, 2022)
Among the many questions surrounding per- or polyfluoroalkyl substances (PFAS) are their potential effects on aquatic communities. While much of the initial research effort has focused on ecological effects of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), there is a much wider range of PFAS that can occur in the environment―both as a result of more recently developed compounds and the breakdown products of other PFAS. Effective management of PFAS in aquatic systems requires understanding of the potential effects of a more complete range of PFAS chemicals.
EPA is working to explore the relationships between PFAS toxicity and chemical structure for several aquatic species to help identify and predict the toxicity of PFAS and PFAS mixtures of greatest ecological concern in support of the development of water quality guidelines. This involves measuring the toxicity of PFAS with varying structural features, determining variation in sensitivity across species, and grouping PFAS chemicals by their inferred toxic modes of action (MoA). This webinar will discuss initial findings that sublethal toxicity is strongly related to fluorinated chain length as well as the structure of the non-fluorinated “head” group, and that differences in toxicity of certain PFAS across structures suggest that multiple PFAS MoAs likely exist.
About the Presenters
David Mount, Ph.D.
Dave is an aquatic biologist in EPA’s Office of Research and Development, where he has worked since 1995. Prior to joining EPA, Dave worked for 5 years in the private sector and 2 years conducting research for the Department of the Interior. Dave’s research has covered a variety of topics in environmental toxicology, including the bioavailability of environmental contaminants, methods to test and evaluate sediment contamination, assessing and modeling effects of chemical mixtures, and the effects of dietary exposure to contaminants. Dave holds a Ph.D. from the University of Wyoming.
Sarah Kadlec, Ph.D.
Sarah is a biologist in EPA’s Office of Research and Development, Great Lakes Toxicology and Ecology Division in Duluth, MN. She received her Ph.D. from the University of Minnesota in 2017, where she studied the relationships between estrogenic exposure and developmental abnormalities in smallmouth bass. Her current research focuses on the effects of emerging and legacy contaminants on freshwater organisms in support of ecological risk assessment.