This SERDP and ESTCP webinar focuses on DoD-funded research to improve understanding of the ecological risks of per- and polyfluoroalkyl substances (PFAS). Specifically, investigators will discuss the pathways and rates of PFAS uptake, bioaccumulation, and biomagnification within freshwater food webs, and a tiered approach for assessing PFAS risk to threatened and endangered species.

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Webinar #131 (04/08/2021)

Advances in Understanding PFAS Ecological Risks

Dr. Marie Kurz, The Academy of Natural Sciences of Drexel University

Dr. Jamie Suski, EA Engineering, Science, and Technology, Inc.

April 8, 2021

12:00 PM ET (9:00 AM PT)

Presentation Slides

Abstracts

"Uptake, Bioaccumulation and Biomagnification of PFAS by Freshwater Food Webs" by Dr. Marie Kurz ( SERDP Project ER19-1032 Webpage)

The manufacture, use, and disposal of PFAS-containing products has resulted in significant environmental PFAS contamination, impacting hundreds of Department of Defense (DoD) sites with historical use of aqueous film forming foam (AFFF). PFAS are transported into aquatic environments via stormwater runoff and contaminated groundwater plumes. Because of their mobility and persistence in aquatic systems, it is critical to understand the ecological and human health risks associated with the presence of PFAS in aquatic habitats. There is growing evidence that some PFAS bioaccumulate. However, the extent and mechanisms of bioaccumulation and biomagnification of PFAS in food webs, as well as their bioavailability, are not well characterized nor understood. This presentation will provide an overview of PFAS dynamics in aquatic ecosystems and an introduction to our ongoing project combining field observations and laboratory experiments to investigate the pathways and rates of PFAS uptake, bioaccumulation, and biomagnification within freshwater food webs affected by AFFF-use.

“Investigating Potential Risk to Threatened and Endangered Species from PFAS on Department of Defense Sites” by Dr. Jamie Suski ( SERDP Project ER18-1626 Webpage)

This presentation will cover the development of an approach for identifying species-specific exposure potential to PFAS using spatial analysis. Exposure potential analysis provides a map that illustrates the overlap of critical habitat with areas of suspected PFAS contamination. Through use of this technology, protected species (or taxa) are ranked by those that occupy or feed in the greatest proportion of PFAS impacted habitat. Species can then be prioritized for hazard and/or risk assessments. In this project, we carried two species (northern pine snake and bald eagle) through to develop a probabilistic risk framework on site specific perfluorooctane sulfonate (PFOS) concentrations. These species were identified as having high exposure potential from the spatial model. There is currently no risk assessment available for PFAS exposure to reptiles and the protected bald eagles that occupy many DoD installations and have dietary preferences for fish which are known to accumulate PFAS. This research benefits the DoD by applying a rapid screening-level approach to determine wildlife receptors that may be at greatest risk of exposure. Furthermore, the probabilistic risk framework developed for reptiles and avian predators illustrates an initial path forward in conducting full ecological risk assessments on DoD sites.

Speaker Biographies

Dr. Marie Kurz is a senior scientist at The Academy of Natural Sciences of Drexel University in Philadelphia, Pennsylvania. Dr. Kurz’s research addresses the transport and transformation of chemical constituents in freshwater systems, focusing on the ecological processes and human activities these dynamics reflect. She currently leads a SERDP-funded project investigating the extent, pathways, and rates by which PFAS are taken up by and transferred through stream food webs. In addition to research, a large component of Dr. Kurz’s work involves synthesizing her own and other research findings into diagnostic tools and guidance to support effective management and restoration of stream water quality and ecosystem integrity. She earned her bachelor’s degree in geology from The College of William and Mary in Virginia and her doctoral degree in geology from the University of Florida.

Dr. Jamie Suski is a senior scientist at EA Engineering, Science and Technology, Inc., PBC in Hunt Valley, Maryland. Dr. Suski’s current area of research focuses on ecotoxicological effects and risk assessment of contaminants of emerging concern, including PFAS. Since 2018, she has served as the principal investigator or co-principal investigator on several research grants for novel approaches to assess PFAS risk to threatened and endangered species and investigate abiotic and biotic influences on bioconcentration of PFAS in freshwater fish. She is also currently leading research efforts on the ecotoxicity and biodegradation of fluorine-free replacement firefighting foams. Dr. Suski is a co-author on the ecotoxicology section of the technological regulatory document for the PFAS team at the Interstate Technical Regulatory Council (ITRC). She earned a bachelor's degree in biology at Towson University in Marlyand, a master’s degree in environmental toxicology from the University of Maryland, and a doctoral degree in ecology from Texas Tech University.