Abstracts

“Factors Influencing PFAS Bioaccumulation and Biomagnification in Marine Food Webs Associated with AFFF Sources in a New England Estuary” by Dr. Celia Chen (ER22-3349) 

The goal of this multi-year study is to investigate the pattern and profiles of PFAS bioaccumulated in lower trophic level marine organisms and transferred to higher trophic levels in marine food webs and to determine toxicity of less-studied PFAS compounds. The approach has utilized field studies in and around Great Bay estuary. The project involves conducting field studies to determine PFAS concentrations in sediments and water and in lower trophic level organisms; conducting laboratory studies using the model organisms, Leptocheirus plumulosus (amphipod) and Fundulus heteroclitus (forage fish), to measure bioaccumulation of PFAS within each species from contaminated sediments across different organic matter treatments; and conducting toxicity studies for legacy and emerging PFAS using three marine taxa: the marine flagellate Tisochrysis lutea, the zooplankton species Acartia tonsa, and L. plumulosus. The presentation will discuss studies conducted to date and anticipated next steps.

“Bioavailability, Bioaccumulation, and Toxicity of PFAS in Benthic Biota Exposed to Impacted Marine 
Sediments” by Dr. Carrie McDonough (ER22-4003)

This project aims to fill knowledge gaps related to the bioavailability and environmental impacts of PFAS in marine sediments impacted by AFFF. Sediments are a significant reservoir for PFAS contamination. However, progress in understanding the relevance of these sediment-associated PFAS for biota has been slowed due to the complexity of PFAS-sediment interactions. Objectives of this project include directly monitoring bioavailable PFAS in sediment-seawater systems representative of AFFF-contaminated environments and comparing bioavailability measurements to PFAS uptake in key benthic prey species with distinct physiologies and association with the sediment, including polychaetes and shellfish. This presentation will describe progress to date evaluating the use of rapidly equilibrating passive porewater samplers that selectively measure bioavailable PFAS in laboratory-controlled sediment-water systems containing synthetic or natural PFAS-fortified sediments, as well as progress measuring uptake and accumulation of various perfluoroalkyl acids (PFAAs) in benthic polychaetes. 

“The Relative Toxicities of Current Use AFFF and Next Generation Alternatives to Aquatic Species for Informing Risk Assessment” by Dr. Jason Hoverman (ER20-1537)

This project supports SERDP’s efforts in environmental management of PFAS with an emphasis on the ecological effects of PFAS and their replacements. With the urgent need to find replacements for firefighting foams containing PFAS, scientists have developed a broad diversity of new technologies. However, before the selection and implementation of PFAS-free alternatives in fire-suppression operations, research must address their potential environmental impacts. This presentation discusses research examining the acute and chronic toxicity of PFAS-free alternatives using aquatic systems as a model. The core outcome of these studies will be an improved understanding of the relative toxicity of PFAS-free alternatives compared to short-chain AFFF formulations currently in use by the DoD. Ultimately, these efforts will enable DoD to proceed with sound ecological risk 
assessments involving the development of fluorine-free surfactants that will meet the DoD performance requirements.

Speaker Biographies

Dr. Celia Chen is a research professor in the Department of Biological Sciences at Dartmouth College where she works on contaminant bioaccumulation and fate in aquatic food webs. She and her collaborators have been investigating the fate of PFAS in marine, estuarine, and freshwater food webs. Dr. Chen’s past research has also focused on toxic metals and mercury in aquatic ecosystems, including lakes and ponds, reservoirs, streams and rivers, and estuaries. She also communicates and facilitates the application of the research findings to policy makers, stakeholder groups, and the public at the state, national, and international levels. Dr. Chen received a bachelor’s degree from Dartmouth College, a master’s degree from the University of Rhode Island, and a doctoral degree from Dartmouth College. 

Dr. Carrie McDonough is an assistant professor in the Department of Chemistry at Carnegie Mellon University. Since 2017, she has been involved in research on the bioaccumulation and biological transformation of known and novel PFAS using in vitro and in vivo experimental techniques combined with high-resolution mass spectrometry. McDonough’s research team is currently investigating the bioavailability and bioaccumulation of PFAS associated with AFFF in marine benthic biota that are key prey items. They are also evaluating passive sampling materials to select for the bioavailable PFAS fraction in these complex environments with the ultimate aim of facilitating environmental risk assessment and advancing our understanding of PFAS uptake and trophic transfer in marine food webs. Dr. McDonough received a bachelor’s degree in chemistry from the Massachusetts Institute of Technology and a doctoral degree in oceanography at the University of Rhode Island Graduate School of Oceanography.

Dr. Jason Hoverman is a professor in the Department of Forestry and Natural Resources at Purdue University. He has served a principal and co-principal investigator on projects funded by SERDP, the Environmental Protection Agency, the United States Geological Survey, the National Science Foundation, and the National Institutes of Health to conduct research in the fields of ecotoxicology, disease ecology, and community ecology. Since 2016, Dr. Hoverman has worked extensively to understand the effects of PFAS on freshwater aquatic communities. This work has included studies to assess bioaccumulation and depuration rates across different exposure routes, adverse effects on the growth and development, interactive effects with pathogens, and toxic synergies associated with PFAS mixtures. He has authored over 100 peer-reviewed papers and 3 book chapters and has delivered over 100 presentations and posters. Dr. Hoverman received bachelor’s and doctoral degrees in ecology and evolution from the University of Pittsburgh.