Advancing the Understanding of the Ecological Risk of Per- and Polyfluoroalkyl Substances
Dr. Christopher Salice | Towson University
The overarching objectives of this project are twofold: (1) conduct ecotoxicity studies that yield defensible and usable Toxicity Reference Values (TRVs) for wildlife potentially exposed to common per- and polyfluoroalkyl substances (PFASs), including perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and other PFASs, and (2) develop and validate a low-cost, prioritization protocol for evaluating other PFASs that may drive risks at Department of Defense (DoD) sites. This improved understanding of the ecotoxicity of perfluorinated compounds and evaluation protocol can help guide site-specific risk assessment needs.
This project will conduct PFAS ecotoxicity studies on common (avian, fish, invertebrates) and historically underrepresented taxa (reptilian). Studies will be comprised of acute and chronic durations with endpoints designed to take advantage of Benchmark Dose methods for TRV derivation as well as traditional no observed adverse effect levels (NOAELs) and lowest observed adverse effect levels (LOAELs) for immediate application towards ecological risk assessments of PFASs. An additional emerging concern is that large “families” of PFASs with varying chain lengths are likely common at most PFAS contaminated sites although few have been evaluated for ecotoxicity. Exposure to these other PFASs may be likely, but no assessment of risk is possible because of a lack of toxicity data. This project will identify potential other PFASs with information and samples from active DoD installations and then develop a testing and prioritization protocol using aquatic invertebrates and fish. A prioritization algorithm will be used to combine different sources and types of information to yield a ranking of PFASs in terms of the likelihood of posing a risk to wildlife. This prioritization protocol can be applied to assess whether other, novel PFASs should undergo more extensive toxicity evaluation. This approach will be useful as new information emerges from site-specific risk assessment activities and will inform additional studies and data needs.
The lack of comprehensive, robust, and defensible ecotoxicity data on PFASs hinders risk assessment and represents a roadblock to sound environmental management decisions. The lack of a streamlined but robust approach for toxicity testing and decision-making regarding “other” PFASs that occur at high frequency and concentration at DoD sites will slow environmental management decisions and lead to unsupported risk decisions potentially resulting in unnecessary costs. This research to better understand the ecological risk of PFASs will help to ensure military readiness, range sustainability, and public health and environmental protectiveness. (Anticipated Project Completion - 2020)