Jason Conder is a Senior Scientist with Geosyntec Consultants in Huntington Beach, CA. He has more than 15 years of experience in environmental toxicology, ecological and human health risk assessment, bioaccumulation and bioavailability of environmental contaminants, environmental chemistry, environmental monitoring technology, ecology, and statistics. He has provided technical expertise in ecological risk assessment and environmental toxicology to multinational clients addressing environmental liability and risk issues associated with contaminated sites. Jason has specific technical expertise associated with assisting several large, multi-stakeholder groups address the complex issues associated with contaminated sites in North America, Europe and Asia. In addition, Jason has been focusing on the environmental fate and bioaccumulation of emerging chemicals of concern such as Polyfluoroalkyl and Perfluoroalkyl Substances (e.g., PFOA and PFOS) since 2005. He has published more than 20 peer-reviewed articles in environmental toxicology and chemistry, presented technical work at numerous international scientific conferences, and has served on and co-chaired several technical workshops. Jason earned his Ph.D. in Environmental Science University of North Texas, a Master’s degree (Zoology) from Oklahoma State University (OSU) and a BS in Wildlife and Fisheries Ecology (OSU).
Prioritizing Data Needs For Assessing the Ecological Risks of PFASs in Habitats Impacted by Aqueous Film Forming Foam Releases
Perfluoroalkyl and Polyfluoroalkyl Substances (PFASs) have been widely used in numerous industrial and commercial applications since the 1950s, including aqueous film forming foams (AFFFs) used for fire suppression at airports, firefighting training facilities, and other industrial locations. PFASs such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are now routinely-detected in a wide variety of environmental media impacted by AFFF, and have prompted regulatory focus on exposures and risks. Many AFFF sites host ecological habitat or, due to the offsite transport potential for PFASs (especially for aquatic transport routes), may affect nearby or downgradient habitats. Unfortunately, there is little guidance on developing Conceptual Site Models (CSMs) and investigation plans to evaluate the ecological risks of PFASs at AFFF sites. This presentation will highlight key ecological risk considerations for PFAS at AFFF sites, based on reviews of PFAS fate and toxicology information, as well as ecological exposure modeling of PFAS exposures for wildlife at AFFF sites. Our work indicates that PFOS is likely to be a key PFAS of concern at many sites, particularly for avian wildlife. For example, PFOS comprised approximately 80% of the exposure of perfluoroalkyl acids to avian species at five AFFF sites, likely due to its prevalence in many historical AFFF formulations, ability to bioaccumulate in terrestrial and aquatic food webs, and partitioning to soils and sediments. However, exposures to other PFASs, especially perfluorohexane sulfonate (PFHxS) and perfluorodecane sulfonate (PFDS) may also be important, and suggest that avian toxicity testing should be prioritized for these particular PFASs. Model and review results also highlighted several practical steps for site-specific investigations for supporting ecological risk assessments, including:
- Focusing investigations on aquatic systems affected or downgradient of AFFF discharge areas;
- Screening measurements of PFASs in key abiotic environmental compartments (soils, sediments, and surface water);
- Measurements of PFAS in invertebrates and fish; and
- Measurements of organic carbon contents in soils and sediments to aid with modeling fate and availability.
Additional considerations for research needs and site-specific ecological risk management approaches will be presented, with the hopes of optimizing ecological risk-based decision making at AFFF sites.