EA Engineering, Science, Technology, Inc., PBC
Jamie Suski is an ecotoxicologist at EA Engineering, Science and Technology, Inc., PBC. She has a PhD from Texas Tech University and a Masters of Science degree from University of Maryland. Prior to joining EA, Dr. Suski worked for the U.S. Environmental Protection Agency and the U.S. Army.
FLASH POSTER PRESENTATION
Exploring Freshwater Species Sensitivity to Environmentally Persistent PFAS and PFAS Mixtures
Per- and Polyfluoroalkyl Substances (PFAS) are synthetic chemicals that are stable and persistent in the environment. PFASs were first discovered in 1938 by DuPont and trademarked as Teflon in the following years. In the 1960's the 3M company, in collaboration with the U.S. Navy developed the Aqueous Film Forming Foam (AFFF) to quickly and effectively extinguish fires. In 1999, EPA received information about the persistence, unexpected toxicity and bioaccumulation potential on PFOS. Subsequently, in 2000 3M announced it was discontinuing manufacturing perfluorooctanyl chemicals; despite the drastic domestic reduction of PFAS manufacturing, persistence of PFASs continues within all environmental compartments including, soil, water, air and in biota. Surface water near historically used fire training facilities and manufacturing plants have been reported to have PFAS contamination related to those activities. To date, most data available on the effects of PFAS to freshwater invertebrates were conducted as acute toxicity tests with the daphnid species, Daphnia magna exposed to Perfluoroalkyl sulfonic acid (PFOS) and Perfluoroalkyl carboxylic acid (PFOA). Out of thirty-six studies identified that tested PFAS on freshwater crustaceans, 24 used D. magna as the test species. Additionally, 19 of the 36 studies investigated the toxicity of PFOS and PFOA alone, 13 of which utilized D. magna as the test species. It should be noted however, that available studies indicate other crustacean species such as Moina macrocopa and Chyrodus sphaericus were the more sensitive to PFASs compared to D. magna. Additionally, within the dataset of sub-chronic exposures conducted with M. macricopa and D. magna, the species showed equal sensitivity to PFOS using a fecundity endpoint. Taken together, these data suggest D. magna may not be the optimal surrogate for freshwater crustacean sensitivity and future efforts will explore this hypothesis. Moreover, these studies investigated toxic effects of individual PFAS while PFAS in the environment is often present in mixtures, which may have interactions that elicit different physiological responses. Given the lack of available data on potentially more sensitive freshwater crustaceans and chronic exposures of environmentally persistent PFAS mixtures, which is the more likely exposure scenario, we have initiated zooplankton studies to explore and define the ecotoxicity of PFASs with limited data and as a mixture. These data are presented along with published studies to provide a species sensitivity distribution that may aid in more realistic management through risk assessment.