Background: Data on PFAS contamination and uptake in freshwater benthic biota, particularly near sites with known groundwater contamination, are scarce. This project investigates PFAS contamination in the Little Neshaminy Creek watershed, Pennsylvania, which is adjacent to two former military bases with known groundwater PFAS contamination and exposure.

Objective(s): This study aims to evaluate the potential of using the invasive Asian Clam, Corbicula fluminea, to detect elevated PFAS contamination in surface water and sediment impacted by aqueous film-forming foams, and determine empirical partition coefficients for water, sediment, and tissue to better understand the fate and transport of PFAS in freshwater ecosystems.

Methods: PFAS concentrations were analyzed in surface water, sediment, and invasive Asian clam tissue, considering their potential as biomonitors at Penn State University.

Results: ΣPFAS19 ranged from 40 to 248 ng/L in surface water, ΣPFAS8 from 491 to 1081 ng/kg in sediment, and ΣPFAS5 from 428 to 2796 ng/kg in clam tissue. Perfluorooctane sulfonic acid (PFOS) predominated in all matrices. Partition coefficients revealed significant bioaccumulation potential, especially for PFOS. Linear correlations between tissue and environmental sediment (R² = 0.56) and water (R² = 0.86) PFOS concentrations suggest clam tissue as a biological indicator of PFOS contamination.

Conclusion: This study provides valuable insights into the distribution, fate, and potential impacts of the release of PFAS compounds in freshwater ecosystems. The presence of various PFAS compounds, including long-chain forms such as PFOA and PFOS, highlights the persistence and widespread distribution of these contaminants in the environment despite ongoing remediation.