PFAS and other toxic contaminants can enter surface water through overland flow, such as stormwater runoff, through industrial discharges, through atmospheric deposition and through discharge of contaminated groundwater.

Once in the surface water, contaminants can contribute toxicity to fish and other aquatic life. Some contaminants may also be taken up by local fish and other aquatic life in the process of bioaccumulation.

This not only increases the body burden of the chemicals in the fish themselves, potentially causing impacts, but it also creates an exposure pathway to higher life forms like birds who feed on fish (such as kingfishers, great blue heron, osprey, bald eagles), aquatic mammals like otters and humans through the consumption of contaminated fish.

Statewide Surface Water Study

DNREC’s Watershed Approach to Toxics Assessment and Restoration (WATAR) team conducted a comprehensive statewide PFAS surface water study in the fall of 2022 to document the nature, extent, magnitude and distribution of PFAS contamination in surface waters across the state. This initial survey contributes to Delaware’s understanding the overall distribution of PFAS in environmental media. The data may also provide important forensic clues, or lines of evidence, regarding the source(s) of PFAS in Delaware watersheds.

After reviewing the data collected during this study, DNREC determined that follow-up actions are required in several watersheds to examine anomalies or differences that were identified with regard to the magnitude of PFAS concentration(s), or with the distribution of family groups and subgroups.

DNREC recommends that the public be aware of PFAS concentrations in the waters that they frequent. While the science surrounding PFAS exposure is ever advancing, and as DNREC continues to learn and share information about PFAS in Delaware’s environment, understanding how one can limit exposure in their own lives is critical.

Related Topics:  EPA, GenX, HSCA, PFAS, PFOA, surface water, waste and hazardous substances, watar, water