Sources of Surface Water PFAS Contamination
PFAS reach freshwater systems through multiple pathways. Industrial and municipal wastewater discharges — even after conventional treatment — introduce PFAS from manufacturing, commercial, and domestic sources. Stormwater runoff carries PFAS from treated surfaces, roads, and urban environments. Atmospheric deposition of PFAS transported globally through the atmosphere falls as rain and dry deposition onto watersheds.
AFFF contamination from airports, military bases, and industrial fire training areas is among the most concentrated sources, creating point-source contamination in receiving streams and lakes. Landfill leachate — from facilities that accepted PFAS-containing products and materials — is a significant but often underappreciated source of freshwater PFAS contamination.
PFAS Levels in U.S. and Global Waters
The USGS National Water Quality Assessment has documented PFAS in surface water across the United States, with detection rates exceeding 70% in urbanized watersheds and near industrial and military sources. Great Lakes waters contain measurable PFAS, with Lake Michigan showing some of the highest freshwater PFAS concentrations in the Great Lakes system due to proximity to Chicago-area industrial and municipal discharges.
Internationally, heavily industrialized rivers in China (Pearl River Delta, Taihu Lake basin), European rivers downstream of PFAS manufacturing facilities (Po River in Italy, Rhine in Germany and Netherlands), and rivers near AFFF-using airports globally show elevated PFAS concentrations. Some Arctic freshwaters receive PFAS through long-range atmospheric transport, demonstrating truly global contamination.
Recreational and Fishing Exposure
Swimming, kayaking, and other water contact recreational activities in PFAS-contaminated water contribute to dermal PFAS absorption, particularly for short-chain compounds with greater skin penetration. Children playing in contaminated water — especially in splash pads and swimming areas with high contact time — receive higher per-body-weight exposure than adults.
Sport fishing in contaminated water creates exposure through fish consumption. Many states have issued fish consumption advisories for PFAS-contaminated lakes and rivers, recommending limits on frequency and quantity of consumption, particularly for larger, older fish that bioaccumulate higher PFAS levels. Anglers should check state fish advisory websites before consuming recreationally caught fish from areas with potential PFAS contamination.