WASHINGTON — Wastewater studies across the United States and globally have detected widespread presence of per- and polyfluoroalkyl substances (PFAS), known as "forever chemicals," highlighting ongoing challenges for water treatment and public health.
Researchers and environmental groups documented elevated PFAS levels in influent, effluent and biosolids from wastewater treatment plants, with contamination appearing in nearly all sampled waterways in some assessments. A Waterkeeper Alliance analysis released in 2025 found PFAS at 98 percent of tested sites across 19 states, with concentrations often higher downstream from treatment facilities and biosolids application areas.
PFAS, used in products ranging from nonstick cookware and firefighting foams to consumer goods, resist natural breakdown and accumulate in the environment and human bodies. Wastewater treatment plants serve as a key conduit, receiving the chemicals from household, industrial and commercial sources before discharging treated water into rivers, lakes and groundwater.
A multi-university study published in the Proceedings of the National Academy of Sciences in early 2025 revealed that organofluorine compounds, including those from pharmaceuticals, comprise a substantial portion of fluorine in municipal wastewater, with implications for downstream drinking water supplies serving millions of people.
Global monitoring shows regional variations. U.S. sewage sludge has recorded some of the highest concentrations, with totals reaching thousands of nanograms per gram in dry weight in certain samples, while Nordic countries report lower levels due to earlier regulatory actions. Short-chain PFAS and precursors have increased in many locations as industries shift from legacy compounds like PFOA and PFOS.
The U.S. Environmental Protection Agency has taken steps to address the issue. In July 2026, the agency released draft guidance for reducing risks from PFOA and PFOS in biosolids applied to land. It has also supported expanded testing methods for PFAS in wastewater and other media.
Several states have moved ahead with their own measures. At least 13 states considered policies in 2026 targeting PFAS in sludge used as fertilizer, including testing requirements and restrictions on land application. North Carolina released preliminary study data in January 2026 confirming PFAS in wastewater and biosolids.
Health officials link certain PFAS to potential risks including immune system effects, developmental issues and cancer, though exposure sources are multiple. The chemicals enter water systems through industrial discharges, consumer waste and legacy contamination.
Treatment remains difficult. Conventional wastewater processes remove only a portion of PFAS, sometimes transforming precursors into more mobile forms that pass through into effluent. Advanced methods such as activated carbon adsorption, membrane filtration and thermal destruction show promise but face cost and scalability hurdles.
Officials continue monitoring and research. The EPA and state agencies are expanding data collection on biosolids and treatment plant performance, while international efforts seek better understanding of global cycling through water systems.
No immediate nationwide federal limits apply specifically to PFAS in wastewater discharges, leaving much of the response to states and utilities. Further studies and regulatory developments are expected as detection capabilities improve and contamination patterns become clearer.
