PFAS ('Forever Chemicals')
Also known as: Forever chemicals, PFOA, PFOS, GenX, Per- and polyfluoroalkyl substances
Newly regulated 'forever chemicals' — a fast-emerging issue as EPA's first-ever PFAS limits take effect and monitoring expands nationwide.
PFOA & PFOS 4.0 ppt (ng/L). EPA finalized the first PFAS drinking-water standards in April 2024 (PFOA and PFOS at 4 parts per trillion, with limits for PFHxS, PFNA, HFPO-DA/GenX). Compliance monitoring and enforcement phase in over the following years, so reported MCL violations are still ramping up.
Linked to certain cancers (kidney, testicular), immune-system suppression, thyroid disruption, high cholesterol, and developmental effects. PFAS persist in the body and the environment for years — hence 'forever chemicals.'
Industrial discharges, firefighting foam (especially near airports and military bases), landfills, and consumer products. Highly mobile and persistent in groundwater.
Granular activated carbon, reverse osmosis, and ion-exchange resins remove PFAS. Look for filters certified to NSF/ANSI 53 or 58 for PFOA/PFOS.
PFAS are a family of thousands of synthetic 'forever chemicals' used since the 1950s in nonstick, waterproof, and stain-resistant products and firefighting foam. They don't break down, accumulate in the body, and have been detected in drinking water across the country.
In April 2024 the EPA set the first enforceable national PFAS drinking-water limits — 4 parts per trillion for PFOA and PFOS, among the lowest limits for any regulated contaminant. Because compliance monitoring and enforcement are still phasing in, formal MCL violations are only beginning to appear in federal data even though detections are widespread.
Expect PFAS to become one of the defining drinking-water stories of the decade as testing expands and thousands of systems install treatment to meet the new limits.
Common questions
What is the EPA limit for pfas in drinking water?
PFOA & PFOS 4.0 ppt (ng/L). EPA finalized the first PFAS drinking-water standards in April 2024 (PFOA and PFOS at 4 parts per trillion, with limits for PFHxS, PFNA, HFPO-DA/GenX). Compliance monitoring and enforcement phase in over the following years, so reported MCL violations are still ramping up.
Is pfas in drinking water dangerous?
Linked to certain cancers (kidney, testicular), immune-system suppression, thyroid disruption, high cholesterol, and developmental effects. PFAS persist in the body and the environment for years — hence 'forever chemicals.'
Where does pfas in water come from?
Industrial discharges, firefighting foam (especially near airports and military bases), landfills, and consumer products. Highly mobile and persistent in groundwater.
How do I remove pfas from my water?
Granular activated carbon, reverse osmosis, and ion-exchange resins remove PFAS. Look for filters certified to NSF/ANSI 53 or 58 for PFOA/PFOS.