Does your water filter remove PFAS forever chemicals?

What's in unfiltered water

PFAS (forever chemicals) enter drinking water from firefighting foam sites, manufacturing plants, and contaminated soil. A 2026 investigation in McKeesport, Pennsylvania documented what happened when firefighting foam accidentally leaked into the public water system. Researchers found multiple types of PFAS in tap water samples from residents' homes.

The contamination event revealed a critical gap: the city's standard water treatment didn't fully remove the chemicals. Residents were drinking PFAS-contaminated water without knowing it.

What the research says

The McKeesport study measured specific PFAS compounds in tap water before and after the contamination was identified. The findings showed that conventional water treatment processes remove some but not all PFAS. Shorter-chain PFAS molecules, which are increasingly common as manufacturers switch away from older formulations, are the hardest to filter out.

Standard activated carbon filters (like Brita pitchers) catch some larger PFAS molecules but let smaller ones through. Reverse osmosis systems are the most effective home option, removing 90%+ of PFAS. Under-sink reverse osmosis units outperform pitcher-style filters by a wide margin.

No home filter removes 100% of PFAS. But the right system can reduce exposure from tap water by an order of magnitude.

How to protect yourself

Check if your water utility has been tested for PFAS through the EPA's UCMR 5 program. If PFAS are detected, install a reverse osmosis or NSF-certified PFAS filter. Pitcher filters are better than nothing but won't catch everything. Test your water independently if you live near a military base, airport, or industrial site.