Does wearing PFAS-treated outdoor clothing like waterproof jackets raise your PFAS levels?

What's actually in it

Waterproof and water-resistant outdoor clothing (hiking jackets, rain gear, ski wear, athletic gear) is typically treated with durable water repellent (DWR) coatings. The most effective DWR coatings are made with PFAS, specifically long-chain PFAS that create a tight water-repelling surface.

PFAS absorb through skin, especially under warm or sweaty conditions. They also shed from fabric into dust that can be inhaled or ingested. People who wear PFAS-treated outdoor clothing frequently, especially during exercise when they're sweating, have more skin contact time with these chemicals than someone who wears the garment occasionally.

What the research says

A 2026 study in Ann Occup Environ Med using data from the Korean National Environmental Health Survey found that people who frequently wore waterproof outdoor clothing had significantly higher serum PFAS concentrations than people who wore such clothing less often. The association was dose-dependent: more frequent use correlated with higher blood levels.

The study is notable because it's population-level data from a national survey, not a small case study. The signal was strong enough to show up across a diverse group of people with varying diets and other exposure sources.

Non-PFAS DWR alternatives exist: wax-based coatings, polyurethane membranes, and newer PFAS-free synthetic DWRs offer water resistance without these chemicals. For everyday rain gear and casual outdoor wear, these alternatives work well. For high-performance mountaineering gear requiring extreme water resistance, the tradeoffs are more complex, but the exposure difference is real.