Can waterproof outdoor jackets raise the PFAS levels in your blood?

What's actually in it

Waterproof jackets, hiking pants, and rain gear get their water-repelling power from coatings made with per- and polyfluoroalkyl substances (PFAS). These are the same forever chemicals found in nonstick pans and food packaging. The coating keeps rain out, but it doesn't stay locked in the fabric. PFAS can rub off onto your skin, release into the air around you, and eventually get into your bloodstream.

What the research says

A 2026 study in Ann Occup Environ Med looked at data from South Korea's national health survey and measured PFAS levels in the blood of people who wore outdoor clothing at different frequencies. The pattern was clear: people who wore outdoor jackets and gear more often had higher blood concentrations of PFOS, PFOA, PFHxS, and PFDA.

The link held up even after the researchers accounted for age, diet, smoking, and other sources of PFAS exposure. Outdoor clothing was an independent contributor to blood PFAS levels.

This matters because PFAS build up in your body over time. They've been linked to thyroid problems, immune suppression, and increased cholesterol. Every source you can cut out helps lower your total load.

If you need rain protection, look for jackets labeled PFAS-free or PFC-free. Several outdoor brands now use wax-based or silicone-based coatings instead. They don't last as long between treatments, but they won't leave forever chemicals in your blood.