If you have ever bought a jacket labeled “water-repellent” or leggings that promise to stay stain-free, there is a good chance you have worn PFAS in clothing without ever knowing it. These so-called “forever chemicals” have quietly shaped performance fabrics for decades, and in 2025 they became one of the most tightly regulated ingredient categories in the apparel industry. Here is a calm, practical look at what PFAS are, why they keep coming up in conversations about activewear, and how to make better choices without overhauling your closet overnight.
What is PFAS in clothing, exactly?
PFAS stands for per- and polyfluoroalkyl substances—a family of thousands of synthetic chemicals valued for one stubborn talent: repelling water, oil, and stains. They earned the nickname “forever chemicals” because the carbon-fluorine bond at their core resists breaking down, so they can linger in the environment—and in our bodies—for years. In textiles, PFAS are the invisible finish behind a lot of familiar marketing language: water-resistant, stain-repellent, wrinkle-free, and some performance “technical” coatings.
Why activewear keeps coming up
Performance clothing is built around the exact properties PFAS deliver, which is why outdoor gear, rain shells, and some athletic apparel have leaned on these treatments for years. According to environmental researchers at the Minderoo Foundation, the same finishes that shrug off a coffee spill or a downpour are the ones most likely to involve fluorinated chemistry. That does not mean every pair of leggings is coated—most basic, untreated fabrics are not—but it does explain why activewear sits near the center of the discussion.
What does the science say about the health risks?
This is where it pays to be measured. The U.S. EPA notes that exposure to certain PFAS has been associated with a range of effects in research, including a reduced ability of the immune system to respond to vaccines, as well as links to thyroid and cholesterol changes, liver effects, and some cancers. Public health experts at Johns Hopkins emphasize that most everyday exposure comes through food and water rather than fabric, and that the science on skin absorption from clothing is still developing. Early 2025 research has begun examining whether sweat could increase how much transfers through skin—a useful reminder that the picture is not yet complete. The honest takeaway: PFAS are worth reducing where you reasonably can, not panicking over.
The 2025 bans changing what is on store shelves
Regulation has moved faster than the headlines. As of January 1, 2025, both California (AB 1817) and New York (S5648) prohibit the sale of apparel and textiles with intentionally added PFAS. California measures compliance by total organic fluorine, capped at 100 parts per million now and dropping to 50 ppm in 2027, with specialized outdoor gear for severe wet conditions phased in by 2028. Per a multistate policy tracker, more than a dozen states—including Maine, Minnesota, Colorado, Washington, Connecticut, and Maryland—have now passed PFAS restrictions across various product categories. The practical effect for shoppers: the apparel industry is being pushed toward PFAS-free finishes, and more brands are disclosing what they use.
How to spot—and avoid—PFAS in your wardrobe
You do not need a chemistry degree, just a few habits. Be a little skeptical of finishes you do not actually need: unless you are heading into a storm, “durable water repellent” treatment on everyday leggings or tees is doing more for marketing than for you. Natural and untreated fibers—and brands that explicitly state they are PFAS-free—are a safe default. When you do buy technical gear, look for labels and brand pages that name their chemistry rather than hiding behind vague “performance” claims. And resist the urge to throw out everything you own; the goal is smarter future choices, not waste.
Today's small choice: Next time a clothing label brags about being water- or stain-proof, pause and ask whether you really need that finish—and if not, reach for the simpler, untreated option instead.
Sources: U.S. EPA on PFAS health risks; Johns Hopkins Bloomberg School of Public Health; Morgan Lewis: NY & CA apparel bans; MultiState PFAS law tracker; Minderoo Foundation on PFAS in activewear.