Most leggings do not appear to contain PFAS, but a meaningful minority do. In 2022 testing published by Environmental Health News with the consumer blog Mamavation, an EPA-certified lab found fluorine, a screening indicator for PFAS, in 8 of 32 leggings and yoga pants, at levels from 10 to 284 parts per million. The other 75% tested clean. So the practical takeaway is not that all activewear is contaminated, but that you cannot tell by brand or price, and a few popular products did flag.
The lab measured total fluorine in the crotch area of each garment and treated anything above 10 ppm as a flag. An elevated fluorine reading is a strong hint that PFAS treatments, often used for stain, water, or odor resistance, or sweat-wicking, were applied. The eight flagged products, as Mamavation reported and EHN co-published, included items from Athleta Girl, Gaiam, Knix, Lululemon (the Align pant), LuLaRoe, Old Navy, Vuori, and Yogalicious. A separate round that also tested sports bras found fluorine in about two-thirds of the bras checked, in the nipple area.
A few caveats matter and are worth stating plainly:
Activewear is one of several wearables where these finishes show up. If you are mapping your exposure, the same question applies to smartwatch and fitness bands and to mattresses and bedding, both of which have their own test data.
The brands that tested non-detect for fluorine in this round were organic-fiber lines, including Groceries Apparel, Mate the Label, and Pact. That fits the pattern: plain cotton, wool, and other natural fibers without a performance finish are the least likely to carry a PFAS treatment. When you shop, the useful signals are:
Which leggings had PFAS? In the 2022 testing, flagged products came from Athleta Girl, Gaiam, Knix, Lululemon (Align), LuLaRoe, Old Navy, Vuori, and Yogalicious. Most other tested pants were clean.
Does Lululemon have PFAS? The Align pant flagged for fluorine in this round. A brand flagging on one product in one test is a reason to check for a current PFAS-free statement, not a permanent verdict.
How do I avoid PFAS in clothes? Favor plain organic cotton and wool, skip "stain-resistant" and "water-repellent" finishes unless the brand states they are PFAS-free, and look for OEKO-TEX or MADE SAFE certification.
Is fluorine the same as PFAS? Not exactly. Total fluorine is a screening test: a high reading strongly suggests PFAS were used, but it does not identify which compound or confirm the amount. It is the standard first-pass indicator that labs and advocates use before more expensive compound-specific testing.
Educational information, not medical advice. Know Your Exposure accepts no payment from any product brand; some links are affiliate links that never change what we recommend.