In April 2026, the Texas Attorney General issued a Civil Investigative Demand to Lululemon, one of the most recognizable activewear brands in the world, over the potential presence of PFAS in products marketed to health-conscious consumers. Lululemon confirmed it had used PFAS in its durable water repellent products before phasing them out in early 2024. A class action lawsuit in California had already been filed making parallel allegations.
For anyone who has worn activewear without thinking about what chemical treatments were applied to the fabric, this is the story that reframes the question.
What PFAS Are
Per- and polyfluoroalkyl substances are a class of over 12,000 synthetic chemicals characterized by carbon-fluorine bonds, among the strongest in organic chemistry. That bond strength is what makes them useful as repellents and what makes them persistent: they do not break down in the environment or in the human body. Hence the name forever chemicals.
PFAS are used across a wide range of industrial and consumer applications: nonstick cookware, food packaging, firefighting foam, stain-resistant carpeting, and water-repellent clothing treatments. In the activewear industry, they appear primarily in durable water repellent (DWR) coatings, stain resistance finishes, and some odor-control treatments applied to synthetic fabrics.
How PFAS End Up in Workout Clothes
PFAS are not in the base fiber of most activewear. They are applied as surface treatments after the fabric is woven or knitted. A polyester or nylon fabric treated with a PFAS-based DWR coating will bead water, resist staining, and maintain its appearance after repeated washing. These are commercially valuable properties in performance activewear, which is why the category adopted them as standard practice.
The problem is that these treatments are not disclosed on the fiber content label. A garment listed as 87% polyester, 13% spandex tells you nothing about whether a PFAS-based coating was applied before it left the factory. Until independent testing, a brand's restricted substances list, or an enforcement action brings the information forward, the consumer has no way to know.
This is precisely the situation the Lululemon investigation addressed. The Texas AG's office examined whether consumers who bought products marketed as wellness-focused had been misled about the presence of chemicals they would not reasonably expect given the brand's positioning.
What the Health Research Shows
The EPA has linked PFAS exposure to thyroid hormone disruption, immune system suppression, elevated cholesterol, pregnancy-induced hypertension, reduced fertility, and increased risk of certain cancers including kidney and testicular cancer, based on human epidemiological studies. PFAS compounds have been detected in the blood of virtually all Americans according to CDC biomonitoring data, reflecting decades of widespread exposure from multiple sources.
For activewear specifically, the exposure concern is not just incidental contact. Exercise creates conditions that maximize dermal absorption: elevated skin temperature, open pores, and sweat that accumulates at the fabric-skin interface rather than being absorbed by hydrophobic synthetic fibers. A 2021 analysis in Sustainability examining transdermal chemical absorption from synthetic textiles found that exercise conditions are more favorable for dermal uptake than resting conditions. PFAS-treated activewear worn during exercise is a direct skin exposure pathway operating under conditions that favor absorption.
Short-Chain PFAS: The Replacement Problem
Many brands have moved away from long-chain PFAS, specifically perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), which have been the most studied and are subject to the most regulatory restriction. The replacements, shorter-chain PFAS compounds and related fluorochemistry, are increasingly being identified as carrying similar persistence and toxicity profiles.
A brand that claims to be PFAS-free may be free of the specific long-chain compounds that have been restricted while still using shorter-chain replacements that are not yet subject to the same regulatory scrutiny. Independent verification through OEKO-TEX Standard 100 testing, which covers specific PFAS compounds in the restricted substances list, is the meaningful signal rather than a brand claim alone.
What Lower-PFAS Activewear Looks Like
Avoiding PFAS in activewear starts with the base fiber and the finishing chemistry. A cellulosic fiber like TENCEL Lyocell does not require a DWR coating to perform its core moisture management function. Its moisture regulation is structural: the fiber absorbs sweat into its core rather than repelling it at the surface, which means the performance case for a water-repellent coating simply does not apply in the same way.
Kaplan et al. (2014), in Fibers and Polymers, documented TENCEL's moisture management and thermal comfort advantages in active wear settings. The Sempre Leggings are 92% TENCEL Lyocell, certified to OEKO-TEX Standard 100, which independently tests for PFAS compounds among over 100 restricted substances. That certification is the verifiable standard. The Lululemon case is the illustration of why the verifiable standard matters more than the brand claim.
The Practical Takeaway
PFAS in activewear is not a theoretical concern. It was standard industry practice at the most prominent brand in the category through at least early 2024, and it remains likely present in products currently in circulation from multiple brands that have not yet faced the scrutiny Lululemon has. The fiber content label does not disclose it. Independent certification does.
When you are choosing activewear, the question is not just what the fabric is made of. It is what was done to the fabric before you bought it, and whether anyone independent has verified the answer.
Sources
Texas Attorney General. (2026, April 13). Attorney General Ken Paxton Launches Investigation into Lululemon Over Potential Presence of Toxic "Forever Chemicals" in Activewear. texasattorneygeneral.gov.
U.S. Environmental Protection Agency. (2024). Our Current Understanding of the Human Health and Environmental Risks of PFAS. EPA.gov.
Kaplan, S., et al. (2014). Thermal comfort of lyocell and other fibers in active wear. Fibers and Polymers, 15(6).
OEKO-TEX Association. (2024). OEKO-TEX Standard 100 Testing Criteria. oeko-tex.com.
