Athletic gear is everywhere, and “athleisure” is everyday clothing for many. Compared to what people exercised in decades ago, today’s workout gear seems vastly superior: Better fitting, wicking sweat, and much, much more comfortable. Cotton is a rarity, synthetics are king. And almost everything has materials that add stretch.
In recent years, concerns have emerged around the presence of endocrine-disrupting chemicals (EDCs) in everything from yoga pants to sports bras. These compounds, found in industrial and consumer products, have been linked to hormonal imbalances, fertility issues, and even cancer in animal studies. But does their presence translate into real-world risk? This is not an easy question to answer – but let’s look at some of the issues and the science.
What are EDCs?
Endocrine-disrupting chemicals are substances that can interfere with the endocrine (hormonal) system in animals and humans. EDCs can be natural or synthetic. They can mimic natural hormones, prevent hormones from binding to receptors in cells, and even affect the production of hormones in the body. Useful EDCs include prescription drugs like corticosteroids and birth-control pills. Common EDCs used for non medical-purposes include bisphenol A (BPA), phthalates, and per- and polyfluoroalkyl substances (PFAS). These EDCs are present in food packaging, plastics, cosmetics, water-repellent coatings, and other products. Most human exposure in the United States appears to come from food packaging. The FDA, which oversees food packaging, states that BPA is safe at the current levels detected in foods. Health Canada agrees, and states that skin contact from handling thermal printing paper may be a secondary but important route of exposure, highlighting concern about the dermal absorption potential of EDCs.
Athletic Gear and EDCs
Athletic wear is often made from synthetic materials such as polyester, nylon, and spandex. These fabrics may contain EDCs for various reasons:
BPA: Used in the production of certain plastics and resins, BPA has been detected in some sportswear. As noted above, BPA can be absorbed into the body through skin contact.
Phthalates: These chemicals are used to make plastics more flexible and are sometimes found in clothing materials.
Per- and polyfluoroalkyl substances (PFAS): Often referred to as “forever chemicals” due to their persistence in the environment, PFAS are used to make fabrics water- and stain-resistant.
Exposure Risks from EDCs in Clothing
It’s important to note that the identification of chemical does not automatically mean that its presence creates a risk. The potential for EDCs in a piece of clothing to affect health would depend on the type of EDCs, the concentration of EDCs in the clothing, the duration and frequency of wear, skin conditions or other factors (e.g., sweating?) that might affect absorption, and then, if absorbed, their ability to cause harm based on the amount absorbed. While studies have detected the presence of EDCs in athletic apparel, the actual risk to consumers is unclear and would be impossible to test prospectively. Perhaps not surprisingly and somewhat depressingly, given the ubiquity of EDCs in our modern environment, clothing appears to be one of the many sources of daily exposure. There are likely greater concerns about EDCs in cosmetics and food products, where exposure and absorption is more more likely. Even if we are not exposed through dermal contact by wearing them, discarded clothing (accelerated by today’s fast fashion?) and their eventual decomposition could be leading to more EDCs in the environment and eventually, into our water supply.
While risks of EDCs in clothing have not been quantified, this does not mean regulators are not acting. In the European Union, BPA has been restricted as a substance on its own and in mixtures intended for consumer use in the EU since 2018. In 2020, the EU implemented restrictions on 33 substances classified as carcinogenic, mutagenic, or toxic for reproduction (CMR) in textiles and footwear. These substances include phthalates and other chemicals. France and Sweden have proposed to restrict over 1000 skin sensitising chemicals in clothing, footwear and other articles that have contact with the skin. Bisphenols that have been identified as skin sensitisers would be included in this restriction if it were adopted.
Minimizing Risks
With EDCs everywhere, and unclear (but likely low) risks from exposure to athletic wear, it’s not clear what we can do to meaningfully reduce our overall exposure, even if we could find and wear clothing without EDCs. Given detecting EDCs is impossible for the consumer, we are left with making decisions that have to be based on the best available evidence and our current assessment of risk. It’s worth nothing that there is no question about the benefits of exercise, which are demonstrated and significant, which certainly outweigh any potential risk of EDCs. However, if you want to exercise and reduce any potential EDC exposure risk in your clothing, you could consider the following:
Wash new clothing before wearing – This will help reduce EDCs (and put them in the water supply).
Wear natural fibres – Natural fibre-based clothing made from cotton and wool seem less likely to contain (but may not be totally free of) EDCs.
Read the label – Look carefully at claims of stain- wrinkle- odor- and water resistance. This likely signals the addition of EDCs to the fabric.
Remove wet/saturated athletic gear after use – The substances in our sweat may ease the absorption of EDCs, so reducing their contact time with our skin may be helpful.
Conclusion
While the presence of EDCs in athletic wear may sound alarming, it does not mean you’ll be better off discarding all your gear – or not working out at all. A wardrobe of natural textiles may not be feasible or possible – and if even if you have one, the degree to which it reduces your total exposure to EDCs (and your risk) is unclear. However, ultimately, removing EDCs from clothing and other consumer products is likely better for society overall, if only because it will remove the total amount of these chemicals that are being created (and will eventually enter our food and water supply).