Meet the Toxic Chemicals That Are Lurking in Your Yoga Pants

Our friends at Shape Magazine tell us how harmful chemicals in our prized yoga leggings could be hurting rather than helping our health.


We consumers are good at telling brands what we want—and getting it. Green juice? Virtually non-existent 20 years ago. Mainstream organic skincare and makeup that actually works? Popped up in the noughties. Alternatives to plastic water bottles? Hello, Bkr. It's no surprise Whole Foods has more than 400 stores. Our hard-earned dollars demand healthy, better alternatives, and the market has started supplying them.

And now, we look smoking hot while we strive to be our healthiest selves, because workout clothes have become off-the-hook gorgeous. Function and fashion have merged to form a new breed of figure-flattering, high-performance activewear—for all budgets and body sizes. In fact, workout clothes are the daily uniform for a growing number of women, according to global information company the NPD Group. We've swapped our skinny jeans for yoga pants, athleisure is officially a thing, and our lust for stylish gear is single-handedly buoying fashion sales. (See the 10 Best Instagram Accounts to Follow for Athleisure.)

But therein hides the blind spot in our otherwise noble quest for a life healthily lived. We buy the cleanest products and food we can, avoid toxins where possible and exercise, but are the workout clothes we wear while doing all this undermining our efforts?

The findings from two Greenpeace reports on chemical content in sportswear and fashion suggest they might be. Their analysis found that sportswear from major brands contained known hazardous chemicals, like Phthalates, PFCs, Dimethylformamide (DMF), Nonylphenol ethoxylates (NPEs), and Nonylphenols (NPs). And a Swedish study estimates that ten percent of all textile-related substances are "considered to be of potential risk to human health."

In an article exploring toxic chemicals in sportswear, published by The Guardian, Greenpeace's Manfred Santen suggests we can't know the effects of these chemicals and how repeated exposure to them might affect us. "The concentration [of chemicals] that we find in clothing may not cause acute toxic problems for the wearer in the short-term, but in the long-term you never know," Santen said. "Endocrine disruptors [chemicals that can mess with the hormone system], for example, you don't know what the impact of long-term exposure is on human health."

This is new territory. There is little research on the topic (although it's growing), and right now many industry insiders dismiss this line of inquiry as a non-issue. We're reluctant to look our Spandex-clad gift horse in the mouth. Afterall, business is booming and we look so good that no one wants to return to the days before activewear brands knew the value of a well-placed dart.

The potential presence of harmful chemicals in any amount our workout gear, however, should be troubling in large part because it's designed to sit against and interact with the skin in high-friction, high-movement, high-heat, high-moisture environments—like when we work out. Independent Swiss company bluesign technologies—creator of the toughest textile certification system, which aims to prevent chemicals of concern from entering into materials in the manufacturing process—puts clothing for "next to skin use" and "baby-safe" in the same category, their "most stringent" one "concerning [chemical] limit values/bans."

Yet, retailer REI says that "some type of chemical finish is applied to nearly every synthetic fabric in order to boost wicking performance." A look at the tag in activewear garments reveals most are fashioned from synthetic fabrics. Plus, most trademarked technical fabrics—the ones we pay major bucks for—are chemically coated synthetic fabrics, says Mike Rivalland, director of activewear brand SilkAthlete. Santen agreed, telling us that "the bigger problem is that brands use additives to make gear stain repellent with per-fluorinated substances (PFCs) or to avoid unpleasant sweat odors by using toxic substances like Triclosan."

But don't despair. Adam Fletcher, Patagonia's global director of public relations, points out how difficult it would be to absorb a harmful level of some chemicals in question through the skin. "Wearing [a] jacket does not offer a significant risk of exposure," he says. "If one were to eat a closet-full of jackets, maybe then you would get on par with the exposure risk from food contact applications of these chemicals."

Some big brands are taking action, though, sourcing high-performance organic fabrics and recycled materials, and seeking natural alternatives to chemical finishes. Patagonia has invested in Beyond Surface Technologies, which develops "textile treatments based on natural raw materials" and is phasing out PFCs, similar to Adidas, which has promised that their products will be 99 percent PFC-free by 2017. Both brands partner with bluesign technologies, as do REI, Puma, prAna, Marmot, Nike, and Lululemon.

Smaller brands have also been producing outstanding non-toxic activewear with high-tech traits we demand. Ibex specializes in organic cotton and merino wool activewear. Evolve Fitwear only sells American-made gear with organic cotton (like LVR's 94 percent organic cotton leggings) and recycled materials. Alternative Apparel's soft, slouchy basics in organic and eco-fabrics easily transition from yoga to brunch. SilkAthlete's stylish silk-blend garments are not only naturally breathable and antimicrobial, they feel light as air and don't chafe like synthetic fabrics can. And Super.Natural makes high-performance, flattering workout clothes from engineered natural-synthetic fabrics hybrids. And these companies are a step ahead of the game in our highly health-aware, eco-concious culture. (And check out this Sustainable Fitness Gear for an Eco-Friendly Workout.)

What's Lurking In Your Yoga Pants?
Below, we rounded up some of the potentially hazardous chemicals that could be in your workout clothes—plus, why you should care.

Phthalates: Commonly used as platicizers in textile printing (found in tons of consumer goods), they're linked to certain cancers, adult obesity and reduced testosterone in men and women, and are on the Environmental Working Group's Dirty Dozen list.

PFCs (poly- and per-flourinated chemicals): Used in water- and stain-proof gear. Clothing is one of the most common ways we're exposed to them, according to The EWG, which classifies them as toxic to humans.

Dimethylformamide (DMF): The CDC says DMF is "an organic solvent used in acrylic fiber spinning, chemical manufacturing... It is also present in textile dyes and pigments..." It warns people to avoid skin contact with the chemical as it's easily absorbed through the skin and "can cause liver damage and other adverse health effects."

Nanoparticle silver: Used in anti-odor and antimicrobial activewear but not tested for safety in consumer goods, says Pew Charitable Trust. A 2010 study found "exposure to silver would be 'significant' for anyone wearing these clothes, in an amount that's three times higher than the amount you'd get if you take a dietary supplement that contains silver." A 2013 study links nanomaterials to potential endocrine disruption and a 2014 MIT study found nanoparticles can damage DNA.

Nonylphenol ethoxylates (NPEs) and Nonylphenols (NPs): Used in detergents and dust-control agents. According to the CDC, they're absorbable through the skin and shown to have "estrogenic properties in human cell lines". The EPA says they're "associated with reproductive and developmental effects in rodents" and they wreak havoc on the environment. The European Union classifies them as "reprotoxic."

Triclosan: Used as a coating in antibacterial and antimicrobial garments and gear, triclosan has been linked to liver and inhalation toxicity and has been shown to cause liver cancer in mice.

Buy Less Toxic Workout Clothes
If you want to avoid some of the nastier things found to fitness gear, follow our tips for a "cleaner" workout wardrobe.

  • Avoid screen printing and plastic prints, a potential source of phthalates.
  • Buy natural and organic fabrics (or hybrids) like silk, cotton and wool. Natural fabrics are naturally antimicrobial and antibacterial, good at thermal regulation, and breathable.
  • Seek the bluesign System certification. The bluesign label means hazardous chemicals are kept to a minimum (and are potentially absent) during manufacturing and in the end product.
  • Pass on trademarked technical "fabrics"—most are chemically coated synthetics that wash out.
  • When will you use it? If you're wearing something against your skin all day, invest in a piece with as few potentially hazardous chemicals as possible.

Wash Them Smarter
Whether you have a closet full of silk sports bras or you don technical fabrics 24/7, keep your fitness gear clean, intact, and functional for as long as possible.

  • Wash every item before use. Santen says, "washing removes adherent substances that could be potentially hazardous."
  • After a super sweat-inducing workout, wash clothes immediately. Synthetic fibers, particularly polyester, are breeding grounds for stink-producing bacteria.
  • Hand wash or use the gentle cycle on with cold water so garments aren't destroyed by high heat or agitation.
  • Line dry or lay clothes flat to dry. Some brands say using the lowest-heat dryer setting is fine, but anything hotter will break affect the coating on technical fabrics and could harm synthetic (i.e. plastic) fabrics, like Lycra, which becomes brittle if dried with high heat.
  • Use gentle wash or specialized wash. Harsh detergents can ruin or wash out properties for which you bought a garment in the first place, and sports wash helps break down oily sweat and odor buildup. (Try one of these 7 Safer All-Natural Homemade Cleaners.)
  • Avoid fabric softener and dryer sheets. They work by leaving a film on the fabric, which ends up blocking the wicking/absorbing/cooling/anti-odor ability of the garment.

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