How to read a fabric label like a chemist

The label problem

Every garment you own has a fabric label. It lists fiber content: 88% polyester, 12% spandex. Maybe it includes washing instructions. Maybe a country of origin.

What it doesn't list: the fluorinated water-repellent coating. The antimicrobial silver treatment. The plasticizers incorporated during fiber extrusion. The disperse dyes that may contain benzothiazole. The formaldehyde resin used to prevent shrinkage.

This is the gap between what a label legally requires and what a chemist would actually want to know. For activewear founders, understanding this gap is no longer optional. Regulatory pressure is accelerating. Consumer awareness is sharpening. And the compounds hidden behind a simple "polyester" declaration are increasingly finding themselves in headlines, lawsuits, and banned-substance lists.

If you're building a brand, here's how to read a label with a chemist's eye.

What a fabric label is actually required to disclose

In most markets, textile labeling laws require two things: fiber content (by percentage) and care instructions. That's the baseline.

In Canada, the Textile Labelling Act mandates disclosure of the generic fiber name and the percentage by mass. In the United States, the Textile Fiber Products Identification Act requires the same, plus country of origin. The EU has Regulation (EU) No 1007/2011 covering fiber names and percentages.

The garment label must be accurate if size and care instructions are used (this particular information itself is not mandatory but if disclosed must be accurate).

Notice what's absent from all of these: chemical finishes. Coatings. Treatments. Additives. Plasticizers. Dyes.

A label reading "100% nylon" tells you the base polymer. It doesn't tell you whether that nylon was treated with a PFAS-based durable water repellent (DWR), infused with antimicrobial silver nanoparticles, or manufactured using plasticizers that may contain BPA.

The chemistry hiding behind "polyester" and "spandex"

Let's break down what's actually happening inside common activewear fibers.

Polyester

Polyester is polyethylene terephthalate (PET). Over 60% of all clothing today is made from Polyester, however nearly all activewear and leggings contain synthetic fibers made from plastic. These materials include Polyester, a widely used fabric made from polyethylene terephthalate (PET).

The fiber itself is petroleum-derived. But the concerns extend beyond the base polymer:

• Plasticizers: Some polyester formulations incorporate plasticizers to improve flexibility. Many of these materials contain high levels of BPA, a known endocrine disruptor, along with other hormone disrupting chemicals.
• Disperse dyes: Polyester requires disperse dyes for coloration, some of which contain compounds like benzothiazole that studies have linked to skin uptake.
• Antimicrobial treatments: Many polyester activewear items receive silver-ion or triclosan-based antimicrobial treatments to reduce odor.

Spandex (elastane)

Spandex provides stretch. It's a polyurethane-based fiber. The manufacturing process may introduce:

• Isocyanates: Used in polyurethane synthesis.
• Softeners and lubricants: Applied during processing.
• Residual solvents: From the fiber extrusion process.

PFAS finishes

PFAS are most commonly found in activewear and outdoor gear, thanks to their ability to make fabrics water-resistant, stain-repellent, and moisture-wicking.

PFAS (per- and polyfluoroalkyl substances) are applied as a surface finish. They provide water, oil, and stain resistance. These substances contain carbon-fluorine bonds which are one of the strongest chemical bonds. This means that PFAS resists degradation when used and in the environment.

The problem: Certain PFAS are linked to negative effects on human health, for example, in reproduction, and can harm the development of fetuses, may cause cancer in humans, and are suspected of interfering with the human endocrine (hormonal) system.

Your label won't say "PFAS-treated." It might say "water-resistant" or "stain-repellent." Those marketing terms are your signal to investigate further.

Endocrine disruptors in textiles: what to look for

Hormone disruptors, also known as endocrine disrupting chemicals (EDCs), interfere with the body's natural hormone functions. These chemicals mimic, block, or alter hormone activity, leading to imbalances that can impact reproductive health, metabolism, and even mental well-being. Clothing is a significant but often overlooked source of hormone disrupting chemicals. Many synthetic fabrics are made from petroleum-based plastics and are treated with chemical finishes that are absorbed through the skin or inhaled.

The key compounds to understand:

BPA and BPS

Bisphenol A (BPA) and its substitute, Bisphenol S (BPS), are often found in plastic-based textiles. These chemicals mimic oestrogen in the body and have been linked to fertility issues, metabolic disorders, and immune system imbalances.

Phthalates

Phthalates are used in activewear and anti-odor clothing, printing inks. They function as plasticizers to increase flexibility. Phthalates make plastics more flexible and are found in some synthetic activewear. They are associated with a range of health issues, including endocrine disruption and increased risk of obesity and diabetes.

PFAS (the "forever chemicals")

The health implications of PFAS exposure are serious and well-documented. These chemicals are known endocrine disruptors, meaning they can interfere with your body's natural hormone functions. Research has linked PFAS to a troubling list of health problems, including liver and kidney disease, reproductive issues, thyroid disruption, and certain types of cancer.

The regulatory landscape is shifting

If you're sourcing activewear fabrics in 2026, you're operating in a regulatory environment that's moving faster than most founders realize.

United States

Jurisdictions across the nation have implemented measures to regulate PFAS chemicals in consumer goods. These include, but are not limited to, California, Colorado, Connecticut, Hawaii, Illinois, Indiana, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New Jersey, New Mexico, New York, Rhode Island, Vermont and Washington.

Washington Chapter 173-337-110 WAC: Reporting requirements for apparel intended for extreme and extended use made from leather, natural textiles, synthetic textiles, or technical textiles with intentionally added PFAS took effect January 2026. First reports are due January 2027. Apparel and accessories made from leather, natural textiles, synthetic textiles, or technical textiles may not contain intentionally added PFAS after January 1, 2027.

European Union

Europe is advancing PFAS regulation through both EU-wide measures and national legislation. EU REACH Annex XVII, Entry 79: Restrictions on PFHxA and related substances take effect in April 2026, adding to existing bans on C9-C14 PFCAs.

France

France has confirmed new national restrictions on PFAS-containing products that took effect beginning January 1, 2026. The requirements were formalized through Decree No. 2025-1376 of December 28, 2025, adopted as part of France's broader PFAS legislation passed in February 2025. Under the decree, the manufacture, import, export, and placing on the market of products containing PFAS above regulated limits will be prohibited in France.

Denmark

Denmark will ban the use of PFAS in clothing, footwear and certain consumer products with waterproofing agents beginning on July 1, 2026.

The patchwork of state-by-state and country-by-country regulations makes compliance complex. But the direction is clear: PFAS restrictions are expanding.

What certifications actually mean

Certifications are the closest thing to a chemist's stamp of approval on a label. But not all certifications test for the same things.

OEKO-TEX Standard 100

Certifications such as OEKO-TEX ensure that textiles are free from harmful substances. OEKO-TEX 100 tests finished products for a list of regulated and harmful substances. It covers heavy metals, formaldehyde, pesticides, and certain dyes. Recent updates have added PFAS to the restricted substance list.

GOTS (Global Organic Textile Standard)

The GOTS certification bans the use of PFAS. GOTS goes beyond chemical testing to include environmental and social criteria across the supply chain. It applies primarily to natural fibers (organic cotton, linen, wool).

bluesign

The bluesign PRODUCT label indicates that a product was made with materials assessed against bluesign's Criteria, which include restrictions on PFAS. It provides a reference point for identifying products made with independently assessed inputs.

GRS (Global Recycled Standard)

GRS certifies recycled content but does not inherently restrict chemical finishes. A GRS-certified recycled polyester garment may still carry PFAS or antimicrobial treatments.

A practical framework for founders

If you're sourcing activewear fabrics, here's how to approach the label gap:

1. Request the full finish schedule

Ask your mill or supplier for the complete list of chemical treatments applied to the fabric. This includes:

• DWR (durable water repellent) coatings
• Antimicrobial treatments
• Anti-odor finishes
• Softeners
• UV protection treatments

2. Request SDS (Safety Data Sheets)

For any proprietary finish or treatment, request the Safety Data Sheet. This will disclose the chemical composition at a level of detail that marketing materials don't provide.

3. Specify PFAS-free in your tech pack

Make PFAS-free a contractual requirement. Document it in your tech pack. Require written confirmation from the mill.

4. Test the finished product

Certifications test at specific points in the supply chain. But chemistry can be introduced at multiple stages. Consider independent lab testing of your finished garments. U.S.-based labs can test for PFAS, BPA, phthalates, heavy metals, formaldehyde, and azo dyes.

5. Understand the tradeoffs

PFAS-free water repellency exists, but it may require different care instructions or have reduced durability. Bio-based stretch fibers exist (this is what we built at Ohzehn: 76% bio-based nylon from straw, corn, and castor oil, with 24% bio-based stretch fiber), but they require specific mill relationships. Know what you're trading.

A worked example: a Vancouver founder reformulating leggings

Consider a hypothetical scenario. A founder based in Vancouver is launching a yoga leggings line. She's sourcing from a mill that provides nylon-spandex fabric with "moisture-wicking" and "anti-odor" properties.

Her first order is ready to ship. Then she reads that France has banned PFAS in textiles as of January 2026. She wants to sell into the EU eventually.

She goes back to her mill and requests the finish schedule. She learns the fabric uses a C6 fluorocarbon DWR (PFAS-based) and a silver-ion antimicrobial treatment.

Now she has a decision: reformulate before her first order, or proceed knowing she'll need to reformulate later for regulatory compliance.

The reformulation path: she requests a fluorine-free DWR alternative and eliminates the antimicrobial silver. The mill quotes a 6-week development timeline. Her launch slides by two months. But she enters the market with a product that's compliant with emerging regulations and aligned with consumer demand for cleaner activewear.

This kind of decision is happening across the apparel industry right now. Founders showing at the Metro Show (Western Canada's premier apparel tradeshow, held downtown) are asking these questions. Designers preparing for Vancouver Fashion Week are reconsidering their supply chains.

The city's apparel scene, anchored by brands like Lululemon and Arc'teryx in North Vancouver, has always had proximity to both performance and outdoor markets. Key advantages of working with apparel manufacturing in Vancouver include access to skilled pattern makers and sample makers, close proximity to textile suppliers and trim vendors, and expertise in diverse product categories, from activewear to streetwear.

That expertise now needs to extend to chemical transparency.

The absorption question

Why does any of this matter? Because when we sweat during exercise, our pores open, potentially increasing our exposure to these toxins. The fashion industry uses approximately 8,000 synthetic chemicals, many of which are known endocrine disruptors.

When these chemicals are used in clothing finishes, they don't just stay there. They can be absorbed directly through your skin, especially when you're sweating in tight-fitting activewear.

Skin is the body's largest organ. Nearly 20 square feet of absorptive surface. Highly vascularized. Dense receptor presence. The genital and thigh regions, where leggings make direct, prolonged contact, are particularly proximate to hormone-sensitive reproductive tissues.

Activewear is worn 12-16 hours a day. The issue is not acute toxicity. It's chronic, cumulative load. The difference between a one-time exposure and years of daily wear.

What the label can't tell you

A fabric label is a legal document, not a health disclosure. It tells you the fiber. It doesn't tell you the chemistry.

Until labeling laws catch up with chemistry, the burden falls on founders to ask the questions, request the documentation, and test the product.

When choosing activewear, it's important to be aware of potential harmful chemicals that might be present. BPA (Bisphenol A) is one such compound. It's typically associated with plastics but can also be found in clothing. This endocrine disruptor can be absorbed through the skin and is linked to hormone imbalances.

Reading a fabric label like a chemist means recognizing what's disclosed and what's hidden. It means understanding that "88% polyester, 12% spandex" is the beginning of the inquiry, not the end.

The old standard was aesthetic. The new standard is biological compatibility. Fabric is not neutral. It is part of your biological environment.

Dougie Taylor

Co-Founder, Ohzehn Textiles · Building plastic-free performance apparel