Forever chemicals in school uniforms: what the research found

In 2022, researchers from Indiana University and the University of Notre Dame published a study that made headlines across North America. They wanted to know whether children's clothing, and school uniforms in particular, could be a meaningful source of exposure to PFAS.

The answer was yes.

What are PFAS?

PFAS (per- and polyfluoroalkyl substances) are a family of thousands of human-made chemicals. Their carbon-fluorine bonds are among the strongest in chemistry, which makes them brilliant at repelling water, grease and stains. It also means they barely break down, in the environment or in our bodies. That's why they're nicknamed "forever chemicals".

PFAS have been used since the 1940s in non-stick pans, food packaging, firefighting foam, carpets and clothing. Some PFAS have been associated in research with health effects including thyroid disease, hormone disruption, reduced immune response and certain cancers.

What the uniform study found

The researchers bought 72 children's textile products marketed as stain-resistant from US and Canadian stores, focusing on school uniforms like polo shirts and khaki trousers. Key findings:

• PFAS were detected in every product tested.
• School uniforms had significantly higher PFAS levels than bibs, hats, stroller covers and swimsuits.
• Uniform levels were comparable to outdoor wear such as rain jackets, a category usually associated with these chemicals.
• The most common compound was 6:2 fluorotelomer alcohol, which the authors noted could also be inhaled.
• Surprisingly, 100% cotton uniforms had higher PFAS levels than synthetic blends.

That last point matters. It shows the issue isn't cotton versus polyester. It's the stain-resistant treatment applied afterwards. A cotton shirt can be loaded with PFAS if it's been finished to repel stains.

Why children's exposure is a concern

The study's authors pointed to two reasons for extra caution with kids. Children have lower body weight, so the same exposure means a higher dose per kilogram. And uniforms are worn directly against the skin for many hours a day, five days a week.

The researchers estimated a median potential skin exposure of about 1 nanogram per kilogram of body weight per day from uniforms alone. That's a small number, and the researchers were clear that uniforms are only one of many sources. But because PFAS accumulate, every avoidable source counts.

Does this apply in Australia?

The study tested products from North American stores, so we can't say Australian uniforms contain the same levels. What we do know is that stain-resistant uniforms are sold here too, and that PFAS-based finishes are used in textiles globally. Australia banned three specific PFAS (PFOS, PFOA and PFHxS) from 1 July 2025, but the main compound found in the uniform study is not one of the three. We cover the Australian rules in more detail later in this series.

What you can do

• Skip the stain-resistant label. Words like "stain-guard", "stain-release", "soil-resistant" or "water-repellent" can signal a fluorinated finish.
• Ask the supplier. Uniform shops and brands should be able to tell you whether a PFAS-based treatment was used.
• Look for certification. The Global Organic Textile Standard (GOTS) bans PFAS in certified products.
• Accept a few stains. As one of the study's authors put it, most parents would rather wash a shirt again than expose their child to unnecessary chemicals.

At Natural Schoolwear, our uniforms carry no stain-repellent treatments. A grass stain or a splash of tomato sauce is a small price for peace of mind.

Source: Xia et al., "Per- and Polyfluoroalkyl Substances in North American School Uniforms", Environmental Science & Technology, 2022.