A study of school uniforms in the United States and Canada reveals high levels of so-called “forever chemicals”.
The chemicals, known as PFAS, are used to make clothes resistant to stains or water but have been linked to asthma, obesity and fertility issues.
Researchers found that uniforms made with 100% cotton showed higher levels than synthetic materials.
The scientists may increase the long-term health risk if children are exposed to these chemicals.
The issue is less in the UK as almost all retailer brand uniforms are PFAS-free, campaigners say.
From firefighting foam to food packaging and textiles, PFAS chemicals are widely used due to their non-stick and water-resistant properties.
But researchers have long been concerned about these chemicals, known as per- and polyfluoroalkyl substances – because they don’t break down under normal environmental conditions.
The “forever chemicals”, which number in the thousands, are still in soil and water. However they can also accumulate in the human body when ingested.
Although the direct evidence linking them to health problems is mixed, scientists are concerned about exposure, especially among young people whose lower body weight and sensitive development may pose a greater life threat.
This latest study focuses on exposure to the chemicals that may occur from wearing school uniforms.
It is estimated that approximately 20% of children in the US and Canada wear uniforms, both in public and private schools.
“All these clothes that we focused on were polo shirts and khaki pants, the normal uniforms, but they were specifically marketed as stain-resistant,” said lead author Dr. Marta Venier of Indiana University. on the study.
“So we were selective about picking clothes that were labeled as stain-resistant. And what we found was that PFAS was present in all of these items.”
The researchers looked at total fluorine levels in the products to indicate the presence of PFAS. They found that the school uniform samples had higher levels than the outdoor recreation-resistant ones.
Products made from 100% cotton outnumbered synthetic products. Scientists believe this is because synthetic items have higher water and stain resistance.
The researchers admit that their study is small, involving 72 samples of products labeled as water or stain resistant. The researchers also don’t know how or if the PFAS in clothing gets into children’s bodies.
“We are chemists, not toxicologists. So we usually try not to go into realms where we don’t need them,” said Dr. Venier.
“But we know that PFAS is a health concern, so the idea that children are wearing clothing, which can continuously release these substances, is a concern,” she said.
Due to the growing concern about PFAS some of the chemicals are banned in the UK and EU.
In the UK, the environmental charity Fidra is leading a campaign to make retailers aware of the presence of PFAS in school uniforms.
“ had people who bought uniforms, with these coatings, washed them more often, and replaced them just as much as people who did not buy the ones made stain-resistant,” said Dr Clare Cavers, senior project manager at Fidra. .
“The stain resistant coatings came off uniforms after 10 to 20 washes. So if they were buying the uniform for that purpose, it wasn’t making any difference.”
As a result of their efforts, all major retailers in the UK sell their own brand school uniforms free of PFAS, Dr Cavers said.
The move to eliminate PFAS from clothing and textiles is gathering pace with California phasing out sales from 2025. The EU is also looking at a ban and the UK is also examining the idea as part of a chemical waste strategy -Brexit.
The study was published in Environmental Science and Technology Letters.
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