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26th August 2025
Chemical free school uniform choices
As children prepare to go back to school many will need new uniforms. But what’s the best choice for parents to make?
It’s a mix of price, durability, and sizing up how long they’ll last before their children outgrow them. Retailers complete for parents’ attention at this time of year by developing products that appeal to parents concerns about wearability and durability. This includes ‘stay new’ fabrics, scuff resistant shoes, and fabrics with stain resistance so clothes stay clean and look smarter for longer.
But what’s the technology behind them?
Being curious about the use of chemicals in everyday, sometimes unsuspecting places, we contacted some major UK retailers to ask for advice about these product claims, and whilst it took a while for them to respond, we discovered that ‘stay new’ is a technology where natural processes are capitalised to achieve improved fabric performance. In one example, this is achieved by using enzymes that work on the fabric surfaces to maintain a smoother handle for longer with less “bobbling”.
We had to dig deeper on the question of stain resistance – some manufacturers make claims, but not are fully explained. We discovered that brands who include Teflon EcoElite™ in their product description make it easier for consumers to learn more about stain resistance.
Teflon’s website states that their “biobased finish is durable and made with non-GMO renewable resources and [ ] this non-fluorinated product has been recognized as a USDA-certified biobased product, because it’s made with 60% renewably sourced content from plant-based raw material.” So broadly speaking, this means fewer chemicals have been used in the manufacturing process to achieve longevity of fabrics than previously.
We also asked a leading UK retailer of school uniform about stain resistant fabrics, and following a long [personal] email exchange they shared with us:
“Concerning the properties of the fabric we can disclose that at Marks & Spencer we do not use PFAS chemicals in the manufacturing and finishing of any of our clothing products. Our school t-shirts, trousers and skirts are created with care and finished with a fluorine-free preparation which repels water and water-based stains. This ensures our market leading school wear continues to be ‘hand-me-down’ quality which is made to last.”
They also shared a link to their chemical management policies. It’s a fairly deep dive, but confirms that PFAS is not used in M&S school uniform manufacture – great news!
This is a positive move away from older fabric technologies that rely on potentially harmful chemicals including PFAS, but it’s not easy to find guidance about how long these treatments will last. A survey carried out amongst parents who chose stain resistant clothing found that children were more likely to outgrow clothes before any finishes wore off.
Chemical use in clothing
Chemicals have been used in clothing for decades and more than 8000 synthetic chemicals are now used in clothing, that’s 62% of all fibres used. 25% of global chemical output originates in the fashion industry. It’s not always easy to identify any chemicals used to manufacture clothes, and any potential hazards they might pose to your wellbeing.
All synthetic fibres are derived from petrochemicals and fall into 4 primary groups – polyester (the most common) acrylics, nylon, and Lycra. The most widely used in school uniforms is polyester, manufactured using the thermoplastic polymer polyethylene terephthalate (PET).
Polyester has a high wear resistance and is easy to wash. However, PET has become a major source of plastic pollution and polyester samples tested were found to contain antimony at detectable levels, a known carcinogen. Microplastic particles of fibres originating from synthetic fibres have been detected in air samples collected in Geneva, highlighting their potential to enter the body by inhalation. Regular exposure to polyester fabrics such as clothing, sportswear, and bedding might also present a health risk through skin contact.
Waterproof and stain proof clothing
Teflon and Perfluorochemicals (PFCs) are used in the manufacturing process by some clothing brands to add durability, water and stain resistance, and wrinkle free (non-iron) effects to clothing. Others rely on per- and polyfluoroalkyl substances (PFAS), used for its water and stain resistance properties. PFAS are known as ‘Forever chemicals’ because of their hard to break chemical chains that persist in the environment forever. PFAS enters the water and food chains, where they can enter into the body and have endocrine disrupting health effects.
PFAS are still used by some children’s clothing brands, including school uniforms and outerwear, but other leading brands including, H&M and Levi have removed them from their manufacturing processes due to health concerns. There is an industry wide call to ban PFAS in Europe. If you are concerned, ask for more information about chemicals used in school uniform production processes.
Can synthetic chemicals in clothing be absorbed into the body?
Skin is the body’s largest organ, and body heat enhances the release of chemicals from synthetic fibres and aids absorption into the body. Forever chemicals (PFAS) can penetrate the skin suggesting a new pathway for this vast group of chemicals to enter the bloodstream. Studies have found that clothing can expose us to harmful chemicals by skin contact. The effects are not fully understood yet, but levels detected are described as “non-negligible” but raise questions about potential cancer risks for wearers.
How to reduce exposure to chemicals in clothing
Most cotton fibres are free of synthetic chemicals, but they may still be used in the manufacturing process. Environmental toxins can lurk in both polyester and cotton fabrics, even organic cotton, from chemicals that may have leached into the water course. Most cotton is grown using pesticides whilst organic cotton is grown without them, but it’s worth checking if any surface treatment has been added such as stain resistance, and if so, whether it is derived from plant origins such as Teflon EcoElite™.
If you are concerned about chemicals lurking in your children’s clothes, choose garments made with natural fibres such as organic cotton, bamboo, and wool. If they have been treated for stain resistance or durability, check with the retailer how this has been achieved.
- Wear natural fibres against the skin if the top layer has been waterproofed, including footwear.
- Avoid printed graphics on children’s clothing and socks as some have been found as a source of exposure to benzothiazoles (BTHs) and benzotriazoles (BTRs). These chemicals are classed as “probably carcinogenic” by the IARC.
- Synthetic clothing releases thousands of microplastic particles during a washing cycle, so separating textiles that might rub against each other such as denim can help reduce what escapes into your wastewater. Washing at lower temperatures can also help.
- Guidance on how to reduce microplastics in your washing.
- Tumble drying clothes also accelerates the release of microplastic particles, so air dry where possible.
- Sign up for our NEW Everyday Chemicals Test to learn more about your exposures to 27 different chemicals from a. single urine sample.
Further reading
- A closer look at what’s in synthetic clothing.
- Organic cotton
- Sustainable Fashion for the earth
- Shop clothes sustainably guide
- How to reduce shedding microplastics from your laundry.