"A friend told me that she gets a rash when she wears jeans. Can you be allergic to the blue dye in jeans?", asks Gerard Content, a loyal reader of Science and Future, on our Facebook page. This is our Question of the Week. Thank you all for your participation.
Yes, you can develop allergies from contact with clothing, and even shoes. "Cases of allergies and skin irritations linked to clothing or shoes are regularly reported", wrote in a reportNational Agency for Health Security (Anses) in 2018. This is why it recommends that consumers wash, before wearing it for the first time, any clothing likely to come into contact with the skin. The Agency also advises, in the event of irritation or allergy after purchasing clothing or shoes, to consult a doctor or dermato-allergologist to identify the possible substance responsible.
Chemicals causing contact dermatitis
To identify chemicals that could cause allergies and skin irritations, ANSES conducted a review of the scientific literature on the subject in 2018 and carried out tests on a sample of new clothing taken from several points of sale and shoes that had led to customer complaints. In total, around twenty families of chemicals were searched for in clothing and around fifty substances in shoes.
"These analyses made it possible to adjust the families of chemical substances to be searched for and to confirm, among other things, the presence of nonylphenols (editor’s note: endocrine disruptors), nonylphenol ethoxylates or formaldehyde (editor’s note: carcinogenic). They also made it possible to identify substances not routinely analyzed, which could cause contact dermatitis. (read the box below, editor’s note) such as 1,4-paraphenylenediamine or organotin derivatives, or azo dyes", details the Agency.
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In addition, ANSES analyzed items worn by about thirty patients of allergists and suspected of being associated with their skin reactions. The following are suspected of causing these symptoms: benzidine (carcinogenic), chromium 6, nickel, 4-tertbutylphenolformaldehyde resin (carcinogenic) and azo dye, widely used in the textile industry.
There contact dermatitis is an inflammation of the skin that occurs when it comes into contact with an irritant or allergen. It can occur rapidly or after prolonged and repeated exposure. It mainly occurs in two forms:
- there irritant contact dermatitis : it is most often caused by chemicals and can affect anyone. The symptoms it induces are redness, itching, sometimes cracks or blisters.
- there allergic contact dermatitis : it is the result of an allergic reaction after sensitization to a substance. It can be induced by nickel, cosmetic products, or textile dyes. It is recognizable by the following symptoms: red rash, intense itching, blisters, swelling, sometimes a burning sensation.
The diagnosis is made by a dermatologist. It is recommended to avoid contact with the irritant or allergen. Corticosteroids can reduce inflammation, antihistamines can relieve itching.
Set or lower thresholds to reduce allergic reactions
In 2018, ANSES recommended that the authorities lower the regulatory threshold for chromium 6 in leather goods, as it noted allergic reactions below the regulatory value, and set a threshold for nickel in textiles. To date, these recommendations have not been followed.
The Agency also asked those responsible for placing textiles on the market to check with their suppliers that their articles do not contain CMR substances (carcinogenic, mutagenic, toxic for reproduction) or skin irritants. Since 2020, the European Union has restricted the use of 33 CMR substances in clothing, textiles and footwear.
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