A recent investigation by Which? found that some period pants from popular UK brands contain silver, which is sometimes used as an antimicrobial agent, but has been linked to health and environmental concerns.

Which? bought period pants from major brands including Bodyform, M&S, Modibodi, Primark, Sloggi, Superdrug, Thinx, Uniqlo, and Cool Period. They worked with Italian consumer organisation AltroConsumo to test the products for silver, which they could detect if it was present at levels above 0.1mg per kg.

Silver was found in products from 7 brands and the highest levels were found in Bodyform and M&S period pants. Essity who owns Bodyform told Which? “our collection also includes ranges that are without an antibacterial property for those who prefer an alternative”.

M&S did not respond to Which?’s request for comment. See the full set of results and responses here.

No silver was detected in Primark, Repeat, Wuka, Lovable and Sloggi pants (although Sloggi’s website states that it uses a silver-based antimicrobial and Primark told Which? it uses silver chloride), indicating that safer alternatives are available.

Silver is sometimes added to period pants as an antimicrobial agent, which brands may use to address user concerns about their period pants smelling. The type of silver in period pants is different from silver you may find in jewellery and may include nanosilver and various silver containing substances (e.g. silver zeolite, silver copper zeolite, silver zinc zeolite, or silver chloride).

There is currently insufficient research into the health impacts of these forms of silver on human health, and there are no UK legal limits on levels of silver permitted in textiles. However, the Food and Drug Administration (FDA) who are the U.S. regulator responsible for protecting public health, previously raised concerns about nanosilver potentially killing healthy bacteria, which Women’s Voices for the Earth suggest may increase the risk of bacterial vaginosis, STIs and pregnancy complications.

The European Chemicals Agency has identified silver zinc zeolite, a substance sometimes used in period pants, as potentially toxic to reproduction and toxic to aquatic life (depending on the concentration).

Previous studies have found endocrine disruptors, including certain phthalates, bisphenols, fragrances and PFAS in conventional, disposable period products and PFAS have also been found in reusable period pants. Which? stated that they did not find PFAS in any of the products that they tested.

Exposure to endocrine disruptors has been linked to a variety of health concerns including reproductive and fertility problems, endometriosis, certain hormonal cancers, early puberty and diabetes. This is particularly concerning because period products are often used in a sensitive area, for extended periods of time.

The good news is that safer alternatives are available. For example, using menstrual cups, reusable fabric pads, or period pants from brands that do not contain harmful chemicals may reduce your risk of exposure. For more information on reusable menstrual product options read the Women’s Environmental Network’s guidance here.

See our Instagram post for more information about alternatives. You can also find more information and advice in our guest blog for the Women’s Environmental Network (Wen) and on our ‘reduce your risk’ webpage here.

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