Hair extensions may contain chemicals linked to cancer and reproductive problems
A new study finds that different types of hair extensions — from natural to synthetic — contain chemicals linked to cancer, birth defects and reproductive problems.
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There can be dozens of hair extensions, including artificial and natural braids They contain synthetic chemicals that are a threat to health and the environmentA new study shows. At least 12 of the 169 chemicals found in the new analysis are linked to cancer, birth defects and reproductive problems and are included on California’s Proposition 65 list of hazardous chemicals.
The study, published today Environment and Health, 43 hair extensions were tested, including extensions made from synthetic hair, as well as untreated “raw” human hair and other biobased hair, such as hair made from banana-based fibers. All but two products contained hazardous chemicals and about 10 percent of them contained hazardous chemicals. organotin compounds-Synthetic chemicals associated with endocrine-disrupting effects. The concentrations of some were above EU limits. However, the study’s authors say more research is needed for government agencies to determine whether the chemical levels found in these products require more regulation.
“Each of the hazardous chemicals we identified has its own risks,” says Alicia T. Franklin, lead author of the new paper and a research scientist at the nonprofit research organization Silent Spring Institute. “Our findings show that these products can expose (people) to multiple chemicals over time, and through repeated use, these combined risks increase.”
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more than this 70 percent black women in America. Use hair extensions at least once per year, including hairstyles like braiding – a key part of many Black cultures that have been shaped by the slave trade, colonialism and Western beauty standards. Chemical relaxers – another product commonly used to style black hair – used to permanently straighten previously curly or kinky hair Linked to higher risk of uterine cancer.
“On one hand, I’m excited to get to work and share this new knowledge with the world,” says Franklin. “On the other hand, I’m learning that this new information leans toward the idea that my community is deeply polluted with harmful chemicals, even down to practices that are embedded in the culture, like braiding.”
Using a chemical library, Franklin’s team detected more than 900 chemical signatures ranging from hair extensions to dozens of potentially harmful compounds. In synthetic hair samples, they found chlorine levels as high as 277,000 micrograms per gram. The Centers for Disease Control and Prevention reports that exposure to 60 micrograms per gram of chlorine, a flame retardant, for 60 minutes or longer through inhalation is harmful. May cause irritation and impaired lung function. Researchers also found small traces of fluorine in some samples, a chemical that can reduce birth rates in high doses, as well as organohalogens and nitroaromatics – both known to have carcinogenic effects.
However, the study did not determine whether any particular amount of chemical exposure from hair extensions was above legal standards or would necessarily cause health problems in people. Franklin says this limitation makes it difficult to create safety guidance. But the work is in line with a growing trend: A 2022 study found traces of potential Harmful Heavy Metals in Synthetic HairAnd Consumer Reports’ 2025 analysis found that Hair extensions used when braiding contain volatile organic chemicals—which can cause irritation as well as irritation to the eyes, nose, and throat Possible long-term kidney and liver damage.
In the new study, “the detection of more different classes of potentially harmful chemical contaminants is evidence that these products contain more chemical types than our findings suggest”, says James Rogers, director of product and food safety research and testing. consumer ReportsWho led the 2025 analysis. He was not involved in the new newspaper.
Biobased hair products, such as those made from silk or banana-based fibers, are generally a better choice than other extensions. But the study found that some biobased extensions labeled as nontoxic contain unclassified complex chemicals. Although those chemicals may not be dangerous, Franklin advises caution: “Biobased doesn’t automatically mean safe.”
Editor’s note (2/11/25): The image in this article was changed after posting. The caption of the original image mistakenly labeled natural hair as hair extensions.
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