Hazardous Chemicals Found in Popular Hair Extensions

Study uncovers cancer-linked substances in synthetic and human hair products

Published on Feb. 27, 2026

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A new study by the Silent Spring Institute has found dozens of potentially harmful chemicals in widely sold hair extensions, including those made from human hair. Researchers detected substances linked to cancer, hormone disruption, reproductive harm, and immune system effects in nearly every sample tested, including flame retardants, phthalates, pesticides, and organotins. The findings raise concerns about the health risks, particularly for Black women who use these products at much higher rates.

Why it matters

Hair extensions have become increasingly popular, with over 70% of Black women reporting using them at least once in the past year. However, the beauty industry has long overlooked the health impacts of these products, leaving consumers unaware of the potential risks from prolonged exposure to hazardous chemicals. This study adds to growing evidence that stronger regulation and oversight is needed to protect public health, especially for vulnerable populations.

The details

Researchers purchased 43 popular hair extension brands and used advanced chemical analysis to identify over 900 chemical signatures, representing both known and previously unidentified compounds. They detected 169 chemicals spanning nine major structural classes, including many substances associated with cancer, hormone disruption, developmental harm, and immune system effects. Key findings include the presence of 48 identified chemicals on major hazard lists, 12 of which are listed under California's Proposition 65 for causing cancer, birth defects, or reproductive harm. The study also found four different flame retardants, 17 chemicals connected to breast cancer, and nearly 10% of products containing toxic organotins at levels exceeding EU health-based limits.

  • The study was published in the American Chemical Society journal Environment & Health in February 2026.

The players

Silent Spring Institute

A non-profit research organization focused on environmental health and the links between chemicals and disease.

Dr. Elissia Franklin

The lead author of the study and a research scientist at the Silent Spring Institute.

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What they’re saying

“While prior reports have found some chemicals of concern in hair extensions, there's still much we don't know about their overall chemical makeup. We wanted to get a better picture of the extent of the problem.”

— Dr. Elissia Franklin, Research Scientist, Silent Spring Institute (American Chemical Society journal Environment & Health)

“These findings make clear that stronger oversight is urgently needed to protect consumers and push companies to invest in making safer products.”

— Dr. Elissia Franklin, Research Scientist, Silent Spring Institute (American Chemical Society journal Environment & Health)

What’s next

Lawmakers in New York and New Jersey have introduced legislation that would require manufacturers of synthetic braids and hair extensions to disclose all ingredients and prohibit certain harmful chemicals. At the national level, the Safer Beauty Bill Package introduced in Congress last year contains provisions that would direct the FDA to regulate the safety of these products.

The takeaway

This study highlights the urgent need for greater regulation and oversight of the hair extension industry to protect public health, especially for Black women who use these products at disproportionately high rates. Consumers should be aware of the potential risks and push for more transparency from manufacturers about the chemical composition of these widely used beauty products.