Researchers Raise Alarm Over Cancer Chemicals in Everyday Beauty Products

A body wash. A conditioner. A bar of hand soap used twice a day. None of them list a known human carcinogen on the label, yet all three showed up in one woman’s weekly product log carrying the same hidden ingredient. A new study just confirmed how common that pattern is across an entire community of women who had no idea what they were applying to their skin.

Silent Spring Institute researchers recruited 70 Black and Latina women in Los Angeles and had them photograph the ingredient list of every personal-care product they used over a full week. Sixty-four participants submitted usable data. The results, published in the journal Environmental Science & Technology Letters, became the first study to look at formaldehyde exposure across an entire daily beauty routine, not just hair products.

More than half, 53%, reported using at least one product containing formaldehyde or a formaldehyde-releasing preservative. Soap, lotion, shampoo, conditioner, skin lightener, eyeliner, and eyelash glue all turned up on the list. “It’s really concerning that we are intentionally putting chemicals that release a carcinogen into our products that we apply to ourselves every day,” said lead author Robin Dodson.

The Danger Extends Far Beyond Hair Straighteners

For years, concern about formaldehyde in beauty products centered almost entirely on chemical hair relaxers. This study found the chemical hiding in a much wider range of everyday items, according to Columbia University’s Mailman School of Public Health, including products applied daily and covering far more skin surface area than a hair treatment ever would.

One participant logged three separate formaldehyde-containing products in a single week: a leave-in conditioner, a rinse-off conditioner, and a body wash. Another washed with formaldehyde-releasing hand soap roughly twice a day, every day. Neither product was marketed as a hair treatment, and neither ingredient label used the word “formaldehyde” anywhere on the packaging.

Across all 64 women, researchers counted 1,143 products used over seven days, an average of 17 different items per person per day. Some participants used as few as five, others as many as 43. “It speaks to the pressure women have to look a certain way,” said Tracey Woodruff, who directs UCSF’s Program on Reproductive Health and the Environment.

A Pattern Researchers Say Traces Back to Beauty Standards

Earlier research had already linked frequent use of chemical hair straighteners to higher rates of breast, uterine, and ovarian cancer among Black women compared to white women, a disparity that’s fueled thousands of product-liability lawsuits in recent years. This new study suggests hair straighteners may be only one piece of a much larger daily exposure pattern.

Janette Robinson Flint, executive director of Black Women for Wellness and a study co-author, connects the pattern to social pressure to fit narrow beauty standards. Researcher Tracey Woodruff went further, calling the exposure gap “part of the legacy and history of discrimination against the Black and Latinx population” in how beauty norms get defined and marketed.

Part of the problem is that formaldehyde rarely appears on a label by its own name. Manufacturers list formaldehyde-releasing preservatives under names like DMDM hydantoin, diazolidinyl urea, and quaternium-15, chemical terms that mean nothing to the average shopper scanning an ingredient list in a store aisle.

Two Years After a Promised Ban, Nothing Has Changed

In 2023, more than a decade after federal researchers first classified formaldehyde as a human carcinogen, the FDA tentatively planned to propose banning it in hair straighteners. Two years later, no such rule exists, and the agency declined to comment when asked about the delay. The European Union, by contrast, banned formaldehyde as a cosmetic ingredient back in 2009.

At least a dozen U.S. states, including California and Washington, have proposed or passed their own formaldehyde regulations in recent years. California’s Safe Cosmetics Program data shows some progress: a tenfold drop in products containing the chemical between 2009 and 2022. Whether that trend holds nationally, without stricter federal rules, remains an open question.

Dodson’s advice for right now is blunt: read labels and watch for the releaser names, even though they’re hard to spot. But she’s clear that’s a stopgap, not a fix. “In the longer term, I think there has to be a regulatory solution,” she said. “It has to come down to ingredient bans, likely at the state level.” Until that happens, the burden of decoding a carcinogen stays on the consumer.