More than half of Black and Latina women in Los Angeles who participated in a new study regularly used personal-care products containing a known carcinogen.
Study participants photographed the ingredient lists of all the products they used at home over the course of a week. The journal Environmental Science & Technology Letters published the study Wednesday.
Of 64 women, researchers found that 53% reported using soap, lotion, shampoo, conditioner, skin lightener, eyeliner, eyelash glue and other beauty products that contained formaldehyde and formaldehyde-releasing preservatives — toxins found to cause cancer in humans.
"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, associate director of research at Silent Spring Institute, a Massachusetts nonprofit studying environmental causes of breast cancer.
"Formaldehyde is a great preservative," she said. "That's why it's used as an embalming fluid. And we do have to remember formaldehyde is a carcinogen."
The study is among the first to demonstrate that formaldehyde-releasing preservatives are present in a wide range of beauty products.
The research, collected in 2021, focused on Black and Latina women after previous studies showed they are more often exposed to formaldehyde in nail and hair products than white women. Researchers have questioned whether African American women's frequent use of chemical hair straighteners, suspected of containing formaldehyde-releasing agents, might explain why breast, uterine and ovarian cancers kill disproportionately more Black than white women.
In 2023, a dozen years after a federal agency classified formaldehyde a human carcinogen, the Food and Drug Administration was tentatively scheduled to unveil a proposal to consider banning the chemical in hair straighteners. Two years later, the government still has failed to act. The FDA declined to comment.
The new study shows that formaldehyde and formaldehyde-releasing products are present not only in hair relaxers but in a wide variety of beauty products, including some that women apply to their bodies far more frequently than chemical hair straighteners.
One study participant used three formaldehyde products: a leave-in conditioner, a rinse-off conditioner and a body wash. Another participant washed with hand soap with formaldehyde-releasing agents an average of twice a day.
An array of products
The sheer number of products — 1,143 over seven days — the 64 participants used struck Tracey Woodruff, who directs the University of California at San Francisco's Program on Reproductive Health and the Environment. The women in the study used an average of 17 different products a day — as few as 5 and as many as 43.
"It speaks to the pressure women have to look a certain way," said Woodruff, who was not involved with the new research.
Social and economic pressures frequently compel Black women to alter their appearance to conform to white beauty standards, said study co-author Janette Robinson Flint, executive director of Black Women for Wellness. She called for government oversight of personal-care products. "We shouldn't have to be chemists to figure out what kinds of products will make us sick," she said.
"Beauty norms that focus on white presentation definitely are resulting in people using products that can be harmful to their health," Woodruff said. "This is part of the legacy and history of discrimination against the Black and Latinx population."
Woodruff would have liked the study to also compare product use by white women in an effort to assess whether beauty-product use is contributing to health inequities.
Woodruff and Dodson joined Flint in calling for government oversight and regulation of cosmetics and other personal-care products.
Banned in Europe
In addition to being a carcinogen, formaldehyde, a colorless and smelly gas, can cause rashes and can sicken those who breathe it in, according to the FDA. Formaldehyde-releasing products need not be listed as formaldehyde on ingredient labels. Instead, they are listed by their chemical names, such as DMDM hydantoin, short for 1,3-dimethylol-5,5-dimethylhydantoin, which, as Dodson noted, doesn't exactly roll off the tongue.
The European Union banned formaldehyde as a cosmetic ingredient in 2009, and any cosmetic product containing a formaldehyde-releasing preservative above a miniscule concentration must include a warning. At least 12 states, including California and Washington, have recently proposed or enacted laws to regulate the use of formaldehyde in cosmetics.
How well the laws will protect consumers remains to be seen. Reports to the California Department of Public Health's Safe Cosmetics Program do show a tenfold drop in products containing formaldehyde from 2009 to 2022.
"In the very near short term, tomorrow, I think consumers should do the best they can to read product labels," Dodson said. "In the longer term, I think there has to be a regulatory solution. It has to come down to ingredient bans, likely at the state level."
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