January 17, 2024

Hair care products used primarily by Black women can contain chemicals that have been linked to a range of health effects, including hormone disruption and certain cancers. Scientists from two NIEHS-funded Environmental Health Sciences (EHS) Core Centers are studying the factors that influence hair product use and how exposure to chemicals in these products, such as phthalates and formaldehyde, may contribute to environmental health disparities among Black women.

Led by Harvard EHS Core Center members Tamarra James-Todd, Ph.D., and Marissa Chan, a team of researchers found that hair products containing harmful chemicals may be more commonly sold in neighborhoods that are low-income or that comprise more people of color compared to affluent, predominantly White neighborhoods. According to the researchers, limited access to safer hair care products may contribute to the disproportionate burden of environmental exposures in communities of color and lower-income neighborhoods.

Research led by Jasmine McDonald, Ph.D., of the Columbia EHS Core Center, revealed that the use of hair oils and hair relaxers during childhood was associated with starting menstruation earlier in life — a risk factor for breast cancer. These products are often marketed to Black women, many of whom begin using the products at an early age.

McDonald noted that people can limit their exposure to these harmful chemicals by switching to safer products.

“If you decided today that you were no longer going to use a phthalate-containing product, within three days we could see a difference in your phthalate exposure. So they're not long-lived chemicals,” she said. “So, the next product you put on your hair, you can choose for it not to have phthalates, you can reduce your exposure. And I think that makes it less scary – that the chemicals don't live in your body forever.”