The FDA missed its fifth deadline to propose banning formaldehyde and certain formaldehyde-releasing chemicals from hair-straightening products. The proposed rule was supposed to have been published by December 31, 2025, but the agency has yet to confirm when or whether this official action will be taken, according to a CNN report.

The proposed rule notes that formaldehyde, a colorless, flammable gas, has been linked to sensitization reactions, breathing problems and an increased risk for certain cancers, including myeloid leukemia (which occurs in the blood and bone marrow).

Hair-straightening treatments have also been linked to a higher risk for uterine cancer. In fact, a study found that women who used hair-straightening products more than four times in the previous year were more than twice as likely to be diagnosed with uterine cancer compared with those who did not use such products.

Another study previously published in the American Journal of Epidemiology linked hair relaxers to a slight decrease in a person’s ability to conceive, adding to an increasing body of research that links toxic, endocrine-disrupting chemicals found in beauty products to reproductive health issues.

The first deadline for the proposed rule was set for October 2023, but that was later changed to April 2024, then November 2024, March 2025, July 2025 and finally the the last day of December 2025, said David Andrews, acting chief science officer at the Environmental Working Group, a nonprofit health advocacy group, according to CNN News.

“Every delay directly puts at risk the health of salon workers and consumers, particularly Black women, who are disproportionately exposed to harmful chemicals in personal care products,” Andrews said.

Most Black and Latina women use not only hair straighteners that contain formaldehyde but also many personal care products that include the ubiquitous carcinogen, such as shampoos, body soaps, lotions, eyelash glue and more.

The Food and Drug Administration (FDA) encourages people to read product labels to ensure they do not include formaldehyde, but ingredient listings might not refer to the toxic chemical by its most recognizable name.

A recent study published in Environmental Science & Technology Letters, which was the first to demonstrate that formaldehyde and formaldehyde-release preservatives are used in various skin and hair products beyond hair straighteners and relaxers, confirmed that it can be hard for the average consumer to identify which products contain formaldehyde.

“They have long, weird, funny names, and they typically don’t have the word formaldehyde in them,” said lead study author Robin Dodson, ScD, an exposure scientist at Silent Spring Institute, where the research was conducted.

What’s more, according to an FDA fact sheet, some hair-straightening products that don’t list formaldehyde as an ingredient may contain formalin, which is formaldehyde dissolved in water, or methylene glycol, which may be converted into formaldehyde when heated.

CNN reported that an email it received from an agency spokesperson stated that the FDA’s proposed ban of the chemical continues to be a priority and that the group might adjust the anticipated publication date of this and other proposed rules when appropriate, providing periodic updates to deadlines, which typically occur in the spring and fall.

But the elephant in the room is that there is no formal consequence or penalty the agency incurs for missed deadlines, noted CNN’s report.

“The FDA must act immediately to ban formaldehyde in hair-straightening products,” Andrews told CNN. “After more than a decade of warnings, promises and scientific agreement, the risk to public health is simply too great to wait any longer.”

To take a deeper dive into the background of this as yet unsettled issue, check out this roundup of stories about the presence of formaldehyde in personal care products and the timeline for its proposed banning by the FDA.