Acne Products May Release Benzene Even at Room Temperature, Study Shows

Last week, researchers published a study in the Journal of Investigative Dermatology showing that benzoyl peroxide in acne products like ProActiv and Clearasil can degrade into benzene even at room temperature. This follows a March 2024 study that found high benzene levels in acne products when exposed to heat, although that report faced scrutiny for lacking details on its testing methods.

Valisure Laboratories, which conducts testing for the pharmaceutical industry, sponsored both studies and filed a citizen petition with the Food and Drug Administration (FDA) calling for action on the products.

David Light, co-founder and president of Valisure, told Verywell that the FDA has informed the company that the petition is under review. The FDA did not respond to Verywell’s inquiry about the petition.

The researchers tested over 100 benzoyl peroxide acne products purchased from major retailers in six states and found high benzene levels in several products. For instance, the study reported that Proactiv contained 18 times the benzene level allowed by the FDA, while a CVS brand acne face wash had 13 times the permitted amount.

Benzene appears to form when the acne products are at room temperature, at high heat, or when exposed to UV light, according to the researchers. They added that since these products are frequently used in the long term, they could increase exposure to benzene, and there’s no safe level of exposure to the chemical.

“The potential degradation of benzoyl peroxide into benzene has been a topic of concern in dermatology. Our research demonstrates that BPO products can generate benzene at typical room and store shelf temperatures, while cold storage significantly reduces this formation,” said
Christopher Bunick, MD, PhDa co-author of the study and a faculty member in the department of dermatology and program in translational biomedicine at the Yale University School of Medicine.

Bunick said the study suggests a need to recommend refrigeration of benzoyl peroxide products throughout the supply chain—from manufacturing to patient use—to limit benzene exposure. He also noted that in the second study, 34% of the benzoyl peroxide products off the store shelf had benzene above the FDA’s conditional limit of 2 ppm (parts per million).

The possibility of high concentrations of benzene in acne and rosacea products “is an important issue that we should take seriously,” said John Barbieri, MD, director of the Advanced Acne Therapeutics Clinic at Brigham and Women’s’ Hospital.

“However, we also must not overreact,” Barbieri added. “Benzoyl peroxide is a foundational acne treatment without any clear alternative [and] there is currently no evidence to support that routine use of benzoyl peroxide-containing products for acne is associated with a meaningful risk of benzene in the blood.”

Barbieri said potential benzene exposure from acne products needs to be considered in the context of other exposures in daily life. He added that the skin absorption of benzene may be minimal, and it’s unclear how much benzene aerosolizes with routine use, especially in face cleansers that are not meant to stay on the skin.

“If people are concerned, it would be better to use a benzoyl peroxide wash, rather than a ‘leave on’ product,” Barbieri said, adding that FDA input and further testing by independent researchers is needed.

In the meantime, Barbieri said it might be best to avoid Proactive and CVS Health acne products as these were the most concerning brands based on the new Valisure report.