A new study finds many popular acne products that contain an ingredient called benzoyl peroxide are not shelf stable and may become contaminated with a known carcinogen even when stored at room temperature.
Researchers tested 111 benzoyl peroxide products from major U.S. retailers in six states and found high levels of the chemical benzene.
They say benzoyl peroxide degrades into benzene over time at room temperature, at elevated temperatures and when exposed to ultraviolet rays from sunlight.
Testing also showed cold storage can significantly reduce benzene formation.
One author says, “These findings suggest a need to recommend refrigeration of [benzoyl peroxide] products throughout the supply chain—from manufacturing to patient use—to limit benzene exposure.”
The EPA classifies benzene as a known human carcinogen, and the FDA says it has “unacceptable toxicity.”
Further research is needed to determine how the potential presence of this chemical in these products may impact human cancer risk.
Source: Journal of Investigative Dermatology
Author Affiliations: Yale University School of Medicine, Long Island University, Valisure, LLC
