Investigators have determined that a substantial portion of topical benzoyl peroxide (BPO) acne and rosacea treatments currently on the market are unstable and contain unacceptably high levels of benzene, a known human carcinogen. Degradation of these products and formation of benzene appear to occur when sitting on shelves at room temperature, at elevated temperatures, and when exposed to ultraviolet (UV) levels representative of sunlight. Drug stabilization techniques like encapsulation do not appear to prevent the formation of benzene in BPO drug products.
Groundbreaking research in the Journal of Investigative Dermatology , published by Elsevier, details the findings of this study. The study also showed that in addition to elevated temperatures expected during use and transportation, exposure to UV light at outdoor levels is another concerning mechanism through which BPO drug products degrade into benzene, and one that appears to occur more rapidly than heated storage and transportation conditions. These products are frequently used by consumers over extended periods of time, thereby likely increasing their exposure to benzene; there is no safe level or duration of exposure to benzene.
Co-investigator Christopher G. Bunick, MD, PhD, Department of Dermatology and Program in Translational Biomedicine, Yale University School of Medicine, New Haven, CT, explains, "The potential degradation of BPO into benzene has been a topic of concern in dermatology. Our research demonstrat.