Further Details
Under high temperatures, or over a long period, BP can decompose to benzene, a colorless, flammable liquid with a sweet odor. Benzene is formed from natural processes such as forest fires and volcanoes, according to the American Cancer Society, and is found in the air, cigarette smoke, some foods (at low levels), and contaminated drinking water. It’s one of the 20 widely used chemicals involved in making plastics, resins, detergents, and pesticides, among other products.
In the study evaluating blood levels, the researchers matched 14 people who used BP products currently with 65 controls who did not. Five (36%) of those using the products had detectable blood levels; 21 (32%) of those who did not use them did. There was no association between BP exposure and detectable blood benzene levels (odds ratio, 1.12; P = .80).
In the larger study, the researchers used the TriNetX US Collaborative Network database, comparing more than 27,000 patients treated with BP products for acne with more than 27,000 patients aged 12-40 years who had a diagnosis of nevus or seborrheic keratosis with no exposure to prescribed BP or any diagnosis of acne, hidradenitis suppurativa, or rosacea. The researchers looked at the database over the subsequent 10 years to determine the risk for either blood cancers or internal malignancies.
Compared with patients diagnosed with nevus or seborrheic keratosis, those with acne treated with BP had no significant difference in the risk for lymphoma (hazard ratio [HR], 1.00), leukemia (HR, 0.91), any lymphoma or leukemia (HR, 1.04), and internal malignancies (HR, 0.93).
The findings suggest no increased risk for malignancy, the researchers said, although they acknowledged study limitations, such as possible misclassification of BP exposure due to OTC availability and other issues.
Value of BP Treatments
BP is the “go-to” acne treatment, as Dr. Barbieri pointed out. “It’s probably the number one treatment for acne,” and there’s no substitute for it and it’s one of the most effective topical acne treatments, he noted.
Despite the reassuring findings, Dr. Barbieri repeated advice he gave soon after the Valisure report was released. Use common sense and don’t store BP-containing products in hot cars or other hot environments. In warmer climates, refrigeration could be considered, he said. Discard old products. Manufacturers should use cold-chain storage from the manufacturing site to retail or pharmacy sale sites, he added.
FDA and Citizen Petition Status
Asked about the status of the petition from Valisure, an FDA spokesperson said: “The FDA does not comment on the status of pending petitions.”
Dr. Barbieri and Dr. Lim had no relevant disclosures. There were no funding sources for either of the two studies.
A version of this article first appeared on Medscape.com.