Acne treatments have joined the list of common consumer products – like hand sanitisers, sunscreens and dry shampoos – that contain high levels of benzene, previously linked to cancer, with some tested products containing nine times the permitted amount of the chemical.
In a petition filed with the US Food & Drug Administration last week, an independent laboratory said acne products from brands that include Clinique and Proactiv, have elevated levels of the carcinogen. The lab asked the FDA to recall the treatments – all of which contain the active ingredient benzoyl peroxide – while regulators investigate, TIME reports.
Benzene is a natural component of gasoline and tobacco smoke and in high amounts, can cause leukaemia. Over the past three years it’s been detected in several popular products and raised questions about the FDA’s oversight of the industry.
Companies like Johnson & Johnson, Unilever and Procter & Gamble, have all recalled products.
Valisure, the laboratory that filed last Tuesday’s petition and uncovered the previous risks, has positioned itself as a gatekeeper for consumers. Valisure gained prominence conducting product research and has deals with large healthcare systems, including the US Department of Defence, to test drugs used by their members and weed out substandard treatments.
The FDA said the agency would verify whether Valisure’s data was accurate before acting on the petition.
For its acne research, Valisure tested 66 benzoyl peroxide products, including creams, lotions, gels and washes available either over the counter or via prescription. While FDA guidelines allow up to two parts per million of benzene, Valisure found up to nine times that amount in some treatments.
Those levels jumped significantly when the products were tested at higher temperatures designed to replicate how they might break down over time, for example if stored in a medicine cabinet in a steamy bathroom.
Proactiv’s 2.5% benzoyl peroxide cream, manufactured by Taro Pharmaceutical Industries, contained as much as 1 761 parts per million of benzene during Valisure’s stability testing, while a similar cream from Target reached 1 598 parts per million and a treatment from Estee Lauder’s Clinique hit 401 parts per million.
A 10% benzoyl peroxide cream from Reckitt Benckiser Group’s Clearasil initially tested just at the FDA limit, but jumped to 308 parts per million of benzene after being exposed to high temperatures for more than two weeks.
“Reckitt is confident that all Clearasil products, when used and stored as directed on their labels, are safe,” the company said. It didn’t answer questions about whether it had tested its acne cream for benzene.
Representatives for Taro Pharmaceuticals and Estee Lauder didn’t respond to requests for comment.
Acne is the most common skin condition in the US and affects as many as 50m people annually. The numbers are even higher among teenagers and young adults: about 85% of those between 12 and 24 have some form of the condition.
Sales of over-the-counter US acne treatments totalled $1bn last year, almost double the $593m in sales in 2019.
Benzoyl peroxide is one of its top recommendations for treating acne topically.
Valisure President David Light said the contamination happens because benzoyl peroxide can break down and form benzene.
“This has been well known for a long time,” he said. “All that was needed was for someone to check on it.”
Light is listed as an inventor on a patent filed last year for a method to prevent benzoyl peroxide from breaking down into benzene in drug products. The lab tested other kinds of acne products with different ingredients, mainly salicylic acid, and did not find elevated benzene levels in those.
Valisure’s most high-profile investigation was into heartburn drug Zantac, which the FDA pulled from the market along with generic versions in 2020, months after the lab discovered the drug’s active ingredient – ranitidine – could form a probable carcinogen called NDMA.
The FDA has questioned Valisure’s testing methods in the past. Specifically, the agency has said the independent lab should follow the same process that drug manufacturers use, which tends to be costlier than the way that Valisure tests.
Valisure stands behind its testing methods, citing its certification from the International Organisation for Standardisation, which sets testing guidelines for all kinds of products, including drugs.
It said the results from its acne treatment research were similar to its investigation into those ranitidine products.
“The benzene we found in sunscreens and other consumer products were impurities that came from contaminated ingredients, however, the benzene in benzoyl peroxide products is coming from the benzoyl peroxide itself,” Light said.
In 2022, after Valisure’s previous benzene findings, the FDA warned companies that they should assess the risk of the chemical forming in their own products. The agency doesn’t regularly test products it oversees.
Valisure’s testing also examined benzene in the air surrounding acne treatments and found that even an unopened Proactiv product leaked high levels when kept at 40 degrees C – the temperature of a hot shower – for almost 17 hours.
The Environmental Protection Agency has said inhaling benzene at levels of 0.4 parts per billion chronically over a lifetime could result in one additional cancer per 100 000 people, a measure of risk the FDA also uses.
See more from MedicalBrief archives:
Toxic levels of benzene found in dry shampoo – US group wants recall
Cheap BP drug could treat acne – Southampton study
Doctors now favouring combination therapies to treat acne