Hand sanitizers were tainted by benzene. Sunscreens and dry shampoos too. Now acne treatments are joining the list of widely used consumer products found to contain high levels of the chemical linked to cancer.

Acne products from brands including Proactiv, Target Corp.’s Up & Up and Clinique have elevated levels of the carcinogen, an independent testing laboratory said in a petition filed with the US Food and Drug Administration. The lab asked the FDA to recall the affected treatments—all of which contain the active ingredient benzoyl peroxide—while regulators investigate. 

Benzene is a natural component of gasoline and tobacco smoke and can cause leukemia in high amounts, according to the US Centers for Disease Control and Prevention. Over the past three years it’s been detected in several popular products, heightening consumers’ awareness of the potential threats in their bathroom cabinets and raising questions about the FDA’s oversight of the industry. Companies including Johnson & Johnson, Unilever Plc and Procter & Gamble Co. have recalled products.

New Haven, Connecticut-based Valisure LLC, the testing laboratory that filed 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 health-care systems, including Kaiser Permanente and the US Department of Defense, to test drugs used by their members and weed out substandard treatments. The FDA said the agency would work to verify whether Valisure’s data is accurate before acting on the lab’s petition. “The agency will continue to provide updates to the public regarding benzene in drug products, as appropriate,” Jeremy Kahn, a spokesperson for the FDA said in a statement. Companies are required to ensure the safety of their products, he said.

For its acne research, Valisure tested 66 benzoyl peroxide products, including creams, lotions, gels and washes available either over the counter from major retailers or via prescription. While FDA guidelines allow up to 2 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 Ltd., 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 Cos.’s Clinique hit 401 parts per million. 

A 10% benzoyl peroxide cream from Reckitt Benckiser Group Plc’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 in a statement. The safety and quality of products are its top priority, Reckitt said. It didn’t answer questions about whether it had tested its acne cream for benzene. Walgreens Boots Alliance Inc. said it’s reviewing Valisure’s petition. 

“We work with our suppliers to follow FDA regulations and guidelines for Walgreens branded products,” the company said in a statement. 

Representatives for Taro Pharmaceuticals and Estee Lauder didn’t respond to requests for comment. Target declined to comment. Reckitt fell 2% and Unilever dipped 0.4% in London, while Estee Lauder slid 1.3% and Taro tumbled 2.4% at the close in New York.

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 in an interview. “All that was needed was for someone to check on it.”