Study finds high levels of cancer-causing chemical in several sunscreen brands

An independent study found that several commonly used brands of sunscreen in the U.S. contain high levels of a chemical known to cause cancer.

Out of nearly 300 different sunscreen products, 27% contained benzene, according to Valisure, an online pharmacy that tests medications and supplements for safety and consistency. 

Valisure said it analyzed 294 unique batches of sunscreen from 69 different companies. Fourteen batches of sunscreen contained between 2.78 and 6.26 parts per million of benzene. 

Currently, the FDA has a conditional restriction on benzene in products set at 2 parts per million. But the agency says "if their use is unavoidable in order to produce a drug product with a significant therapeutic advance, then their levels should be restricted."

In an open letter to the U.S. Food and Drug Administration, Valisure urged the agency to immediately recall batches of sunscreen they say have been contaminated with the harmful chemical. 

"Benzene is known to cause cancer in humans according to the U.S. Centers for Disease Control and Prevention, the U.S. Department of Health and Human Services, the World Health Organization, and other regulatory agencies," Valisure said.

"Valisure is asking for a recall of the contaminated batches and requesting FDA better define limits for benzene contamination in drug and cosmetic products," the pharmacy added. 

Valisure explained that it is important to note that not all sunscreen products contain the cancer-causing chemical and that consumers should seek out uncontaminated products which are available because of the importance of protecting against potentially harmful solar radiation. 

Benzene is a known human carcinogen, linked to leukemia and other cancers of blood cells. The International Agency for Research on Cancer, the World Health Organization’s cancer research arm, notes that that benzene exposure has been linked with acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), multiple myeloma, and non-Hodgkin lymphoma.

The National Institute for Occupational Safety and Health lists benzene exposure routes as "inhalation, skin absorption, ingestion, skin and/or eye contact."

"Benzene is one of the most studied and concerning human carcinogens known to science. Its association with forming blood cancers in humans has been shown in numerous studies at trace levels of parts per million and below. The presence of this known human carcinogen in products widely recommended for the prevention of skin cancer and that are regularly used by adults and children is very troubling," said David Light, Founder and CEO of Valisure.

In March, Valisure detected harmful levels of benzene in dozens of batches of hand sanitizers produced in the U.S. during the onset of the COVID-19 pandemic in an attempt to curb the spread of the disease. 

Out of 260 hand sanitizer products tested, 44 batches (17%) contained benzene, according to Valisure.

During the COVID-19 public health emergency, the FDA allowed an interim limit of 2 parts per million (ppm) for benzene in liquid hand sanitizers in order to help meet high demand.

"Based on our review of available data, we have determined these interim impurity levels can be tolerated for a relatively short period of time, given the emphasis on hand hygiene during the COVID-19 public health emergency and to avoid exacerbating access issues for alcohol-based hand sanitizer," the FDA said in June.

Among the batches of hand sanitizer tested by Valisure, the highest level of benzene detected was 16.1 parts for million, which is over eight times the FDA’s temporary limit.

Valisure provided a list of every batch of hand sanitizer tested in its analysis.