Popular Dry Shampoos Found to Have Cancer-Causing Chemical

Top-selling dry shampoos including Not Your Mother’s and Church & Dwight Co.’s Batiste contain high levels of benzene, the cancer-causing chemical that led Unilever to yank its product from shelves in October, according to a new independent study.

Valisure, a New Haven, Connecticut-based analytical laboratory, tested 148 batches from 34 brands of spray-on dry shampoo and found that 70% contained benzene. The chemical can cause certain blood cancers, such as leukemia. The company filed a petition Monday with the U.S. Food and Drug Administration seeking to have the products that contain the substance recalled.

The results add to concerns that products sold over the counter in pharmacies and grocery stores across the U.S. could present previously undetected health risks. Over the past year, Valisure has found benzene in popular spray sunscreens, antiperspirants, and hand sanitizers. Stores have pulled the products from shelves, while regulators and manufacturers are looking more closely at whether impurities are slipping by unnoticed in a complex supply chain.

Read More: The Safest Sunscreens to Buy—and Which Ingredients to Avoid

The highest benzene levels among the dry shampoos were found in a popular brand called Not Your Mother’s, which touts its “clean, quality ingredients.” Other brands found to have elevated benzene included Batiste, Sun Bum, and John Paul Mitchell Systems. Valisure’s petition didn’t include dry shampoos already recalled for elevated benzene, such as Dove, Suave and Bed Head, all from Unilever, as well as Procter & Gamble Co.’s Pantene and Herbal Essences. The benzene levels Valisure found in some of the dry shampoos—used to freshen up hair between washes—are significantly higher than any personal-care products the lab has tested before, the study showed.

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When asked if Batiste had been tested for benzene, a spokesperson for Church & Dwight said the company had previously confirmed with its ingredient suppliers that their products didn’t contain the chemical and said it would evaluate Valisure’s petition. Not Your Mother’s, Sun Bum, and John Paul Mitchell Systems didn’t immediately respond to requests for comment.

Valisure brings in income by partnerships it has with businesses to check the quality of certain products, such as a deal it has with Gojo Industries Inc., the maker of Purell hand sanitizer. It also has investors, including Realist Ventures, which is also based in Connecticut.

Top sellers

Batiste, Not Your Mother’s and Dove are the top selling dry shampoo brands in the U.S., with Batiste making up 44% of the $309 million in sales in the year ending July 10 amongst the top 10 brands, according to IRI, a Chicago-based market research firm. Dry shampoo sales were up 22% from a year earlier, IRI said.

Church & Dwight Chief Executive Officer Matt Farrell told investors on an earnings call Oct. 28 that Batiste use was up 37% in the third quarter from a year earlier, giving the company a 46% market share. Chief Financial Officer Rick Dierker added: “Batiste is growing like crazy. It’s doing fantastic, we can’t meet all the demand, consumption is up dramatically.”

A spray from one can of Not Your Mother’s Beach Babe dry shampoo contained 158 parts per million of benzene, according to Valisure’s findings. In previous studies, the lab found sunscreens with up to 6 parts per million, hand sanitizers with 16 parts per million and antiperspirants with 18. A can of Batiste Bare Dry Shampoo contained 15 parts per million of benzene in one spray. The Environmental Protection Agency has said inhaling benzene at levels of 0.4 parts per billion (.0004 parts per million) chronically over a lifetime could result in one additional cancer per 100,000 people, a measure of risk the FDA also uses.

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“Dry shampoo is not a product you use one time and are done with it,” said David Light, CEO of Valisure. “A lot of people use it once a day, or a few times a week.”

The high numbers call into question statements like the one Unilever made when it recalled Dove, Tresemme, Suave, Bed Head, and Rockaholic dry shampoos on Oct. 18, stating that, “Based on an independent health hazard evaluation, daily exposure to benzene in the recalled products at the levels detected in testing would not be expected to cause adverse health consequences.” Unilever didn’t respond to questions about the levels of benzene found in its products.

“We had seen significant amounts of benzene in Unilever products before they went on recall,” Light said, declining to specify amounts.

P&G was the first to recall dry shampoo in December, pulling Pantene and Herbal Essences versions from shelves. The move came after P&G tested its entire aerosol portfolio following the revelations from Valisure’s previous work. No other major consumer-goods manufacturer has publicly disclosed similar internal testing.

Sunscreens, sanitizers

Valisure has found high benzene levels in spray sunscreens, including versions of Johnson & Johnson’s Neutrogena products; aerosol antiperspirants such as Procter & Gamble’s Secret and Old Spice brands; and some hand sanitizers that were introduced to the market at the start of the coronavirus pandemic in 2020.

The supply chains that bring consumers their grooming products are complex, globe-spanning endeavors, making it difficult to determine precisely where the toxins are introduced.

The problems potentially go back “all the way back to a raw material being contaminated and making it thorough the entire global supply chain, through all the various hands it has to touch, and all the various quality check points that are supposed to be there,” Light said. After all that, “it’s still ending up on the shelf in a customer’s hands, in their homes, with such alarmingly high levels of contamination. That’s very concerning.”

Some companies have pointed to propellants as the problem. Spray personal-care products, including dry shampoos, often contain propellants like propane and butane that are petroleum distillates made by refining crude oil. Benzene is a known contaminant of petroleum products. The propane and butane used in personal-care products are supposed to be purified so that no benzene is present. The FDA has confirmed propellants are a potential source of benzene contamination.

On July 29, Edgewell Personal Care Co. recalled its aerosol Banana Boat Hair & Scalp sunscreen because of benzene contamination. The company said the “unexpected levels of benzene came from the propellant that sprays the product out of the can.”

The FDA has asked companies that make drug products at high risk of being contaminated with benzene, like sunscreen, to test for the toxin.

Dry shampoo is a cosmetic, which the FDA regulates, but not nearly as stringently as it does drugs.

No limits

While the FDA hasn’t set benzene limits for cosmetics, it does say the products shouldn’t contain “any poisonous or deleterious substance.” In drug applications, the FDA allows levels of 2 parts per million of benzene if “use is unavoidable in order to produce a drug product with a significant therapeutic advance.”

Valisure has asked the FDA to clarify that there isn’t an acceptable level of benzene in cosmetic products and to develop guidelines for benzene testing in cosmetics.

Valisure’s analysis found extreme variation in sprays, even from the same can, “suggesting inconsistent product composition and/or aerosolization in some products,” the lab said in the petition. While Not Your Mother’s Clean Freak dry shampoo contained 143 parts per million of benzene in the first spray, the fourth spray contained 93 parts per million. Valisure’s findings, including a list of contaminated dry shampoos, can be found in the petition it filed with the FDA.

The contamination could be even higher than those findings, an expanded study showed.

Valisure has been testing for benzene in personal-care products for some time, but with its dry-shampoo probe, the researchers took a deeper approach. The lab partnered with Syft Technologies, a company that designs and sells trace gas analysis equipment, to conduct direct air-measurement tests, which can more precisely capture benzene levels. Syft is headquartered in New Zealand, with an office in Pittsburgh.

When Valisure tests a product, it uses a standard procedure that requires putting a sample into a vial. This means some chemicals may escape before they’re measured. Syft uses a method that detects chemical levels in the air, including whatever is sprayed from an aerosol can. Using Syft’s data, Valisure determined it’s possible the actual benzene levels in spray-on dry shampoo could be 10 times to 50 times higher than what standard testing reveals.

For example, Syft found benzene levels of 1,600 parts per billion—4,000 times higher than the EPA’s guidance—in the initial cloud of a 10-second spray of Not Your Mother’s dry shampoo. Longer-term exposure showed about 36 parts per billion, with Syft taking measurements in a 550 cubic foot space over 15 minutes. Using that data, Valisure calculated the benzene concentration in the Not Your Mother’s can totaled 340 parts per million, or 170 times the FDA’s limit for drugs.

Data based on Syft’s findings likely more closely mimic real-world conditions. “This is particularly dangerous,” Light said.

—With assistance from Jonathan Roeder.