Dry shampoo has joined the growing list of cosmetic and hygiene products that contain benzene, a known human carcinogen, according to an .
Of 148 batches of dry shampoo spray from 34 different companies, 70% contained quantifiable levels of benzene. Some products contained up to 170 times the FDA-imposed benzene limit of 2 parts per million (ppm), Valisure found.
For example, Not Your Mother's dry shampoo had a benzene concentration of up to 340 ppm. Other brands whose products contained benzene levels above the FDA limit included Paul Mitchell, Sun Bum, Batiste, Sebastian, and Redken, among others.
Valisure filed a with the FDA Monday, requesting a recall of contaminated dry shampoo products. They also asked the agency to redefine and clarify benzene limits in cosmetics and other regulated products, noting that their findings represent the highest and most broadly detected levels of benzene that it has found in a consumer product to date.
"The detection of high levels of benzene in dry shampoos should be cause for significant concern since these products are likely used indoors, where benzene may linger and be inhaled for prolonged periods of time," David Light, CEO of Valisure, said in a press release.
"Unfortunately, it's not so surprising that we continue to see benzene in consumer products, especially in aerosol consumer products," Light told 鶹ý. While Valisure has detected benzene in other household products, Light said this assessment makes it much more evident that propellants in aerosol products are a potential source of benzene contamination.
Benzene, which is used primarily as a solvent in chemical and pharmaceutical industries, is known to cause leukemia or other blood disorders in humans. Trace levels of the carcinogen can be found in cigarette smoke, gasoline, glues, adhesives, cleaning products, and paint strippers. It is also a contaminant in the petroleum industry, the press release noted.
Dry shampoos often contain propellants such as butane, isobutane, or propane, which may all be sources of benzene contamination.
Valisure has previously detected unlawful levels of benzene in hand sanitizers, sunscreens, and spray deodorants. The high presence of the cancer-causing agent in these hygiene and cosmetic products is evidence that further industry and regulatory action is needed, Light said.
The company's analysis of dry shampoo products follows a from Unilever, which pulled several dry shampoo products due to elevated levels of benzene, including those from Dove, Nexxus, Suave, Bedhead, and TRESemmé. Valisure did not include any of these voluntarily recalled dry shampoo products in its petition.
For their analysis, Valisure collaborated with Syft Technologies to conduct tests of benzene levels in the air after spraying dry shampoo products, using Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) technology, which may be able to capture more benzene than previously used methods, Light said.
"I think that it is even more concerning that we may be underestimating -- pretty significantly -- the amount of benzene that we're finding," Light noted, adding that the SIFT-MS technology should be rapidly adopted to evaluate consumer spray products.
The FDA has to benzene contamination in recent months, clarifying that they should appropriately test their products for levels above 2 ppm. Light said that further action is needed to clarify the levels found in other consumer and household products.
"It's encouraging that there is progress in this space," he added. "But we still have, I think, quite a ways to go until we really fully address this problem and the risks that come from it."