It has long been known that benzoyl peroxide (BPO) will break down into benzene at temperatures above 50°C (122°F). Recent research has raised new concerns about topical benzoyl peroxide products used to treat acne and rosacea. Several studies, including one published in The Journal of Investigative Dermatology, have shown that products containing benzoyl peroxide can degrade into benzene more easily than previously thought, even under conditions like room temperature storage or exposure to UV light.
In addition, researchers are finding traces of benzene in personal care products not as a deliberate ingredient but as an unintentional contaminant introduced during the manufacturing process.
2. What is benzene and what do we know about how it affects the body?
Benzene is a colorless, highly flammable liquid with a sweet odor, classified as an aromatic hydrocarbon. It’s naturally found in crude oil and is a major component in the production of various chemicals, such as plastics, resins, and synthetic fibers.
Breathing in high levels of benzene can cause dizziness, headaches, drowsiness, confusion, and even unconsciousness in extreme cases. Direct skin exposure to benzene can cause redness, irritation, and blistering. Consuming benzene, though less common, can lead to stomach irritation, dizziness, convulsions, and, in severe cases, death.
Prolonged exposure to benzene, even at low levels, can lead to chronic health conditions. Benzene is classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC), meaning there is sufficient evidence linking it to cancer in humans.
3. Where else has benzene been found recently?
Benzene has been found in personal care products across various categories, often as a contaminant or due to degradation of benzoyl peroxide. Some of the most notable product types in which benzene has been detected include sunscreens including Neutrogena and Aveeno. This contamination was thought to arise from the manufacturing process rather than benzene being a deliberate ingredient.
Benzene has been detected in aerosol deodorants, including popular brands like Old Spice and Secret. A recall was issued in 2021 by Procter & Gamble after testing found that some of these spray products contained elevated benzene levels.
In late 2022, several dry shampoo brands, including those from Unilever (like Dove, Suave, and Tresemmé), were recalled due to the detection of benzene in aerosol formulations.
4. What can people do to avoid benzene in their favorite products?
To minimize exposure to benzene in personal care products, consumers can take several proactive steps:
• Check product recalls and safety alerts. Regularly monitor safety recalls from regulatory agencies like the U.S. Food and Drug Administration (FDA) and independent labs such as Valisure, which have been instrumental in detecting benzene contamination in products like acne creams, sunscreens, hand sanitizers, and deodorants.
• Choose non-aerosol products. Many of the personal care products found to contain benzene, such as deodorants, dry shampoos, and sunscreens, have been aerosol-based.
• Store products in cool, dry places, away from direct sunlight. Heat and sunlight can accelerate the formation of benzene in certain products.
• Look for independent certifications. Some personal care products are certified by independent organizations, like the Environmental Working Group (EWG), which provides ratings based on the safety of ingredients.
5. What’s next for research on benzene in popular products? Is this likely to cause major changes in what we see on store shelves at some point?
Regulatory bodies like the FDA may introduce stricter guidelines for permissible benzene levels in consumer products or increase monitoring of high-risk categories such as aerosols. The current limit of 2 parts per million (ppm) is under scrutiny, as some experts argue that no amount of benzene exposure is truly safe.
In response, manufacturers are likely to reformulate products to either eliminate the potential for contamination or stabilize ingredients that degrade into benzene. This could involve removing or replacing problematic ingredients, improving the purity of raw materials, or changing packaging to better protect products from heat and UV exposure. Brands may start to emphasize product safety and independent testing as a selling point, responding to increased consumer demand for non-toxic, transparent options.