Oxybenzone (also known as benzophenone-3) is a sunscreen agent that protects primarily from the sun’s UVB rays, and some, but not all, UVA rays. It is part of the benzophenone group of chemicals. Oxybenzone is approved for use in specific concentrations for sunscreens sold in all major countries, including the United States, Canada, member countries of the European Union, Japan, Australia, China, and South Korea. As a group, the benzophenones are used not only for sun protection but also as photostabilizers in cosmetic products (they keep products from turning color or degrading in the presence of sunlight). They have other uses as well, including flavor enhancers in food.
Like many other sunscreen ingredients, oxybenzone has had its share of controversies and scare-tactic stories about the alleged dangers of this sunscreen ingredient abound. The Cosmetic Ingredient Review Board has studied this group of chemicals extensively, including oxybenzone. Their review of published studies, usage data, and the like led them to the following conclusions:
- Benzophenones were practically non-toxic when “chronically administered orally to rats” and benzophenone-3 (oxybenzone) was shown to be non-toxic when applied to animal skin. As a reminder, the manner in which humans use oxybenzone in sunscreen formulas is not the same as chronic oral consumption.
- Trace amounts of oxybenzone can be absorbed into the bloodstream via topical application but is readily metabolized and excreted in the urine. A study published in the July 2008 edition of Environmental Health Perspectives found that human exposure to benzophenone-3 (oxybenzone) was so prevalent during 2003-2004 that it was present in the urine samples of 95% of 2,517 study participants. Given this chemical’s presence in so many products, that’s not too surprising. What remains to be seen (but is suspected to be true) is that the presence of oxybenzone in the urine is not cause for concern. Lots of substances are present in urine; just being present doesn’t make it a health hazard and given its long history of safe use, many experts doubt it will be proven hazardous. Keep in mind that many foods we eat contain substances that, if not for our excretory system, could be harmful to the body.
- As a group, benzophenones were “nonirritating or mildly irritating” when applied to rabbit skin at concentrations of up to 100% and “practically nonirritating” when applied to rabbit eyes. Aside from the issues of animal testing, this is good news for consumers given the significantly lower percentages of benzophenones (including oxybenzone) permitted for use in sunscreens.
- Oxybenzone was shown to be non-phototoxic (doesn’t cause skin reactions in the presence of sunlight) and non-sensitizing when applied to animal skin
- The group concluded that “on the basis of available animal data and clinical human experience” the benzophenones in question, including oxybenzone, “are safe for topical application to humans in the present practices of use and concentration in cosmetics”
- Oxybenzone was not shown to have hormone-disrupting effects when used as directed in permitted concentrations. Research to the contrary has been disproven by the European Union’s Scientific Committee for Cosmetic Products and Non-Food Products Intended for Consumers, which is why oxybenzone is still permitted as a viable sunscreen throughout the European Union. In fact, the EU’s usage level for oxybenzone is higher than what is permitted in the United States (10% vs. 6% maximum). Later research on this topic has either been in-vitro or has focused on controlled doses of benzophenones given to fish, which isn’t representative of how these chemicals are used by people.
- Benzephenone is a substance found in plants that have been shown to actually kill cancer cells. Some benzophenones have been shown to have estrogenic properties and anti-dihydrotestosterone after being fed or injected to rats or applied to rat cells in lab dish, whereas benzophenone itself was shown to have no effect at all. There is research showing it is not linked to estrogenic activity. There is one study that showed it stimulated breast cancer cells in vitro (meaning in a lab dish). But that is vastly different from how oxybenzone is used in sunscreens.
Sources for the information above: Photodermatology, Photoimmunology,and Photomedicine, April 2011, pages 58–67 and August 2008, pages 211–217; Phytotherapy Research, March 2010, pages 379-383; 2007 CIR Compendium, Cosmetic Ingredient Review, 2007, pages 37-38; www.cosmeticinfo.org; http://ec.europa.eu/health/ph_risk/committees/sccp/docshtml/sccp_out145_en.htm; Toxicological Sciences, April 2006, pages 349-361; Skin Pharmacology and Physiology, July-August 2005, pages 170-174; Toxicology and Applied Pharmacology, February 2005, pages 9-17; Toxicology, December 2004, pages 123-130; Archives of Toxicology, December 2002, pages 727-731; http://onlinelibrary.wiley.com/doi/10.1111/j.1600-0781.2011.00557.x/full; and www.aad.org/stories-and-news/news-releases/sunscreens-remain-safe-effective-form-of-sun-protection).