Benzophenone-3 (2-hydroxy-4-methoxybenzophenone) occurs naturally in some flowering plants. It is commercially synthesized as a sunscreen for use in lotions, conditioners, and cosmetics. It is also used as a UV stabilizer in plastic surface coatings and polymers.Benzophenone-3 is a common ingredient in sun-blocking agents.
People may be exposed through dermal application of sunscreens and cosmetic products.Small amounts of benzophenone-3 can be absorbed through human skin and excreted in the urine, mostly as a glucuronidated conjugate. After dermal application of a 4% lotion over the entire body daily for 5 days, one study found that 1.2-8.7% of the applied benzophenone-3 amount was recovered in the urine (Gonzalez et al., 2006).
Human health effects from benzphenone-3 at low environmental doses or at biomonitored levels from low environmental exposures are unknown.Following dermal application, some cases of photoallergy or allergy to benzophenone-3 have been reported.
