oxybenzone

Oxybenzone, also known as benzophenone-3, is an organic ultraviolet (UV) filter used in sunscreens and cosmetics to absorb ultraviolet radiation, providing broad-spectrum protection against UVA and UVB rays. It is typically oil-soluble and is often formulated with other filters in various sunscreen products, including lotions, creams, and sprays.

As a UV filter, oxybenzone functions by absorbing solar radiation and converting it to a small amount of heat, helping to prevent skin damage from sun exposure. It is commonly used in cosmetic products designed for sun protection and is frequently combined with other filters to achieve broader coverage across the UV spectrum.

Safety and health considerations include the potential for skin irritation or an allergic reaction in some individuals. Some laboratory and epidemiological studies have reported weak estrogenic activity in certain assays and detectable levels of oxybenzone in human tissues after topical use, though regulatory assessments generally consider its safety within approved concentrations. The compound can be absorbed through the skin and has been detected in urine, blood, and breast milk in some studies.

Environmental and regulatory aspects have drew attention due to detections of oxybenzone in aquatic environments and observed effects on marine organisms in laboratory settings. This has led to restrictions or bans in some jurisdictions, with notable examples including Hawaii’s restrictions on sunscreens containing oxybenzone. Regulatory status and permitted concentrations vary by country and region, often within a low-percent range for products.

Alternatives and substitutes include other UV filters such as avobenzone, octocrylene, and octisalate, or mineral filters like zinc oxide and titanium dioxide. Products marketed as reef-safe often avoid certain organic UV filters in favor of mineral options.