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PHENYLBENZIMIDAZOLE SULFONIC ACID

Description

Phenylbenzimidazole sulfonic acid, also known as ensulizole, is a water-soluble organic compound widely used in sunscreen formulations. This UVB filter effectively absorbs short-wave ultraviolet radiation, providing protection against sunburn and potential DNA damage. Its chemical structure allows it to remain stable when exposed to sunlight, making it a reliable ingredient in photostable sunscreen products.

Unlike many oil-soluble UV filters, phenylbenzimidazole sulfonic acid's water solubility contributes to lighter, less greasy sunscreen textures, which can be particularly beneficial for daily-use products and those designed for oily or acne-prone skin. It is typically used in concentrations up to 4% in the United States and 8% in Europe and Australia.

While primarily known for its UVB protection, recent studies suggest it may offer some UVA protection as well, though to a lesser extent. Phenylbenzimidazole sulfonic acid is generally well-tolerated by most skin types and has a low risk of irritation or allergic reactions. However, like all active sunscreen ingredients, it should be used as part of a comprehensive sun protection strategy that includes other UV filters, antioxidants, and protective clothing.