Coumarin

Fragrance ingredient, can be a potential allergen for some individuals. Coumarin primarily functions as a fragrance ingredient by volatilizing from the skin surface to stimulate olfactory receptors, imparting a sweet, vanilla-like aroma. While it does not exert direct therapeutic actions on skin physiology, it can interact with epidermal cells upon absorption, which is relevant to its potential to induce sensitization.

Coumarin is a well-known fragrance allergen and is listed among the 26 substances requiring declaration in the EU. It has the potential to induce skin sensitization and allergic contact dermatitis in susceptible individuals. The CIR Expert Panel has not specifically reviewed coumarin, but its safety as a fragrance has been extensively assessed by the SCCS in the EU and IFRA.

Look for products with Typically used at very low concentrations, generally below 0.1%, with specific maximum limits (ranging from 0.002% to 0.06%) depending on the product category and regulatory standards (e.g., IFRA, EU Cosmetics Regulation) due to its sensitizing potential. EU regulations require labeling if concentrations exceed 0.001% in leave-on products or 0.01% in rinse-off products. for clinical efficacy.