CAROTENOIDS QUENCH EVOLUTION OF EXCITED SPECIES IN EPIDERMIS EXPOSED TO UV‐B (290‐320 nm) LIGHT

Reactions involving singlet oxygen and other free radicals have been identified in epidermis containing either exogenous or endogenous photosensitizers. soaked in a singlet oxygen/free radical trap, and then exposed to visible or UV‐A (320‐400 nm) light. Such reactions can be quenched by the presence of the carotenoid pigments β‐carotene and canthaxanthin which accumulate in epidermis after oral administration. We report here that the carotenoid pigments β‐carotene. canthaxanthin and phytoene accumulating in epidermis can also quench to some degree those photochemical reactions involving singlet oxygen and free radicals that occur when epidermis is exposed to the sunburn spectrum of light (UV‐B. 290–320 nm).