An action spectrum for 8-MOP induced sunburn cells in mammalian epidermis

The histological change known as individual cell shrinkage necrosis (so-called "sunburn cell' in mammalian epidermis) would seem to be suitable for quantitative morphological studies on the effect of psoralen treatment and near UV irradiation. The number of sunburn cells per unit length of epidermis versus varying doses of narrow waveband UVR, 305-375 nm, has been studied and an action spectrum constructed which has maximal activity at 320-335 nm. The implications of these findings are discussed.