The effect of topical L-selenomethionine on minimal erythema dose of ultraviolet irradiation in humans

The purpose of this study was to determine whether topical L-selenomethionine reduces the degree of acute damage to the skin (i.e., sunburn) induced by ultraviolet (UV) irradiation in humans. Eight women volunteers were treated for 2 weeks first with lotion vehicle then with topical L-selenomethionine for two weeks at each of three concentrations (0.002%, 0.02%, and 0.05%). At the end of each 2-week treatment period, the minimal erythema dose (MED) of UV irradiation was measured using a Multiport Solar Ultraviolet Simulator. It was found that topical L-selenomethionine was effective in protecting against acute UV damage to the skin. A response curve demonstrated that increasing concentrations of topical L-selenomethionine gave increasing MED, with a plateau of maximal protection attained at a concentration between 0.02% and 0.05%. Although previous studies in rats and mice demonstrated percutaneous absorption of selenium after application of L-selenomethionine, in the concentrations used here, the topical L-selenomethionine did not result in increased levels of selenium in the blood plasma of the patients tested.