title: Absence of psoralen--type phototoxicity from usnic acid, some lichens, and lichen substances.
authors.forename: J C
authors.initials: JC
authors.lastname: Mitchell
mesh_terms: D001572:Benzofurans / Q000633:toxicity*; D017484:Dermatitis, Phototoxic / Q000209:etiology*; D008011:Lichens / Q000737:chemistry*
chemical_list: D001572:Benzofurans; C073339:usnic acid