Polycyclic　aromatic　hydrocarbons　(PAHs),which　constitute　a　major　class　of　environmental　pollu　tants　are　posing　a　threat　to　human　health.　Benzopyrene,an　index　of　PAH　levels　omnipresent　in　the　everyday　environment　,becomes　toxic　only　when　being　metabolically　and/or　photo-activated,i.　e.　,in　the　pres　ence　of　UV　light.　Free　radicals　such　as　superoxide　anions　(＇＇O2),hydrogen　peroxide　(H2O2),hydroxyl　radicals　(＇＇OH)　and　singlet　oxygen　(1O2)　are　involved　in　carcinogenesis.　Wei　CE　etc[1]　studied　the　effects　of　different　scavengers　of　active　oxygen　species　(superoxide　dismutase,catalase,mannitol　and　dimethyfu　ran)　on　promoting　B[a]P　mutagenicity.　Bryla　P　ete[2]　investigated　the　roles　of　several　ROS　scavengers　in　the　oxidation　and　binding　of　B[a]P　to　calf　thymus　DNA　using　the　32p-postlabeling　assay.