Identification of 1-adenine DNA adducts in workers occupationally exposed to styrene

Styrene is an extensively used industrial chemical that has been classified as a possible human carcinogen. The possible carcinogenicity may be relate d to the covalent DNA binding properties of styrene 7,8-oxide, a major meta bolite of styrene. We have developed a sensitive and a highly specific phos phorus-32--postlabeling method for the determination of 1-styrene 7,8-oxide -adenine DNA adducts. These adducts were analyzed in white blood cells from workers exposed to styrene at mean level of 76.2 mg/m(3). Three of nine ex posed workers showed adducts above the detection limit; the mean was 0.79 /- 0.14 1-styrene 7,8-oxide-adenine DNA adducts/10(9) nucleotides. None of the 11 control cells showed adducts above the detection limit, which was 0. 4 adducts/10(9) nucleotides. The results show a potential of I-adenine DNA adducts for predicting risks in the workers exposed to styrene.