INVESTIGATION OF BENZENE DNA ADDUCTS AND THEIR DETECTION IN HUMAN BONE-MARROW

We have examined DNA adduct formation in HL-60 cells and human bone ma rrow treated with either hydroquinone or p-benzoquinone and have found that these treatments produce the same DNA adduct in both cell types. The DNA adduct level from these treatments varied from 0.05 to 7.5 ad ducts per 10(7) nucleotides as a function of treatment time and concen tration for both compounds. Reaction of calf thymus DNA with p-benzoqu inone produced three adducts as detected by P-32-postlabeling. These a dducts have been identified as oxy)-3,N-benzetheno-2'-deoxycytidine-3' -phosphate; y)-1,N6-benzetheno-2'-deoxyadenosine-3;-phosphate; and y)- 1,N2-benzetheno-2'-deoxyguanosine-3'-phosphate. The DNA adduct formed in HL-60 cells did not correspond to any of the principal adducts form ed in DNA reacted with p-benzoquinone, suggesting that cellular enviro nment modifies DNA adduct production by p-benzoquinone. These studies demonstrate that DNA adduct formation occurs in human bone marrow trea ted with benzene metabolites and suggest that P1-enhanced P-32-postlab eling may be used to detect DNA adducts resulting from benzene exposur e.