The prospects of the development of the method for monitoring of occupational exposure to some alkylating agents.

DNA-adduct formation, depurination and imidazole ringopening were followed in vitro using styrene oxide, ethyleneimine and dimethyl sulfate. Depurination was found to be about 50 times faster in nucleosides than in double-stranded DNA. The half-lives of depurination in DNA were 3 times faster for 7-(2-aminoethyl)guanine as compared to 7-methyl- and 7-(2-hydroxy-2-phenylethyl)deoxyguanosine. In neutrally 7-methylguanine was released some 60 times faster than that of guanine and adenine. This apparent discrepancy in depurination between alkylated and intact bases suggests the possibility of developing a sensitive method for monitoring of DNA alkylations formed by electrophillic chemicals, which might be based on labelling of apurinic sites and utilized for in vivo studies as well.