A comparison of 32P-postlabelling and immunological methods to examine human lung DNA for benzo[a]pyrene adducts

Human lung DNA isolated from surgical specimens has been examined for the presence of polycyclic aromatic hydrocarbon-DNA adducts using both 32P-postlabelling and immunological methods. Of 12 samples examined to date, five had detectable amounts of benzo[a]pyrene diol epoxide-DNA adducts (BPDE-DNA) as determined by the enzyme-linked immunosorbent assay (ELISA), after immunoaffinity concentration. Values ranged from 3.5 to 11.5 fmol/mg DNA. When the same group of samples was analysed using the 32P-postlabelling technique, adducts could be detected in all the samples examined. There was generally not a good correspondence between the two methods. The number of adducts measured by 32P-postlabelling ranged from 1-100 per 10(8) nucleotides, which is some two orders of magnitude higher than with the immunological method, indicating that the BPDE-DNA adduct is probably not the major adduct present in these samples.