DETECTION AND QUANTIFICATION OF 8-HYDROXYDEOXYGUANOSINE ADDUCTS IN PERIPHERAL-BLOOD OF PEOPLE EXPOSED TO IONIZING-RADIATION

Ionizing radiation produces a variety of damaging insults to nucleic acids, including the promutagenic lesion 8-hydroxydeoxyguanosine. In the present study, the 8-hydroxydeoxyguanosine content of peripheral blood leukocyte DNA isolated from individuals exposed to therapeutic doses of ionizing radiation was determined by a HPLC-coupled P-32-postlabeling assay. Peripheral blood leukocyte DNA from individuals irradiated with 18-200 cGy were observed to contain 24.5 times as much 8-hydroxydeoxyguanosine as that from unexposed individuals. These results were confirmed by the use of a HPLC-coupled electrochemical detection system. Thus, human exposure to ionizing radiation significantly increased the circulating leukocyte DNA content of 8-hydroxydeoxyguanosine.