Estimate of DNA Sensitivity in Occupational Exposure to Ionizing Radiation to DNA-Damaging Agent -a Comet Assay

In this study induction of DNA strand breaks in peripheral blood mononuclear cells (PMNCs) of 24 staffs (radiation workers) occupationally work in the site of Atomic Energy Organization of Iran (AEOI) was assessed. The effect of various doses of oxidative damage, Blemycin (BLM) and gamma radiation on the DNA damage and repair in PMNCs were studied by alkaline comet assay and the results was compared with 24 control unexposed volunteer from Tehran which were matched for age, sex and smoking habits. The comets were measured for an average of 100 cells per each case. Bleomycin produced severely damage and reached a saturation point around 20 µg/ml in both groups, but no difference were found in term of induved and repaired A damages with this agent. However, after H2O2 and ג- treatment, a dose-dependent increase of single strand Break (SSB) was observed. The amount of DNA damages induced by H2O2 was found to be the radiation workers at 4 Gy, was found to be higher (p < 0.1).

Keywords:

radiation workers , oxidative damage , g-radiation , bleomycin , comet assay , adaptation