Use of the alkaline comet assay to monitor DNA damage in technicians exposed to low-dose radiation

The exposure of human beings to ionizing radiation is still of great concer n in occupational and environmental medicine, and the wide-spread use of ra diotherapy in the treatment of cancer has led to anxiety about the possible hazards to staff who are at risk of such occupational exposure. In. this s tudy, DNA damage in the peripheral lymphocytes of 30 technicians employed i n radiation oncology departments for at least 1 year were examined by the a lkaline single-cell gel electrophoresis "comet" technique, The results were compared with those of 30 controls with comparable age, sex, and smoking h abits who were not working in radiation oncology or chemotherapy services. The DNA damage observed in the lymphocytes of the technicians was significa ntly higher than that in the controls (P < 0.001), Cigarette smoking was al so related to increases in DNA damage, and a significant association was fo und between the duration of occupational exposure to low-dose ionizing radi ation and the DNA damage.