Components of adaptive response induced by occupational exposure to ionizing radiation. Some approaches to analysis

The article presents results of study of delayed effects of occupational exposure to alpha and gamma radiation on human genome. The group of 23 former Mayak employees at the city of Ozersk was involved in the study. During their work at the enterprise for plutonium processing they had been exposed to internal and external radiation. Average internal alpha radiation dose to lungs was 0.12±0.024 Gy, to the bone marrow - 0.045±0.0087 Gy. Average individualized external gamma radiation doses to the bone marrow and to the lungs were 1.6±0.1Gy, 1.8±0.12 Gy, respectively. Impacts of ionizing radiation and alpha particles on frequency of micronuclear cells and the components of adaptive response were assessed. Adaptive potential of lymphocytes correlates with doses in internal and external radiation. Results of the analysis indicate that spontaneous DNA damage to the lymphocytes genome is related to the level of internal rather than external damage to irradiation, of human lungs (r=0.51; p=0.015) and the bone marrow (r=0.47; p=0.026), it depends also on the duration of wok with alpha and gamma emitters (r=0.43; p=0.046). Results of the study may be useful for estimating risk of delayed effects on health status of workers dealing with radionuclides processing.