[The adaptive reaction of the blood lymphocytes in persons subjected to chronic radiation exposure at low doses].

The changes in the PHA-stimulated human blood lymphocytes of the peoples from Moscow and from polluted after Chernobyl disaster Bryansk region were studied. The decrease in lymphocyte mitotic index in residents from polluted regions was revealed. Moscow population was not distinguished from Bryansk region population by the frequency of cells with micronuclei. There was also no difference in frequency of micronuclei after 1 Gy irradiation of the these populations. The adaptive response (irradiation with a dose of 0.05 Gy followed by 1.0 Gy irradiation 5 hours later) was studied. The decrease in the number of individuals with adaptive response and appearance of the individuals with increased radiosensitivity in the population of polluted regions were observed. There was no such subpopulation among the Moscow residents. So, firstly, low dose chronic irradiation is not an adaptive factor; secondly, the determination of adaptive response can be methodological procedure for the revealing the changes which were induced by low dose chronic irradiation (accompanied by other environment agents).