[Action of protons with 25 and 50 MeV energies on the chromosomes of human peripheral blood lymphocytes in vitro].

The frequency and type of chromosomal abberations in human lymphocytes induced by 25, 50, 645 MeV protons and 200 kv x-rays were studied. It was shown that the yield of one-hit acentric fragments increased linearly and that of double-break aberrations increased exponentially with the irradiation dose. It was demonstrated that under the influence of radiations with high linear energy transfer the number of paired fragments increased and that of dicentrics and rings decreased. The test of total yield of chromosomal aberrations and their specific types helped to derive coefficients of relative biological effectiveness of the above irradiations. There was a quantitative correlation between the dose and yield of individual aberration types. This suggests that lymphocytes can be used as a biological dosimeter for dose measurement.