The mechanism of the action of ionizing radiation on the occurence of local changes in cell biological structures under space flight conditions

In space flights the biological objects are exposed to fields of different nature. Of all space flight factors we concentrated our attention on ionizing radiations the action of which was studied in experiments with bacteriophage T4B and with biological structures of the eye. In experiments with bacteriophages their viability and the mutagenic effect under the action of andronic radiation were studied. The effects of local action an phage particles expressed as an induction of deletions and a decrease in viability rate were revealed. We also present the biophysical mechanisms of occurrence of flashes in the eyes of cosmonauts during space flights. The well known hypotheses (Pazio G.G. et al., 1970; Charman W.N. et al, 1971) are based on the occurrence of Cherenkov radiation when a charged particle passes through the eye vitreous body and on a direct action of ionizing particles on the retina. A microdosimetric model was developed (Dmitrievskiy et al., 1982) to calculate the probability of a flash mechanisms. The calculate probability by the mechanism of direct action turned out to coincide with the experimental one and to be 3-4 orders of magnitude less by the mechanism of Cherenkov radiation. However, the experiments on an accelerator (Arodzero et al., 1987) showed that the contributions of the two mechanisms are roughly equal. This disagreement was eliminated due to taking into consideration the polarization of Cherenkov radiation and a highly efficient action of polarized light (established by us earlier) which is 103 - 104 times greater in the region of low intensities than the action of polarized light (Dmitrievskiy I.M., 1985). One more paradox- an increase of two orders of magnitude of visual acuity in cosmonauts watching in some cases terrestrial objects with the naked eye.