Ionizing radiation effects on the human organism

The effects of ionizing radiation on the human organism at the molecular and cellular levels are summed up. The early and delayed damage to man caused by irradiation are characterized. In this sense attention is devoted to the acute radiation syndrome, early local effects, malignant growths, genetic changes and the irradiation of the foetus in the mother's womb. Discussed is general biological knowledge in relation to the criteria and principles of health protection. The aim of radiation protection is to regulate the irradiation of people in such a manner as to totally exclude nonstochastic effects, i.e., the effects characterized by the existence of a threshold dose. The principle of all measures taken to reduce the population dose is to reduce the probability of delayed stochastic effects. (Z.M.)