Papers include: Chernobyl and Human Health. A radiation and epidemiological analysis of the aftereffects of the Chernobyl accident as based on the data of the Russian state medical dosimetric registry. Cytogenic effects of the action of ionizing radiations of human populations. Assessment of genetic risk from exposure of human populations to radiation. Immunological disturbances in victims of Chernobyl accident: Aftereffects and an analysis of their nature. Mechanisms of biological action of low-dose irradiation. Damage of the thyroid in the period of the Chernobyl catastrophe: possible consequences. Dynamics of state of health for children's population of Belarus under present-day environmental conditions. Violation of adaptability as a result of Chernobyl breakdown.