[The state of hemopoiesis under conditions of long-term bone marrow irradiation in residents of the Techa riverside villages].

: The paper presents the results of a 50-year study on the state of hemopoiesis in the Techa riverside residents chronically exposed to radiation in the range from low to intermediate doses. The highest bone marrow doses were attributable to intakes of osteotropic 9OSr with drinking water and local food products. During the period of maximum radiation exposures (1951-1953) exposed residents were manifesting decreased counts of peripheral blood leukocytes (neutrophils and lymphocytes) and thrombocytes. Normal counts of erythrocytes were maintained owing to the effect of sufficient compensatory mechanisms, including accelerated rates of erythrocaryocyte proliferation and maturation. The development of peripheral blood granulocytopenia was influenced by the delay in the differentiation of neutrophilic bone-marrow granulocytes at the myelocyte phase, a marked increase in the frequency of lethal abnormalities in bone-marrow neutrophils, and pathological mitoses. The period of normalization of the blood cell composition was significantly variable for different blood cell series, and was noted to depend on exposure dose rate, extent of the primary hemopoiesis inhibition and specific physiological characteristics of exposed individuals.