Radiation-induced effects on bone marrow of bank voles inhabiting the Chornobyl exclusion zone

Abstract

Purpose To investigate the effects of chronic exposure to low-dose radiation on bone marrow hematopoiesis of bank voles inhabiting the radioactively contaminated territory of the Chornobyl exclusion zone. Materials and methods Animals were collected within the highly radioactive area of the so-called Red Forest located close to the destroyed 4th reactor of the Chornobyl Nuclear Power Plant. Radioecological investigations included evaluation of radiocontamination of soil samples by 90Sr and 137Cs, levels of incorporated radionuclides in animals’ bodies and organs, as well as the absorbed dose rates. The study of peripheral blood and bone marrow parameters combined with cytogenetic analysis of bone marrow micronucleated polychromatic erythrocytes and standard metaphase test was carried out. Results The blood system of the exposed animals manifested significant changes in peripheral blood parameters (anaemia and leucocyte formula left shift), ineffective differentiation and maturation of bone marrow cells, particularly relevant to the erythroid and granulocyte pools. Increased yields of bone marrow micronucleated polychromatic erythrocytes and chromosomal aberrations, including dicentrics and Robertsonian fusion-like configurations, were revealed. Conclusions Observed disturbances in the bone marrow and peripheral blood suggest functional instability and inefficient compensatory and recovery reactions of the blood system of the bank voles from the contaminated areas of the Chornobyl exclusion zone. We assume that they are the consequences both of direct radiation exposure and hereditary pathological changes that have formed in a number of generations inhabiting radioactively contaminated areas.