Radiation effects in lymphocytes of children living in a Chernobyl contaminated region of Belarus.

Purpose : To investigate cytogenetic and mutational eUects in lymphocytes from individuals chronically exposed to radiation from the Chernobyl catastrophe. Materials and methods : Nine years after the Chernobyl accident (1986), peripheral blood lymphocytes from 20 Kalinkovichi children (age 10-15) and 10 Minsk children (age 10-17) were analysed for genetic damage by several assays. Radiation damage in exposed children was investigated in descendants of progenitor cells that were irradiated during a short period immediately after the accident. In the time-span between the accident and blood sampling the cells were also irradiated chronically by internal radiation originating from ingested radionuclides and, to a smaller extent, by external radiation from radionuclides. The parameters measured in whole blood smears were the frequency of micronucleated mononucleated lymphocytes and binucleated lymphocytes with nucleoplasmic bridges and associated micronuclei. Cultures of cytokinesis-blocked lymphocytes were ...