The time-effect relationship for chromatid type aberrations, chromosome type fragments, hyperploidy and polyploidy levels in peripheral blood lymphocytes were investigated in inhabitants of t. Pripiat’ and nearby villages, who were departured from the Chernobyl NPP 30-km exclusive zone during first days after the Chernobyl catastrophe. The time-course changes of the mentioned cytogenetic indices in evacuees were displayed as a gradual decline of chromosomal rearrangements and genome abnormality frequencies from the statistically elevated level in the first 1-2 years after the accident to the subcontrol meanings at the end of the 14-years observation period. In early terms after exposure the frequency of chromatid exchanges in adult men and the polyploidy level in women aged 23-35 years were sufficiently increased comparing with other evacuee subgroups. Some peculiarities of the fragment aberration frequency dynamics were shown for persons with different terms of the departure from the Chernobyl zone. The role of the combination of mutagenic factors acted in the accidental situation at Chernobyl for inducing the elevated level of cytogenetic damage in evacuees is discussed.
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