As a result of an accidental outburst of long-lived radionuclides at the nearest zone of the trace, a dose rate of gamma-radiation was several dozen CGy/h and in the open country at some populated areas it was 0.1 CGy/h. The evacuation of 10730 persons permitted a decrease of possible radiation doses 2-24-fold. A follow-up of persons who had been exposed to the highest effective equivalent doses of radiation before the evacuation revealed unstable indices of leukocytes and platelets (however they were within normal variations) in the first 2 years. Morbidity and mortality rates among the adults, the rates of congenital diseases and pediatric mortality did not differ from the control values. The rate of families having children born from persons aged 10 to 30 at the time of the accident did not differ from the similar rates for the USSR; this rate was lower by 5-10% than the control values for persons aged 0 to 9 at that time. Standardized birth rates in the study group (31 x 8,10(-3)) were much higher than in the control group (18 x 4,10(-3)).