Doses of internal irradiation of subjects participating in the liquidation of the Chernobyl accident consequences in April-May 1986

This study was aimed at assessing the doses of internal exposure for liquidators of the Chernobyl accident consequences. Doses of internal irradiation were estimated for two groups of subjects who witnessed the accident. Group 1 included 23 subjects who died in May-June, 1986. Group 2 consisted of 375 subjects divided in 2 subgroup (2-A and 2-B). These were the survivors who were examined using human radiation scintillator (HRS) and in whom gamma-radiating markers of fuel particles were detected in 1986-1988. Recovery of exposure doses for subjects witnessing the Chernobyl accident showed that 1) the mean expected suspended equivalent dose of internal irradiation for group 1 was 600 mSv. By the moment of death no more than 4 % of this value was realized; 2) the mean effective dose of internal irradiation for group 2-A was 130 mSv, the expected mean equivalent dose for the lungs 510 mSv; 3) the mean expected effective dose of internal exposure for group 2-B was 40 mSv, the expected mean equivalent dose for the lungs 120 mSv. The estimates of expected doses of internal exposure of subjects witnessing the accident indicate an appreciable contribution of the sources of internal irradiation of individual organs, and that this contribution should by no means be neglected in analysis and prediction of the medical consequences of the accident. 23 refs.; 8 tabs