Radiation doses to the population in different periods after the Chernobyl accident

The purpose of the study is to analyze radiation doses to population residing in territories contaminated with radionuclides calculated in different periods after the Chernobyl accident. Temporal changes of radiation doses to residents of the territories with different levels of radioactive contamination and types of soil, as well as the contribution of internal and external radiation doses to integral radiation dose were analyzed. The authors found that the value of internal radiation dose as compared with the external dose in the first years after the accident depended on a type of soil, it was higher (about 55%) in residents of territories with prevailing light type of soil, it decreased with time, at the present time it is about 25%. In the territories with prevailing heavy type of soil the value of internal radiation dose to the residents was lower, it was about 25-30% in 1990 and 5-7% in 2000.