Mapping radiation from the external and internal sources in Belarus after the Chernobyl disaster: Implications for epidemiological analysis

The explosion at the Chernobyl nuclear power plant in northern Ukraine in April, 1986, was one of the most significant in human history in terms of its impacts on the human population. The explosion caused the release of large quantities of radioisotopes, probably much greater than in the atomic explosion at Hiroshima. Belarus was the Soviet republic most affected by fallout from Chernobyl. Two thirds of all released radionuclides were dispersed on the territory of Belarus. ^ The purpose of this dissertation is to construct and analyze maps of radiation from external and internal sources associated with the Chernobyl disaster in Belarus. The created maps were based on measurements of ground contamination and food contamination taken at 3,326 settlements in the republic in 1991 and 1992. These measurements were converted to an Annual Effective Equivalent Dose (AEED). Unlike the published map of contamination, that was based only on ground contamination by cesium, the maps created in the dissertation show AEED from external (ground) and internal (food) sources. A difference map reveals regions of the country where radiation exposure from internal sources exceeded exposure from external sources. The southern regions of Brest oblast were more affected by Chernobyl when radiation from internal sources is taken into account than it would appear from the published map of contamination. ^ The maps created in this dissertation will help support investigation of human health effects associated with the exposure to environmental hazards as radiation. In addition, the maps and findings of the dissertation might help to develop and evaluate strategies to prevent human exposure to radiation in affected areas of Belarus. Furthermore, the maps might assist epidemiologists to conduct ecological studies and research activities in cooperation with federal, local, and international authorities and health officials.