Radiation-hygienic monitoring and assessment of the doses of the public residing on the radioactively contaminated territories of the Tula region

Aim of the study: analysis of the results of the radiation-hygienic monitoring of the territories of the Tula region, contaminated due to the Chernobyl NPP accident; concentration of ¹³⁷Cs and ⁹⁰Sr in the locally produced food products and analysis of the annual effective dose of the public. Materials and methods: the study was performed in the Tula region in 1997-2018. It included the evaluation of the indicators of the radiation safety of more than 50 thousand samples of the main food products, sampled in the areas of the radioactive "Chernobyl" contamination of the region with the simultaneous measurement of the external gamma-radiation dose rate in the stationary control points. Additionally, it included the assessment of the dynamics of concentration of ¹³⁷Cs and ⁹⁰Sr in food products, maximal values of mean annual effective doses of the public and contribution of the collective dose from medical exposure into the structure of the annual collective dose of the public. Results: The study allowed estimating the concentration of ¹³⁷Cs and ⁹⁰Sr in the main local food products. Estimated values of gamma radiation dose rate were stable and laid in the range of normal variations specific to the middle latitudes of the European part of Russia. The values of maximal mean annual effective doses of the public indicate the stable radiation environment and do not exceed 1 mSv. It should be mentioned that the contribution of collective dose from medical exposure into the annual collective dose of the public as well as the values of mean individual effective doses from medical exposure are reducing with the increase in the number of X-ray examinations. Conclusions: The lack of exceedances of the pep-produced foodvels of ¹³⁷Cs and ⁹⁰Sr in the locally produced food products and the reduction of the mean annual effective dose of the public indicates the possibility of the transfer of the settlements affected by the Chernobyl NPP accident into the normal living conditions within the program of the of the transfer of the settlements from the ''Chernobyl'' zone.