STATUS AND RESULTS OF RADIATION-HYGIENIC MONITORING OF SETTLEMENTS IN RADIOACTIVELY CONTAMINATED AREAS OF UKRAINE AT...

the aim of the study was to analyze the results of radiationhygienic monitoring of settlements locatedin radioactively contaminated territories (RCT) of Ukraine at the current stage of the Chornobyl accident, as well asthe dynamics of the main factors contributing to population exposure doses, based on our own experimentalresearch conducted in reference settlements during 2012-2024.

The study covered 23 settlements in RCT of Ukraine: 8 settlements of the Ivankiv andPoliske amalgamated territorial communities (ATC) of Kyiv region, 4 settlements of the Starosilska ATC of Sarny district, Rivne region, and 11 settlements of the Narodychi settlement territorial community (STC) of Zhytomyr region.In the postaccident years, these settlements recorded the highest exposure levels, and once every 3 years a comprehensive radiationhygienic monitoring was performed, which included: field WBClaboratory surveys to assessinternal exposure doses; collection of food samples with subsequent analysis for radionuclides 137Cs and 90Sr; measurement of the exposure dose rate (EDR) to study external exposure; and surveys of residents on food consumptionvolumes, both from their own households and purchased in trade networks. Dosimetric, radiochemical, and mathematical methods were applied in the study.

A general further decrease in the levels of internal exposure was recorded in all surveyed settlements ofKyiv, Zhytomyr, and Rivne regions, against the background of unstable seasonal dynamics during the year. Annualeffective doses of population exposure in reference settlements at the current stage of the Chornobyl accident aremainly formed by internal exposure doses, which did not exceed 0.50 mSv·y 1 in 2022 in Kyiv region, 0.67 mSv·y 1 in2023 in Rivne region, and 1.04 mSv·y 1 in 2024 in Zhytomyr region, with the RCT criterion set at 1 mSv·y 1. The mainfactor determining internal exposure dose is incorporated 137Cs, entering the human body primarily through foodproducts such as milk and forest products, especially mushrooms, which traditionally constitute a significant part ofthe diet in the Polissia region.

The existing radiationecological situation in areas exposed to radioactive contamination as a resultof the Chornobyl catastrophe requires continued monitoring of the levels of radioactive contamination in food products, especially those collected in forests, as well as monitoring of population exposure doses.