STUDY OF DOSE FORMATION FOR THE POPULATION IN RADIOACTIVELY CONTAMINATED AREAS OF ZHYTOMYR REGION BASED ON COMPREHENSIVE RADIATION-HYGIENIC MONITORING.

Objective: the research is to determine the main radiation-hygienic factors influencing the formation of radiation doses among the population of radioactively contaminated territories (RCT) in Zhytomyr region in 2024 and to analyze the dynamics of internal radiation doses based on original experimental studies conducted in reference settlements from 2012 to 2024.

Materials And Methods: In 2024, a comprehensive radiation-hygienic monitoring program was conducted in 11 settlements of Narodychi Territorial Community (TC): the Narodychi and the villages of Selets, Bazar, Rudnya Bazarska, Khrystynivka (Zone 2), Motiyki, Zalissya, Davydky, Radcha, Nova Radcha, and Grezlya (Zone 3). The comprehensive radiation-hygienic monitoring included the following activities: mobile WBC monitoring: 817 measurements (562 adults and 255 children); collection and analysis of food samples: 39 milk samples, 61 potato samples, and 57 samples of wild foods, analyzed for radionuclide content, including 137Cs and 90Sr; assessment of external radiation exposure in these settlements; surveys: 194 individuals were surveyed regarding the consumption volumes of locally produced foods from their own households and purchased foods from commercial networks. The study utilized dosimetric, radiochemical, and mathematical methods of analysis.

Results: The dynamics of internal exposure levels indicate a continued decrease in annual doses for residents of reference settlements, showing a 1.3-2.4-fold reduction compared to 2021 results. In 2024, the annual effective doses are primarily formed by internal exposure, not exceeding 1.04 mSv·year-1 in adults and 0.15 mSv·year-1 in children, under the RCT criterion of 1 mSv·year-1. Survey results show that the most consumed food products among residents of the surveyed settlements are dairy and vegetable products from household farms, as well as baked goods and flour-based products from the retail network. The most contaminated products with 137Cs are wild forest products, particularly berries and mushrooms. Milk from household or local farms is the second-largest contributor to internal exposure doses.

Conclusions: The investigation into the formation of internal radiation doses revealed that the primary contributor to internal exposure for residents of the surveyed settlements in the Zhytomyr region remains the intake of 137Cs through forest products and milk.