COMPLEX RADIATION AND HYGIENIC MONITORING OF POPULATION ON RADIOLOGICALLY CONTAMINATED TERRITORIES OF ZHYTOMYR OBLAST IN 2021

Objective: the key factors identification in radiation dose formation in population of radiologically contaminated areas of Zhytomyr oblast in the current period of accident through complex radiation and hygienic monitoring in reference settlements in 2021. Materials and methods. For complex radiation-hygienic monitoring in Zhytomyr oblast, 10 settlements were chosen – Narodychi, Selets, Bazar, Rudnya Bazarska, Khrystynivka – zone 2, Motiyki, Zalissya, Davydky, Radcha, Nova Radcha – zone 3 of Narodychi district, in which the highest radiation doses were recorded after the accident at the Chornobyl Nuclear Power Plant. The research was carried out in June 2021. In order to determine the doses of internal radiation, 645 measurements were performed on whole body counters (WBC) (478 adults and 167 children). The 44 samples of milk, 45 samples of potatoes and vegetables, and 38 samples of wild products were collected in local farms and measured for the 137Cs and 90Sr content. Residents of the studied settlements (n = 220, 175 adults, and 45 children) were interviewed about the levels of consumption of staple foodstuffs. External radiation doses were evaluated in all the studied settlements. Mathematical, dosimetry, and radiochemical methods were applied. Results and conclusions. Annual effective radiation doses of Zhytomyr oblast population in 2021 were formed mainly due to internal radiation ones that not exceeded 1.8 mSv · year-1 in adults and 0.5 mSv · year-1 in children against the radiologically contaminated territories (RCT) criterion of 1 mSv · year-1. Intake of 137Cs with milk and wild mushrooms, which traditionally occupy a significant part of diet in Zhytomyr oblast area and have consistently high levels of radioactive cesium contamination, remains a key factor of internal radiation dose forming in residents of the surveyed settlements of Zhytomyr oblast. Key words: comprehensive radiation and hygienic monitoring; radiologically contaminated territories; internal radiation dose; whole body counter; 137Cs and 90Sr content.