RESULTS OF WBC-MONITORING OF FIREFIGHTERS PARTICIPATING IN RESPONSE TO CHORNOBYL FOREST FIRES IN APRIL-MAY 2020. / REZUL'TATY LVL-MONITORYNGU POZhEZhNYKh, ShchO BULY ZADIIaNI U GASINNI LISOVOÏ POZhEZhI V ZONI VIDChUZhENNIa ChAES U KVITNI­TRAVNI 2020 ROKU.

OBJECTIVE: of this study was to determine the levels of radionuclides in the rescuers' bodies of the SES during firefighting in the exclusion zone of the Chornobyl nuclear power plant and to assess the dose of internal radiation dueto this receipt. MATERIALS AND METHODS: From 06.04.2020 to 19.05.2020 in the State Institution «National Research Center forRadiation Medicine of the National Academy of Medical Sciences of Ukraine¼ (NRCRM) measurements of the contentof incorporated gamma radionuclides on whole body counters (WBC) operational class «Screener-3M¼ (Minimumdetected activity (MDA) is 300-500 Bq for 5 minutes of measurement at 137Cs) and expert high-sensitivity WBC (MDAis 20 Bq for 10 minutes of measurement at 137Cs). 470 people (523 measurements) in three groups of personnel ofthe SES of Ukraine who took part in the forest fire liquidation in the exclusion zone in the period from April 4 toMay 5, 2020 were examined. Mathematical and spectrometric methods are used in the work. RESULTS AND CONCLUSIONS: In the vast majority (95 %) of the personnel of the SES of Ukraine, examined at the WBCoperational class «Screener-3M¼ (more than 500 measurements), the assessment of the values of the individualeffective dose of internal radiation due to 137Cs in the body during firefighting, assuming that it receipt occurredduring operation in the exclusion zone, did not exceed the minimum dose detected by MDD (5-14 µSv). The average value of the effective dose of internal radiation in the group of personnel of the State Emergency Service ofUkraine in Kyiv, which participated in the elimination of forest fires in the exclusion zone from April 4 to May 5, 2020(26 people) studied at the expert WBC, is 2.5 ± 1.1 µSv, in the group of personnel of the SES of Ukraine in Cherkasyregion, which participated in the fire on April 19-24, 2020 (9 people) - 2.2 ± 0.6 µSv, in the group of personnel ofthe SES of Ukraine in the Kyiv region, which took part in the elimination of the forest fire in the exclusion zone onApril 4 - May 5, 2020 (42 people) - 4.4 ± 2.4 µSv. Maximum values of 5.1 µSv, 3.5 µSv, 11.8 µSv in the groups ofKyiv city, Cherkasy and Kyiv regions, respectively, which is much lower than the basic dose limit for the populationfrom man-made sources of 1000 µSv · year-1 according to the Law of Ukraine about protection of the person againstinfluence of ionizing radiation.

Main internal dose forming factors for inhabitants of contaminated regions at current phase of the Chernobyl nuclear power plant accident (Kyiv region as an example). / OSNOVNI ChYNNYKY FORMUVANNIa VNUTRIShN'OGO OPROMINENNIa NASELENNIa RADIOAKTYVNO ZABRUDNENYKh TERYTORIY NA POTOChNOMU ETAPI AVARII NA ChAES (NA PRYKLADI KYIVS'KOI OBLASTI).

UNLABELLED: Objective of this work is revealing of main dose forming factors of internal doses for inhabitants of contaminated regions of Kyiv region relying on the results of integral dosimetric monitoring. MATERIALS AND METHODS: Three villages have been chosen for the investigation. They are: Raghivka, Zelena Poliana (Poliske district), Karpylivka (Ivankiv district). Twice a year, in May and in October those villages' residents were inspected for content of incorporated 137Cs. They were measured by direct method at the place of residence with the help of whole body counters (WBC). The principal food samples were collected for detection of 90Sr and 137Сs content. Those villages' inhabitants were interviewed about food consumption levels. Mathematical, dosimetric and radio chemical methods were used in this workResults and conclusions. The estimation of internal doses due to intake of 137Cs by ingestion of milk and potatoes are in the range 0.3-34% of doses estimated on the base of WBC data. The contribution to the dose of internal expo sure from intake of 137Cs with the milk consumption is no more than two times higher than the contribution of pota toes consumption in the case of equal consumption levels of these products. Contributions to the dose of internal exposure from intake of 90Sr with milk and potatoes consumptions are approximately similar. Consumption of mush rooms and other wild nature products by inhabitants from the inspected settlements is the main forming factor of internal dose due to 137Cs intake.

Regulation of the radionuclide content in commodities produced in areas affected by the Chornobyl accident. / Reguljuvannja vmistu radionuklidiv u tovarah, vyroblenyh na terytorijah, shho postrazhdaly vnaslidok avarii' na ChAES.

This paper discusses the approaches to regulation of the content of radionuclides in commodities and compares the international and Ukrainian standards, which establish permissible levels of the content of radionuclides in food-stuffs produced in the Chornobyl-affected areas. The paper gives the actual monitoring data and discusses the main causes of differences between Ukrainian, European and international standards. The need for improvement of current approaches to the regulation of the content of radionuclides in commodities is highlighted.