Open AccessAssessment of the current levels of 241Am and 137Сs in soils and foodstuff, as well as of public internal exposure to ionizing radiation in populated areas adjacent to the Chernobyl NPP exclusion zone (case study: the Bragin district of the Gomel region, Belarus)
Author(s) -
Е. К. Нилова,
В. Н. Бортновский,
С. А. Тагай,
Н. В. Дударева,
A.N. Nikitin
Publication year - 2020
Publication title -
radiacionnaâ gigiena
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.254
H-Index - 5
ISSN - 1998-426X
DOI - 10.21514/1998-426x-2020-13-3-25-37
Subject(s) - soil water , radionuclide , environmental science , human settlement , contamination , environmental chemistry , soil test , internal dose , leafy vegetables , toxicology , chemistry , geography , soil science , radiochemistry , biology , ecology , food science , archaeology , physics , quantum mechanics
This paper is part of a research cycle focusing on studying the current levels of 241 Am and 137 Cs in soils and local foodstuffs of populated areas neighboring the Chernobyl exclusion zone. Our objective was to estimate the maximum annual committed internal doses to individuals of the Bragin-area settlements from inhalation and consumption of locally produced foods. We updated the data on the levels of 241 Am and 137 Сs in soils of 28 settlements of the district. Specific activity of 241 Am in soils in two of the settlements were the highest of all; we took and analyzed samples of local-grown foodstuff. 241 Am in food samples was measured via a radiochemical method with the use of selective chromatographic resins and alpha-spectrometry measurement. A gammaspectrometry technique was used to measure 241 Am in soil and 137 Сs in soil and food samples. The most contaminated by 241 Am and 137 Cs appeared the soils in the town of Bragin, the administrative center of the district where the respective levels were as high as 2.8 and 560 kBq/m2. Among the analyzed samples, the specific activities of 241 Am in root and tuber crops were one-digit values, while the samples of leafy vegetables contained a few tens of mBq/kg of the same radionuclide. That said, however, 241 Am concentrations in food samples were lower than those of 137 Сs by three orders of magnitude. The results showed an apparent difference between estimated annual committed internal doses to the Bragin residents due to 241 Am intake and that resulting from 137 Сs with the respective 0.03 and 1.7 mSv/year. The maximum doses to population of the Bragin-district villages from inhalation of 241 Am varied from 0.006 to 0.033 mSv/year exceeding the doses from inhaled 137 Сs – 0.0002-0.002 mSv/year – by one order of magnitude. The major contribution to the public internal exposure today is 137 Сs intake through consumption of contaminated food that produced locally; its contribution is about 93-99% of the total internal dose received by the Bragin-district residents.