Assessment of current natural and anthropogenic radionuclide activity concentrations in the bottom sediments from the Barents Sea

The article is devoted to the study of the activity values of natural radionuclides K-40, Th-232 and Ra-226 and technogenic radionuclide Cs-137 in the bottom sediments of the Barents Sea, which is distinguished from the rest of the Arctic seas by the fact that the largest number of radiation objects are concentrated here. The activity levels of natural radionuclides were within the range of activity values corresponding to marine sediments around the world. The highest radionuclide activities were found within the deepwater shelf of the Barents Sea. The current level of activity of the technogenic radionuclide Cs-137 is low and does not exceed 6.5 Bq center dot kg(-1). However, due to global climatic changes, the secondary source of radiation pollution of the sea may be the Novaya Zemlya ice sheet, in which huge quantities of technogenic radionuclides were deposited during atmospheric tests of the 1950s and 1960s.