Radioactivity of anthropogenic and natural radionuclides in marine sediments of the Chaun Bay, East Siberian Sea

Alexander Ulyantsev; Sergei Ivannikov; Svetlana Bratskaya; Alexander Charkin

doi:10.1016/j.marpolbul.2023.115582

Radioactivity of anthropogenic and natural radionuclides in marine sediments of the Chaun Bay, East Siberian Sea

Mar Pollut Bull. 2023 Oct:195:115582. doi: 10.1016/j.marpolbul.2023.115582. Epub 2023 Sep 23.

Authors

Alexander Ulyantsev¹, Sergei Ivannikov², Svetlana Bratskaya², Alexander Charkin³

Affiliations

¹ Shirshov Institute of Oceanology, Russian Academy of Sciences, 117997 Moscow, Russia. Electronic address: uliantsev.as@ocean.ru.
² Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022 Vladivostok, Russia.
³ Il'ichev Pacific Oceanological Institute, Far Eastern Branch of the Russian Academy of Sciences, 690041 Vladivostok, Russia.

PMID: 37748418
DOI: 10.1016/j.marpolbul.2023.115582

Abstract

Natural radioactive isotopes serve as a useful proxy of geological and geochemical processes in marine environment, while radiocesium serves as an indicator of man-made contamination. Monitoring of natural and anthropogenic radioactivity under conditions of the climate changes in the Arctic region is of high importance in investigations of this natural system. For the first time, we report the data on spatial distribution of natural (²³²Th, ²²⁶Ra, ⁴⁰K) and anthropogenic (¹³⁷Cs) radionuclide activities in the marine sediments from Chaun Bay (East Siberian Sea). The measured activity concentrations varied in the range 23.7-77.9 (mean 39.2) Bq kg^-1 for ²³²Th, 16.5-39.3 (mean 26.6) Bq kg^-1 for ²²⁶Ra, 535-991 (mean 726) Bq kg^-1 for ⁴⁰K, and 0.5-4.7 (mean 2.0) Bq kg^-1 for ¹³⁷Cs. The radiocesium level in the sediments showed no local sources of anthropogenic pollution in the Chaun Bay, while the average activity concentration of ⁴⁰K was 1.8 times higher than worldwide.

Keywords: Arctic; Gamma-spectrometry; Grain size; Marine sediments; Natural radionuclides; Radiocesium.