Mosses are collectors of anthropogenic pollution and are suitable as bioindicators for the content of heavy metals and radionuclides in the air. Due to their lack of a real root system, the main way nutrients are supplied to them is through air moisture. Airborne substances are absorbed and retained in the moss, even when these plants are thousands of kilometers from the source of pollution. In regard to radionuclides, mosses are very indicative. The subject of the research are mosses from Livingstone Island, South Shetland Islands, Antarctica. The presence of natural and man-made radionuclides is investigated. The presence of Natural and man-made radionuclides were determined by means of gamma-spectrometry. The content of Pb-210, U-238, Ra-226, Pb-214, Bi-214, Th-232, K-40, Cs-137 was determined. The activity of cesium-137 is between 3.5±1.2 and 11±2 Bq/kg, for Pb-210 - between 68±7 и 163±15 Bq/kg. Results from samples taken in 2012 and 2022 are compared. This allows to assess the current state of the Antarctic ecosystem and to ascertain changes over a 10-year period. The research confirms that even the most distant points on the globe are contaminated with radionuclides.

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Milena Hristozova, Radoslava Lazarova, Ivanka Yordanova, Viktoria Nedyalkova, "Content of natural and man-made radionuclides in Antarctic mosses", RAD Conf. Proc, vol. 7, 2023, pp. 20-23; http://doi.org/10.21175/RadProc.2023.04