ARKHANGELSK, July 8. /TASS/. Scientists of the Arctic Floating University expedition began sampling the Barents Sea bottom sediments to study their radioactivity. Bottom sediments studies are most informative for determining radioactivity dynamics in the Arctic, said Andrey Puchkov, a senior researcher at the Environmental Radiology Laboratory of the Laverov Federal Research Center for Integrated Arctic Studies (the Russian Academy of Sciences' Urals Branch)

"The focus on sampling bottom sediments will be an important aspect of this expedition," he said on board the Professor Molchanov scientific research vessel. "In previous years, specialists sampled seawater, but, from the practical point of view, bottom sediments studies are more informative. Radioactive elements and other pollutants entering the water settle and accumulate there."

Scientists analyze bottom soils as they are a natural archive of the marine environment's ecological conditions. Radiologists will compare obtained data with results of studies conducted in 2019, 2020 and 2024 to see the dynamics of changes in man-made and natural radionuclides' activities in bottom sediments.

"The Arctic ecosystem is very fragile. Its buffering abilities are extremely low, so it is very difficult for it to withstand various types of pollution, including radioactivity," the laboratory's leader Evgeny Yakovlev said. "Given the multiplicity of existing man-made sources of radiation (tests on Novaya Zemlya archipelago, explosions and accidents in other regions of the planet), we continue studying in which environments radiation is concentrated and absorbed."

Man-made radionuclides include caesium-137, which has been released into the atmosphere most of all as a result of nuclear tests and accidents. Experts will also determine the content of plutonium in bottom sediments. The study of natural radioactivity is equally important. Natural radioactivity in the Arctic archipelagos is related to the rocks' geological structure and features, the scientist continued. For example, natural radioactivity in some areas of Novaya Zemlya may be higher than on the continent since there prevail clay shales enriched with natural radionuclides: uranium, thorium, and potassium-40.

During the expedition, the Center's specialists will give lectures on radiology as part of the Arctic Floating University's educational block. "We hope that during this expedition, new young scientists, passionate about research in the Arctic, will join the Russian science," he added.

About the expedition

The 20th voyage of the Arctic Floating University scientific and educational expedition runs from July 1 to July 22, 2026 on board the Professor Molchanov scientific research vessel. The expedition organizers are: the Lomonosov Northern Arctic Federal University and the Northern Department for Hydrometeorology and Environmental Monitoring (Sevhydromet). The project's official sponsors and partners are: the Russian Federation's Ministry of Science and Higher Education, the Russian Geographical Society, general sponsor - VTB, the Norilsk Nickel Company, and the Floating University Coordination Center based at the Moscow Institute of Physics and Technology (MIPT).