Content of technogenic radionuclides in water, bottom sediments and benthos of the Kara sea and shallow bays of the Novaya zemlya archipelago

Abstract

During the expedition on the Akademik Mstislav Keldysh research vessel in 2016 year it was established that the content of radioactive cesium in the sea water of the Novaya Zemlya archipelago bays and open sea are at a level corresponding to the global fallout (1 Bq /m3). Plutonium content in water is slightly higher .The activity of neptunium
 in water is an order of magnitude higher than the activity of plutonium (0.761.89 Bq/m3), although its content in global fallout is almost two orders of magnitude lower than the plutonium content. The plutonium content in the bottom sediments of the Kara Sea is 0.23.8 Bq/kg. The content of radioactive cesium is as high as possible in the mouth of the Yenisei River (up to 21 Bq/kg) Analysis of benthic samples showed that the content of radioactive cesium and plutonium in samples taken in the bays of the Novaya Zemlya archipelago is below the detection limit. The neptunium content in the benthos samples is above the detection limit and amounts to 180 Bq/kg wet weight. It was showed that the content of neptunium in benthos is one of the indicators of radioactive contamination of the marine environment.