Cesium-137 Concentration in the Surface Waters of Eurasian Seas: Evidence from the Expedition Research of 2017

Abstract

New data were obtained during Cruise 42 of the R/V Akademik Boris Petrov (January–March 2017) and Cruise 68 of the R/V Akademik Mstislav Keldysh (June–August 2017) on the concentration of the anthropogenic radionuclide cesium-137 in the surface waters of the East China Sea, South China Sea, equatorial Indian Ocean, Red Sea, Mediterranean Sea, Bay of Biscay, English Channel, Baltic Sea, North Atlantic, Norway Sea, and Barents Sea. Low cesium-137 concentrations were observed in the surface waters of the Eurasian seas. An exception is the Baltic Sea, where the cesium-137 content is much higher than the values obtained before the Chernobyl accident. Compared with previous estimates, higher cesium-137 concentration was observed in the surface water of the East China Sea, which could be related to the extensive discharge of high-level liquid radioactive waste after the Fukushima Daiichi nuclear accident of 2011.