Content of plutonium radionuclides in the bottom sediments of the salt lakes of the Crimean Peninsula in comparison with coastal areas of the Black Sea

The level of radioactive alpha-emitting radionuclides 239+240Pu activity concentration assessment in the surface (0–5 cm) bottom sediments from 10 Crimean salt lakes from 4 geographical groups was carried out. The highest values were observed in the lakes from different geographical groups: Kyzyl-Yar – (419 ± 27), Dzharylhach – (443 ± 24), Tobechik – (451 ± 43) mBq·kg-1 of 239+240Pu. The lowest values were observed in 3 studied lakes of Perekop group: Kiyat – (24 ± 6), Kirleut – (48 ± 4), Krasnoye – (95 ± 9) mBq·kg-1 of 239+240Pu. The comparative analysis showed that in the bottom sediment surface layer of the coastal Black Sea areas the 239+240Pu levels were on average twice as high as those in the surface bottom sediment of the salt lakes of the Crimean peninsula. The dose rates in the surface layer mud from the salt lakes were estimated to be within the natural radioactive background.