Radioactive Contamination and Doses of Internal Irradiation of Fish in the Deep Lake of the Chornobyl Exclusion Zone

Abstract

After the accidents at the Chornobyl and Fukushima NPPs, the specific activity of radionuclides in fish in radioactively contaminated reservoirs reached hundreds of kBq kg-1. Over time, as the radiological situation improved, there was a decrease in radioactive contamination of fish, but even now there are cases of exceeding the permissible levels of radionuclides in food. This work aimed to determine in real conditions the content of 90Sr and 137Cs in different species of fish in one of the most radioactively contaminated reservoirs of the Chornobyl Exclusion Zone - Glubokoye lake. As a result of experimental studies conducted from 2016 to 2021, the values of the specific activity of 90Sr and 137Cs in different species of fish were obtained, which were hundreds of times higher than the permissible levels. It is shown that without the use of countermeasures, this situation will persist for several decades. The results show that the internal radiation doses of fish due to the level of their radioactive contamination do not exceed the permissible levels recommended by international organizations for radiation protection of the environment.