Levels of Activity Concentration, Migration and Dose Rates on Biota from Alpha-Radioisotopes of Plutonium in the Black Sea Ecosystem

Abstract

The Black Sea received abundant amount of plutonium alpha–emitting radionuclides 238,239,240Pu with global fallout after nuclear weapon testing in atmosphere and after accident on the Chernobyl nuclear power plant (ChNPP) in 1986. Distribution of plutonium radionuclides in abiotic (water and bottom sediment) and biotic (algae, mollusks, fish) components of the Black Sea ecosystems was studied during the post–Chernobyl period at different areas as a rule at western and central parts of the sea. This study is devoted to the analysis of a radioecological situation in the Black Sea and concerns the levels of contamination and redistribution of the 239,240Pu in the abiotic and biotic components of the sea ecosystem. The long–term accumulation and migration trends of these radionuclides were analyzed concerning abiotic components of the Black Sea after the ChNPP accident. Zones were revealed that have an increased ability to accumulate these radioactive pollutants. The estimations of the fluxes of elimination of the after-accidental plutonium alpha–radionuclides into bottom sediments in open and coastal areas of the sea were obtained. Evaluation of irradiation dose rates formed with alpha–radiation of 239,240Pu in Black Sea hydrobionts was carried out. Important quantitative characteristics of plutonium migration in the Black Sea ecosystems were obtained and application of the comparative analysis together with equidosimetric approach to the ecological effects assessment from the 239,240Pu doses on hydrobionts in contemporary radiological situation in the Black Sea as well as in different potential radioecological situations in wide range of alpha-emitting plutonium radionuclides concentration activity in seawater was fulfilled.