Americium, plutonium, cesium and cobalt uptake by earthworm Eisenia andrei in contaminated soil

Abstract The suitability of earthworms (Eisenia andrei) for the vermiremediation of soils contaminated with radionuclides was tested after 241Am, 239Pu, 137Cs and 60Co uptake from the soil. The accumulation of radioactivity in earthworms was measured after 3, 7, 15, 30, 45, 60, 80, 100 days of establishment in the case of gamma radionuclides and after 1, 15, 79, 93, 100, 113 for alpha radionuclides. Radiochemical analysis of alpha radionuclides was performed by the extraction chromatography using commercial sorbents TEVA resin and DGA Resin. Gamma radionuclides were measured by gamma spectrometry on HPGe detector. Although the enhanced uptake 241Am, 239Pu, 137Cs and 60Co by earthworms was observed, low values of transfer factors have been achieved. However, radioecological characteristic of Am and Pu are rare, therefore, our investigation will fill some gaps in the knowledge. The calculation of transfer factors was provided for various periods of exposition. One of the findings is that Pu has a longer biological half-life than Am. Moreover, there is also confirmation that Co has a longer biological half-life than Cs. The dependence of the mentioned radionuclides on the time of contact with the contaminated medium was also observed