Abstract
Advanced analytical techniques have enabled us to measure low elemental concentrations in environmental samples. Soil-to-plant transfer factors (TfS) of selected radionuclides have been collected using the stable elements. The TfS for stable elements, however, tend to be smaller than those of the radioisotopes. This might be mainly due to the difference in the ratio of extractable phase. In this study, the extractabilities of three elements (Mn, Zn, Sr) from an agricultural soil were examined with HCl solutions and compared between the stable elements and the radioisotopes (54Mn, 65Zn, 85Sr). Though all extraction ratios increased with HCl concentration, the ratios showed large differences between the stable elements and the radioisotopes. Almost all the 54Mn and 85Sr and about 60% of 65Zn were extracted by 2 N HCl, whereas the extraction ratios of the stable elements were lower by a factor of 2 to 13. These results suggest that stable elements are present in an unexchangeable form to a greater extent than the radioisotopes. Then transfer factors of stable elements would lead to underestimating the intake of anthropogenic radionuclides through the soil-plant pathway.
