In this study, distribution coefficients (K(d)s) of five radionuclides (Mn-54, Co-60, Zn-65, Sr-85, Cs-137) were measured by a batch technique for 36 agricultural soils (paddy and upland soils)collected in Japan. Twelve properties of the soils and measured K(d)s were examined for their probability distributions. Soil properties showed log-normal type distributions, except pH(H2O), and total calcium and potassium contents for which distributions were normal. The K-d distributions were also log-normal types except for Mn-54-K-d. No significant difference in soil K-d was found between upland and paddy soils. The K(d)s were analyzed for correlations with each soil property. The combinations showing the highest correlation were: the exchangeable calcium for Mn-54 and Co-60; the water content for Zn-65; the cation exchange capacity for Sr-85; and the exchangeable potassium for Cs-137. For Mn-54 and Co-60, their K(d)s also correlated with supernatant pH. Only Sr-85-K-d showed an adequate correlation with the value of the CBC divided by the supernatant EC. For the other four nuclides, some other mechanisms besides ion exchange seemed to be working.
