New data on transuranium elements in the ecosystem of the Yenisei river floodplain

Abstract

The aim of the study is to investigate levels of transuranium elements in the ecosystem of the Yenisei river floodplain in the vicinity of the Mining-and-Chemical Combine of Rosatom. For the first time, the transuranium isotopes 243,244Cm have been detected in sediment, floodplain soil, and a berry shrub (Ribes nigrum – the blackcurrant) in the floodplain of the Yenisei river. The highest level of curium isotopes registered in the sediment of the Yenisei river is 21.4Bq/kg (dry), which is more than twice higher than maximum curium levels reported for soils sampled not far from the Chernobyl Nuclear Plant. Blackcurrant plants growing on radioactively contaminated soils contain the same transuranium elements as the soil (plutonium isotopes, americium, and curium). The highest activity concentrations of all transuranic elements have been found in ashed roots of the blackcurrant plants: 239,240Pu – 9.3Bq/kg, 241Am – 6.9Bq/kg, and 243,244Cm – 1.8Bq/kg. The highest soil-plant transfer factor (TF) for 243,244Cm is determined for roots – 0.073; the TF of 243,244Cm in berries is 0.027. The TF for 239,240Pu in berries is 0.006, which is several times lower than the TF for 243,244Cm. Analysis of our results and the literature data suggests that TFs for 243,244Cm are higher than those for 239,240Pu and 241Am.