The present radiological situation at the nuclear weapons test site at Semipalatinsk in Kazakhstan with regard to plutonium contamination

摘要

The preliminary results of measurements of plutonium and other radioisotopes in soil and vegetation samples originating from the former Soviet Union's nuclear test site of Semipalatinsk (STS) in Kazakhstan are presented. Sampling sites were chosen to cover agriculturally used land to receive information on contamination levels of products foreseen for human consumption and to estimate doses to the population. Here the measured activity concentrations of ~(238)Pu and ~(239, 240)Pu in selected samples are given and their impact on humans is discussed. In most cases (67 and 75%, respectively) at the two highly contaminated sites of the STS, the activity concentrations in soil samples were below 30 Bq kg~(-1) (~(239, 240)Pu) and 5 Bq kg~(-1) (~(238)Pu) for Lake Balapan and below 25 Bq kg~(-1) (~(239, 240)Pu) or 6 Bq kg~(-1) (~(238)Pu) for Ground Zero.