Gauthier-Lafaye F, Pourcelot L, Eikenberg J, Beer H, Le Roux G, Rhikvanov L P, Stille P, Renaud Ph, Mezhibor A
Centre de Géochimie de la Surface, EOST, CNRS/ULP, 1 rue Blessig, 67083 Strasbourg, France.
J Environ Radioact. 2008 Apr;99(4):680-93. doi: 10.1016/j.jenvrad.2007.09.008. Epub 2007 Nov 8.
Soils have been sampled in the vicinity of the Tomsk-Seversk facility (Siberia, Russia) that allows us to measure radioactive contaminations due to atmospheric and aquatic releases. Indeed soils exhibit large inventories of man-made fission products including 137Cs (ranging from 33,000 to 68,500 Bq m(-2)) and actinides such as plutonium (i.e. 239+240Pu from 420 to 5900 Bq m(-2)) or 241Am (160-1220 Bq m(-2)). Among all sampling sites, the bank of the Romashka channel exhibits the highest radioisotope concentrations. At this site, some short half-life gamma emitters were detected as well indicating recent aquatic discharge in the channel. In comparison, soils that underwent atmospheric depositions like peat and forest soils exhibit lower activities of actinides and 137Cs. Soil activities are too high to be related solely to global fallout and thus the source of plutonium must be discharges from the Siberian Chemical Combine (SCC) plant. This is confirmed by plutonium isotopic ratios measured by ICP-MS; the low 241Pu/239Pu and 240Pu/239Pu atomic ratios with respect to global fallout ratio or civil nuclear fuel are consistent with weapons grade signatures. Up to now, the influence of Tomsk-Seversk plutonium discharges was speculated in the Ob River and its estuary. Isotopic data from the present study show that plutonium measured in SCC probably constitutes a significant source of plutonium in the aquatic environment, together with plutonium from global fallout and other contaminated sites including Tomsk, Mayak (Russia) and Semipalatinsk (Republic of Kazakhstan). It is estimated that the proportion of plutonium from SCC source can reach 45% for 239Pu and 60% for 241Pu in the sediments.
已在托木斯克 - 谢韦尔斯克设施（俄罗斯西伯利亚）附近采集土壤样本，这使我们能够测量大气和水体排放造成的放射性污染。事实上，土壤中存在大量人造裂变产物，包括137Cs（范围为33,000至68,500 Bq m(-2)）以及锕系元素，如钚（即239 + 240Pu，范围为420至5900 Bq m(-2)）或241Am（160 - 1220 Bq m(-2)）。在所有采样点中，罗马什卡河河道岸边的放射性同位素浓度最高。在该地点还检测到一些半衰期短的伽马射线发射体，这表明河道近期有水体排放。相比之下，经历大气沉降的土壤，如泥炭土和森林土壤，其锕系元素和137Cs的活度较低。土壤活度过高，不可能仅与全球沉降有关，因此钚的来源必定是西伯利亚化学联合企业（SCC）工厂的排放。通过电感耦合等离子体质谱法（ICP - MS）测量的钚同位素比率证实了这一点；相对于全球沉降比率或民用核燃料，241Pu/239Pu和240Pu/239Pu的低原子比率与武器级特征相符。到目前为止，托木斯克 - 谢韦尔斯克钚排放对鄂毕河及其河口的影响一直是推测性的。本研究的同位素数据表明，SCC中测量到的钚可能是水生环境中钚的一个重要来源，此外还有来自全球沉降以及包括托木斯克、马亚克（俄罗斯）和塞米巴拉金斯克（哈萨克斯坦共和国）等其他受污染地点的钚。据估计，沉积物中来自SCC源的钚，对于239Pu可达45%，对于241Pu可达60%。
