Radioactive contamination around the former Soviet Union's Semipalatinsk nuclear test site and estimation of internal radiation dose for people

前苏联塞米巴拉金斯克核试验场周围放射性污染及人体体内辐射剂量估算

基本信息

批准号：
16404004
负责人：
YAMAMOTO Masayoshi
金额：
$ 7.23万
依托单位：
Kanazawa University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2005
项目状态：
已结题

项目摘要

Nuclear weapon tests by the former USSR at the Semipalatinsk Nuclear Test Site (SNTS) in Kazakhstan caused a vast amount of radioactive contamination around the test site. Dolon village is known as one of the most contaminated villages by radioactive fallout around SNTS. Calculated external gamma-ray dose in air by model ranged from 1 to 2 Gy, while TL measurement of a brick sample n Dolon taken from a church was close to about 0.5 Gy. Thus, In Dolon village, some discrepancies in the dose estimation for the village among investigators were pointed out. In relation to the effort to reconstract the radiation dose in Dolon village, the width and center-axis location of the radioactive plume were investigated based on the soil contamination data around Dolon and the nearby villages. Additional soil contamination data around Dolon were obtained during the period of this study. As a result, the plotted distribution formed a peak-like shape for Cs-137 and Pu-239,240. The center part of the plume passed over the residential area of Dolon with one sigma value of 1.5 km. Finally, 0.50 Gy of absorbed dose in air was derived as our tentative estimate for 1-year cumulative external dose in Dolon due to local fallout from the first USSR test in 1949.Parallel to the above works, to evaluate the present Pu and Cs-137 levels in the general population living near the SNTS and to estimate the associated alpha doses, Pu-239,240 and U isotopes in bone samples from more than 70 autopsies of residents were measured. By assuming that average concentration of Pu-239,240 in bone samples is the value at 45 years after instantaneous inhalation in 1955,the initial total and the effective dose for 45 years were estimated as 10 Bq and 1.2 mSv, respectively. The annual intake of total U and its effective dose for 60 years were estimated as 30 Bq for adult and 0.1 mSv, respectively, for chronic ingestion.

前苏联在哈萨克斯坦塞米巴拉金斯克核试验场（SNTS）进行的核武器试验造成试验场周围大量放射性污染。多伦村被认为是 SNTS 周围放射性沉降物污染最严重的村庄之一。通过模型计算得出的空气中外部伽马射线剂量范围为 1 至 2 Gy，而从教堂采集的多隆砖块样品的 TL 测量值接近约 0.5 Gy。因此，在多伦村，调查人员对该村的剂量估算存在一些差异。针对多伦村辐射剂量重建工作，根据多伦及附近村庄的土壤污染数据，对放射性羽流的宽度和中心轴位置进行了调查。在本研究期间获得了多伦周围的其他土壤污染数据。结果，Cs-137 和 Pu-239,240 的绘制分布形成了峰状形状。羽流的中心部分经过多隆居民区，1西格玛值为1.5公里。最后，由于 1949 年苏联第一次试验的局部影响，我们对多隆 1 年累积外部剂量的初步估计得出了空气中 0.50 Gy 的吸收剂量。与上述工作并行，评估目前的 Pu 和 Cs-居住在 SNTS 附近的一般人群中的 137 个水平，并估计来自 70 多个骨样本中的相关 α 剂量、Pu-239,240 和 U 同位素对居民进行尸检。假设骨样品中Pu-239,240的平均浓度为1955年瞬时吸入后45年的值，则估计45年的初始总剂量和有效剂量分别为10 Bq和1.2 mSv。 60 年总 U 的年摄入量及其有效剂量估计分别为成人 30 Bq 和慢性摄入 0.1 mSv。