Thornberg C, Vesanen R, Wallström E, Zvonova I, Jesko T, Balonov M, Mattsson S
Department of Radiation Physics, Lund University, Malmö University Hospital, 205 02 Malmö, Sweden.
Radiat Environ Biophys. 2005 Oct;44(2):97-106. doi: 10.1007/s00411-005-0007-2. Epub 2005 Nov 2.
In 1990, a joint Nordic-Russian project was initiated in order to make independent estimations of the effective dose to selected groups of inhabitants in a highly contaminated area around the city of Novozybkov in the western Bryansk region of Russia. The inhabitants were living in six villages with initial contamination levels of (137)Cs between 0.9 and 2.7 MBq m(-2). Some villages had been decontaminated, others not. Both school children and adults participated in the study. The external irradiation of 100-130 inhabitants was determined during 1 month in September-October each year from 1990 to 2000 (except 1999), using individual thermoluminescent dosemeters. The body burden of (137,134)Cs was determined by in vivo measurements in about 500 inhabitants annually from 1991 to 2000, and for a subgroup also with analysis of the (137)Cs concentration in urine. The mean effective dose (E) from external and internal irradiation due to (137,134)Cs deposition varied between 2.5 and 1.2 mSv per year between 1990 and 2000. The total mean E decreased, on average, by 9% per year, while the mean external dose decreased by 16% per year. The dose rate from internal radiation decreased more slowly than the dose rate from external radiation, and also showed an irregular time variation. The contribution from the internal dose to the total E was 30-50%, depending on the village. Predictions for the long-term changes in the effective dose to people living in the areas are presented. The cumulated E for the 70 years following the accident was estimated to be about 90 mSv with the assumption that both internal and external dose decrease by 2% per year after year 2000. The highest E during a life-time received by single individuals living in the area may amount to around 500 mSv considering the individual variations in E.
1990年，北欧与俄罗斯启动了一个联合项目，旨在对俄罗斯布良斯克地区西部新兹布科夫市周边高污染区域内特定居民群体所受的有效剂量进行独立估算。这些居民生活在6个村庄，初始（137）铯污染水平在0.9至2.7 兆贝可每平方米之间。一些村庄已经进行了去污处理，另一些则没有。学童和成年人都参与了这项研究。1990年至2000年（1999年除外）期间，每年9月至10月的1个月内，使用个人热释光剂量计测定了100 - 130名居民的外照射剂量。1991年至2000年期间，每年对约500名居民进行体内测量以确定（137,134）铯的体内负荷，对于一个亚组还分析了尿液中（137）铯的浓度。1990年至2000年期间，由于（137,134）铯沉积导致的外照射和内照射的平均有效剂量（E）在每年2.5至1.2毫希沃特之间变化。总平均E每年平均下降9%，而平均外照射剂量每年下降16%。内照射剂量率的下降比外照射剂量率更慢，并且还呈现出不规则的时间变化。内照射剂量对总E的贡献为30% - 50%，具体取决于村庄。给出了对该地区居民有效剂量长期变化的预测。假设2000年后内照射和外照射剂量每年都下降2%，事故后70年的累积E估计约为90毫希沃特。考虑到E的个体差异，居住在该地区的单个人一生中所接受的最高E可能达到约500毫希沃特。
