这项研究考虑了白俄罗斯受污染最严重的Gomel和Mogilev州的人口暴露于切尔诺贝利事故造成的长期辐射源。开发了剂量重建方法,并将其应用于这项研究中,以估计(i)来自地面上沉积的γ发射放射性核素的外部辐射和(ii)134Cs的红骨髓剂量(RBM)。137Cs和90Sr与当地生产的食品一起摄入。Gomel和Mogilev州的成年居民在切尔诺贝利事故后35年累积的平均人口加权RBM剂量分别为12和5.7mGy,分别,而最年轻年龄组的剂量降低了20-40%。1986-2021年,在Narovlya,成年人的平均区域特异性RBM剂量最高,分别为63、56和46mGy,Gomel州的Vetka和Korma地区,分别。对于大多数地区来说,外照射是暴露的主要途径(占总剂量的60-70%),除137Cs土壤对牛乳的聚集系数极高的地区外(≥5.0BqL-1/kBqm-2),其中134Cs和137Cs摄入对总RBM剂量的贡献超过70%。在Gomel和Mogilev州的大多数地区,90Sr摄入量对成人总RBM剂量的贡献不超过4%,新生儿不超过10%。本研究中估计的剂量的有效性是通过与1987-2015年热释光剂量计和全身计数器测量获得的剂量进行比较来评估的。本研究中开发的方法可用于计算除RBM以外的靶器官的剂量,例如甲状腺和乳腺剂量。本研究中估计的年龄依赖性和人口加权剂量对生态流行病学研究很有用,辐射风险的预测,以及对暴露于切尔诺贝利辐射的人群进行分析流行病学研究的理由。
This study considers the exposure of the population of the most contaminated Gomel and Mogilev Oblasts in Belarus to prolonged sources of irradiation resulting from the Chernobyl accident. Dose reconstruction methods were developed and applied in this study to estimate the red bone-marrow doses (RBMs) from (i) external irradiation from gamma-emitting radionuclides deposited on the ground and (ii)
134Cs, 137Cs and 90Sr ingestion with locally produced foodstuffs. The mean population-weighted RBM doses accumulated during 35 years after the Chernobyl accident were 12 and 5.7 mGy for adult residents in Gomel and Mogilev Oblasts, respectively, while doses for youngest age groups were 20-40% lower. The highest mean area-specific RBM doses for adults accumulated in 1986-2021 were 63, 56 and 46 mGy in Narovlya, Vetka and Korma raions in Gomel Oblast, respectively. For most areas, external irradiation was the predominant pathway of exposure (60-70% from the total dose), except for areas with an extremely high aggregated 137Cs soil to cow\'s milk transfer coefficient (≥ 5.0 Bq L-1 per kBq m-2), where the contribution of
134Cs and 137Cs ingestion to the total RBM dose was more than 70%. The contribution of 90Sr intake to the total RBM dose did not exceed 4% for adults and 10% for newborns in most raion in Gomel and Mogilev Oblasts. The validity of the doses estimated in this study was assessed by comparison with doses obtained from measurements by thermoluminescence dosimeters and whole-body counters done in 1987-2015. The methodology developed in this study can be used to calculate doses to target organs other than RBM such as thyroid and breast doses. The age-dependent and population-weighted doses estimated in this study are useful for ecological epidemiological studies, for projection of radiation risk, and for justification of analytical epidemiological studies in populations exposed to Chernobyl fallout.