Robison W L, Bogen K T, Conrado C L
Health & Ecological Assessment Division, Lawrence Livermore National Laboratory, CA 94550-9900, USA.
Health Phys. 1997 Jul;73(1):100-14. doi: 10.1097/00004032-199707000-00008.
On 1 March 1954, a nuclear weapon test, code-named BRAVO, conducted at Bikini Atoll in the northern Marshall Islands contaminated the major residence island. There has been a continuing effort since 1977 to refine dose assessments for resettlement options at Bikini Atoll. Here we provide a radiological dose assessment for the main residence island, Bikini, using extensive radionuclide concentration data derived from analysis of food crops, ground water, cistern water, fish and other marine species, animals, air, and soil collected at Bikini Island as part of our continuing research and monitoring program that began in 1978. The unique composition of coral soil greatly alters the relative contribution of 137Cs and 90Sr to the total estimated dose relative to expectations based on North American and European soils. Without counter measures, 137Cs produces 96% of the estimated dose for returning residents, mostly through uptake from the soil to terrestrial food crops but also from external gamma exposure. The doses are calculated assuming a resettlement date of 1999. The estimated maximum annual effective dose for current island conditions is 4.0 mSv when imported foods, which are now an established part of the diet, are available. The 30-, 50-, and 70-y integral effective doses are 91 mSv, 130 mSv, and 150 mSv, respectively. A detailed uncertainty analysis for these dose estimates is presented in a companion paper in this issue. We have evaluated various countermeasures to reduce 137Cs in food crops. Treatment with potassium reduces the uptake of 137Cs into food crops, and therefore the ingestion dose, to about 5% of pretreatment levels and has essentially no negative environmental consequences. We have calculated the dose for the rehabilitation scenario where the top 40 cm of soil is removed in the housing and village area, and the rest of the island is treated with potassium fertilizer; the maximum annual effective dose is 0.41 mSv and the 30-, 50-, and 70-y integral effective doses are 9.8 mSv, 14 mSv, and 16 mSv, respectively.
1954年3月1日，在北马绍尔群岛比基尼环礁进行的一次代号为“布拉沃”的核武器试验污染了主要居住岛屿。自1977年以来，一直在持续努力完善比基尼环礁重新安置方案的剂量评估。在此，我们利用作为我们始于1978年的持续研究和监测计划的一部分，从比基尼岛采集的粮食作物、地下水、蓄水池水、鱼类及其他海洋物种、动物、空气和土壤分析中获得的大量放射性核素浓度数据，对比基尼主要居住岛屿进行了辐射剂量评估。珊瑚土壤的独特成分极大地改变了相对于基于北美和欧洲土壤的预期，137Cs和90Sr对总估计剂量的相对贡献。在没有应对措施的情况下，137Cs产生了返回居民估计剂量的96%，主要是通过从土壤吸收到陆地粮食作物中，但也来自外部伽马照射。剂量是假设1999年重新安置日期计算的。当现在已成为饮食既定组成部分的进口食品可用时，当前岛屿条件下估计的最大年有效剂量为4.0毫希沃特。30年、50年和70年的累积有效剂量分别为91毫希沃特、130毫希沃特和150毫希沃特。本期的一篇配套论文中给出了这些剂量估计的详细不确定性分析。我们评估了各种减少粮食作物中137Cs的应对措施。用钾处理可将137Cs吸收到粮食作物中的量以及因此的摄入剂量降低到预处理水平的约5%，并且基本上没有负面环境影响。我们计算了在住房和村庄区域去除顶部40厘米土壤，岛屿其他区域施用钾肥的恢复方案的剂量；最大年有效剂量为0.41毫希沃特，30年、50年和70年的累积有效剂量分别为9.8毫希沃特、14毫希沃特和
