137Cs exposure in the Marshallese populations: an assessment based on whole-body counting measurements (1989-1994).
137Cs exposure in the Marshallese populations: an assessment based on whole-body counting measurements (1989-1994).
复制标题
马绍尔人群中的 137C 暴露：基于全身计数测量的评估（1989-1994 年）。
作者：
L. C. Sun;J. Clinton;E. Kaplan;C. B. Meinhold
马绍尔群岛是美国多次进行核武器试验的地点。从1946年到1958年，核装置在埃尼韦塔克和比基尼环礁被引爆。在1954年布拉沃试验的北部岛屿下风意外污染之后，布鲁克海文国家实验室开始参与受影响人口的医疗保健和辐射安全。评估体内放射性核素沉积的一项重要技术是全身计数。为了估计当前和未来对137Cs的暴露，本文分析了1989年至1994年的数据并进行了报告。在此期间，为马绍尔群岛进行了3 618次测量。体内的铯含量被认为是由一系列的长期摄入造成的。此外，假定体内铯的活度达到一个稳定期，并维持365天以上。我们根据国际放射防护委员会的建议估计了每个人群的年有效剂量率。用全身计数法测量的137Cs的平均摄取量因人群而异；这与外界暴露率的测量结果一致。该分析虽然基于有限的数据，但表明对137Cs的吸收没有季节性影响的统计支持。铯摄取的临界人群是成年男性。在5年的监测期内，所有对137Cs的内部暴露量均小于0.2毫西弗（-1）。同样，马朱罗居民的持续平均铯有效剂量率为2微西弗（-1）。
The Marshall Islands were the site of numerous tests of nuclear weapons by the United States. From 1946 to 1958, nuclear devices were detonated at Enewetak and Bikini Atolls. Following the inadvertent contamination of the northern islands downwind of the 1954 Bravo Test, Brookhaven National Laboratory became involved in the medical care and the radiological safety of the affected populations. One important technique employed in assessing the internally deposited radionuclides is whole-body counting. To estimate current and future exposures to 137Cs, data from 1989 to 1994 were analyzed and are reported in this paper. During this period, 3,618 measurements were made for the Marshallese. The cesium body contents were assumed to result from a series of chronic intakes. Also, it was assumed that cesium activity in the body reaches a plateau that is maintained over 365 d. We estimated the annual effective dose rate for each population, derived from the recommendations of the International Commission on Radiological Protection. The average 137Cs uptake measured by the whole-body counting method varies from one population to another; it was consistent with measurements of external exposure rate. The analysis, though based on limited data, indicates that there is no statistical support for a seasonal effect on 137Cs uptake. The critical population group for cesium uptake is adult males. Within the 5-y monitoring period, all internal exposures to 137Cs were less than 0.2 mSv y(-1). Similarly, a persistent average cesium effective dose rate of 2 microSv y(-1) was determined for Majuro residents.