Lessard E T, Miltenberger R P, Cohn S H, Musolino S V, Conard R A
Health Phys. 1984 Mar;46(3):511-27. doi: 10.1097/00004032-198403000-00002.
From June 1946 to August 1958, the U.S. Department of Defense and the U.S. Atomic Energy Commission (AEC) conducted nuclear weapons tests in the Northern Marshall Islands. On 1 March 1954, BRAVO, an above-ground test in the Castle series, produced high levels of radioactive material, some of which subsequently fell on Rongelap and Utirik Atolls due to an unexpected wind shift. On 3 March 1954, the inhabitants of these atolls were moved out of the affected area. They later returned to Utirik in June 1954 and to Rongelap in June 1957. Comprehensive environmental and personnel radiological monitoring programs were initiated in the mid 1950s by Brookhaven National Laboratory to ensure that body burdens of the exposed Marshallese subjects remained within AEC guidelines. Their body-burden histories and calculated activity ingestion rate patterns post-return are presented along with estimates of internal committed effective dose equivalents. External exposure data are also included. In addition, relationships between body burden or urine-activity concentration and declining continuous intake were developed. The implications of these studies are: (1) the dietary intake of 137Cs was a major component contributing to the committed effective dose equivalent for the years after the initial contamination of the atolls; (2) for persons whose diet included fish, 65Zn was a major component of committed effective dose equivalent during the first years post-return; (3) a decline in the daily activity ingestion rate greater than that resulting from radioactive decay of the source was estimated for 137Cs, 65Zn, 90Sr and 60Co; (4) the relative impact of each nuclide on the estimate of committed effective dose equivalent was dependent upon the time interval between initial contamination and rehabilitation; and (5) the internal committed effective dose equivalent exceeded the external dose equivalent by a factor of 1.1 at Utirik and 1.5 at Rongelap during the rehabitation period. Few reliable 239Pu measurements on human excreta were made. An analysis of the tentative data leads to the conclusion that a reliable estimate of committed effective dose equivalent requires further research.
1946年6月至1958年8月期间，美国国防部和美国原子能委员会（AEC）在北马绍尔群岛进行了核武器试验。1954年3月1日，“城堡行动”系列中的一次地面试验“喝彩城堡”产生了大量放射性物质，由于风向意外改变，其中一些放射性物质随后落在了朗格拉普环礁和乌蒂里克环礁上。1954年3月3日，这些环礁的居民被撤离到受影响地区之外。他们后来于1954年6月返回乌蒂里克，1957年6月返回朗格拉普。20世纪50年代中期，布鲁克海文国家实验室启动了全面的环境和人员放射性监测计划，以确保受辐射的马绍尔群岛居民的体内负担保持在美国原子能委员会规定的范围内。文中呈现了他们的体内负担历史以及返回后的计算活动摄入量率模式，同时给出了内照射待积有效剂量当量的估计值。还包括外照射数据。此外，还建立了体内负担或尿活度浓度与持续摄入量下降之间的关系。这些研究的意义在于：（1）137Cs的饮食摄入量是环礁最初受污染后数年待积有效剂量当量的主要贡献因素；（2）对于饮食中包含鱼类的人来说，65Zn是返回后头几年待积有效剂量当量的主要组成部分；（3）估计137Cs、65Zn、90Sr和60Co的每日活动摄入量率下降幅度大于源放射性衰变导致的下降幅度；（4）每种核素对待积有效剂量当量估计值的相对影响取决于初始污染与恢复之间的时间间隔；（5）在恢复期，乌蒂里克的内照射待积有效剂量当量比外照射剂量当量高1.1倍，朗格拉普则高1.5倍。对人类排泄物进行的可靠的239Pu测量很少。对初步数据的分析得出结论，要可靠估计待积有效剂量当量还需要进一步研究。
