Order number 940330-160606-96 set 11 with 111 of page 2 -001-001 111 items EXPOSURE; PLUTONIUM; PUBLIC HEALTH; RADIUM; RADON; RUSSIAN FEDERATION; THORIUM 232; THOROTRAST;WORKING CONDITIONS EDB Item 2 f UCRL-JC--115100 A dose assessment for a U.S. nuclear test site -TITLE ENGLISH Bikini Atoll PERSONAL AUTHOR/AFFIL Robison, W.L.; Bogen, K.T.; Conrado, C.L. PRIMARY REPORT NUMBER CORPORATE TEXT PUB. DATE (YYMMDD) LIMITATION CODE ABSTRACT Lawrence Livermore National Lab., 930700 UNL On March 1, 1954, CA (United States) a nuclear weapon test, code-named BRAVO, conducted at Bikini Atoll in the northern Marshall Islands contaminated the major residence island. Here the authors 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. The unique composition of coral soil greatly alters the relative contribution of cesium-137 and strontium-90 to the total estimated dose relative to expectations based on North American and European soils. Cesium-137 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 estimated maximum annual effective dose is 4.4 mSv y{sup {minus}1} when imported foods, which are now an established part of the diet, are available. The 30-, 50-, and 70-y integral effective doses are 10 cSv, 14 cSv, and 16 cSv, respectively. An analysis of interindividual variability in 0- to 30-y expected integral dose indicates that 95% of Bikini residents would have expected doses within a factor of 3.4 above and 4.8 below the population-average value. A corresponding uncertainty analysis showed that after about 5 y of residence, the 95% confidence limits on population-average dose would be {+-}35% of its expected value. The authors have evaluated various countermeasures to reduce {sup 137}Cs in food crops. Treatment with potassium reduces the uptake of {sup 137}Cs into food crops, and therefore the imgestion dose, to less than 10% of pretreatment levels and has essentially no negative environmental consequences. BIKINI/fallout ;MAN/radiation doses ;FOOD CHAINS/contamination ;CESIUM 137/uptake ; STRONTIUM KEYWORDS 90/uptake ; BIKINI; FALLOUT; EXPERIMENTAL DATA; MAN; CONTAMINATION; UPTAKE I00343b