for individual members of the general public. The highest individual adult committed effective dose equivalent (Moses ID #1180) was estimated to be 1.4x10-3 Sv (140 mrem) during the calendar year 1982. The validity of the Pu-239,240 data used to estimate the body burden at Rongelap Atoll in 1973 had been considered previously by an ad hoc committee of the Energy Research and Development Agency. The committee concluded that, because of the possibili~ of contamination of the urine and fecal samples, the data were uncertain. To determine the extent of sample contamination and to estimate a background level of Pu in these samples, urine and fecal samples were collected during the July 1982 field trip from two groups of persons not living on contaminated atolls. The former Bikinians provided ssmples for these studies as did some current residents of Majuro Atoll. Collections at Rongelap will provide an estimate of body burden during 1981 and 1982 and allow assessment of the effective dose equivalent since rehabitation of the atoll in 1957. The long mean residence time of Pu-239,240 in the body will allow for assessment of effective dose equivalent to the former Bikini residents while living at Bikini Atoll based on the analysis of recently collected samples. The CS-137 body burden of the former Bikini Atoll residents is now statistically indistinguishable from the comparison population values obtained at Majuro Atoll (see Table Two). The fomaer Bikini residents have the lowest CS-137 population body burden (see Craph Two) out of the four atoll populations currently under study. The increasing CS-137 body burdens at Rongelap, Utirik and Enewetak imply that local phenomena infltinced the elevation of CS-137 in the diet. The observed decline in the former Bikinian body burdens was anticipated based on the value for the long-term biological turnover rate constant for CS-137. 4