-. ,.’. 4.3 Internal Dose - Brookhaven National Laboratory Brookhaven chose the method of uhole-body counting to follow cesium in the exposed population, supplemented by urinary analysis to determine strontium and plutonium-239 (Conard et al, 1980; Lessard et al 1984b~ 1984c; Miltenberger et al 1980). The method is the definitive one for cesium, since it is a direct measure of nhat is wanted and it is independent af assumptions regarding the diet and other external factors. It is of primary importance for the present case, since cesium accounts for some 80% of the internal whole-body dose. The Brookhaven results in Fig. 4.3 #l show the decline in cesium-137 body burden from about 670,000 picocuries in 1958-65 (.11 rem/year) to Thus the Brookhaven about 175,000 picocuries in 1979 (.03 rem/year). cesium internal dose-rate of .030 rem/year (whole-body) in 1978 was only 33% of that by the dietary input method (.094 rem/year). The 30-year cesium whole-body dose was .624 rem. The tissue doses to bone surfaces, red marrow, liver, etc. would be equal to this figure. .... / ~ diet y.ith-gr+at= exposure (type B), which DOE-198 * ! @.uv-. overestimate of cesium dose by a factor of three compared result “ a m“ to whole-body counting. The most likely source of the discrepancy would be the diet--the use of the type B diet. Robison (1983) has reported evidence that this could be so. If the HLSC diet (imports available) were employed (Note 11, Table 1), the cesium body content calculated from the imput data (.19 microcuries) would be in approximate agreement for 1978 with that measured by whole-body counting (.17 microcuries). (Do Lessard and Robison agree to this statement?) We do not have an independent field check on the accuracy of the whole-body field measurements. The point nay be made, however, that it was this team that discovered the precipitous rise in body-burden of the Bikini settlers in 1977-78 and who therefore called for their removal from Bikini Atoll (Conard et al, 1980; Hiltenberger et a~~ 1980)= In the case of strontium, ue shall take the 1980 findings at face value (see Note 8). In the BNL 26-year report, 3 autopsies confirmed the urine analysis (Conard et al, 1980, p. 115). The annual whole-body dose based on urine analysis was about .001 rent from which I calculate a 3Q-year dose of .021 rem. The corresponding tissue doses are: red marrow .11 rem; bone surfaces, .25 rem. -