-2If we assume a linear buildup of fallout from H + 6 to H + 18, t_ 1.2 decay during this interval, and use the reading of 375 mR/hour at 7 days, the estimated dose from fallout during cloud passage is 47 R. the fallout from H + 18 to evacuation at H + 51 is 114 R. The dose from Experience from Sedan indicates that the dose from the cloud itself is approximately equal to the dose from fallout during cloud passage. 47 +47 +114 = 208 R. The total estimated dose is then Within the error of the measurements and the accuracy of the assumptions, this estimate, which does not contain any correction for the small effect of time indoors, does not differ significantly from the value of 175 R.} We will, therefore, take the average whole-body gamma dose as 175 + 25 R. Internal Deposition of Iodine Isotopes Unfortunately, no direct measurement was possible on the radioactive iodine content of individuals from Rongelap. Urine samples were taken from which the average thyroid burden of isl has been estimated. The Los Alamos Scientific Laboratory collected pooled 24-hour samples 15 days post.-detonation and estimated” the 1-day thyroid content as 11.2 pCi of 1 131 USNRDL collected samples from each member of the exposed group 43 and 46 days post-detonation and, by an indirect method, estimated the average thyroid content as 6.4 pCi ysl at 1 day.?* 4 The LASL estimate of 11.2 uCi was obtained by direct counting of ys! in the urine and should be more reliable than the NRDL estimate. The value of 11.2 uwCi will be used as a basis for all following considerations. This estimate was based on the assumptionof 0.1% of the maximum thyroid burden being excreted in the urine on the 15th day. Variation in the biological half-life and other factors indicate that a range of 0.05 to 0.2% should be placed on this number® (see appendix). We, therefore, take 5.6 to 22.4 uwCi as the range of adult ie 31 thyroid burden. The pooled samples represent all age groups. The number of individuals in these age groups and the volume of urine from each age group is approximately as follows:*”