Mean Body Burden of Cs-137 ' WA CONN FW PF ON OANA ty \O ~ Year 196 —— United States Body Burden 280 1000 2000 | . “ picocuries ‘ OO 5100 64.00 | 8000 6700 4.600 6000 ce 11000 19000 16000 9700 5700 3500 Date from Gustafson and Miller, Health Physics 16, 167-83 (1969) rene As in the case of strontium-90, Cs-137 did not exist in the environment in 1944, No measurements are available for 1951. . The variability with geographic location is similar to that for fallout in general and a factor of 2 would cover most areas. An exception is the small group of Eskimos living off a diet high in reindeer méat. Their body burdens are 50 to 100 times higher than the ones shown in the table. This is caused by the peculiar food chain of lichen-reindeer-man which transfers cesium-137 with great efficiency. It is of interest to note that lead-210, which repre- sents natural fallout, is also concentrated in these individuals. The body burdens of cesium-137 in children are uniformly less than adults in the same area due in part to the half-time of retention.