‘body burden means for edulte-on Utirik and the observed kerate:‘constant frou Rongelap. It was observed. on Rongelap that .031% of 65 diet pathway each day in addition to radioactive decay. “Zn was removed from the Additionally, reduction in dietary radioactivity on Rongelap had been observed tor )?"cs, 905, and 0065 to be greater than that predicted by radioactive decay sjone Instantaneous re- phat duction fractions very:simikee. to, those,abpongel ap”were)‘observed st Utirik for the 90 Sr, and 137 G4 nuclides. The lower curve on Figure 16: reflects the dose equivalent, dose equivalent rate, and body burden which yould have occurred liad y radioactive decay alone aceounted:iforithe removal of *°Zn from the Utirik environment. Since additionalimechanisms could be measured for other nuclides at BAQIV Mad po jlae Utirik and for the °2n nuclide o on a nearby sto]1,°*the upper,curve was chosen as the most likely body burden history for adults post return c Utirik Atoll. Figure 17 indicates the Utirik adult mean total body dose equivalent rate for each nuclide. An obvious difference relativeto the Rongelap history exists} 6508 not 1370, was the major nuclide contributing to the dose equivalent rate. This was due to the Utirik population returning 3 to 4 months after the initial contaminating event, and the Rongelap population returning after 3 The age of the fallout had a dramatic influence on the importance of each nuclide contributing to the internal dose equivalent. In fact 60., ani 6975 played major roles during the first 3 years, a time intervel that corresponded to the period during which field whole body counting facilities were being developed at Brookhaven National Laboratory and when medical exaiu!naAdditionally, pooled and/uy in- ve * ik + ve a vie er dividual radiochemical analysis of urine was not performed during this periad. . The impact of 65 . . °~Zn and 606, was such that even if the least conservative rate 34 7% me ‘ ee sae ~gee or i oe eS ie eegee pea rig pe . : o on tions for people on Utirik Atoll were not done, , a wet . ah - He Ret gat a rt 5, Lass ae thas eX LUtm Ur a ae S: ™ are? Rasn. pat #,be. Toole’ + sr cate we ee Se years,