} Sr? Ball’ Fisstonable matertal o? 1.6 yc 2.7 ye negative Based on the Sr® analysis, the Hunter-Ballou fission data® and the retention data of Hamilton," the following estimates of skeletal body burden in the Rongelap group on diy t were made: a) rare earth group - 1.2 uc b) I'' — 6.4 me The integrated dose to the thyroid from I'*' and the shorter lived iodine isotopes (1!8?, 13) and 1’) assuming a 20 per cent uptake, 24 hours was 180 rep. The Ailinginae values were then approximately one-half and the American were one-fourth of these values. On the basis of a radiochemical analysis on pooled urine samples collected from a cross section of the Rongelap and American populations, 16~18 March, Los Alamos reported™ the following estimate of fissions associated with material inhaled and: or ingested by the Rongelap native group: 1! — 5.5 x 10!) fissions Sr® — 1.2 x 10" fissions Ba'** _ 1.0 x 10" fissions From these data, using certain assumptions as to the uptake and retention of these radivelements by the body, the following estimate of body burden at one day was derived: Rongelap (uc) sr*? 2.2 Bae Rul American (uc) 042 Ca‘é 0.34~ 0.013 0.19 0.27 0.015 I'S! and short lived 5.1 mc 1.9 mc Fissionable material 0.016 ugm I'S! equivalents 7 0,04 The initial body burden of I'* and short lived iodine isotopes, energetically equivalent to I'3! ig 5.1 mc. The estimated total integrated dose to the thyroid from the iodine isotopes assuming 2 20 per cent uptake/24 hours and with corrections for decay of the very short lived iaotopes was calculated to be 150 rep for the Rongelap natives and 50 rep for the Americans. It can be seen that with widely different approaches to the estimation of the body burden, the results obtained are very similar with the exception of the Ba'® estimate. An attempt to detect bone-fixed radioactive emitters by means of sensitive film badges taped below the knee over the epiphysis of the tibia on 40 exposed Marshallese yielded negative results. 5.4.3 Internal Radioactive Decontamination Ethylene diamine tetracetic acid (EDTA) has been shownto be the most effective chemical agent to date for mobilizing fission products from the skeleton and for increasing their excretion rate. "8.8 This chelating agent was therefore used in a decontamination therapy attempt on a group of seven Rongelap individuals having relatively large amounts of internally deposited radioelements. Oral administration of caicium EDTA, 1 gm, 25 lb body weight daily 95 eeerte w to the exponent found in the huflaly rfdithydita Ul Norrid®™ “unl Ledney 6 Using his formution the individual skeletal body burdens extrapolated back to day one are as follows: Pa ANYMigs pata? ———— seen he | I