WwW The herbivore are obviously the test concentraters, - DONALDSON: e4y of what you get from the whole-body count, showing the com- nw ~ o parsion of 1957 and 1959. CONARD: The next slide I think shows a srectograph In March, 1957, shortly after they had come back Showing an increase, the first peak being otk We carried out these whole-body counts over the years since they've been Dn cesium-137 and the second peak is zinc-65, back on the Island and I can now review very briefly what's 19 happened in the way of the body burden of these isotopes. il The next slide, please, This®is a histogram that 12 Shows the changes over the years, 13 Shows the higher levels, of course, connected. with the initial The first 1954 data there # 14 contamination.and then up until 1957 their body burdens re- 15 - duce practically to zero and then you see on their return to 16 Rongelap the increase in cesium and zinc and strontium-90, 17 of course ,also began to appear, and this had to be detected 18 not by whole-body counting but by urinalyses, radiochemical 19 analyses of the urine. 20 The levels reached a peak about 1961 or so andbe- el yond that time they have seemed to be at equilibrium with the 22 environnental levels of the isotope, 23 peaked at about a little less than one microcurie of body 24 burden, which is not high, but it represents @2bout 300 times 25 the level of those of us in the medical team that were counted. 26 Since that time it seems to have remained fairly constant, aT In other words, they are taking in just about as much as they 28 are putting out, 29 Cesium, for instance, In regard to the zinc, it reached a peak at about the 39 same time that the cesium did but suddenly within one year's 31 time it dropped to about 1/10 the previous year's value, and 32 I wonder, Lauren, do you have any comment on that as to why 33 we had this sudden drop in zinc~-65 in the people? Was Stafford Warren DOE/UCLA ¢D