Rite - A ae AAme, Fltee ee 136 DASA 2019-2 UPTON: Could lask, Bob, about the dose rate at the time they were evacuated? Suppose it had been impossible to get them out promptly? Suppose one had waited a few days or a few weeks, would the situation have been vastly different in the outcome? CONARD: There wouldn't have been as much difference as you might think. The total dose would have been, say, around several hundred rads, around £50 I believeit was, if they had stayed on there. DUNHAM: And never left at all? CONARD: Yes. ROOT: Is it because of the short half-life of most of the elements that there would have been no appreciable increase with time? CONARD: It's due to the fact that the shorter-life elements are dying out and only the longer-life ones are left, so that the radiation dose rate reduces with time and the dose rate would have been cansiderably less as time went on. ROOT: Like, for instance, if you have strontium-90, docs the body take up as much as it can in tne initial stages so the residual strontium90 doesn't have much effect? CONARD: You do reach a point of equilibrium with the environment, that is provided the dietary source of strontium-90 remains constant, UPTON: But the total dose wouldn't have been twice what it was had they remained indefinitely on the island? CONARD: No, not the whole-body dose. TAYLOR: Is that independent of strontium-90 concentration in the food that they eat? I thought that that didn't really come up. CONARD: Inthe Marshallese the majority of the present body bur- den of strontium-90 is from their native dietary source after moving back to the island. ‘ AYRES: In the first few days the concentration of strontium-90 would have been very, very tiny, whereas ten years later it would have been a significant fraction of what was left.