134 DASA 2019-2 CONARD: Figure 20 shows one of the boys with greatest growth retardation (on the right) standing beside his brother who is a year younger. Shortly after this picture was taken we started the boy on thyroid hormone treatment. Figure 21 shows the same stunted boy on the left before treatment and on the right a year later. ROOT: His features— the myxedema is gone. CONARD: Yes. He's changed in appearance. I hardly knew him when | saw him after treatment with the hormone. We'll go on then to the chronic exposure from residual fallout. I refer here to the period following the first few days of acute exposure. In this situation we have low dose rate whole-body irradiation, possibly some irradiation of the skin, and internal absorption of some radioactive isotopes. We know that chronic low dose exposure such as this will increase to some extent the incidence of leukemia and cancer of the skin and has becn seen by radiologists over the years. But we are in a region that we really know very little about in regard to human effects. We get down into the region in which there is controversy over whether or not there is a linear dose effect relationship and wnether or not there is a dose threshold for the effect. In the case of the Marshallese, at the time of their return to Rongelap Island there was a lowlevel contamination consisting mainly of the rzdioisotopes cesium-137, strontium-90 and zinc-65. Though the body burdens were well below the MPC levels, it has afforded us a unique opportunity to study th» radioecological situation in the Marshallese. Perhaps in your discussion tomorrow, Lauren, you might bring ina little bit more on this aspect of the thing. ‘DONALDSON: Yes. CONARD: I find it extremely difficult to visualize what the situation witl be during the aftermath of the atomic borab. I have tried to visualize the importance of residual fallout in this situation and I just can't give it too much emphasis. Tome, if one survives the acute fallout situation the economic, transportation, and psychosocial problems will far outweigh the residual fallout proLtem in importance.