piatelets which preventbleeding. With large amounts of radiation, such depression may lead to death from infection and bleeding. Therefore. numerous examinations of the blood were carried out during the six weeks of examinations. Increasingly severe depression of the white blood ceils (lymphocytes) and platelets was noted duringthe first few weeks, failing to about one-half to one-fourth normal levels. The greatest drop occurredin the children. This depression was muchless in the Rongelap people who had been on Ailingnae and the Americans who had been on Rongerik. The people of Utirik, who had received a much smaller radiation exposure, showed only slight depression of the average platelet count. By six weeks, when the initial examinations were concluded, the blood elements in the Rongelap group showed recovery approaching, but not reaching, normal leveis. Beginning about 10 days after exposure. radiation burns of the skin began appearing in the Rongelap people. These so-called “beta burns” appeared as dark pigmented spots on the scalp and on parts of the body that had not been covered by clothing.® The top layer of skin of these spots then peeled away,leaving depigmented areas: somelesions later became ulcer- ated. The majority of the Rongelap children had these burns. The burns were muchless pronounced in the Ailingnae graup andthe . American servicemen. Nobeta burns.were . noted in the Utirik group, Loseofhairweaasao- ciated with the scalp burns. The burns were accompanied by itching and burning! sensations. and some of the lesionsoa thetop ofthe; fees. were painful, particularly during walking. . Biopsies of the lesions showed severe injury to the skin surface, butlittle injury to the deeper tissues, showing that the effects of the beta radiation were superficial. After two to three. weeks, the beta burns began healing, with repigmentation and regrowth ofhair. Except for the changes in the skin and blood, the exposed people appeared to be generally in good health, and there were no differences between the more exposed groups © compared with the lesser exposed groups. Some slight weight loss was noted in the Rongelap people, which may have been related to the change of environmentand diet. “The term ‘beta burn’is used. since injury to the skin was largely from beta radiation in the fallout. SO0u 159 sath imesh i hens “Lhe Extensiveradiationhurnsin a rounsRowse boy. At the outset, the |medical team had no way of estimatingthe wholebody dosa.received by people. In accordance with good,medical procedure, we decided that the clinical findings, particularly the degree of depression of blood elements, would be the index used to estimate the seriousness of the effects of the exposure. Animal studies had shown that such a “biologi- cal dosimeter” was valid. This decision proved to be a good one. The doses estimated Jater agreed well with the clinical findings that might be expected, based on animal studies. During thefirst few weeks when the blood counts were dropping and numerous skin burns were appearing, serious consideration was given to the possibility that further medical assistance, such as the use of a hospital ship, might be necessary. Admiral} Bartholomew Hogan, the Pacific Fleet Surgeon of the Navy at Hawaii, said that naval assistance would be available (B-12).