12 examiners. However, even at the nadir of depression (platelets, 28 to 30 days; granulocytes, 42 to 46 days) no associated bleeding tendency or increase in infections was seen. Eleven individuals had platelet counts between 35,000 and 65,000 but without evidence of bleeding. Between days 23 and 42 post exposure, 10% of the Rongelap group developed granulocytopenia of < 1000cells and 42% had leukocyte counts < 4000 or absolute granulocyte counts < 2500. During this period an epidemic of upperrespiratory infections occurred involving more than half the exposed population. Theillness in the higher exposure Rongelap group was no more severe than in the less exposed groups, and individuals in all groups were able to show an upwardtrendin leukocytes during the illness. Prophylactic treatment with antibiotics was notinstituted because it was considered wiser to withhold them until a real need mightarise. Antibiotics were given in certain cases where such therapyis ordinarily indicated. 2. Effects of Skin Exposure Beta burnsof the skin are described in detail in the original report of the medical findings.? The fallout was ubiquitous on Rongelap, Ailingnae, and Rongetik. The gritty white flakes clung to the moist skin, got into the hair, were inhaled, and were ingested with contaminated food and water. Areas of the skin covered by clothing were largely protected, and some whobathedin the lagoon and children who wadedat the water’s edge unknowingly were protecting themselves since they werelater found to have fewer skin burns. However, the majority of the people on Rongelap and Ailingnae had widespread contamination ofexposed surfaces of the body; the skin dose was probably in the thousandsof rads and was due mostly | to the beta component. Most of the people complained of itching and burning of the skin for the first 24 to 48 hr, and some complainedalso of burning and lachrymation of the eyes. This may have been due partly to the caustic natureofthe fallout. These symptoms wereless evident in the American servicemen on Rongerik and were absent in the Utirik people. Table 6 shows the amountoffallout andtheresulting skin burns for different groups. Personnel decontamination commenced on board the Navy ships used for evacuation, where the people were given saltwater showers and clothing donated bythe crew. Onarrival at Kwajalein the skin was still contaminated, and decontami- nation procedures were continued for several days. Clothing was laundered repeatedly, and wasdis- cardedif its radiation level was not sufficientlyreduced. Thefirst skin burns appeared about 12 to 14 days post exposure in the Rongelap people; burns appeared somewhatlater in the Ailingnae and Rongerik groups and wereless severe and extensive. About 90% of the Rongelap and Ailingnae groups and 40% of the Rongerik groups developed lesions, but noneof the Utirik people. Thelesions were multiple and spotty (Figure 5) and were characterized by superficial hyperpigmented macules, patches, or raised plaques, which desquamated within a few days leaving thin, pink epithelium (Figure 6). No erythema was observed before or during developmentof the lesions: it may have been lacking because ofinsufficient dose to dermis, or it may have been obscured bvthe darkness of the skin. Deeper burns with ulceration were noted in about 15% of the Rongelap people. Epilation (Figure 7) usually accompanied scalp lesions and was prevalent in >90% of the exposed Rongelap children (Table 7); it occurred to less degrees in adults and Ailingnae groups. Lesions were most common on the anterior neck, axillae, antecubital fossae, and feet, but even the anal region in some young children was involved. Lesions of the dorsum ofthe feet (Figure 8) were Table 6 Skin Lesions? Group Rongelap Ailingnae Rongerik Unrik Composition 64 Marshallese 18 Marshallese 23 White Americans 5 Negro Americans 157 Marshallese Fallout observed Skin lesions and epilation Heavy (snowlike) Extensive None ’ None Moderate (mistlike) Moderate (mistlike) Less extensive Shght