CHAPTER 3 SKIN LESIONS, EPILATION, 4‘ND NAIL PIGMENTATION 3.1 PREVIOUS FINDINGS The Rongelap and Ailinginae groups observed the fallout as a powdery material that fell for several hours and clung to their skin and hair. Thorough decontamination was not accomplished until evacuation occurred one to two days » Cay later. The dosage to the skin, resulting from soft beta and soft gamma radiation, could not be calculated due to the complex make-upof the fallout material. Initial symptomatology related to the skin consisted of burning and itching in a large numberof people, and irritation of the eyes with lacrimation in a small number, the first two days after exposure. The early symptoms were followed by pronounced lesions of the skin and epilation of the head, which first appeared about the 12th to the 14th day post-exposure in the Rongelap group and after the 20th day in the less-exposed Ailinginae group; the lesions occurred primarily on the exposed parts of the body which were not protected by clothing. Those persons who remained under shelter in their homes developed less severe lesions or no lesions. Also, there was some protection to those who bathed or remained in their homes during the fallout. The development of the skin lesions did not conform in all respects to beta skin lesions described in the literature. No primary or secondary erythema was observed; however, the dark skins of these people may have obscured this phenomenon. The lesions showeddifferences in the latent period and appeared on different parts of the body in roughly the following sequential order: scalp, neck, axillary region, antecubital fossae, feet, arms, legs, and trunk. Epilation and scalp and neck lesions were observed in 60 to 70 per cent of the Rongelap group, and foot lesions were also common. The first indication of a developing skin leston was the appearance of pigmented macules, papules, and raised plaques. Usually, these dark pigmented lesions had a dry, thickened, leath- ery feel. However, some areas developed only simple hyperpigmentation of the skin over extended areas. The majority of lesions were superficial without vesicle formation, which, after several days, showed dry, scaly desquamation of the pigmented skin from the center of the lesion outward. Desquamation left depigmented. pink-to-white epithelium not remarkedly dif- ferent in texture from the surrounding skin. During the next few weeks the lesions gradually became repigmented, resulting in a relatively normal appearance. Approximately 20 per cent of the Rongelap people developed lesions of a deeper nature, which occurred primarily on the feet, to some extent on the neck and scalp, and, in one case, on the ear. These lesions also nvegan with hyperpigmentation, followed in a few days by wet desquamation with weeping and crusting ulcer formation. In someof the foot lesions hullae formation occurred, followed by a breaking of the bullae with ulceration. Many of the lesions were accompanied by symptomsof pruritus and a burning sensation, and someof the deeper lesions were painful « uring the acute stage. The application of bland antipruritic lotions and 14