2 EYTECTS OF JONTIEING RADIATION | were abssat until the visible lesions developed. Dering the early stages of development of the lesions, itching, burning and slight pain were experienced with the more superficial lesions. With deeper lesions pain was more severe. The deeper foot lesions were the most painful and cansed some of the people to walk on their heole fer several days during the acute stages. Mome of the more severe lesions of the neck and axilla were painful when turning the head or raising the arms. The lesions did not produce any constitutional symptoma. 3.3 3.31 Gros Appearence The time of appearance and the severity of the lesions varied with the degree of skin contamination in the different groups. The Ronge- lap group, which showed greatest radicective contamination of the skin (according to instru- ment readings) were the first to develop lesions and epilation at about 12 to 14 days after the accident. They also had the st severe jesions. Skin lesions in the lesser exposed Ailinginse and Rongerik groups developed approximately one week after {hose in the Rongelap group, and The Utirik group did not develop any lesions which could be attributed to irradiation of the skin. The incidence of ulcerating lesions in the different groupe reflected the relative severity of the skin injury. Twenty percent of the Rongelap people developed ulcerative lesions while only five percent of the Ailinginae and none of the Rongerik people developed ulcerative lesions. Ninety percent of the Rongelap and Ailinginae groups developed jesions, compared to only forty per- cent of the Rongerik group. There were more lesions per individual in the Rongelap group than in the Ailinginae or Rongerik groups. A comparison of the incidence and time of appear- ance of epilation and neck lesions in the two gToups is illustrated graphically in Figure 3.1. * The description of lesions refera tu the Warnhallese unless otherwise indicated. ee a ered by clothing during the fallout. The majority of individuals developed mektiple lesions (particularly the Rongelap growp), most of which were superficial. There was 2 difference of several days in the latent period before development of lesions on various akin arves. The order of appearance was roughly 20 follows: scalp (with epilation), neck, axillary region, antecubital fosse, feet. arms, legs, aad trunk. Lesions on the flexor surfaces in general preceded those on the extensor surfaces. Tables 3.1 and 3.2 show incidence according to age and Description of Skin Lesions* were leas severe and extensive. Nearly all of the lesions were spotty and de- veloped on exposed parts of the body not cov- time of appearance of lesions in the various groups. In the early stages al] lesions were characterised by hyperpigmented macuies, papules, or raised plaques. (Plate 1.) These frequently were snall, 1-2 mm. areas at first, but tended to coalesce in a few days into larger lesions, with a dry, leathery texture. The pigmented stage of the superficial lemons within several days was followed by dry, scaly desquamation which proceeded from the center part of the lesion outward, leaving a pink to white thinned epithelium. As the desquamation proceeded outward, a characteristic ap- pearance of a central depigmented area fringed with an irregular hyperpigmented sone was seen (Plates 2 and 3). Repigmentation began in the central area and spread outward over the next few weeks leaving skin of relatively nor- mal appearance. Plates 3, 4, 11, and 12 show superticial lesions as they appeared initially and six months later. The mildest manifestation of akin injury was the development of a blotchy increased pigmentation of the skin with barely perceptible deaquamation. Such lesions were most often noted on the face and trunk. Epilation was usually accompanied by scalp lesions (Plates 13, 17 and 19). Some indi- viduals developed new scalp lesions cver a period of about a month. Neck lesions usually had a “necklace” distribution, beginning anteriorly and spreading posteriorly. These were more severe in women in whom thick hair

Select target paragraph3