hyperpigmentation, The macules and papules (t (6°2 mn in daameter) usualy cecurted tn clusters and sometimes coalesced into larger lesions. The latter were characteristically found on the sealp, neck, and the antecubital fossae. The raised plaques varied inoatve Crom a few niilimeters lo several centimeters in diameter, were (ick, rough, dry, and hada leathery feel. ‘This type of lesion oceurred predominantly on Che feet and to the antecubital fossae aad todomuch lesser extention the neck. Areas of mereised pocmentation sisa ceeacred on the links, (runk, and on the face. , The majority of Qe lesions were guperficnl without blisters. A few days affer appearance, Decurred in the central portion of the hyperpigniented areis. Phe des dry, scaly desquundl quanmiition fetta pink fo white epithelium not remarkably different im texture from the surFable G21 BSIONS IN RONGELAP GROUP Per Cent of Total lo Age Group haviag Indfeated Lesion Type of Lesion Median Vie oman ite of First Age O95 Clo people) Age G-15 Ch peopte) Age 16 & Over (38 people) ‘Total Geoug (64 peopled Observation of Lestons* I plas 2 plus 7.6 38.6 38.4 30.7 es Pra) 5.0 17.2 17.2 17 17 % plus 54.8 23.0 8.8 22.0 Jo 10,0 92. | 27.6 56.2 ah 7 Bpilation Total Skin baestotes wu.4 0.0 ato 7.8 Seabp Anus-Groin 1OQ.0 LOO,0 37.0 6Q0 tH Neck GOW’ 76.9 GbL0 70,3 wt Axttla Gt 76 7 24 Zi Antecubital L7 38.4 34.2 34.4 Hands-Wrests Fossac ~ $0.7 23.0 1k,4 21.0 oo Feet Arms 23.0 15.3 53.8 15.3 53.0 LO.8 45.5 12.5 28 St Legs Trunk Nail Pigmentation ct 28 TG 23.0 4.5 7. aa 13.3 23.0 4.3 94 BH 61.5 100.0 95.0 89.0 3H * Post-exposure davs. rounding skin. As the desquamation proceeded outward, the areas developed a characteristic appearance of a ventral depigmented area fringed with a hyperptgmented zone. Ala later stage, pigmentation began in the central areas and spread outwards. After a few weeks the cycle was completed, leaving in must instances a relatively normal appearing skin. Approximately 20 per cent of the Rongelap group developed lesions which were mure severe, These lesions might be considered as compariuble to second degree Checaual burns. Phe deeper lesions occurred principally on the feet and to a lesser extent on the seaip and neck and Inone case onthe ear. Btister formation was not common. However, on the feet, some large bullae (blisters) appeared. After a few days, the hyperpigmented lesions showed wet desquamiation with weeping and crusting, leaving depigmented raw surfaces of varying area. Someof these lesions became secondarily infected. Epithelium rapidly covered the ulcerated areas within a week tu 10 days. Pigmentation followed during the next few weeks. As healing occur- red many of the more severe lesions (particularily on the neck and antecubital fossae) developed a thickening of the skin with an “orange peel” appearance and a dusky, grayish-brown color (see Plate 3.4).