ointments was the only treatment necessary, except in a few lesions which became secondarily
infected and which were treated with antibiotic ointments.
Essentially, all lesions healed rapidly and re-epithelialized in a week or 10 days. Repigmentation gradually took place in most of the lesions, and in some, notably on the neck, hyperpigmentation of a grayish, dusky color developed with thickening, resulting in an “orangepeel” appearance. The deeper foot lesions, however, did not show repigmentation.
An unexpected finding in nearly all the Rongelap and Ailinginae people was the development
of a bluish-brown semicircular band of pigmentation of the fingernails and toenails which was
first noted about the 23rd day. The pigmentation band started in the semilunar area and progressed distally with growth of the nail. Since all the American Negroes but noneof the white
Americans exposed developed this pigmentation, it appeared that this phenomenon was charac-
teristic of dark skinned races. It also was probably due to whole-body irradiation and not local
skin irradiation, since some individuals without skin lesions developed the pigmentation and
vice versa.
Biopsies taken from active lesions showed spotty transepidermal damage with atrophy and
flattening of the retepegs. Areas of relatively normal skin intervened, emphasizing the particulate nature of the radioactive material. Celis of the malpighian layer showed pleomorphic nuclei, pyknosis, and cytoplasmic halos. Focal disorganization of the malpighian and basal layers
was present in extensively damaged areas, In the dermis, telangiectatic vessels were noted in
areas where the overlying epidermis showed greatest damage, and there was considerable
lymphocytic infiltration surrounding these telangiectatic spaces. An outstanding feature of the
early histological changes was the pronounced damageto the epithelium, with relatively minimal damage in the dermis.
Biopsies taken at six weeks post-exposure showed, in general, that the epidermis had made
a definite recovery, except for a few persistent areas of atrophy and finger-like downgrowths
of stratum malpighii, with cells showing rather prominent pigment content. There were many
outward epidermal excrescences covered by thickened stratum corneum. The dermis showed
less cellular infiltration of the papillary layer but still some slight degree of telangiectasis of
the capillaries.
3.2
PROCEDURES
In addition to an examination of the skin and its appendages of the exposed people, 80 control Marshallese living on Majuro Atoll were also examined. Color pictures were taken of the
skin where indicated, and attempts were madeto take pictures of lesions magnified 20 times.
Biopsies were taken at the site of former lesions in 12 exposed individuals. Most were repeat
biopsies from individuals who had been studied in this manner duringthe initial examinations.
Several skin biopsies from control individuals were also taken.
3.3.
PRESENT FINDINGS
Healing of all the early superficial lesions was essentially complete. The skin had repigmented to normal color, appeared to be of normal texture, and gave no remaining gross evi-
dence of previous injury. Plates 1, 2, 8, and 9 show the early lesions as compared with their
appearance at 6 months. Those lesions which had been deeper, and particularly those which
showed evidence of transepidermal injury, continued to show slight evidence of previous dam-
age, largely in the form of pigment alterations. Most of the neck lesions, which at 10 to 11
weeks after exposure had shown the thickened skin with grayish, dusky pigmentation, showed
much less thickening and less marked pigmentation at 6 months. It was observed that the skin
of the necks of many of the control population, particularly of the women, showedslightly increased pigmentation. Hence it was frequently difficult to determine whether there was remain-
ing hyperpigmentation in this area or whether the degree of pigmentation was in the normal
range. There were, however, 10 cases out of an original 16 in which the amount of pigmenta-
15