FALLOUT EFFECTS—CONARD & HICKING 459 autopsy or biopsy. One unexposed older woman died possibly of cancer of the cervix, but the diagnosis was not confirmed. The question of increased incidence of malignancy in the irradiated Marshallese must be left open for the present. Beta Radiation Burns.—During the past several years an increased number of pigmented nevuslike lesions have been noted in previously irradiated areas of the skin but these have appeared to 4. Development of pigmented nevus-like lesions in area of neck previously involved with beta radiation burns. Most pathologists consulted did not feel that radiation could be implicated as the etiologic agent on the basis of the pathological findings alone, though some considered the findings typical of the lesions seen in children treated medically with radioactive iodine. However, the evidence is strong that the thyroid nodules in the Marshallese girls were induced by radiation. Correlation of the thyroid with radiation exposure was substantiated by statistical analysis which showed the difference in thyroid nodule incidence between the exposed and the unexposed children to be significant at the 1% level. Moreover, Sheline et al® and Lindsay and Chaikoff* have reported the development of thyroid nodules 5 to 11 years after treatment of children with radioiodine for thyrotoxicosis. Lindsay and Chaikoff reported that the sections of the glands removed from the Marshallese girls were similar to the glands of children who had been given *'!l therapy. Based on a calculated dose of approximately 150 rads’ to the adult thyroids from isotopes of iodine, it was estimated that the smaller thyroid glands of the girls exposed at three to four years of age received a total dose of the order of 1,000 rads (probable range was 700 to 1,400 rads). The fact that a part of the total dose to the thyroid (175 rads) was due to whole body gamma exposure (including the pituitary gland) may be of some significance. In the Marshallese girls the stress of puberty may have been a factor in the development of the nodules. Malignancy.—No cases of leukemia in either the exposed or unexposed Rongelapese have been detected. Two older exposed women died with a diagnosis of cancer, one at 67 years of age from ovarian malignancy five years after exposure, and the other died at 60 years of age, eight years after exposure, probably from cancer of the cervix. The diagnosis in the latter case was not confirmed by 2k Ba ~ "© “' * y© 2i + ,No6 JAMA, May 10, 1965 @ Vol192 be quite benign (see Fig 4). Neither chronic radiation dermatitis nor evidence of cancer of the skin has been noted. Internally Absorbed Isotopes.—Radiochemical urine analyses and whole body spectrometric analyses revealed that the body burdens of radioisotopes in the exposed Rongelap people fell rapidly, so that by two years after exposure the levels were far below the stated maximum permissible levels. The return of the Rongelap people to their home island was associated with a rise of their body burdens of '’Cs and “Zn and “Sr. However, by 1961 the whole body content of ‘Cs had apparently reached an equilibrium with the envi- ronment at about 14.7 myc per kilogram of body weight and the “Zn had fallen to low values. The levels of °’Sr by 1964 showed a slight decline over previous levels to about 10 to 12 myc for adults and 20 muc for children (about 5% and 10% respectively of the maximum permissible level for members of the population at large). The possible relation of internal absorption of radioiodines in the fallout initially to the recent development of thyroid nodules was referred to before. No other effects of such exposure have been detected. It should be noted that the 11th year examination, currently in progress (March 1965), has turned up three more cases of thyroid nodules in exposed people, one in an adult. The type and character of the nodules have not yet been determined. This investigation was supported in part by the US Atomic Energy Commission and the Trust Territory of the Pacific Islands. Capt C. A. Broaddus, MC, USN, performed the surgery. Sections of tissues were reviewed and reported on by S. Warren, MD, G. H. Klink, MD, C. J. Stahl, MD, H. A. Johnson, MD,and S. Lindsay. MD. Kieth Thompson carried out the chi-square test, and Ralph James and John Gofman, MD,calculated the thyroid dose to the children. References 1. Cronkite, E.P., et al: Effects of Ionizing Radiation on Human Beings. Report on Marshallese and Americans Accidentally Exposed to Radiation From Fallout and Discussion of Radiation Injury in Human Being, US Government Printing Office, 1956, Pp 1-106. 2. Conard, R.A., et al: Medical Survey of Rongelap People Eight Years After Exposure to Fallout, Brookhaven National Laboratory Report 780 (T-296), (Jan) 1963, pp 1-74. 3. Conard, R.A.: Attempt to Quantify Some Clinical Criteria of Aging, J Gerontology 15:358-365, 1960. 4. Sutow, W.W.; Conard, R.A.; and Griffith, K.M.: Growth Studies of Children Exposed to Fallout Radiation in Marshall Islands, Pediatrics, to be published. 5, Sheline, G.E., et al: Thyroid Nodules Occurring Later After Treatment of Thyrotoxicosis With Radioicdine, J Clin Endocr 22:8-18 (Jan) 1962. 6. Lindsay, S., and Chaikoff, LL* Effects of Irradiation on Thyroid Gland With Particular Reference to Induction of Thyroid Neoplasias: Review, Cancer Res 24:1099-1107, 1962.