seo ~ eo eree ee sp eee ee = -8- : 5 : oo™ thyroidism in two of the most retarded boys who had atrophic glands but no nodules, and a positive growth response to thyroid hormone therapy. Their protein bound iodine levels were below 2 pg percent. Two other children with thyroid nodules showed low values also. ' The radiation etiology of these thyroid lesions appears to be reason- ably certain in view of the following facts. (1) The thyroid glands received a substantial dose of radiation from radiofodines and external gamma radiation, (2) Only a few older people in the unexposed or low exposure groups have shown any nodules of the thyroid gland. (3) The diet is not lacking in iodine and there are no known goitrogenic foods. 9. Atomic Bomb Casualty Commission -- Adults The Atomic Bomb Casualty Commission has reported 14 cases of thyroid cancer among survivors less than 1400 meters from the hypocenter; 12 were found in the Hiroshima group, 2 in the Nagasaki group. These survivors had received external radiation; radioactive iodine probably was not a contributory factor. The frequency of thyroid cancer appears greater in the Japanese population than in the United States. The estimates of thyroid cancer range from 4.7 percent among all cases of thyroid disease in Japanese hospitals 11 3.1 percent in a study made at the Kyoto University Medical School, +* to 13 percent at the University of Hiroshima, 13 Socolow!4 points out that although the over-all incidence of thyroid cancer may not differ greatly among the atomic bomb survivors the age incidence does differ. Eight of his 21 cases were under 35 years of age whereas at Kyotol2 85 percent of the cases were diagnosed after the age of 40. Three of Socolow's cases at Hiroshima were between 3000 and 3500 meters from the hypocenter. These probably received little or no radia- tion on the basis of the most recent recalculations of dose.!° The estimates of doses given by Socolow for his cases range from 33 rads to 2620 rads. Seven of the thyroid cancers found in the two cities developed in persons under 20 years of age at the time of the atomic bombing. The estimated thyroid dose received by them ranged from 256 to 2620 rads. Leano, S., Konoe, K., and Iokawa, N.: Japan. Statistics on thyroid diseases in Nihon Naibunpi Gakkai Zasshi 34 (3):230, 1958. l2viyake, T., Torizuka, K., and Kusakabe, T.: disease in Japan. Epidemiology of thyroid Shindan to Tiryo 50:783-796, 1962. 13xusumoki, N., Aoki, M., Nakagawa, S., and Masuda, T.: thyroid gland. Diseases of Hiroshima Igaku Gencho 7 (6):1461-1467, June 1959. 14socolow, E. L., Hashizume, A., Neriishi, S., and Niitani, R.: Thyroid carcinoma in man after exposure to ionizing radiation. A summary of the findings in Hiroshima and Nagasaki. New England J. Med. 268:406- 410, February 21, 1963 loauxier, J. A., Cheka, J. S., Haywood, F. F., Jones, T. D., Thorngate, J. H.: Free-field radiation-dose distributions from the Hiroshima and Nagasaki bombings. Health Physics 12:425-429, March 1966. POE ARCHIVES fo