Late Effects of Radioactive Iodine in Fallout Combined Clinical Staff Conference at the National Institutes of Health Moderator: Jacos Rosains, M.D., Bethesda, Maryland. Discussants: JosepH E. Ratt, M.D., PH.D., Bethesda, Maryland, and Rosert A, CONARD, M.D., Upton, New York Dr. Robert A. Conard of the Brookhaven Dr. Conard will describe the findings as they have developed over the ensuing 12 years. He was a memberof the original expedition dispatched by the Atomic Energy Commission and the U. S. Navy and thus can give us a firsthand report of theinitial radiation effects. The major emphasis of this Conference, however, will be on the late effects that have become evident only in the last several years. These observations highlight a subject that is currently of considerable theoretical and practical importance—the effects of radiation on the thyroid gland. The Conference will be opened by Dr. Joseph E. Rall, Director of Intramural Re- ers, both exposed and unexposed, have been Metabolic Diseases, who has participated rather unusual sort of fallout. In addition to body surface irradiation that led to skin burns and general body irradiation from the surroundings that led to acute radiation sickness, contamination of food and drink with radioactive isotopes of iodine pro- duced pathological alterations of the thyroid gland. Largely through the perseverance of National Laboratory, the Marshall Island- the subjects of thorough, repetitive examinations by teams of observers sent by the Atomic Energy Commission. Received March 27, 1967; accepted for publica- tion March 31, 1967. This is an edited transcription of a combined search, National Institute of Arthritis and In several of the previous expeditions to the Marshall Islands and who just returned. with Dr. Conard a few weeks ago from the latest visit. Dr. Rall will discuss the general a problem of radioactive iodine in fallout f from nuclear explosions. clinical staff conference at the Clinical Center, Be- RapioactTive Iodine IN FALLOUT eae Nuctear Expiosions 4 thesda, Md., by the National Institute of Arthritis and Metabolic Discases, National Institutes of Health, Public Health Service, U. 5. Department of Health, Education, and Welfare. Requests for reprints should be addressed to Jacob Robbins, M.D., Chief, Clinical Endocrinology Branch, National Institute of Arthritis and Meta- bolic Diseases, Bldg. 10, Rm. 8-N-315, National In- stitutes of Heaith, Bethesda, Md. 20014. Dr. JoserH E. Rati: The heat gene by a moderate-sized fission explosion erally results in a temperature of the of 10 million K. The complexity of . problemsassociated with fallout generated 1214 JUL Zé ho wer R, JAcoB Ropsins: During the nuclear D explosion testing in the Pacific Islands in 1954, a combination of circumstances led to the accidental exposure of a group of Marshall Islanders, as well as some U. S. Navy personnel and the crew of a Japanese fishing vessel, the Lucky Dragon, to a