WNITED STATES AQBRS ATOMIC ENERGY COMMISSION Washington, D. C, 20545 May 12, 1966 Mr. John T. Conway Executive Director Joint Committee on Atomic Energy Congreas of the United States Dear Mr. Conway: BEST COPY AVAILABLE This is to provide you with the most recent information on the occurrence of nedular thyroid abnormalities among the 69 surviving Marshallese Islanders exposed to falleut eon March 1, 1954. Dr. Robert Conard of the etaff of the Medical Department of the Brookhaven National Laboratory has just returned from the Marshali islands where he and his team during February-March 1966 conducted the latest of the continuing series of medical examinations of these peopie. Our last letter on this subject, dated October 26, 1965, advised that a cumulative total of 1] Marshallese had been found to have nodular thy- roids at the conclusion of the medical survey conducted during August 1965, 1963, A nodular thyroid was first detected during the survey of February The just-conciuded survey has disclosed five additional people with nodules, This brings to 16 the number of diagnosed cases of nodular thyroids among the 69 survivo:s of the original 82 at risk. The age distribution of incidence is shown below. Age at Exposure 1-5 6-10 11-15 16-26 > 20 Number Exposed __. 16 9 7 5 32 69 Total Incidence of Nodules through March, 1966 Number 9 4 0 0 3 16 Percent 56 44 - JCAE 9 mw25 Fifty-five of the 69 were on Rengelap Island and received estimated whole bady doses of 175 R pilus pessible deses of 700 to 1400 rem to their thyroids from the radioiodine. The reraaining 14 were visiting on Ailingnae, a nearby island, and received estimated 69 R whole body expesures plus less certain, but pxebatly emailer thyreid doses. None of the six children (1-10 years ef age) who were with the group on Ailiangnae has shown nodules, but one of o the three adults in the table was on Ailingnae.