MEDICAL SURVEY OF RONGELAP PEOPLE SEVEN YEARS AFTER EXPOSURE TO FALLOUT Introduction Theresults of a medical survey of the people of Rongelap in the Marshall Islands, carried out in March 1961 at 7 years after the accident, are presented in this report. These people had been accidentally exposed to fallout radiation following a detonation of a high yield thermonuclear device during experiments at Bikini in the Pacific Proving Grounds in March 1954. An unpredicted shift in winds caused a deposition of significant amounts of fallout on four inhabited Marshall Islands to the east of Bikini (see Figure 1) and also on 23 Japanese fishermen aboard their fishing vessel, the Lucky Dragon. Ofthe inhabitants ofthe istand of Rongelap, 105 nautical miles away from the detonation, 64 received the largest fallout exposure: an estimated dose of 175 r of whole-body gamma radiation, contaminationof the skin sufficient to result in beta burns,-andslight internal absorption of radioactive materials through inhalation and ingestion. Another 18 Rongelap people away on a nearby island (Ailingnae), where less fallout occurred,received only an external gammadose of about 69 r. There were 28 American servicemen on the island of Rongerik further to the east who received about the same amountofradiation as did the Rongelap people on Ailingnae. Lastly, 157 Marshallese on Utirik Island, about 200 miles further east, received about an estimated 14r of whole-body radiation. The fallout was notvisible on this island and noskin effects developed. The exposed people were evacuated from these islands by plane and ship about two daysafter the accident and taken to Kwajalein Naval Base temporaryvillage was constructed for the Rongelap people on Majuro Atoll several hundred miles to the south, where they lived for the following 3% years and were examined at yearly intervals by a special medical team. In July 1957, after careful evaluation of the radioactive contamination situation, Rongelap Island was considered safe for habitation. A new village was constructed, and the Rongelap people were moved there by Navy ship. The annual medical surveys have since been carried out on Rongelap Island. A group of more than 100 Rongelap people, who wererelatives of the exposed people but had been awayfrom theisland at the time ofthe accident, moved back with the Rongelap people to their home island and have served as an ideal comparison population for the studies. Following the initial survey of the Utirik people on Kwajalein in 1954, a repeat survey was carried out in March 1957. In addition, during the past survey, as in the previous surveys, a visit was made to Majuro Atoll to examine a group of children who represent part of the control group used for the growth and development studies of the exposed children. 2 ee PRONGERIK” - ~ AILINGINAE'S”"RONGELAP : _ DSUTIRIK © 0 aL. A\owasaten Yo S 9 about 150 miles to the south, where they received 8 extensive examinationsfor the following three months. In view of the generally negative findings on the American servicemen, they werelater re- 2 were also allowed to return to their homeisland, 0 turned to their duty stations. The Utirik people whereradioactive contamination was slight enough to allow safe habitation. Because Rongelap Atoll was consideredto be too highly contaminated, a Figure 1. ° MAJUROSS Map of fallout area (March 1, 1954), Marshall Islands. ee