MEDICAL SURVEY OF THE PEOPLE OF RONGELAP AND UTIRIK ISLANDS ELEVEN AND TWELVE YEARS AFTER EXPOSURE TO FALLOUT RADIATION (MARCH 1965 AND MARCH 1966) Introduction Theresults of a medical survey of the people of Rongelapin the Marshall Islands, carried out in March 1965 and March 1966, 11 and 12 years after the accident, are presented in this report. These people had been accidently exposed tofallout 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 ofsignificant amounts offallout on four inhabited Marshall Islandsto the east of Bikini (see Figure 1) and also on 23 Japanese fishermen aboard their fishing vessel, the Lucky Dragon. Of the inhabitants of the island of Rongelap, 105 nautical miles away from the detonation, 64 re- ceived the largest fallout exposure: an estimated dose of 175 rads of whole-body gammaradiation, contamination ofthe skin sufficient to result in beta burns, andslight interna! absorption of radioactive materials through inhalation and ingestion. Another 18 Rongelap people away on a nearby island (Ailingnae), whereless fallout occurred, re- ceived only an external gammadose of about 69 rads. There were 28 American servicemen on the island of Rongerik further to the east who received about the same amountof radiation as did the Rongelap people on Ailingnae. Lastly, 157 Marshallese on Utirik Island, about 200 miles further east, received an estimated 14 rads of whole-body radiation. Thefallout was notvisible on this island and noskin effects developed. The exposed people were evacuated from these islands by plane andship about 2 daysafter the accident and taken to Kwajalein Naval Base about 150 miles to the south, where they received extensive examinationsfor the following 3 months. During this period vigorous efforts were necessary to decontaminate the skin completely (see Figure 2). In view ofthe generally negative findings on the American servicemen, they were later returned to their duty stations. The Utirik people werealso allowed to return to their homeisland, where radioactive contamination was slight enoughto allow safe habitation. Because Rongelap Atoll was con- sidered to be too highly contaminated, a tempo- .& UTIRK , aL, \ewanen Vv © 9 9 2 Figure 1. Map offallout area, Marshall Islands, March 1, 1954. ° Figure 2. Marshallese bathing in lagoon at Kwajalein in March 1954 to decontaminate skin and hair after fallout contamination.