RMI Nuclear Justice Documents

MEDICAL SURVEY OF RONGELAP PEOPLE, MARCH 1958, FOUR YEARS AFTER EXPOSURE TO FALLOUT Background — This report presents the results of a medical survey carried out in March 1958 on the Marshal- lese people of Rongelap Atoll who were acci- dentally exposed to radioactive fallout in March 1954. The accident occurred following the detonation of a high yield thermonuclear device during experiments at Bikini in the Pacific Proving Grounds. An unpredicted shift in winds caused a deposition of significant amounts offallout on four inhabited Marshall Islands nearby and on 23 Japanese fishermen aboardtheirfishing vessel, the Lucky Dragon (see Figure 1.) Sixty-four inhabitants of the island of Rongelap, 105 nautical miles away from the detonation, received the largest fallout exposure: an estimated dose of 175 r wholebody gammaradiation, beta burns andepilation from contamination of the skin, and slight internal absorption of radioactive material. Another 18 Rongelap people away on a nearbyisland (Ailing- nae), where less fallout occurred, received only abouthalf this exposure. Twenty-eight American servicemen on the island of Rongerik further away received about the same amountofradiation as did the 18 people on Ailingnae (about 70 r). Lastly, 157 Marshallese on Utirik, about 200 miles distant, received only about 14 r whole-bodyradiation. The fallout was notvisible on this island and noskin effects were seen. The exposed people were evacuated from these islands by plane and ship about two days after the accident and taken to Kwajalein Naval Base about 200 miles to the south, where they received extensive examinations for the following 3 months. In view of the generally negative findings on the American servicemen, they were returned to their duty stations. The Utirik people were repatriated to their homeisland, where the radioactivity was considered to be low enoughfor safe habitation. Because Rongelap Atoll was considered to be too highly contaminated, a temporaryvillage was constructed for the Rongelap people on Majuro Atoll several hundred miles to the south, where they remained for the following 342 years. In July 1957, after careful evaluation of remaining radiological hazards, Rongelap Island was foundsafe for habitation. A new village was constructed, and the Rongelap people were moved there by Navy ship. The present survey was therefore carried out at Rongelap Island. SUMMARYOF PAST FINDINGS Reports have been published on thefindings of surveys madeatthe following times after expo- sure: initial examinations,' 6 months,’ 1 vear.? 2 years.‘ and 3 years.> The followingis a brief summary ofthese findings. During the first 24 to 48 hr after exposure, about % of the Rongelap people experienced anorexia and nausea. A few vomited and had diarrhea. Many also experienced itching and burningofthe skin and a few complained oflachrymation and burningof the eyes. Followingthis, these people remained asymptomatic until about 2 weeks after the accident, when cutaneous lesions andloss of hair developed due largely to betair- radiation of the skin. It was apparent when the people were first examined, a few daysafter exposure, that the lymphocytes were considerably depressed andthatsignificant doses of radiation had probably been received. In addition to the whole-body dose of radiation and the beta irradiation of the skin, radiochemical analvses of the urine showedthatsignificant amountsofradio- active material had also been absorbed internaily. The effects of the radiation can best be summarized underthree headings according to the modeof exposure: penetrating irradiation. skin irradiation, and internal irradiation. Penetrating Irradiation The changes in the peripheral blood of the more heavily exposed Rongelap people who received 175 r will be reviewed below (see Figures 7, 9, 12 and Tables 3, 4, 5). The changes in the Ailingnae and Utirik groups were similar but less marked. Certain unexplained fluctuations have occured from year to year in the peripheral blood levelsof the comparison populations as well as of the exposed groups. Depression of the peripheral blood elements as represented by mean populationlevels occurred as follows.