Medical Survey of Rongelap People Five and Six Years After Exposure to Fallout (with an Addendum on Vegetation)

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MEDICAL SURVEY OF RONGELAP PEOPLE FIVE AND SIX YEARS AFTER EXPOSURE TO FALLOUT JOHIQ lAMAN, PRACTITIONER, AND JACK HELKENA, PRACTITIONER

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MEDICAL SURVEY OF RONGELAP PEOPLE FIVE AND SIX YEARS AFTER EXPOSURE TO FALLOUT (With an Addendum on Vegetation) JOHN IAMAN, PRACTITIONER,2 AND JACK HELKENA, PRACTITIONER with the technicalassistanceof WILLIAM A. Scorn, 1 EMIL ADAMIK, I ROBERT SMITH, 1 IRVING JONES,4 JAMES GILMARTIN, 1 1Brookhoven Nationol Laboratory, Upton, New York 2Department of Public Health, Trust Territory of the Pacific Islands 3Walter Reed Army Medical Center, Washington, D.C. 4South Nassau Communities Hospital, Rockville Centre, New York ‘M.D. Anderson Hospitol, University of Texas, Houston, Texas 6Nationol Institutes of Health, Bethesda, Maryland 7Atamic Bomb Casuolty Commission, Hiroshima, Jopan 8Navol Medical Reseorch Institute, Bethesda, Maryland 9Memorial Hospital for Conc& and Allied Diseases, New York, New York BROOKHAVEN NATIONAL LABORATORY

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This report was prepared as an account of Government sponsored work. Neither the United States, nor the Commission, nor any person acting on behalf of the Commission: A. Makes any warranty or representation, expressed or implied, with respect to the accuracy, completeness, or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or proce~ disclosed in this report may not infringe privately owned rights; or B. Assumes any liabilities with respect to the use of, or for damages resulting from the use of any information, apparatus, method, or process disclosed in this rqxmt. As used in the above, “person acting on behalf of the Commission” includes any employee or contractor of the Commission, or employee of such contractor, to the extent that such employee or contractor of the Commission, or employee of such contractor prepares, disseminate, or provides access to, any information pursuant to his employment or contract with the Commission, or his employment with such contractor, PRINTED IN USA Available from the Office of Technical Services, Department of Commerce

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Beta Imadlation of the Skin .................................................................................. Difficulties Associated With the Examinations .................................................. Attitudes of Rongelap People .......................................................................... Lwation of Examinations ................................................................................ Studies of Aging Criteria .................................................................................. Studies of Genetically Inherited Characteristic ............................................ Radionuclide Body Burden Evaluation ..........................................................

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Review of Data on Mortality and Pregnancy Terminations Over the Past Six Years ........................................... 17 Grotihand Development Studies .................................................................. 20 Studies of Aging Criteria ...................................................................................... 28 Residual Beta Burns ............................................................................................ 33 Hematological Leukemia Suney .................................................................... 37 Sodium and Potassium Levels, 1959 ................................................................ 38 Studies of Genetically Inherited Traits ............................................................ 41

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Estimation of the Internal Radiation Hazard ................................................... 45 Whole. Body Counting ...................................................................................... 45 Analysis of Gamma. Ray Spectra .................................................................... 47 Radiwhemical Analysis of Urine .................................................................... 51 Whole-Body Counting With the Gamma Spectrometer ................................ 53 Importance of Medical Surveys .......................................................................... 58 APPENDIX 1. Rongelap Blind Counts,., ................................................................... 61 APPENDIX5. Individual WBC, Basophil, and Alkaline Phosphatase, 1959- 1960,. 70 APPENDIX6. Blood Groupings and Haptoglobins, 1958-1959, and ADDENDUM.A Note on the Vegetation of the Northern Islets of Rongelap Atoll, Marshall Islands, March 1959 ........................... 85

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MEDICAL SURVEY OF RONGELAP PEOPLE FIVE AND SIX YEARS AFTER EXPOSURE TO FALLOUT The results of medical surveys of the people of Rongelap in the Marshall Islands, carried out in March 1959 and in March 1960 at 5 and 6 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 Luc~Y Dragon. Of the inhabitants of the island 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, contamination of the skin sufficient to result in beta burns, and slight 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 gamma dose of about 69 r. There were 28 American servicemen on the island of Rongerik further to the east who received about the same amount of radiation as did the Rongelap people on Ailingnae. Lastly, 157 Marshallese on Utirik Island, about 200 miles further east, received about an estimated 14 r of whole-body radiation. The fallout was not visible on this island and no skin effects developed. 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 150 miles to the south, where they received extensive examinations for the following three months. In view of the generally negative findings on the American servicemen, they were later returned to their duty stations. The Utirik people were also allowed to return to their home island, where radioactive contamination was considered to be of a slight enough extent to aliow safe habitation. Because Rongelap Atoll was considered to be too highly contaminated, a temporary village 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 Naw ship. The annual medical surveys have since been carried out on RongeA group of more than 100 Rongelap people, who were relatives of the exposed people but had been away from the island at the time of the 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 sutvey, 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 Figure 1. Map of fallout area

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The accumulation of data from these surveys is becoming increasingly voluminous. Since conditions have not been favorable for performance of extensive statistical analyses or use of electronic computing procedures to store and manipulate the data, the annual survey reports published by this Laboratory are made as complete as possible. This report, therefore, includes a considerable amount of raw data, much of it in appendices, so that others may have an opportunity to make further calculations if desired. This report also contains a brief addendum on the vegetation of Rongelap Island. Summary of Past Findings Reports have been published on the findings of surveys made at the following times after expoyears,’ 3 years,’ and 4 years.’ The following is a brief summary of the findings previously reported. During the first 24 to 48 hr after exposure, about 2A of the Rongelap people experienced anorexia and nausea. A few vomited and had diarrhea. Many also experienced itching and burning of the skin, and a few complained of lachrymation and burning of the eyes. Following this, the people remained asymptomatic until about 2 weeks after the accident, when cutaneous lesions and loss of hair developed, due largely to beta irradiation of the skin. It was apparent when the people were first examined, a few days after exposure, that the lymphocytes were considerably depressed and that significant doses of radiation had probably been received. In addition to the wholebody dose of radiation and the beta irradiation of the skin, radiochemical analyses of the urine showed that measurable amounts of radioactive material had also been absorbed internally. The effects of the radiation can best be summarized under three headings according to the mode of exposure: penetrating irradiation, skin irradiation, and internal irradiation. The changes in the peripheral blood of the more heavily exposed Rongelap people who received 175 r will be reviewed in the section on hematological examinations (see Figures 33, 35, and 38, and Appendices 1 and 2). The changes in the Ailingnae and Utirik groups were similar but less marked. Certain unexplained fluctuations have occurred from year to year in the peripheral blood levels of the comparison populations as well as of the exposed groups. Depression of the peripheral blood elements as represented by mean population levels occurred as follows. Lymphocytes fell promptly and by the third day were about 55% of the control values in adults, and slightly lower in children. There was only slight recovery after six months. At 2 years, although further recovery was evident, the mean values of these cells were still found to be. below the comparison population levels (75 to 80~0). At 3 years the mean lymphocyte counts were slightly below those of the comparison population. At 4 years the mean level appeared to be about the same as that of the comparison population, but many counts remained lower. Neutrophil levels fluctuated considerably during the first few weeks but fell gradually to a low of about 50’%0of comparison population levels by the 6th week after exposure. Slow recovery ensued, but at 6 months they were still slightly beIow the unexposed levels. However, by 1 year post exposure they had returned to the level of the comparison population and have remained so, with the possible exception of those of children <12 years old, which generally have been lower than those of the unexposed children of comparable platelets fell to about S()?t. of the unexposed values by the 4th week. By 6 months they had reached 70~0 of the controls; at 1 year the mean platelet count was still below that of the control population but higher than at the 6-month survey. Although further increases were apparent at the 2-, 3-, and 4-year examinations, the levels were still below those of the comparison population. Changes in hematocrit were not remarkable in any of the ,groups. Clinical examinations revealed no disease processes or symptoms which could be attributed to radiation effects, aside from skin lesions, 10SSof hair, and early symptoms. Epidemics of chicken pox and measles occurred. The diseases encountered were no more severe or frequent in the irradiated group than in the unexposed group, even during the period of greatest depression of peripheral blood elements. Three persons in the exposed population died of disease: ( 1) a 46-year-old man with a hypertensive beak disease which had been

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present at the time of exposure, who died 2 years after the accident; (2) a 78-year-old man who died, 3 years after exposure, of coronary heart disease complicating diabetes; and (3) a 36-vear-old man who died of acute varicella, 4 years after exposure, who had received only 69 r, having been on Ailingnae at the time of the fallout. There was no apparent relationship between any of these deaths and radiation exposure, and mortality in the exposed group did not appear to be greater than in the unexposed population. It was difficult to evaluate the effects on fertility. However, a number of apparently normal babies were born during the 4-year period, and there has been no discernible fall in birth rate. A slightly higher number of miscarriages occurred in the exposed women than in the unexposed group; this will be further evaluated in the present report. No opacities of the lens or other eye changes have been found that could be related to radiation. Studies on height, weight, and bone age seemed to show a slight degree of retardation in growth and development in the exposed children. However, the small number of children involved, and a later finding that exact ages of some of the children were in doubt, has resulted in a re-evaluation of these data based on more reliable age deterBETA IRRADIATION OF THE SKIN It was impossible to get an accurate estimate of the radiation dose to the skin. Beta burns of the skin and epilation appeared about 2 weeks after exposure, largely on parts of the body not covered by clothing, About 90% of the people had these burns, and a smaller number developed spotty epilation of the scalp. Most of the lesions were superficial; they exhibited pigmentation and dry, scaly desquamation, and were associated with little pain. Rapid healing and repigmentation followed. Some lesions were deeper, showed wet desquamation, and were more painful. A few burns became secondarily infected and had to be treated with antibiotics. Repigmentation of the lesions gradually took place in most instances, and the skin appeared normal within a few weeks. However, in about 157o of the people, deeper lesions, particularly noted on the dorsum of the feet, continued to show lack of repigmentation with varying degrees of scarring and atrophy of the skin. At 4 years the only residual effects of beta radiation of the skin were seen in 12 cases which showed varying degrees of pigment aberrations, scarring, and atrophy at the site of the former burns. Numerous histopathological studies have been made,’” and the changes found have been consistent with radiation damage. At no time have changes been observed either grossly or microscopically indicative of malignant or premalignant change. Spotty epilation on the heads was short lived, regrowth of hair occurring about 3 months after exposure and complete regrowth of normal hair by six months. No further evidence of epilation has been seen. An interesting observation was the appearance of a bluish-brown pigmentation of the semilunar areas of the fingernails and toenails in about 90~o of the people, beginning about 3 weeks after exposure. Bv 6 months, this pigmentation had largely grown out with the nail and had disappeared in most cases. The cause of this phenomenon has not Radiochemical analyses of numerous urine samples of the exposed population showed internal absorption of radioactive materials, probably brought about largely through eating and drinking contaminated food and water and to a lesser extent through inhalation. During the first few days when the body levels were at their highest, the maximum permissible concentrations were approached or slightly exceeded only in the case of strontium-89 and the isotopes of iodine. The concentrations were believed to be too low to result in any serious effects. Body levels fell rapidly, so that by 2 and 3 years post exposure, they were far below the accepted maximum permissible level; by 6 months activity in the urine was barely detectable. The return of the Rongelapese to their home island (which after careful survey was considered safe for habitation, despite a persisting low ievei of radioactive contamination) was reflected in a rise in their body burdens and increased urinary excretion of certain radionuclides. Beginning in 1957, gamma spectroscopy by use of a low-level counting chamber was added to the techniques of radiochemical analysis. This, along with radiochemical analysis of urine samples, showed an increase in body burdens of cesium- 137 by factors of up to 100 and of strontium-90 by a factor of 10 to 20; and …