Medical Status of Rongelap People Five Year Exposure to Fallout Radiation

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In March 1959 the regular apllttal medical was carried at on the Rongelap people who had received tha heaviest exgosure to radiosctive fallout five gears previously in the accident which occurred following tbe expexdmental detonation of a nuclear weawn. The em nations were conducted on Ron&ap Island t o which the people had returned in July 1957. On their return, they were aceompmied by an equally large group of unelgposed relatives. This latter group has served as a ems on population for the medical studies. These 811l1uB1 surveys are carried out under t h e direction of mission with the strpport of the Wust !krrttory of tfie Pacific Islands, the Ikparhent of Defense, and other governmental agencies. A team of 20 phigaicians, scientists, andtechnleians, speciallsts in the field of radiation medicine, carried ant the survey on Rongelap Island. On asrival of the team at Rongelap there was scue question in the lninds of some of the people as t o the necessity of having further emt iom. toward their die- of the blood sampling. It wa8 also Svideat that the need for tba examinations created s a w concern in the minds of the people about theis bealth status. Sarree also were copcerned a m the radiologicsl safety of their food amd water for ccnmumptlon. T k people were reassured that their health was geaerslly good and tbir food snd water &e for constPlrptia9, and tbe 3mportance of continued exminations and trewhent in order t o help insure their continued good b a t h was the people coopemted extreme* well with tbe medicsl team i n CarrJrlng out the examhations. Objections to tbe erappinations were -1- directed These explm#%tIogsappeared t o aUed&tetkir fears and

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The examinations included aredical histories, c-lete pmicd examinations, and blood and other laboratory e-tlollS. in a steel room and From radlocherpical a i s of urriae samples in order to determine their body burdens of rsdionuclides. Analyses of the data are not complete and those data refemin&t o this recent 8u~peymust be cansidered as prelintnary in nature. I n conJuction with the exsmiastlsss, consfderable medical and dental treatment gf t k people w&s carried out to the extent possible under field conditions. ray activity were obtained fhxm individuals measured Following the accident, the Rongelapese had shown signs of significant exposure t o radiation such as short-Uved loss of appetite, nausea, vomiting, depression of their blood - foe tis8u68, wtltlple burns of the sldn fkom beta exgosure and internal absorption of fiseion products . Findings of the past surveys revealed that the people bve recovered from the acute effects of their radiation exgosure. diseases, illnesses or deaths have occurred which eoald be directly related t o their radiation exgosure. The incidence of all diseases noted has been about the 8- i n both tb exposed and uuexpsed control groups examined. The general physical condition of both e3lposed and uuescposed people on the island appeared good and their nut rl t lolla l status was satisfactory. wrrfng tbe past gesr one death occurred i n a 35 --old man, bringing the total deaths in the eqosed p u p to 3 for the five ye- period. This represents a death rate about equal t o that of the Marsball IslaBde as a whole (about 7 deaths per 1Mx) population per year). Findings, previously reported, which were interpreted 8s suggestive of a slight lag in growth and developmnt of the children durizag the f i r s t few gesss af’ter exposure are being re-evaluated on the basis of more enract age d a t a obtained on the pewt surveye The results of this eara3uaefon are not ccsqphte enough to Bpake any statements at present. Om case of cancer (ovarian) developed i n a 61 --old female dxlrfig the past year, the first case of cancer noted i n either the exposed o r unexposed populations. There is m reason t o belleve tbat t- cancer is refated t o radiation effect. Fertility does not sppear t o have been afYected since ths birth rate has been hfgher in the exposed thsn in tb uuexposed Marsue see A samewhat increased prevalence of miseamiages and stillbirths has been noted in t h e exp~wedgroup, but due t o paucity of dtal stakistics on the MaJps€dUese and the s m a l l mber of people involved, no statistical analpis is possible.

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Recovery of the blood-forming tissues is Judged virtually complete according to studies of tbe pez-ipheral blood counts. A possible exception is seen i n the blood platelets which are slightly below the levels i n the am posed group but still within the nornral range. !!!here is no evidence of any untoward effect associated with The beta burns of the skln healed mpidly during the first of the skin and pigment c m e at the f o m m site of deeper bums. Eowwer, no etrfdence of any cancerous change in these scars is noted. In those that l o s t hair, regrowth of nom hair was complete by s i x months after emsure. Very little is known about late effects of radiation in bmawn Increased incidence of leukemia in the exposed Japanese peoplebeings. k s been noted and, i n rrninwf studies, the following late effects of radiation may result: life shortening, mture aging, increase i n degenerative diseases, increased incidence of Pralignsnciea, opacities of the lens of the eyes, and genetic changes. The lrlarsballese have been carefully emmined for evt-ces of such changes, but none have been seen. Radiation-induced leubmia is kwwn t o appear relatively soon after exposure and other tspes of malignancy at later times. Therefore, continued examinations are essential i n order t o detect and, if possible, treat such effects should they develop. The lpadioactive fission products that had been absorbed internally by the Rongelap people were never suff'fcient i n aaiomt t o result in acute effects. These radioactive me;teria3s were excreted rapidly during the first six mmths after -8Ure. The island of veys showed the island t o be safe f o r habitation by the strmper of 1957 when the people were returned t o Rongelap. of radioactive msterfals ia these people is an lplportant paxt of the aedlcal sumre~ns. A 21 ton steel mom with very sensitive radiation detecting eqaipaent hats been used in the past 2 annual survejrs st Rongelap to determine the body burdens of radionuclides. In addition numemu8 M n e samples have been agalyzed for radioactivity. The results of these studies show that the has been an increase i n body return -bo Rongelap. About the same levels of these isotopes have been noted in those exgosed and,unexposed. Studies of the body burdens burdens, pfincipally of Cesid3?, ZincY?5 and Str on ti do, since their

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During the first 8 monthe m e r their return t o Rongelsp their body burdens of C e s i d n are estimated to have increased bY fact s up to 100 (resulting in a mean b ~ d yburden of 0.68p); rate of excretion in the urine. for est-ting the body burdm of StrontidO. TUS is frcnu a Rongelap m ~ l lwho died t o Rongelap) which showed On the basis of North for children would be higher. survey period, 8 t o X) mnths aFter return to Rongelap, it appears tbat the people have begun to attain an equilibrium with their lightly contaminated environment. he Cesid - 3 1 IS appear t o be slightly he StrontiUmgO analyses, &ortunat-, are not available yet. body burdens estimated above are far below the March 1959, five gears mer em sur t to fallout radiation, showed that the people h d recovered Fromr ths acute effects of their radiation ex@osure and appeared to be generally i n good health, !€'he following specific statements can be made in regard to their H a t i o n health Zincr5 is estinrsfed t o have shown a concomitant increase (mean body Str on tid showed abaut a twentpfold increased Only one saapple of bone is available mnths after his return Calcium (Strontium units) .expcted that the values Based on pre- anslgsis of data f'rom the most recent lower tban the year before, while tb zincr5 hss increased slightly. status: 1, go illnesses o r diseases were found directly associated with acute radfation effects. 2. One case of cancer and three deaths with no direct relation t o radiation effects. that could be have occurred, but 3. Fertility does not appear to b v e been affected. The incidence of miscarriages and stillbirths appears to be sopilewhat higher than in the uneqosed Msrsballese, but a deflcfency of vital statistics precludes definite conclusions as to whether or not this is a radiation effect. 4, Suggestive evidence of slight lag in growth and developent of exposed children noted previously is being re-evaluated on the baes%sof wtter age data olYt8ind during the past survey. 5. Blood platelet lmls are within the nomsl range but s cae wb t blow tbat for the unexposed population.

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6 . only 12 cases show resi- changes in the skin from beta burns. None sbow any evidence of cancerous cl.lsnge. 7. Possible late effects of wdistion such as shortenof life span, premature aglng, increased incidence of leukemAs and malignancies, increased incidence of degtmektive diseases, opacities of the lens of the eyes, and genetic chsnges bve not been observed. 8. The original body burdens of internally absorbed fission products appears to be too low to have produced any acute or longzlinc 5 and Str on tia. wxdmum permissible dose and it is not believed any untoward effects The return of the people to the slightly contamiaated is-d of Rongelap has caused some increase in body burdens of Cesium137, However, the levels are far below the accepted In view of the limited knowled,ge of the late effects of radiation i n humn beings, it is considered essential %bat medical surveys of the Rongehp people continue to be carried out in order to detect and treat Immediately any possible further effects of radiation that might develop. Though body burdens of radioactive isotopes are w e l l below the accepted permissible dose levels and no further signlficant increase in these burdens is anticipated, a close check on these levels during future nedieal surveys is indicated. Head, Marsball Island Medical Surveys