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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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,iven equilibria organburden can be determinedfkom the following: Mean time in referencehgan CONFIRMED TO BE UNCLASSIFIEb
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:~:*torof three (see pare 4.21, page 17) of the value 600 pCi/daythat is i ~:tuallyequfvalentto the RIG. It is assumed,however,that there is grm of calcim intakeper dsy which, short of eane~dletary_supplement, guideswould be about 250 and 750 pCl/dq. l%e Ad Roe Cmmittee recommendedadd- calciumto the Bikinidiet, Effectzvehalf-lifeIs 463 days. Fksctionreachlagorgan is 0.1
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J%e ICf? referencelists spleenrather than whole body CTmn. Guetafsonprobablyused whole body so that the Par spl.een,the followingis obtsixkd: as the critical doses would be gives an uncontrolled area Mpc for 95Fe for water of 8 x 10 Assumingan intakeon a per dq basis we ha*: Table VI' is only about l/5 of At equilibriumthe initialbody burdenwould Lxitia;dose rate would be: Dose = Initialdose rate This ie about one half of the Table VII' five year dose far 137Ce.
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Doee - 0.06 &i dey x 0.5 rad yr me diet of the young child,1 to 2 years of age, will be different 1':m that of adults,but if the intakewere es high as 2,290 pCl/day, the followingbody burdenwould be obtained:
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Z&e whcie body doee would beg Thus the 5 year dose would be about 276 mrad which ie not eigniflcantly veater than the dose to the adultsf?cm l37Ce.
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t . Brief Summary of the WaJiolugical Status, of the Bikini Atoll Pollout Studies Branch Division of Biology and Medicine .. A number of radiological surveys of Bikini Atoll have been made since 1446. The most recent survey was conducted in April and May 1967. The -.:;liu cr‘lort: was devoted to the measurement of ambient radiation levels .using _SCvCraj types oi detectors. The external radiation field was mapped in cons;dcrabLc? detai 1 on Bikini and Eneu Islands, and less thoroughly on the zcmaindcr of the atoll. The various radionuclides and their Concentrations Jn,ch ~‘JVC rise to the observed radiation field were determined from field which might‘bc eaten by the returning natives were collected and have been analyzed for radioactivity. i The results of the 1967 survey provide a basis for making reasonable I_! L timcites of the total (external plus internal) radiation exposure which tlrti Bikiniins might receive over the’coming years, if they return to the ai2.i. Background radiation on the atoll is?due almost exclusively, to c;p;nic radiation, and there are only trace amounts of the naturally occurring racioelements in the area.. Ekcept in the immediate vicinity of nuclear ietona t ions , the composition of the residual gamma-ray radioactivity was u_.milar throughout the atoll; consisting of about 70%137Cs, EO place; Eneu was the least contaminated, followed by Bikini Island itself. A dose gradient existed across Bikini, u;;U liigi.tist values in the heavily overgrown interior,
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; Y::.Y-A-’v:riOus people ore located, and for what periods or’ time, within the r;;i;rl:J c0mples. Lociltion in turn dizpcnds upon whether they are men, votiien, “a .:L.inuS, t tc. (3) The Bikiniins have become accustcae to eaticg WY .‘JJS, and will probably continGe to eat such things as rice, flour, canrxd
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.id:c co:’I spccics were either locking or present in very low concentration. l 6 notice? of the possible daily intake of the above three radionuclidcs may .U obtained by taking the diet eaten by the RongelaBesc as a guide, and itsing t& obscrvtiti concentrations of radioactivity in the same food items aiicctzd on Bikini. The resultant daily intakes are shown ‘in Table 3, and compared with the daily intakes which will lead to acceptable body burdens indlviduols and a suitable sample of the population. Special procedures w..ich w_AL greatly reduce the 90 .Sr content of the fruit can be undertaken u: pianting when edible panda& is re-introduced to the Atoll. Edible ir\;it would be available about five years after planting. The fact that sight have been fruit will not be ivailable for several years removes what the major source of “Sr %ntake and materially reduces- the well. Removal also of land crab meat from the diet seems . odvisable, and such restrictions bring the g”Sr intake down to 115 pCi/day Doses to bone the whole body from 137Cs and “Fe were calculated assuming that the diet occurs only from radioactive decay. computed. Because of marked differences in metabolism, adults and children .were considered separately for internal dose purposes. The total doses to whole body and to bone for children and adults from internal and axternai radiation over S-r 300 and 70;year intervals starting ,:. 1570 are indicated in Table 4. The doses acceptableI. . fat individuals and Zoz L suitable sample of the population during the.&ame time intervals are
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Tnc cstimatcd 90 Sr dose to bone is maximal because additions of calcium ’ It appears unlikely that, with moderate restrictions on living end eating .:&its; tk dose to the whole body or to bone will reach 2 reds in 5 years, :G radz in 30 years OF 16 ,rads in 70 years.
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from Bikini Foods, (pCi/day) ““* Acccptoble intake for 600 pCilg Ca 7,000 87,000 Jr “Sr and 137 Cs are removed in the processing of arrowroot to make flour ‘v This diet contains 0.42 g calcium per day - Calculated in the following way: . where the value of the MPL for individuals is l/10, and for suitable sample is l/30 of the value for radiation workers’ . ***Other foodstuffs, (free from radioisotopic contamination) necessarily will supplement this diet. .
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Summary of Radiation Esposurc Bone Whole body Whole Body Whole Body Bone