festamnieatea - mettat, NO ee Symia eet el, Bde Cohn, Robertson, Conard vielded data on the transmission of fission products between successive members of the ecological chain. Bods burdens of gamma-emitting fission products tsuch as Cs!8? and Zn’), measured by use of a whole-body counter, have correlated rather closciv with those estimated by radiochemical analysis of unne specimens. Estimates of the body burden may also be made from the Sr#¢/Ca ratio in the dietary intake. The estimates of bed, burden derived from Sr#° g of calcium ratios in the soil through various steps of the ecological cham to man van widely due to Inherent dimeulties in determining meaningful OR values from soil to plants. ‘The study of the fission products in the Marshallese people has becn complcated in several wavs. Thev were quickh evacuated from thei island after the accident and dhd not return to thear homes until 3 vears later. In the intenm Scars since the accident. additional weapons tests have been held whack fave L increased somewhat the amounts of the fission products in the environment. Finally. their dict now includes a vanety of unported foods. sc that the. are not tang in a Uclosed™ environment. and therefore mav not be rapids an proaching equilibrium wath the mssion products imait. While the data collected in this study of a Pacific Island commumity give an indication cf the internal radiation hazard resulting from acute and chrome eposun tedecs faflout. quantitate diffcrences might he capected a difiiscnt situations, For cxampic. the physical and chemical properties of the fabow material as well. meteorclogeal conditions and propertics of the biosphere. will influence strengh the uptake and retention ef Assen products im man vid the soil-plant- animal evcle, and thus will determinethe mternal radiation Lazard to man. For this rcason, considcrablh more rescatch 1s required on the transport of low levels of fission products Lespecialls Sr". an food chains and tnogeochemical eveles to determine the fate of radioisotopes im an cnvuironment, and thus to predict the potential internal radiation hazard to human beimgs Ining in fallout-contaminated arcas. Lirerature Crrep Alexander. G. Vu Nusbaum, R. E.. and MacDonald. N S§., 1956, The rmlatne retention of strontiun: and calaum in bonetissuc J Biol. Chem. 215: 911-919. Anderson, E. C.. Schuch, R. L.. Fisher, W. Ro. and Langham, W. 1., 1957, Radio- activity of people and milk. Science 128: 552 $S6. Blume. J. M.. and Smith, D.. 1954, Determination of exchangeable calcium and cation exchange capacity by equilibration with Ca, Soil Sci. 77: 9-17, Bond, V. P.. Conard, R. A., Robertson, J. S.. and Weden, E. A.. 1955, Medical ex- amination of Rongclap people 6 months after exposure to fallout. WT-937—Oper ation Castle, Addendum Report 4.1A. Bryant. F. J.. Chamberlain, 4. C.. Spicer, G. S.. and Webb, M.S. W., 1958, Strontium in dict. But. Med. J. 2: 1373-1375. Cohn, S. H.. 1959. (Unpublished data.) Cohn. S. H.. Rinchart. R. W.. Robertson, J. $.. Gong, J. K.. Milne, W. L., Chapman, W.H., and Bond, V. P., 1955, Internal radioactive contamination of human 328 , ‘ ‘ . . -