. . . . Mae - tape whee Gare ond Wettig bhi he Oa ke Bae aerie BR OE ke Me etree Ge ve eee RS RSS hog ST Toe Re te in transferring ibe caries from peigase por! or made to intake bs mar.oon a af the barpesnive fiebt of radiacccin cwis devoted to studies ar this asnet Sens. Fils. + ri . ‘ Horeost camrion form, 212 sy sciuble Coets. e ie chy 0G dave enirennienl (O man in signiieant quantity exc, by direc: jabulat on or a contanpnated wound (206, 207) Otner nuclides mn fond to curce irate in one or more organism or vector in the ecosvsiem, Ultirs. te accumulation in van derenads unos whether or not this critical step is favo 2! ‘ o~ by-passed. Concentration factors of several thousand are not uncorimon (208). ‘ Much etfort has been and ts being expended in identifying critical pathways (209, 210) eu.. air-leaf-caw-milk-body versus air-soil-plant-cow-mil.-body. Reeent work isakei nh ovr Jiat foliar absorption of many nuclides is siren. orn. in greater than that through root systeras to make thefirst the “erttical pati. e.g. ?'Sr in manyinstances. However, this is not the critical pathway uf naik or deiry products are not consumed. In this event, the critical pathway may iostead be through grain as is the case in the Orient, and the resultant intale i.uey oe guite different. Another aspect is the identification of critical nuclides (209, 211). The isotopic composition of discharges differs with the type of reactor and the time ¢* cperation, and it is different for a fuel processing facility than for a reactor. T.ius, the eriuical pathway will not necessarily be the same for different os pes of orc: tion. Of special concern has been tie possibility of an undetected critical putaeey or critical nuclide. The role of zinc-65. for example, was not epprec ated uni! Japanese investigatory drew attention to it (212). The primary likelrthoed for such a fincing nowis in aguatic environments, especially oceanic (213, 24. and in the cevelopment ¢ovo iferent fuel cycles. “ot da pe Corgo.ten either, is the vo'e of urne. since isovopes ofiarportor.2 ue fresh ussier products bec.ome less significant Jater on. Indeed, if times ore (one zs in the consideration of radioactive waste disposal, some very Uneitocice nuciiues become “ critical” 10 the evaluation of poiential nazurd (id) An excellent summary of the fuctors to be considered iu ihe instance. v6 é single river systemin Europe is seea in the paper by Feldt (215). i ‘ \ yrs . eepid os * whiibariteadoe« aay! oe Radionuclide effects on “lower” organisms.—-Quite apart fom the moverce:: of radionuchdes through an ecosystem to man is the passimaty of daicser +. Wi / eifects in i. wer Organisms. This assumes importance to ini in proparue. foi: < aks pd eaporcarc*~ of that organism ‘o the ecosystem or as a Mernper of a * Keciauor ePects have aow been ciearly demonstrated tn hign:l cou: ; pe . wry fe wy et b poe gw ey det abet ye ! : | ' ‘ : Sand cba al seusystems satea us a trey woo Me Sey bo J barm seme siererses. eg, the relvevels tron ceestnvitv or corcrers Wee ce ete ren. und marked differcace HO SWHy Ot ll sd i. ey be hen Bigs , j ryeh omte: control, sve't as White Oak Lake ot Oak Ridve Hireol-y widie Fo. 2 been directed at determining the radioseusiti ow oF ariem'.* a “a WY i \ é . Pfs C0 Coin avrment lo, a ; wSt Crganisois, no key crginiem has yet upresred with such exquisite sersitivirny and in a key posiuon in an ecosysiem) fo need , a : i . i + STORRS NEARY «OR+ EERE TPTRY EROEEREAPOT?94TORRYHeNEARESTDSS NLS GS seed \ a PM ye ws sy o a ae ETE fel gps an Ly + ENE ie . , so we \ \ | | I | . ; . 1 Wy aa . spe eng . tt te PEIRCE ST . ‘ : . 1 : Foe a at pee ROI gay oe I Rbk atee : ye ve ‘. codes cad etme SME a Te ag eet at er Fae dae res ane 2 LT) et oe Re er atteebay been rove eo Une bah bevet Hem ng fe Pee ey