STERS AL 5.3. DR POSTI EONS Internal Contamination in Humar Beings Tue INTERNAL CONTAMIN ATO study vas be gun 15 days post-detornation witho tie coection of pooled 24 hour urine amples trom the Marsnallese and Amer car cro aps Maxinmiun activity in the urine occurs dure the frst fex days after internal corfaniunater Ey 1 seek an approximate equilbrium state < reached on which the contaminants ren atancain the ped: are firmly fixed. chiefly a: ie skeletal ti-sueThe activity in the prime shen oemves fron radicelements which Lave beer penlacea ta the natural process of bie ogi tarnever “Mune, the study made is essen alo. tatoot an qu librium condition. The urine samples vere en om laboratories in the United States fer ana vss. + nce the high background encountered iy ie nelet niasied the relatively low levels «fo act its the alquet samples used. A Heli, biberatory as most dy sirable for a rapid sur ces. acid wie shown to be feasible, if adequate ficuetes re arovided for the counting of the sampues The first urimes sariples ment oned wove were collected for the Las NGamios SS dentitr Laboratory (LAST “ibalit amples oo lected $4 days post detor i con were usc ser there. On the 23rd. 24th detonation, 2t-hour uring ee sie Hoh divs post fectoaas from ene mdividual from Rongelar aad Aviungirae were sent tothe New York Operntio is Oifice. Aton Energy Commission NYO) VEC for ov In addition, -umples “rom represent. tive individuals ino these oreo were -ollecter alysis. Yio Sand § months cost cetera ar ine set to NYOO-AEC. The USNREGTL collected apes Team ney member of the exposec arr os att und fh days post represent: detonation, Sa tipies tives of these BOM pS toon. vere. se ea Sand 6 months by the FsNdil ected att is lnoadeition, samples fromia representa oe cronpoth Vier mms nd 200 Mire eee lected far eonsecutive detonation. oduys 0824 a ee MO TONUCTIDES 4) Methods 69 \-. omplere ridiochemical analysis of all leo oho saenp es was not feasiole, samples were pieced for ons sr") Balt the rare earth wrogooad fissile matertal These analyses are tt taast efit fer evaluating the concentra- jor at. ane ident ty of all the potentially hazardouternadky deposited radioactive isotopes. Miessarement vas also made of the gross beta eta ty d all the -amples. [oo fiaqitite the processing of the large numer Fone saples sent from the field, a seanvay faetiad for beta measurement consisting foaoadsth oAavate precipitation with a lanthatate ouerier Was emploved on an aliquot of the Shout inne san ples, This method rapidly oer tiates tae padioact,ve elements into a sat) Ordtne and eliminates the normal Ke’ MLK Prat \ carbonate precipitation of the entip? b aear saniple increased the sensitivity of ceasurement -atfiqently for analysis of ~tlepies oleered ater than Zl. months post feta atoan Phe peta aetivits was connted with a thin end soeow Crager Miatler counter The counter hae tl ber: tee werhiaw (LO) -tandard. and an (ppb obits eorrection for self absorption was Made ys. a So ranelard, Findings and Interpretations Bera vet vitx of the Urine. Internal depmtoon ot vadioacrive elements was evidenced . fou preence of significant umounts of beta ress oy the wrne. This activity deereased Sapa do.ous og fanetion of time. as it was derived rie fb. trem short lived radiototopes. eSatrple For aio natths post letonation, the mean wteote od the apne of adults from Rongelap was 2s percent oof the value measured £5 days pest detonatieu. cad oat Gomoenths, the activity me ene wos barely detectable in most of the eto dhl Comdparisar of the means of fhe urime samhes othe oudults frente Rongelap and ooo re anet frome Aimerietis from Rongertk Cot te ea tays pest detonation: the