THIS DOCUMENT IS W L I M ~, I. U. S. BIOASSAY INTERCOMPARISON STUDIES PROGRAM AT OAK RIDGE NATIONAL LAB

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1 ORNL/CP U S BIOASSAY INTERCOMPARISON STUDIES PROGRAM AT OAK RIDGE NATIONAL LAB * By G F Pyne, Normn Bores, K KMelton, nd J MRnkin, Ok Ridge Ntionl Lbor Office of Nucler Sfety, P Box 28, Ok Ridge, TN , USA Introduction: The Intercomprison Studies Progrm (ISP) for in-vitro biossy locted t Ok Ridge Ntionl Lbortory ( O N ) hs been in plce since My 1991 The progrm ws originlly creted to fill need (identified in 199 by Technicl Sfety Apprisl) in the Rdiobiossy re t O N,specificlly in the res of Qulity Control, Qulity Assurnce, nd Performnce Testing In the beginning, this consisted of two or three lbortories working in pilot intercomprisonprogrm Once it ws determined tht this could work effectively, the progrm begn to seek dditionl members to broden the scope of the effort The progrm becme formlized with qurterly report in Jnury 1992 The ISP currently provides cross-check blind/double-blind smples spiked with known mounts of rdioctivity to vrious Deprtment of Energy (DOE) fcilities, universities, nd privte industry orgniztionsthroughout the United Sttes These smples cn be pckged ccordingto ORNL procedures ( O Nsmple bottles, ORNL chin-of-custody forms, tmper sels etc), for single blind smple or ccording to the needs of prticulr fcility if the double-blind smple mode is to be mintined In 1998, the customer bse ws brodened to include Europen fcilities In Jnury 1993, the whole-body count progrm ws dded This involves ech prticipting fcility receiving block phntom fromthe ISP nd determining geometry fctor using known stndrd (Ech fcility keeps its own block phntom s long s they remin prticipnt in the progrm) At qurterly intervls, ech prticipnt receives n unknown smple for nlysis The smple is counted nd the dt is collected for publiction in n nnul report In October 1994, the fecl progrm ws dded This involves spiking n rtificil mtrix with known mounts of rdioctivity Lbortories receive unknown smples on qurterly bsis The smple is counted nd the dt is collected nd published in qurterly report The ISP Lbortory is set up to function in the sme mnner s routine biossy fcility This includes hving the cpbility to perform ll the seprtions nd nlyses tht would be crried out in typicl rdiobiossy lbortory, long with the necessry policies, procedures, nd document controls tht go long with these techniques The ISP lso mintins rchive smples which cn be nlyzed in the QC lbortory t the request of ny of the prticipnts if conflict or discrepncy in smple nlysis/result occurs Urinlysis Progrm: Prticiption in the (ISP) urinlysis progrm is usully on monthly bsis Urine is collected nd frozen until it is redy for use Ech month pproximtelyfifty liters is thwed, nd pooled in crboy for smple preprtion The tifly liters is divided into smple btches (Typiclly btch cn be nywhere from 2-15L) Ech btch is spiked with known mount of rdioctivity fiom n ISP stndrd nd is llowed to equilibrte overnight The rdionuclides (spikes) used re ll Ntionl Institute of Stndrds nd Technology (NIST) trceble nd the subsequent primry, secondry nd tertiry stndrds prepred re done so using semi-micro blnce which hs been clibrted nd functionl checked using NIST trceble weights After equilibrtion, the btch is then divided into one liter smples, tgged by ORNL Helth Physics nd shipped to the vrious prticipnts in the progrm Below is list of the rdionuclides nd the spike levels tht re commonly used in the progrm: Th-nt: Th-nt: Th-nt: U-nt: U-nt: U-nt: D~sfR~WTf@4 OF less thn 1 dpdliter 1-5 dpm/liter 5-15 dpdliter less thn 1 dpm/liter 1-5 dpm/liter 5-15 dpndliter THIS DOCUMENT IS W L I M ~, I Y The submitted mnuscript hs been uthored by contrctor of the US Government under contrct No DE-AC5-96R22464 Accordingly, the US Government retins nonexclusive, royltyfree license to publish or reproduce the published form of this contribution, or llow others to do so, for US Government purposes

2 DISCLAIMER This report ws prepred s n ccount of work sponsored by n gency of the United Sttes Government Neither the United Sttes Government nor ny gency thereof, nor ny of their employees, mkes ny wrrnty, express or implied, or ssumes ny legl libility or responsibility for the ccurcy, completeness, or usefulness of ny informtion pprtus, product, or process disclosed, or represents tht its use would not infringe privtely owned rights Reference herein to ny specific commercil product, process, or service by trde nme, trdemrk, mnufcturer, or otherwise does not necessrily constitute or imply its endorsement, m m- mendtion, or fvoring by the United Sttes Government or ny gency thereof The views nd opinions of uthors expressed herein do not necessrily stte or reflect those of the United Sttes Government or ny gency thereof

3 less thn I d p d i t e r 1-5 d p d i t e r less thn I d p d i t e r 1-5 dpdliter less thn 1 d p d i t e r 1-5 dpdliter less thn 1 dpdliter 5-2 dpdliter 5-1 d p d i t e r 5-1 dpdliter 5-5 d p d i t e r less thn 25 dpm/ml 25-5 dpm/ml 5-5 d p d m l 5-5 d p d m l 5-1 d p d i t e r 5-1 d p d i t e r Pu-238: PU-238: Pu-239: Pu-239: Am-24 I : Am-24 I : Cm-244: Tc-99: P-32: Sr-9: Sr-9: H-3 : H-3: C-14: s-35: CO-6: cs-137: ~ All rdionuclides re NET trceble stndrds prepred by NIST with the following exceptions: Th-Nt is n NIST trceble stndrd prepred by Anlytics, C-14, S-35, nd P-32 re NIST trceble stndrds prepred by Amershm Blnk smples (urine smples which hve not been spiked with rdioctivity) re lso provided s cross-check smples In ddition, smples which re outside the bove rnges re provided, but this is usully not included in the forml intercomprison progrm The smples re nlyzed by ech prticipnt, nd the dt is sent to ISP for sttisticl nlyses Below re exmples of the types of sttisticl nlysedresults A report consisting of reltive bis dt for ech rdionuclide rnge tht hs been tested in the lst qurter (Fig l), nd FIG I RELATIVE BIAS CHART Performnce Evlution October December 1997 Alph Emitters t I X x v A X x d 4 h A B D C lb code E F

4 t n intercomprison of lbortory performnce for ech individul nlysis (Fig 2) These re published once per qurter FIG 2 HI-LO CHART Intercomprison Results PU-239 Jnury I 1 A C E F H I J lbcode multiple entries for single lb indicte split smple number of prticipting number of reported results incomplete, lost in process, or <MDA known vlue result men result stndrd devition result medin % devition men norml men % devition medin norml medin Note: The qurterly report is published three months fter the lst spike smpie to be included in the report hs been shipped to the service lbortory This is so tht the service lbortories hve time to process their smples, complete their nlyses, nd rely the dt to the ISP

5 Y Fecl Progrm: Prticiption in the fecl progrm is usully on qurterly bsis The smples re prepred using n rtificil mtrix' (see Tble 1) The mss of smple is typiclly 3g The preprtion of the fecl smples (btches) is three step process: The dry chemicls re mixed together in lrge continer nd retined f i e mount of wter need$ per btch is clculted nd this wter is spiked with known mount of rdioctivity from n ISP stndrd(s) A portion of the spiked wter (1Og) nd portion of the dry mixture (1 9g) re then combined in plstic bg, long with mesured mount of oleic cid (lg) to mke up smple This process is repeted for ech smple in the btch The plstic bg is het seled nd plced inside second bg which is lso het seled The fecl smples re tgged by ORNL Helth Physics for shipping to the vrious prticipnts in the progrm TABLE 1 CHEMICAL COMPOSITION OF SYNTHETIC FECAL SAMPLE Chemicl Component Clcium Crbonte 64 Ferric Ammonium Sulfte 3 Mgnesium Crbonte 4 Potssium Crbonte 55 Ammonium Dihydrogen Phosphte 133 Sodium Sulfte 24 Ammonium Chloride 3 Zinc Sulfide 1 Stnnous Chloride 2 Leucine 464 Lysine 331 Methionine 53 Threonine 132 Plmitic Acid 198 Steric Acid 132 Oleic Acid 1 Cellulose 265 Wter contining spike 1 I ~ The rdionuclides (spikes) used re ll NIST trceble stndrds prepred by NIST nd the subsequent primry, secondry nd tertiry stndrds prepred re done so using semi-micro blnce which hs been clibrted nd functionl checked using NIST trceble weights Below is list of the rdionuclides nd the spike levels tht re commonly used in the progrm:

6 U-nt: U-nt: PU-238: Pu-23 8 PU-239: Pu-239: Am-24 1: Am-24 1: Th-Nt: Th-Nt: 5-15 dpm/smple 1-5 dpdsmple <I dprdsmple 1-5 dpdsmple <I dpdsmple 1-5 dpdsmple < 1 dpdsmple 1-5 dpdsmple 1-5 dpdsmple 5-15 dpdsmple Blnk smples (fecl smples which hve not been spiked with rdioctivity) re lso provided s cross-check smples In ddition, smples outside the bove rnges my be provided, but this is usully not included in the forml intercomprison progrm The smples re nlyzed by ech prticipnt, nd the dt is sent to ISP for sttisticl nlyses The formt tht is used for sttisticl nlysis in the fecl progrm is identicl to tht used in the urine progrm (See Figs 1 nd 2) Whole Body Count Progrm: ' The ISP whole body count progrm begn Jnury 1993 The progrm provides Co-57, B-133, Y-88, Co-6, nd Cs-137 cross-check smples in O1M hydrochloric cid mtrix (five qurt bottles/smple set) which re inserted into identicl nthropomorphicphntoms A known mount of ctivity is initilly provided for ech rdionuclide to clibrte the detector for this phntom geometry The preprtion of the whole body count smples is two step process: The mount of wter needed per smple set is clculted nd this wter is spiked with known mount of rdioctivity fiom n ISP stndrd(s) (Ech trcer ddition is mde by mss nd the current testing rnge is 1-5 nci) A portion of the spiked wter (log) is then dded to ech of the five qurt bottles nd ech bottle is filled with 1M hydrochloric cid This process is repeted for ech prticipnt Ech of the bottles is plced inside plstic bg which is seled nd the whole is plced inside second bg which is lso seled The whole body count smples re tgged by ORNL Helth Physics for shipping to the vrious prticipnts in the progrm, Ech prticipnt receives its own individul phntom, which they keep s long s they continue to prticipte in the progrm Cross-check smples re sent to ech fcility every three months nd n nnul report is published t the end of the yer Additionl rdionuclides cn be dded t the request of ny of the prticipting fcilities All rdionuclides re NIST trceble stndrds Co-6 nd Cs-137 re prepred by NIST; Co-57, B-133, nd Y-88 re prepred by Amershm The formt tht is used for sttisticl nlysis in the whole-body count progrm is identicl to tht used in the urine progrm (See Figs 1 nd 2) Smple Lod: The expected smple lod for 1998 for ISP is s follows: Urinlysis Progrm: Fecl Progrm Whole body count Progrm 85-9 smples 15-2 smples 3-4 smple sets

7 :Advntges to prticiption in ORNL biossy intercomprison progrms: < r Prticiption in n estblished intercomprison (QC) progrm which hs positive recognition fiom the United Sttes DOE v Performnce criteri s estblished by pplicble Code of Federl Regultions (CFRs), other stndrds, nd DOE Orders Positive recognition by internl nd externl uditors Assurnce to workers nd public tht dose exposure redings re ccurte nd reproducible QA documenttion, Performnce Evlution Reports, fully-controlled ISP Procedures, nd NIST certifictes to ttest to performnce of lbortory A credible nd defensible externl QC progrm in the event of litigtion Intercomprison of nlysis cpbilities between ll mjor DOE contrctors Long nd short-term trending of nlysis performnce Current prticiption by ISP in DOE-sponsored Qulity Assurnce Progrm (QAP) nd Environmentl Protection performnce evlution progrms to c o n f m ccurcy of internl mesurements Future Plns: ISP is working to become Reference Lbortory for Biossy per ANSI N4223*, Mesurement nd Associted Instrumenttion Qulity Assurnce for Rdiobiossy Lbortories ISP is hoping to expnd into interntionl mrkets References 1 McLellnd, J A, R J Trub, nd D R Fisher 1988 Performnce TestineQf Rdiobiossv Lbortories: Vitro Mesurements, Finl ReDort PNL-649, Pcific Northwest Lbortory, Richlnd, Wshington 2 Associted Instrumenttion qulity Americn Ntionl Stndrds Institute (ANSI) 1996 Mesurement Assurnce for Rdiobiossv Lbortorii ANSI N , New York

8 M l111 llill l1ll1ll1li Publ Dte (11) Sponsor Code (18) uc Ctegory (I 9) /9966 vz& U - c76,rlfle,z DOE