Document 1yMBgjd9LKqrxY0963arEae8m

Larry R. Zobel.NED. NIPH StaffV;--LPres-,den-, and Medical Director 31NiMedical Department 3M Center,Building220-2E-O'-' 141 Box 33220 St.Paul.MN 55133-3220 651 733 5181 Office 651 733 5152 Facsimile April20, 2000 Dr. Oscar Hernandez US EPA/OPPT/CCD (7405) 401 M Street,SW Room E615B Washington, DC 20460 Dear Dr. Hernandez: M=l CUSTOMER PACKAGETRACKING I am writingto clarifiynformationcontainedinthetwo-generationreproduction studyon potassiumperfluorooctanesulfonatAe.reportofthisstudywas submitted on February 15, 2000 as a supplementtotheTSCA Section8(e)Notice of9/14/98. That noticehad been filedmidway throughthe studywhen we became aware of Fl pup mortalityatthehighesttwo dosesinthestudy(1.6and 3.2mg/kg/d). The studywas conducted %kithperfluorooctanesulfonagtieven by oralgavage atfour doses,0.1,0.4,1.6and 3.2 mg/kg/d. Following the pup mortalityseen inthe 1.6 and 3.2 mg/kg/day dose groups,onlythe 0.1 and 0.4 mglkg/day doses groups were continued intothe second generation. Language inthe reportindicatedthatF2 pup viabilitwyas affectedinthe 0.4 mgikg/day dose group.This isnot the case. Attached isan amended reportfrom the laboratoryperformingthe study,Primedica,Argus Division.The amended language clearlystatesthattherewere no toxicologicalliymportanteffectson pup survivalor grov-thatthehighestdosage tested0.4 mgikg/day. I have attachedtable E20 foryour reference.Itshows no significandtifferencebsetween the vehicle controlgroup and the0.4 mg/kg/day dose group fornumber of stillbor(n0.3+/-0.6 and 0.5 +/-0.9),pup viabilit(y97.1% and 96.2%) or number of pups survivingper litterp,recullingo,n day 4 (13.7+/-3.3and 13.8+/-2.4). Dr. Marv Case, Directorof Toxicologyat3M and Dr. Mildred Christianand Dr. Raymond York ofPrimedica Argus prepareda paperforpublicationthatreflects thisinterpretatioTnh.ispaper isstilulnder internarleview. Dr. John (Jack)Moore, formerlyof EPA and now a consultantinToxicology,has alsoreviewed the full reportand agreeswith thisinterpretation. I requestthatyou treattheattachedreportas supercedingthe earliereport.You willnotethatthe studyreportsubmittedasfollowup tothe 8e had only summary data tables.The enclosedreportincludesallof the datatables,individualas well as summary. Dr.OscarHernandez Apri2l0,2000 Page 2 Also enclosedisan analyticreportthatgivestheperfluorcoctanesulfonate concentrationisnliverand serum samplescollectefdrom selectedanimalsinthe two-generationreproductiosntudy.The serum and liveranalyticadlataincludedin thereportoffera limitedunderstandingb,ecauseof thetimingand limitednumber of samples,of thepharmacokinetieosf perfluorooctanesulfonate. Two additionasltudieshave been undertakento developan understandingof the dispositioonf perfluorooctanesulfondautreinggestatioannd lactationI.nthe first of thesestudiesp,otassiumperfluorooctanesulfonawtaes administeredby gavage up to thepointof mating,and dispositioonf thebody burden in dams to pups was followedduringgestation.Inthesecondstudy,dosingcontinuedthroughgestation and lactationa,nd dispositiownas followedthroughlactationT.he in-lifaespectsof thesestudiesarecomplete,and reportsareenclosed.Protocolsfortheanalytical work associatedwiththesetwo studiesisenclosed.Finalanalyticarleportsshould be availablweithinthreemonths. A complete crossfosterinsgtudywas alsodone. Thisstudywas done withonly two groups,a controland a group dosedat 1.6mg/kg/day. Thisdose levelhad minimal effecton thedams butproducedneonatalmortalityintheoriginatlwo generationstudy.The cross-fosterisntgudyshows thatneonatalpup mortalityis relatedto exposureof pups iiiuteroduringgestationa,lthoughthereappearsto be a contributiotno themortalityfrom thetreatedams ifpups were alsoexposed in ittero.A copy of thefinalreportisenclosed. Two ancillarryeportsareassociatewdiththecross-fosterisntgudy.In thefirst, serum perfluorooctanesulfonalteevelsindams and pups were monitoredatlactation days 14 and 21 or 22. Thisreportdemonstratesthatpups areexposed in uteroand can be exposed viamilk. Litterwsithexposurein uteroand viamilk from treated foster-damshave serum valuesapproximatingfoster-damserum valueson days 21 or 22 of lactationL.itterwshich were born ofuntreateddams but cross-fosteretdo treateddams have serum concentrationrsoughlyone-thirdof foster-damvaluesat theend of lactationL.itterbsorn oftreateddams but cross-fosteretdo untreated dams have serum valuesof approximatelyhalftheirbirthdams attheend of lactationT.he untreatedfostedrams arefound toacquiresingle-digpiptm levelsof perfluorooctanesulfonaitnetheirserum,presumablyfrom exposureto pup urine and feces. Dr. Oscar Hernandez April20,2000 Page 3 The second ancillarryeporttothecross-fosterisntgudyrelatetso electron microscopyconductedon lungand livertissueof pups culledshortlyafterbirth. Lung tissuewas examined forpossibleffectosf perfluorooctanesulfonaotne pulmonary surfactanptroduction.Therewas no differencbeetween controland exposed pups with regardtolungarchitecturaend thepresenceof lamellarbodiesin Type IIpneumocytes. Surfactanptroductionappearednormal. Since perfluorooctanesulfonactaeusesperoxisomeproliferatiionrodents,livertissue was examined forthepresenceof peroxisomes.Pups exposed inuterowere found to have a two tothreefoldincreaseinperoxisomes.Copies of bothreportsare enclosed. An additionaflollow-upstudyisbeingplannedtoexplorethepossibleroleof decreasesincholesteroaltbirthas a mechanism forreducedpup viabilityI.thas been shown (Levinet.al.,1989)thatratpupsundergoa burstof steroidsynthesis activitpyriortobirthfollowedby a periodofmuch reducedsynthesifsollowing birth(perhapsdue tothepresenceofexogenouscholesterodluringlactation)l.iNlG CoA reductaseand I-IMG CoA synthasemRNAs arehighestduringlatefetallife and undergo a precipitourseductionimmediatelyafterparturitionH.arb et.al. showed thatfluvastatiann,HMG CoA reductaseinhibitomrarketed asLescolfor hypercholesterolemiiaf,administeredpriortoand duringgestationc,ausesneonatal mortality.The mortalitwyas preventedby co-adniinistratoifonmevalonate,the productofthe reactioncatalyzedby FMG CoA reductase. Perfluorooctanesulfonarteeducesserum cholesteroiln laboratoraynimalsand is reportedto reduceactivitoyfHMG CoA reductase(Haughom and Spydevold, 1992).Our plannedstudywould testthehypothesisthattheneonatalmortality observedinthehighdose groupsof thetwo-generationperfluorooctanesulfonate studyisdue tothereductionincholesteroslynthesidsue to reducedHN4G CoA reductaseactivity.Thiswould be done by attemptingmevalonaterescue,similarto thefluvastatisntudy.We willalsoattemptrescuewith cholesterol. Two additionaolbjectiveasrebeingdesignedintotheplannedstudy.The first would be to more preciseldyefinea NOEL and LOEL forpup mortalityby testing doses between 0.4and 1.6mg/kg/day. The second istoobtainadditional pharmacokineticdata. Dr. Oscar Hernandez April20,2000 Page 4 Human infantsdo notundergoa similarprecipitoudsrop incholesteroslynthesisat birth(Levinet.al.,1989).Establishinrgeducedcholesteroslynthesisas a mechanism of actionwould have significainmtplicationwshen assessingrisk associatedwiththefindingsinthetwo-generatiosntudy.The plannedstudyis currentlyundernegotiatiownitha contractlaboratoryW.e willsharetheprotocol and expectedcompletiondatewithyou when theyareavailable. We arelookingforwardtodiscussionbsetween our scientisatnsd agency scientists abouttheinformationwe have submittedand continuetosubmiton perfluorooctanesulfonate. Sincerely, LarryR. Zobel,MD NTH StaffVice Presiden&t MedicalDirector c: Dr.CharlesAuer,DirectorChemicalControlDivision(noattachments) References: Harb, R.V.,Hartman,H.A.,and Cox, R.H. (1994),Preventionoffluvastatin inducedtoxicitym,ortalitya,nd cardiacmyopathy inpregnantratsby mevalonic acidsupplementation.TeratoloSy5,0, 19-26 Haughom, B. and Spydevold,0. (1992),The mechanism underlyingthe hyperlipemiceffectofperfluorooctanoaiccid(PFOA), perfluorooctanseulphonic acid(PFOS) and clofibriaccid.BiochimicaetBiophysicaActa,1128,65-72. Levin,M.S.,PittA,.J.A.,Schwartz,A.L.,Edwards,P.A.and Gordon, J.1.(1989), Developmental changes intheexpressionof genes involvedincholesterol biosynthesiasnd lipidtransporitnhuman and ratfetaland neonatallivers. Biochimica etBiophysicaActa, 1003,293-300. hments Protocol418-008 Combined oral(gavage)fertilitdye,velopmentaland perinatal/postnarteaplroductiotnoxicitsytudyofPFOS inrats(Sponsor'sstudy number: 6295.9),TableE20, 1-3. Harb,R.V.,Hartman,H.A.,and Cox, R.H. (1994),Preventionoffluvastatin inducedtoxicitym,ortalitya,nd cardiacmyopathy inpregnantratsby mevalonic acidsupplementation.TeratoloSy5,0, 19-26 Haughom, B. and Spydevold,0. (1992),The mechanism underlyingthe hyperlipemiceffectofperfluorooctanoaicid(PFOA), perfluorooctanseulphonic acid(PFOS) and clofibriaccid.BiochimicaetBiophysicaActa,1128,65-72. Levin,M.S.,PittA,.J.A.,Schwartz,A.L.,Edwards,P.A.and Gordon, J.I(.1989), Developmentalchanges intheexpressionofgenes involvedincholesterol biosynthesiasnd lipidtransporitnhuman and ratfetaland neonatallivers. BiochimicaetBiophysicaActa,1003,293-300. FinalReportProtocol418-013 Oral(Gavage)PharmacokineticStudyof PFOS in Rats (Sponsor'sstudynumber: T-6295.12),June 24, 1999 ProtocolFACT-TOX- I10 Oral(Gavage)PharmacokineticStudy of PFOS inRats, Protocol,June 8, 1999 FinalReportProtocol418-015 Oral(Gavage)PharmacokineticRecovery Study of PFOS inRats(Sponsor'studynumber: T-6295.14),July23, 1999 ProtocolFACT-TOX- IIIOral(Gavage)PharmacokinetiRcecovery Studyof PFOS inRats,ProtocolJ,une 8, 1999 Summary PFOS Rat Two-GenerationReproductionStudy(Studynumbers: 3M T-6295.9,Argus 418-008[in-lifeF]A,CT-TOX-012 [analytical]) Report Amendment 1,13 April2000,Protocol418-008 (Sponsor'studynumber: 6295.9)Combined Oral(Gavage)FertilitDye,velopmentaland Perinatal/Postnatal ReproductionToxicityStudyof PFOS in Rats,FinalReport AnalyticalLaboratoryReport on theDeterminationof thePresenceand ConcentrationofPotassiumPerfluorooctanesulfon(aCtAeS Number: 2759-39-3) inthe Serum and Liverof Sprague-Dawleyg RatsExposed toPFOS viaGavage, LaboratoryReportNo. <U2006>, RequestorProjectNo. <3M TOX 6295.9>, October 27, 1999 InterofficMeemo from Tom KestnertoLeo Gehlhoff,"FluorochemicalIsomer Distributionby 19F-NMR Spectroscopy,December 1, 1997 FinalReport Protocol418-008 Combined Oral (Gavage) FertilityD,evelopmental and Perinatal/PostnataRleproduction ToxicityStudy of PFOS in Rats (Sponsor's study number 6295.9, June 10, 1999 Summary PFOS Rat Cross-Fostefing(Study numbers: 3M T-6295.13, Argus 418014) FinalReport Protocol418-014, Oral (Gavage) Cross-FostefingStudy of PFOS in Rats (Sponsor'sstudy number: T-6295.13),July 23, 1999 AnalyticalLaboratory Report on theDetermination of thePresence and Concentrationof Perfluorooctanesulfonat(ePFOS) (CAS Number: 2759-39-3) in the Serum of Sprague-Dawley(g Rats Exposed to Potassium Perfluorooetanesulfonatevia Gavage, Laboratory Report No. U2779, Requestor ProjectNo. 3M Tox 6295.13, June 10,1999