Document 7MVj99yGB5DY0zQGGdm5YroZe

SiLafrryicRe. Zporbeesle,nMD MPI nd Medal itor 3MMedical Deparment 5StMPCaeunlt,erN,NBuSiSld1i4n8g.10020200-06-05 665811775333 55118512 OFfafs June 29,2005 SIM se stat . Designated Federal Officer U.S. EPA Science Advisory Board Via e-mail: shallal.subair@geopav Re: PFOA Review Panel - Draft Report Dear Dr. Shallal: Tam writing in response to the PFOAReview Panel's June 27, 2005 releaseof its draft report regarding EPA's draft risk assessment forPFOA. Since written comments are. due today and time does not permit acomprehensive discussion, 1 would like to highlight two issues: discussion ofthe human data, and the cancerdescriptor. Human Data 3M's multiple mortality studies and nearly 30 yearsof medical surveillancedata on PFOA manufacturingworkers provide evidenceofthe lackofadverse effects in humans. `We are surprisedto see thePanel'sreference, in response to charge question 5, to "positive results"and "certain adverse health effects (cancer, heartdisease, blood chemisries)." This Statement is made with no references, no specificity, and no context. We believe itis contraryto the weightofevidence. Table 1 belowprovides data fromthe most recent retrospective cohortmortality studies conducted at the 3M Cottage Groveand Decatur fucilities(Alexander2001a; 2001b)." The Alexander2001a studied workers at 3M'sCottage Grove plant where PFOA. `was manufactured forover forty years. We are not awareofmortality data on other PFOAexposed cohorts June 29, 2005, Page 2 Further, the data do not supporta findingthat heart disease is apotential adverse: healtheffectofPFOA, also illustrated in Table 1. The "Low"exposure group in this study would be expected to have seraconcentrationsat least an orderofmagnitude higher than the 90TM percentile concentration used in the EPA draft risk assessment. In summary,theconclusory statements in the draft report are not supported by the epidemiological data. We urge the Panelto revise the statementordocument ts validity. More detail isprovided inourcommentsofApril 18, 2005. Descriptorof CarcinogenPotential We knowthe Panel has struggled with fitting the PFOA dataset into the EPA definitions forthedescriptors. As noted above, thehumandata do not supporta conclusion of humancancer risk. The mammary tumors have also now been addressed by a Pathology `Working Groupreport findingthat `the incidenceof mammary gland neoplasms in the study wasnotaffected by chronicdietary administration ofPFOA." (See letter dated June 27, 2005 submitting PWG report). We urge the pan to again considerthe proper descriptor in Tightofthe conclusionofthe Pathology Working Group. The authorofthis report will be: available forquestions duringthe July 6teleconference. Finally,the initial working draft circulated at the Panel's February meetingclearly articulated that the Panel doesnot agree with the notion that cancer in humans is more likely than not. We urge the Panel to include this statement in the report. The statements on pages 3 and 17 in the current draft report do not adequately convey that concept. Respectfully submitted, Larry Zobel, M.D, MPH. StallVice President and Medical Director sess: :izzsigi ge o 3 gifs teil i peizes rrrrrl:i 1 IAeEaREsEB ferred Hgg ii B; 14| e-evvegsz Eo meween2~ i i: 2: 3 i 3 55 i dg = He EERE sjiiggsraeeun g2 5 iHfI f1iiid tiideSs giulHf BHF srras: snaase 5 1 i i 3ooEEIas 53rd2 sIiii i i: TE 2oecem 22d f E53 ii i: : Tec EgEgiEfl|Etfe2a:3t cH Bip 0 ii Taree sippyERbyE