Document 3J674mRoVOMp7koQkm8mKQ3wJ

Transportbetween environmentalccxnpartments (fugacitmyodeling)includedinlettefrrom Don Mackay on the air/wateprartitionicnogefficienctalculabons TRANSPORT BETWEEN ENVIRONMENTAL TEST SUBSTANCE COMPARTMENTS (FUGACITY) Identity:Perfluorooctanesulfonatmea;y alsobe referretdoas PFOS or FC-95. (1-Octanesulfonicacid,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8heptadecafluoro-p,otassium saltCAS # 2795-39-3) Remarks: NA METHOD Test (testtype): FugacityModeling Method: Level 1,11,and IIIEQC Computer Modeling Year completed: 1999 Remarks fieldforTest Conditions: Modelingconductedby Don Mackay of D. Mackay EnvironmentalResearch LimitedinPeterborough, OntarioCanada. The followingparameterswere used: K. = 0* Soil/wateprartitiocnoefficien(tUkg) = 2.4 Sediment/waterpartitiocnoefficien(tUkg) = 4.8 Fish/waterpartitiocnoefficien(tdimensionless=) 1000 Degradation halflife= 10 years See AirMater PartitioCnoeffic7ieRnotbust Summary RESULTS Level Iresultsindicatethe testsubstance,ifreleasedtowater,has a tendency to remain inwater (typicall8y0% would remain inwater and 20% would partitiotnosoil). Level 11resultsindicatethe same conclusionas forLevel 1.Advectionin water ispredictedto be the dominant process forremoval from the environmentwithdegradationbeing very slow The persistenceina regionisestimatedtobe controlledby the water residencetime. Level IIrIesultsindicate: 1 Dischargestoairwillresultinrapiddepositiontosoil(90%) and water(10%) 2) Dischargestosoilwilltend toremaininthesoil.Itslow sorptiontendency indicatetshemajorremoval pathway will be from run-offtowater. 3) Dischargestowaterwilltendto remaininthewater and the dominantremovalprocess(90%) willbe throughadvective flowwithlittsloerptiontosediments. CONCLUSIONS Don Mackay writes: "insummary, 'thisubstance'behaves much as one would expectofa stronglyioniccompound." "Ibelieveitisirhportantto measure realpartitiocnoefficienftosrinclusion inthemodel and perhaps refinethehalflives." These studiesare considereda "smallfirssttep". Submifter: 3M Company, EnvironmentalLaboratoryP,.O. Box 33331, St.Paul,Minnesota,55133 DATA QUALITY ReliabilityI:<Jimiscrhanking3. These studiesarepreliminaroynly. Furthercharacterizatioofnthe necessaryinputvaluesisneeded before more definitimvoedelingcan be conducted. REFERENCES Study summary lettefrrom Don Mackay, D. Mackay Environmental Research Limited,1664 Champlain Drive,Peterborough,Ontario,Canada K9LIN6 OTHER Lastchanged: 4/30/00 P 02 ,,DMER D. faackayEnvironmentalResearch Limhod 1604 ChamplainDrive PaterborrjugOhn,tario CaiiadA K9L IN6 -ti(e7l05)740-Pql*l GST Reg. *R-101420263 3M991 'ro: T)r.luchPurdy,3M I)r.Joy= SnidrCooper,BaLw-Be I)aarRk-,bwid JoYL-c Ireecivedthe"FlwrochemicalFugacityModeling PeAukemn&' statement.Itisgeracm]IY'm ag=nient withour expectationasnd we willdo our besttosatlqfyyour needs. lbe principal ProblemVA'I1Lmspcet.be gatberingtheinputdata-We = koV inclosecontactwithyou regardingthenwel developnmnt We obtainedfrom you thePL-'OSair-wateprartitionindgata.As I interpretthelabresultsthey estabU,.;haendiniticaolncentratioonf 50 mgg. in200 mL watbr thendi'sfflocfdf10 mL adiquots and analysedtheresidue.They thencalcahttedk-percentageof theoriginaPll-'O.pSresentwhich remainedinthebeakerunevaporated.'llmse-p=ent recomies- rangedfrom 136 to 105 with no real6vnd. IconcludethatthePFOS didnotevaporateto any mea=able extent.*Ms isa veryscnsitivncwthod ofnicasurinlgow sk-watcrpartitiocnocfficienmItcan be shown thatif waterand thosoluteevaporateequally(Le.thecontentsdo notchange inconqmsitionas would occawwithan amotrope) thenKAw or H isidenticaflorwater and thesolute..ForwaterHis approximatel2y400 Pa (a"roxinutely20-C)dwided by 55000 mol/d or 0.044Pa YW)nwlora KAw ofabout2 x 10-".PPOS must fts havea K,,,wconsiderabllyessthantW Le.lessthan2 x 10'. It is thus casentwlynon-,A)Iatif'rkomaqueoussohition'.nisisprobablybecauseofits iomdcDdm- Ilm simplewq)edientistoassignita K4w ofzero,Le.itisa type2 invokdk ch=Wcal inournorzwijcfature. We -didnwnpleEQC model runs usinga KAw of zert)a,nd partitio4nx)efEcientLslkg forsoil-water of2.4,qedimcnt-wateorf 4.8 and rlsh-wate(rdbncmionkss),of 1000. The din,ensionWs partiitc*)n coeffickatasrehigherby a &ctor convqwnding to thedem%ity.llm degradationhalfliveswem all.seat10yem. I attwh theLevelI,iiand ijTmsuiu. The TevelI msultsshow that?FOS has.aqtrungtendencyto remain inwater,i.e.typicall9y00/a with20% iisioil IU T-evcHl resultsshow an klenticadlistributio'nr.hemajorlossisby advectioninwaterwith p 03 onlyveryslow degmdatioil1"heoveral-lpeoisct= ina regionis controllebdy thowater romm-C The L@mi IIITouks Wx)w tiat:IfdlwluwgcdtoairitwHi rapidldyepositw soil,(900/o=)W wuw (IOOA). TrdisaWged tosoilitter0storomin therewith thenmjorlossbeingrun-oftfowaterbecauseof itslow sorptiontendency. Ifdischargetdowaterk tcn&itommain m'sokitioOnW issubjed torcmval by advwdvc flow (9(rlo-) 'rhereLeI.ftiks-urplk-itno sedirmnls. In summary, itbeham- much as one would expectof stwnglyioniccompouzxl I bclicwitisinvortanltomeasure realpartitiocnoefficienftosrinclusioinnthemodel aml perhapsrcfmc thehalffive& In thepm4ent rcgwatorycumate a substancewbdeh isso persistenits goingto conm undcrveryclosemutiny. 'Iwonder ifitispossibleto builda degradation weekTK= into the molecule? In conclusion,we are readyand willingtodo nwdcl%- atyo@w request.PL-a.%r@egardthisasjust a mmalllimtstop., Youn trldy Don Mwkay DM/=