Document 2qoqxzzEDeGnBQxggpgEM6vvR

SOIL ADSORPTION TEST SUBSTANCE Identity: N-methylperfluorooctane sulfonamidoethanol; may also be referred to as N-MeFOSE Alcohol, FC-790, or FM-3925. (1Octanesulfonamide, N-methyl-1,1,2,2,3,3,4.4,6,5,6,6,7,7,8.8,8heptadecafluoro-N-(2-hydroxyethyi)-, CAS # 24448-09.7) Remarks: Material is an off-white, waxy solid. Sample purity and lot number were not recorded. METHOD Method: ~~ Adsorption-desorpion studies developed using procedures described by Davidson, 1976 and Hamaker, 1975. YGeLaPr((YsItNu)d:y pNeorformed): 1979 Statistical methods: Statistical analysis and plotting of the data was done with the MINITAB package of the 3M TRAC computer service. Temperature: 16-19C during the 24-hours of wrist-action shaker exposure. Stock and test solution preparation: The stock solution used was an aliquot from the 24-hour sample taken during the water solubility study on N-MeFOSE Alcohol. This solution was prepared by the Vieth method and gave a concentrationof 2.16 mg/L. Test solutions were made by diluting aliquots of the stock solution. 5R7em%asraknsd,fi3el6d%: silt, T7h%e cBlrailyl, s2a.n5d%yolrogaamniscoimlawttaesr,ch2a.r2a%ctoerrgiazneidcacsarhbaovni,ng swiotlhutpioHns6.o5f aNn-dMceaFtOioSnEexalcchoahnoglewecarpeacpirteypaorfe1d5.i3n dmeeiqo/ni1z0e0d gw.atSetraantdard cmogn/cLe,ntarnadti0o.n0s2o2fm2g.l1L6. mgFo/rLt,y 1m.i21ofmeg/aLc,h 0s.o6l9ut1iomng/wLa,s0s.h3a8k9emng/wiLt,h05.2g1r6am samples of the soil In a 50 mi glass centrifuge tubes for 24 hours in duplicate on a wrist shaker at room temperature (16-19C). Desorption extractions were performed with deionized water after the adsorption phase of the experiment. The samples from the adsorption and desorption experiments were centrifuged individually at 3000 rpm for 30 minutes, and each supernatant solution was decanted off into glass sample vials. Supematant solutions were analyzed by extracting with ethyl acetate and running GC. 006541 RESULTS K: 7 Kee: 3,500 Remarks field: The linear shape of the adsorption isotherm indicated that N-MeFOSE alcohol adsorption on soil would be independent of concentration in solution. * The study report had calculated using the formula: Koc = 100 K/% organic carbon. CONCLUSIONS `The study substance is expected to exhibit low mobility in the kind of soil tested. `Submitter: 3M Company, Environmental Laboratory, P.O. Box 33331, St. Paul, Minnesota, 55133 DATA QUALITY Reliability: Kiimisch ranking 3. Study is using an inaccurate solubility vTahleueanaanlydtitchael pmuertithyodofolthoegytewsat ssunbosttvaanlciedaitsedn,otthsuefrfeifcoireenttlhyecrhearisacntoerwiazeyd.to evaluate the accuracy of the reported analytical results. It was noted in the report that a high percentage of FM 3925 was adsorbed onto the glass used in the experiment. No attempt was made to correct for this loss of tpeesrtpasruibnsgtaanscaetuinrattheedcsaollcuutliaotniownosuolfdsdoirspptrioopnotrotisoonila.teTlyhediVsiseotlhveMtehtehomdoroef soluble components of N-MeFOSE alcohol which is not a pure material. The study was not performed in duplicate, and the soil was not analyzed to verify the amount remaining. Additionally, the following are summarized comments made by Professor Stephen Boyd, Michigan State University: Use of oven dried soils not recommended. Should be air-dried and characterized for moisture content. iUtsceauosfedseitohneiszoeldl twoatdeirspfeorrsdee.soUrspetidoinluetxepCearCilmze.nts is not recommended as Ethyl acetate extraction not validated. Did not establish that the sorption isotherm is linear. 006542 There is no evidence for electrostatic forces being involved in soil binding `of FM 3925. REFERENCES 3M Technical Report "Adsorption of FM-3925 on Soil." S.K. Welsh and C.H. Schrandt, Project 9970612631 Fate of Fluorochemicals, Report No. 013, March 22, 1979. Reviewof Technical Report Summary. Adsoprtion of FM 3325 on Soil. Professor Stephen A. Boyd, Michigan State University, May 19, 1993. OTHER Last changed: 5/17/00 006543 A`WtetlaschheadndarCeHc.omSmcehrnatnsdto,nPtrhoeje3ctM9T9e7c0hn6i1c2a6l3R1eFpaotreto"fAFdlsuoorrpotcihoenmiocfaFlMs,-3R9ep2o5rtonNoSo.il.13,SXMa.r. 22, 1979" made by Professor Stephen A. Boyd, Michigan State University, dated May 19, 1993 006544 Review of Technical Report Summary Adsorption of FM 3925 on Soil Materials and Methods 1dewteorumlidnantoitonr(eocvoemnmdernydingo)vetno gdertyitnhge smooiilss.tureUsceontaierntd.ried soils and do a separate moisture Solubility was determined earlier as 2.3 ppm. Desorption experiments should probably use dilute CaCl solutions instead of deionized water which will cause the soil to disperse. The extraction procedure described utilizing ethyl acetate needs validation. The percent recoveries of FM 3925 from standard solutions should be reported. `The sorption isotherm only extends to an equilibrium concentration of about 0.22 ppm which is 10 times lowerthan the water solubility (S,) ofFM 3925. The isotherm needs to be extended 100.55, or greater, way to establish the i.e., equilibrium linearity of the aqueous concentrations approaching S,.. isotherm. I'm again not certain of the This is the only meaning of the desorption experiments. I would not draw any major conclusions regarding mobility from those data. 3T9h2e5r.e iTshaibssoilsuptuerlye cnoonjeevcitduerneceanfdoralelmeocsttrocsetrattaiicnlfyorwcreosnbge.ingThienvoonllvyedelienctsrooisltabtiincdmiengchoafniFsMm would be to protonate the N of FM 3925 to createa cationic species that could interact with negatively charged sites indicate the likelihood of in soil that. clays and The linear soil organic matter. isotherms (if they are The pKa of FM 3925 in fact linear) suggest wsooluultde + partitioning not adsorption by electrostatic forces. Solute partitioning involves dissolution ofFM . 3925 in amorphous soil organic matter. The magnitudeofthe sorption coefficient (K.,) depends 5 on the relative solubilityofFM 3925 in soil organic matter and water. The K,, values reported for FM 3925 is 3500 (100 K/% organic carbon = 100 x 330/2.2). The K value reported was 77 so it should be: K,, = 100 x 77/2.2 = 3500. This may be a reasonable value although it `would be easier to evaluateifthe Ky was known. Gareen and Katickhoff (1990, Pesticides in tAhmeerSiocial,EMnavdiirosnomne,ntW,I)Chgaipvetetrhe4,emSpoirrpitciaolneqEusattiimoant:es for Modeling, Soil Science Society of Log K,. = -0.68 log S (ug/ml) x 4.273 which using the solubilityof2.3 yields a predicted K,, of about 10,000 so its at least close. Equations like this using solubilitiesofsolids thathaven't been corrected for melting point, i.e., converted to supercooled liquid solubilities, give pretty rough estimates. I think you could get a better estimate if you knew Ko. . 006545 Recommendations 1. Measure the octanol water partition coefficient, relate measured to Ke via Chiou's equation: log Ko. = 0.862 log S, + 0.710 remembering S, of a solid should be converted to supercooled liquid solubility if the melting point is much over 100C. 2. iEsxottehnedrmraenxgpeeriomfenetqsu.iliTbersitumotaheqruesoouilss concentrations to evaluate: to approach S, in the sorption 3. Determine the pKa of FM 3925 to evaluate likelihood of electrostatic interactions. 006546 .3m . Form 6747-11:4 TECHNICAL REPORT SUMMARY TO: TECHNICAL COMMUNICATIONS CENTER -- 201.20 Important -- i ports itedonbothsides fpapersndtocopies 0 TCC.) 5 3/22/79 ar Environmental Laboratory (EE Pe 0S53E5 Fate of Fluorochemicals > AN. Holter Adsorption of FM-3925 on Soil 013 Stephen K)Welshd C. fe Schrand s1050 073583, 113152 i ssconmvh QO connie Tonner | "hESETED a [P=T-- CRT GRIT Das Sate 5Fluoorrocchemical To obtain an indication of FM-3925 mobility in a sandy loam soil. ETAABS AACCTT, 000aTorTThle ae iinos Svoaed 7 TeeomariGoon To obtain an indication of mbility Gf FU-3925 in a sandy loam soll, adsorption/desorption experiments similar to those of Davidson, b1e976i,mmaonbdiloefbHaasmeadkeorn, an197a5d,sowreprteionconcdouecftfeidc.ientFMo-3f92757; walsessjudtgheadn to . S1o5%lwdbeisloircpytioofnowniltyh 2.t1h6reemg/dle.sorption extractions; and water -- om-- e 00547 FN-3925; -2- 3/22/79 coNcLUSTONS Tchoeeffaidcsioernptt,iondescoorepftfiiocnienctharfaocrteFrNi-s3t9i2c5s,wasand77.wateCronssiodleurbiilnigtyt,heFMa-d3s9o2r5ptiwoonuld be judged immobile in the sandy loam soil used in this study. INTRODUCTION Aosf aFNp-a3r9t25ofinthseanFdaytelooafn Fslouilorowcashemdiecsairlesd.ProAjedcsto,rptainoni-nddeiscoartpitoinonofemxopbeirlimietnyts c(aanftperrovDaivdiedstohni,s 1i9n7d6icaantdioHnamoafkemro,bil1i9t7y5.) alTohnigs waiptphrowaactherissuosleudbilbiytythedatUaSEPA in pesticide registration requirements. MATERIALS AND METHODS D3u6p%liscialtt,e 5a-ngd s7%amcpllaeys, owfitohven2.-5d%rieodrga(n1i0c3maC.t)terB,ril2l.2%saonrdgyanliocamcasrobioln,(5w7i%thsanpdH, 6.5 and CEC of 15.3 meg/100 g) were shaken with 40 ml of solution in 50 ml glass c(e16n-t1r9ifugC.e).tubeGslasfsortu2b4eshouwresreounseadwrbiescta-uascetiiotnwasshakbeelrieavtedr,oombasteedmpeornatpurrieor peoxlpyereitehnyclee,nethtautbesg.lass would adsorb less FM-3925 than polypropylene or SSoolluuttiioonnswwaesrethmead2e4-bhyoudrilsuatmipnlge afrosmtoctkhesosleuctoinodnVoifeththestcuhdeymiocfalw.aterThesolsutboiclkity 0(.46692169m-g5/31,and0.3488927m-g8/)1., 0C.o2n1c6enngt/r1a,tioannsd o0f.02F2M-m3g9/2l5 w(e1r0e0%,2.1566%,mg/5l2,%, 1.1281%,ng1/01%,, and 1% of Stock). i v wAifttherdesihoankiiznegd-thweateirn,ititahle ssaomlpulteisonsw,ereascweenltlriafsugetdheatthr3e0e00derspomrpftoiron30emxitnruatcetsi,ons and cach supernatant solution was decanted off into glass sample vials. Awfatserputremionvtiongthethetub4e0smlforofthieniftiiarlstsdoelsuotripotniofnorexatnraalcystiiso,n. 40SmilmiloafrlDyI,wattheer second and third desorption extractions were conducted. The samples, now in glass sample vials, were analyzed by first adding 5 ml oonf aBuGredniicek aVnodrtJeaxckMsioxnerdiatstimlalxeidmminspgleaesdsfeotrhy3l0 asecceotnadtse, toanedacchenvtirailf,ugmiinxginatg 2d5r0a0wnponfffwoirth10amitnruatnessf.er Tphiepetethtyolaaccleetaantevilaaylearnd(atbhoeunt t1woml)mowraesetxhternactions wienrgeasconabdouvcet,edawnidththe2 nelthyolf eatcheytlateaceltaayteers efarcohm efaoclhlowseudccbeyssmiviexinegxtarnadcticoenntrifugwaenrdethceomebxitnreadctisn wtehreesaemveapocrlaetanedvitaol.nearThednr,yne1s5smlwndoefrentihytlrogaecnetaatned wtahsenatdrdeadn,sAffetrerredtrtoan4s-fnelrrcionngcetontrauattoomrattiucbessamapnldebrrovuiaglhst, upgastoch1rmolmawtiotghramesthywlereacertuante. oinnclduudpeldi:cate S5-ul injections of the extracts. GC equipment and conditions 006548 . F-53925 -5- 3/22/79 CChorloummaso-gb6' W-xAW1;/8"Chr0.oDm.atosgtgaianplhe-sHsP s57t1e3e,l, Ni10%63CaDertbeocwtaoxr;20MConondit6i0o/n8s0 m-esIhnject P17o5rg 2f0o0r 1C6.,minD.e,tetchteonr 3w0p0toC.2,30FloC.w a3t5 c3o2f/mmiinn.. Arf/oCrH,4 9mi5n/.5, Oven temp. SotfattihsetiScMaTlRAaCnaclyosmipsutaenrdspelrvoitctei.ng of the data was done with the MINITAB package RESANUD DILSCUTSSISON ArdesmoorvpetdiofnrodmatsaoluftoironFMb-y392t5hearseoilgiv(eCnoliunmTAC)BLEwasI. 83-T9h0e%amoofunttheofiniFtMi-a3l925amount at the various starting (initial) concentrations. Eaqmuoiunltisbriaudmsorcboendcenotnratthieonssoilin (sxo/ml)utiionnyg(C)FN-in392m5g/lperaregrsahmowsnoilinarCeolsuhmownB, inand ~ wCaosluxm/mF.= -T1h.e7+reg77rCe,ssisoontehqatuattihoenadosfortphetioandsocropetfifiocnieinsto,thKe,rnwasshow77n. inThFeIGUlRiEnea1r Wsohualpde bOef tihnedepaednsdoernpttioonf ciosnoctehnetrrnatiinodnicaitnedsoltuhtaitonF.M-39T2h5e haidgshorppetricoenntoangesoialdsorbed and the relatively high adsorption coefficient indicated that FM-3925 would be immobile in this sandy loan soil. DinesoFrIGpUtRiEon1.datOaFartehegaimvoeunntisn TiAnBiLtEialIIl,yanaddstohrebeddesonorptthieonsoiils,othleersmss thaarne s1h5o%wn wTahsisrsepmaolvledabmyounttheofthdreeesordpetsioornptiisonaelxsotraschtoiwonnsbywitthhe wfaatirelry(hToArBiLzEonItI,alCsolloupmesI). Tohfistheverdyesosrmpaltlionamoiusnottheorfnsdescoormpptairoend wwaisthanthoethselropiendoifcattihoenadosfortphetioinmmoibsoitlhietrym. of F-3925. i . Tohfe PMl-a3rg9e25antoounstoiladpsaorrtbiecdleasndbytheinstmearlmlolaemcouulnatr dienstoerrbaectdiosnusggeisntvsolvsitnrgongelbeicntrdoi:ng 53 static forces. The adsorption coefficient based on soil organic carbon, K_, for FM-3025 would be 3,500 (100 K/% organic carbon = 100x330/2.2). Comparedith K__ values for aisseqluietcetehdigghrouapndofispeasntoitchiedresinadnidcaottihoenroffluloowrocmhoebmiilciatlys of(TFAMB-L3E92I5%.f), 3,500 TFhMe-s3e925ads(o2r.p16tiomng/1a)n,d dpreosvoirdpetiognooddateav,ideanlcoengtwhiatthFMth-e392l5owwwoautledrhsaovleubvielriytyloowf mobility in the sandy loam soil used in this study. Itnhata 5c3o%ntorfolt"heusFiMn-3g92t5hewafsu.lrl-msotvreedn'gtfhrosmtsooclkutsioolnuti(o1n00axnd(n2o.1s6o-i1l.,007i)t/2w,a1s6)f,ound being adsorbed on the glass tubes (TABLE IV). Of the amount adsorbed, 20% t(i1o00nsxwi(t4h6.D1I-3w7a.t1e)/r46(.t1h)e wdaessorsputbisoenqueinstoltyhedremsoisrbesdhowinn itnhreFeIGdUReEsor2p).tion extrac- 006549 F-39025 -a- 3/22/79 Trheimsovecdontfrroolm esoxlpuetriiomnent(TiAnBLdEicaI,tedCotlhuamt Ca)cwoanssibdeeiranbgleadpsoorrtbieodnonofthteheglFaMs-s3925 ritatwhoeurldthbaen onnecetshsearsoyilt.o co.Innduocrtdersuctho ccoonrtrreocltsfoatr tehaicsh ionf tthhee cianlictuilaalticoonns-, cexepnetrriamteinotn,s. itWhpirloebabsluychwoaulcdonr'rteccthiaonngewoutlhde make it truly conclusions. a "soil adsorption" The removed "by b5e011l"owweorulmdovibenglotwheer,adsanodrpttihoenamiosuontthseronndotwhne,sobiult t(hTeABaLEdsoI,rptCioolnumcoeF)ffwiociuelndt n(atyhebeslospheifotefdtdhoewniswoitthehronu)t mchaaynngoitngchtahenged.esorLpitkieownisec,oeftfheicideenstosr.ptioAnlsoi,sostihenrcnes tchaerrbeonisconnotecnatrboofntihen tsohiel,glaKs_s,, tshheouladdsorrepmtaiinonthceoefsfamiec.ient based on organic TERS c - Concentration of chemical in solution at equilibrium x/m - Concentration of chemical adsorbed on soil at equilibrium B - Coefficient of determination K - Adsorption coefficient ' Ky. - Adsorption coefficient based on soil organic carbon content REFERENCES v Davidson, J. M., et al, 1975, Use of Soil Parameters for Describing Pesticide . Movement Through Soils, USEPA, EPA-660-2/75-009. " DavidsoSno,ilsJ.,"M.P,res1e9n76t,ed"VatertSiycmaplosMiouvmemoenntNomabnidolDoigsitcrailbutTiroannspoofrtOrgaanndicTsranisnSftoarnmdaatridosn,GoafitPhoelrlsutbaunrtgs,oWnD,MLaned y1nd1-1RE3te,T1,976a.t Nations Foren of HamakerC,hemJi.caWl.s,, 1H9u75m,an"HIenatletrhpreatnadtitohne EonfviSrooinlmeLneta,chiAngCoElxlpeectriiomnentosf,"Dowin Scientific Papers, Vol. I, Dow Chemical USA, Midland, MI 48640. HamakerI,h tJ.heW.SoialndEnJ.virM.onpTohnotmspsonC,. A1.972I.. Go"rAidnsgorpatndioJn." Wi.n O(rgaeniRRmcRerdChesmic) als Mazcel Dekker, Inc., NY. SKW/CHS/ cen 006550 TABLE FM-3925 ADSORPTION DATA A InCitoinacl. FmMg/31925 2.160 (100%) 1.210 (56%) 0.691 (328) 0.389 (18%) 0.216 (10%) 0.022 (1%) B Equci,l.ng/C1onc., 0.2135 + 0.0516 0.1455 + 0.0106 0.0940 + 0.0156 0.0490 + 0.0042 0.0570 + 0.0028 * c Soil % RGelmaosvsedTbubyes AABB x 100 50 8 86 87 83 0 In TIontiatlialFMSo3l9'2n5, mg (A x 0.04 liters) 0.0864 0.0484 0.0276 0.0156 0.0086 E F SToolt'anlatFMEq3u9i2l5.,Inmg oFnMSo3i9l2,5 Axd/smo,rbuegd/g (B x 0.04 liters) (0-E 10Y5g) 5 0.00854 15.57 ' 0.00582 8.52 0.00376 - 4.78 0.00196 2.72 0.00148 1.43 "Aalnld tsahmepsleesweraet tnhoet i1n%clinuidteidalinctohnecenctarlactuiloatniownesr.e below the detectable limit, 006551 TABLE II FN-3925 DESORPTION ISOTHERM DATA A EqSuoillu.tioCno,nc.C, in (Tamblge/11, Colum B 0.2135 +0.0516 0.1455 + 0.0106 0.0940 + 0.0156 0.0490 + 0.0042 0.0370 + 0.0028 B EFqiurislt. DCeosnocr.ptiionn mg/1 0.1160 +0.0057 0.0585 + 0.0035 0.0310 +0.0057 0.0165 + 0.0007 0.0050 +0.0057 c ESqeucioln.d CDoensco.rptiinon mg/1 0.0605 +0.0021 0.0410 + 0.0130 + 0.0028 0.0100 + 0.0010 +0.0 o ETqhuiirld. DCeosnoer.ptiionn mg/1 0.0525 + 0.0134 0.0260 + 0.0080 + 0.0099 0.0080 +0.0 0.0035 + 0.0035 E AnowonntSoAidls,orbed (Taxbl/em u1,g/gColum F) 15.57 8.52 4.78 2.72 1.43 F AnoAwfntteronFiSrositl Desorption, ug/g 14.64 8.05 4.53 . 2.59 3 1.39 : G AmAofutnetr SoencoSonidl Desorption, ug/g 14.16 7.72 4.43 2.51 1.38 H AmAofutnetr. TonhiSrodil Desorption, ug/g 13.7 7.52 4.36 2.44 1.35 : 1 PeErcHen)t Desorbed id 2 2 9 10 5 (\ 006552 TABLE 111 COMPARISON OF ADSORPTION COEFFICIENTS FOR A SELECTED GROUP OF PESTICIDES (Hanaker and Thompson, 1972) Chemical Kp (mobile) Chlorarben 12.8 (FC-143 = = = = = =m mmm m= 17) 2,4-D 32 (FC-95 = = = = = = = = = = == =45) Prophan s1 Bromacil 7 Monuron 83 simazine 135 Propazine 152 Dichlobenil 164 Atrazine 2 Chloroprophan 25 Prometone "300 Anetryn 380 . Diuron 485 # . Prometryne 513 fF (FM3925 - = = = = = = = - - 3,500) Chloroxuron 4,986 (FM 3422 - = == = = = = - - 15,000] Paraquat 20,000 (immobile) DOT 243,000 006553 16.0+ =: - |" 14. 0+ |- jroo |110.0== 0 -- --A A _-- Ema-- ar 0c . #% = 0.950 fe x/mR2=e-o1.7n.+ 77 C 2a s.T0-0 BT -- = a 2 - x/m=7.4+7.9C 6.0+ = 0.886 7 - c 8 arcC Rf~xm=aa+a6c RB =0.968 3 2.0vZar~RLwm=24459 Ross Lo: CE Mexm=14+16C # =0.635 0.04 e mm m m h mmfemme | 0.000 0.120 0.240 0.060 0.180 - 0.300 Equilibrium Concentration in Water Phase, C, mg/1 FIGURE 1 : FM-3925 ADSORPTION AND DESORPTION ISOTHERMS 006554 = PLAT C41 C42 46.0ca%1 44.0 El az.or- 2- z %- . a0.0v 3 C- o. ~ .2 38.0%=* i So. xt/m==0.388.825 + 8.0C . 4 36.0 mmm mmm fmmhmmm mmm =A C42 : 0.00 Equili0b.r2i0um 0.40 Concentration in0S.o6lu0tion, 0.80 C, mg/l 1.00 FIGURE 2 FM-3925 DESORPTION FROM GLASS TUBE 5 Initial | First Desorption Second Desorption Thixd Desorption TABLE IV F-35925 DESORPTION FROM GLASS TUBE DATA : ESoqluuitliiobnr,iunC,Comngc/.l in 1.007 0.141 0.043 : 0.062 TAumboeu,ntx/Rm,e.maiyngi/Tnugbeon 46.1 0.5 8.8 Loa . 006555 Initial FM-3422 Conc., 2160 (100%) 1629110 ((5362%%)) 328196 ((1180%%) 21.6 (1%) APPENDIX 1 RAH FM-3925 SOIL ADSORPTION DATA = (ug/1) EAqGuiBl. arCeoncD.u,pliC,cagte/lSamples, yg/1 Duplicate.Injections into GC A 131766,,114707 10542,,15025 39A,38 5 -_250 15845,,81051 436@5,,4354 EAq'ugilB.arCeoncD.iplinicaFtierstSamDpelseosr,ption Duplicate Injections into GC A 15260,,15169 281,62,516 5,55 ES 2 1622,,15192 3516,,3157 9,9 Ed EAq'u&ilB.arCeoncD.iplinicaSteecoSnadmpDleesso,rption Duplicate Injections into GC wm 5492,,5490 10,911 5 < J 62-,62 . 15 << Ss EAq'uGilB. arCeoncD.uplinicTahtierSdamDpelseosr,ption Duplicate Injections into GC Control : :; Control A B A B 2660,,2663 44-,02 <s,8<,58 815.,185 6,6 << < Ed I1sntitial 18851,51,98172 23nrdd 8682,84 119460,,914200 55,,555 006556 Equil. Conc. ug/l A J 131787 251503 10s5z 683 39 3s APPENDIX TT AVERAGES OFFROMDUPALPIPCEANTDEIXINIJECTIONS we/1) First Desorption A Bn 12506 1o1t2 1267 3157 <s 9 Second Desorption et --B 5a9 110 1-s <5 s Third Desorption A fe 2&6 4:3 <s 5 155 6 s control A B Mean + 5.0." i InFiirtsitalDesorption STehciornddDeDseosroprtpitoinon 188484 5g/1 88s2 11570 ug/l b<y 1104017.5+%25615.8 44135v2595.74.3 006557