Document 6vGpo0QqY7e99YoNGEGyYyLd

SOIL ADSORPTION TEST SUBSTANCE Identity:N-ethylperfluorooctasnuelfonamidoethanolm;ay also be referredtoas N-ETFOSE Alcoholor FM-3422. (1-Octanesulfonamide,N-ethyl1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-N-(2-hydroxyethyly, CAS # 1691-99-2) Remarks: Materialisan off-whitew,axy solidof uncharacterizedpurity. METHOD Method: Adsorption-desorptiosntudiesdeveloped usingprocedures describedby Davidson, 1976 and Hamaker, 1975. GLP (Y/N): No Year (study performed): 1978 Statisticalmethods: Statisticalnalysisand plottingof the data was done withthe MIN ITAB package ofthe3M TRAC computer service. Temperature: 16-19*C duringthe 24-hoursofwdst-actionshaker exposure. Stock and testsolutionpreparation: The stocksolutionwas made by putting a few milligramsN-ETFOSE alcoholinD.I.water and stirrinwgitha magnetic stirrefrorseveraldays.The supernatantwas poured intoa graduated cylinderto settlefor4 days and then 50 ml portionswere drawn offand centrifuged.The testsolutionswere made by dilutinagliquotsofthe stocksolution. Remarks field: The Bdlisandy loam soilwas characterizedas having 57% sand, 36% silt7,% clay,2.5% organicmatter,1.5% organiccarbon,withpH 6.5 and cationexchange capacityof 15.3meq./l00 g. Standard solutionswere prepared indeionizedwater atconcentrationsof0.49 mg/L, 0.27 mg/L, and 0.16 mg/L. Forty-fivemi ofeach solutionwas shaken with5 gram samples ofthe soil in50 ml glasscentrifugetubes for24 hours induplicateon a wristshaker at room temperature(16-190C). Desorptionextractionwsere performed withdeionizedwater afterthe adsorption phase ofthe experiment.The samples from the adsorptionand desorption experiments were centrifugedindividualalty3000 rpm for10 minutes,and 40 mi of each supernatantsolutionwere extractedwithethylacetateforanalysisby . GC. The remainingsupernatantwas drainedoffand 45 mi of D.I.water were put intothe tubes. RESULTS K: 392* K.,r: 26,147* Remarks field: The lineasrhapeoftheadsorptioinsotherimndicatetdhatNETFOSE alcoholadsorptionon soilwould be independent ofconcentrationin solution. * The study reporthad indicateda K of 330. This isthe coefficienotfC inthe regressionequation,not theadsorptioncoefficienvtalue. A K.. valuewas calculatedusingtheformula:K,.c= 100 K/% organiccarbon. However, the calculatiounsed an organiccarbon contentof2.2% whilethe reportindicatesthe organiccarbon tobe 1.5%. This isa discrepancy.Ifthe 1.5% value isused along withthe correctedK value,the K. becomes 26,147. CONCLUSIONS The study substance isexpectedtoexhibitlow mobilityinthe kindof soiltested. Submifter: 3M Company, EnvironmentalLaboratory,P.O. Box 33331, St.Paul, Minnesota,55133 ..DATA QUALITY Reliability:Klimischranking3. The purityofthe testsubstance isunknown. Testingwas not performedinduplicate.There was no analysisofthe soilto verifyamount remaining.Additionallcyo,mments made by ProfessorStephen Boyd, MichiganStateUniversitayre summarized below and includedwiththe report.They alsoindicatethe unreliablneatureofthisstudy. The batch method does notcompensate forlossesdue to volatilizatisoonr,ption tothe container,degradation,or othermechanisms. The concentrationsused inthe studywere significantalbyove the solubilitlyimit ofthe testsubstance,indicatintgherewas crystallinNe-ETFOSE alcoholinthe stocksolution. The number ofdata pointsand range oftestsubstance concentrationsare too smallto definitivedleytermine soilsorption. Test parameters were not sufficienttoestablishthe isothermlinearity. REFERENCES 3M TechnicalReport "Adsorptionof FM-3422 on Soil."Stephen K. Welsh, Project9970612631, Fate of Fluorochemicals,Report No. 009, September 1, 1978. Review ofTechnicalReport Summary. Adsoprtionof FM 3422 on Soil. ProfessorStephen A. Boyd, Michigan StateUniversityM,ay 19,1993. OTHER Lastchanged: 5/17/00 Attachedarecomments on the 3M TechnicalReport "AdsorptionofFM-3422 on Soil.Stephen K. Welsh@ Project9970612631 Fate ofFluorochemicalsR,eport No. 9,Sept.1,1978" made by ProfessorStephenA. Boyd, Mchigan StateUniversityd,atedMay 19,1993. Review of TechnicalReport Summary Adsorptionof FM-3422 on Soil This reportdescribesa batchsorption/desorptioinsothermexperiment forFM 3422 on a single sandy loam soil.FM 3422 has a reportedsolubilitiyn water of 0.05 mg/L (50 ppb). This is considerablylower thanFC-95 or FC-143. FM 3422 isa non-ioniccompound whereas FC 95 and FC 143 areboth anionic.Itwould be very helpfulto have accuratewater solubilitiaensd octanol-wateprartitiocnoefficientfsor thesecompounds. The lattewrould be more usefulin predictingK. valuesusingempiricalrelationshipbsetween K. and K,,.thathave been reported intheliteratureW.ater solubilitioefssolidsare more difficultto use forpredictingK. because theyshouldbe convertedfirsto thecorrespondingsupercooledliquidsolubilitiesA. favorable comparisonof measured K. to K. predictedfrom K.,,usingpublishedempiricalrelationships would strengthenmy confidencein thesevalues. One problem with thebatch method used is thatany loss(e.g.,by volatilizatiosno,rptionto the container,degradation)iscounted as soil sorptionwhich resultsin higherapparentK values. Materialand Methods The concentrationosf FM 3422 preparedin distillewdater are given as .49 mg/L, 0.27 mg/L and 0.16 mg/L. However in the abstracthe water solubilitiys reportedas 0.05 mg/L. We have a discrepancyhere of a factorof 10? Eitherthe 0.05 mg/L solubilitiys wrong or there was crystallinFeM 3422 inthe stocksolution.The number of datapoints(three)and therange of concentrationasre both too small. The range of concentrationsevaluatedshould be at least an orderof magnitude,withatleastfiveor sixinitiacloncentrations.Also, theisothermshould be extendedto a soluteconcentrationthatapproaches itswater solubilityt;hisis the only way to establisthhelinearitoyf the isotherm. Resultsand Discussion The threeconcentrationtsested,and the narrow r-angeof concentrationsisn'tsufficientto establishisothermlinearity. The conclusionthatbindingof FM 3422 to soilinvolveselectrostatfiocrcesis notjustified.In fact,thedatado not indicateelectrostatiincteractionsT.h'is mechaiiism would almost certainly give non-linearisotherms.High sorptioncoefficientcsan be obtainedwithout involdngsome mechanism based on strong(e.g.,electrostatimco)lecularinteraction.My opinionisthat.FM 3422 partitionisntosoilorganicmatterin the same sense thatitwould partitionintoa bulk organic.solvenpthase such as octanol.The magnitude of the sorptioncoefficienitsa ratioof thesolubilitiynthe soilorganicmatterphase to thesolubilitiyn water,analogousto an octanolwater partitiocnoefficientT.he magnitude of the sorptioncoefficienitsdetermined largelyby the water solubilitoyf the solute.The water solubilitoyf FM 3422 is apparentlyquitelow, hence the sorptioncoefficienitshigh. DDT isa good example of a compound with low water solubilit(y5.5ppb) resultinigna highsorptioncoefficientC.ertainlyDDT does not sorb by an electrostatimcechanism. The partitionmechanism does manifestlinearisotherms. As faras an electrostatiincteractiotnh,iswould requireprotonatioonf thenitrogen.Itwould be usefulto know thepKa of thecompound; thenthelikelihooodf electrostatiincteractionwsith soilorganicmatteror soilclayscouldbe evaluated. Again the K. calculatiounses-anorganiccarbon contentof 2.2%. The value given in the materialasnd methods is 1.5%, so thereis a discrepancyhere. Ile K,,,calculatioins appropriatfeornonioniccompounds thatpartitioinntosoilorganicmatter.For compounds that sorb by electrostatiincteractiontsh,e Y..,v.alueisnot applicable.In thatcase the degreeof sorptionwould probablybe relatedmore directlyto thecationexchange capacityof thesoil. The K. valuedoesappeartobe quitehigh,and ifcorrectw,ould indicatleow mobility. Recommendations 1. Get an accuratewatersolubilit(yS,,a,n)d K.. valuesforFM 3422. 2. Measure thepKa ofFM 3422 ifthisisnotknown. 3. Measure additionasloilsorptionisothermsusinga wider rangeof solute(FM 3422) concentrationwshich shouldapproachthewatersolubilitoyfthecompound. That is,in your isothermthereshouldbe a datapointwhere C S,,or 0.5 S,@,. 3%m~' 1:,," r374 7 11 A TECHNICAL REPORT SUMMARY @at9 /l/78 TO: TECHNICAL COMMUNICATIONS CENTER - 201-2CN r)portan-tIfreportisprintedon bothsidesofpapers,endtwocopiestoTCC.) Division . Environmental Engineering & Pollution Proiect Fate F:F*--poTrittle of Fluorochemicals Adsorption of FM-3422 on Soil To A. N. Welter Atithor(s) Notebook Stephen K. Welsh Reference #40673 SECURITY POP, 0 open (Company Confidential) C' Closed (i@@cial Authorization) Control 3M CHEMICAL :@R@EICGISTRY P' Dept. Nurnbet 0535 7,oioct-Nmbe' 9970612631 We-p-o-rt-Wmu-bor 009 Employee Number(s) 73583 No. of Pages Inct, ding Covershoot 8 New ChemicalRseported 0 Yes E] No KEYWORDS. (Seletcetrmfsrom3M Thesaurus.Suggestother applicable terms.) CURRENT OBJECTIVE: To obtain an indication of FM-3422 mobility in a sandy loam soil. EE & PC Div. Fluorochemical Soil -'.dsorption r4obility REPORT ABSTRACT: (200-250 words) This abstractinformation isdistributedbv the Technical Communications alert3M'ers to CoffVany R&D. It isCompany confidentialmaterial. Center to To obtain an indication of mobility of FM-3422 in a sandy loam soil, adsorption/desorption experiments similar to those of Davidson, 1976 and of liamaker, 1975 were conducted. FM-3422 was judged to be immobile based on an adsorption coefficient of 330; less than 5% desorption with two desorption extr actions; and water solubility of only 0.05 mg/l. Inn.formation Liaison tials: 2 CONCLUSIONS The adsorption coefficient for FM 3422 was 330. Considering the adsorption coefficient, desorption characteristics, and water solubility, FM 3422 would be judged immobile in the sandy loam soil used in this study. INTRODUCTION As a part of the Fate of Fluorochemicals Project, an indication of mobility of FM 3422 in sandy loam soil was desired. Adsorptiondesorption experiments (after Davidson, 1976 and Hamaker, 1975) along with water solubility data can provide this indication of mobility. This approach is used by the U.S.E.P.A. in pesticide registration requirements. MATERIALS AND METHODS Duplicate 5-g samples of air-dried Brill sandy loam soil (57% and, 36% salt, 7% clay, 2.5% organic matter, 1.5% organic carbon, with pH 6.5 and C.E.C. of 15.3 meg/100g) were shaken with 4S ml of solution in 50 ml glass centrifuge tubes for 24 hours on a wrist action shaker at room temp. (16-190 C). Glass tubes were used because they were found in separate experiments to adsorb less FM-3422 than polypropylene or polyethylene tubes. Solutions were made by diluting a stock solution of the chemical.@". The stock solution was made by putting a few milligrams FM 3422 in D.T. water on 1/25/78 and stirring with.magnetic stirrer for several days. On 2/6/78 the supernatant was poured into a graduated cylinder to settle until 2/10/78 when 50 ml portions were drawn off and centrifuged in glass tubes at 3000 rpm for 10 min. The centrifuged solution was put in a glass jar for storage. Concentrations of FM 3422 were 0.27 mg/l., and 0.16 mg/l (100%, 56%, 32% of stock). After shaking the initial solutions as well as the two desorption extractions with deionized waier, the samples were centrifuged at 3000 rpm for 10 min. and 40 ml of each supernatant solution were extracted with ethyl accetate (See APPENDIX I for procedure) for analysis by GC. After removing the 40 ml for extraction, the remaining supernatant liquid was drained off and 45 ml of D.I. water were put into the tubes. Statistical analysis and plotting of the data was done with the MINITAB package of the 3M TRAC computer service. RESULTS AND DISCUSSION Adsorption data for FM 3422 are given in TABLE I. The amount@of FM 3422 removed from solution by the soil (Column C) was 98% at all three starting (initial)concentrations. Equilibrium concentrations in solution(C) in mi/l. are shown in Column B and amounts adsorbed on the soil(x/m) in pg FM 3422 per gram soil are shown in Column F. The regression equation of the adsorption isotherm shown in FIGURE 1 was x/m 0.33 + 330C, so that the adsorption coefficient, K, was 330. The linear shape of the adsorption isotherm indicated that FM 3422 adsorption on soil would be independent of concentration in solution. The high percentage adsorbed and the relatively high adsorption coefficient indicated that FM 3422 would be immobile in this sandy loam soil. 4 A Initial FM-3422 Conc., mg/l. 0.49 (100%) 0.27 (56%) 0.16 (32%) D Total FM-3422 In Initial Solln, mg (A x 0.045 liters) 0.022 0.012 0.007 TABLE I FM-3422 Adsorption Data B Equil. Conc., C, mg/l. 0.0120 + 0.002 0.0063 + 0.005 0.0032 + O.OOOS E Total FM-3422 In Solln at Equil., mg (B x 0.045 liters) 0.00054 0.00028 0.00014 c % Removed by Soil A-B 100 Ax 98 98 98 F FM-3422 Adsorbed on Soil, xim ,gr/9 (D-E 10 /S 4.30 2.37 1.41 4.0 A ob 3.2 x 0 2.4 0 0 1.6 -A x/m 0.33 + 330 C+ R.-Squared 0.999 0.8 0.003 0.006 0.009 0.012 0.015 Equilibrium Concentration, C, mg/i FIGURE I I:M3422 Adsorption and Desorption Isotherms Solid line is idsorption isotherm, broken lines are desorption isotherms. A's are data for highest initial concentration, B's for middle initial concentration, C's for lowest initial concentration. Standard deviation for the "Allvalue furthest right is shown to indicate that this value may be acceptable. 5 Desorption data are given in TABLE II and the desorption isotherms are shown in FIGURE 1. Of the amounts initially adsorbed on the soil, less than 5% was removed by the two desorption extractions with water (TABLE II, Column G). This sn-all arount of desorption is also shown by the alriost horizontal slopes of the desorption isotherms. This very small amount of desorption was another indication of the immobility of FM 3422. TABLE II FM 3422 DESORPTION ISOTHERM DATA A Eq'uil. Conc. in Solution, C, mg/l. 0.0120 0.0063 0.0032 + 0.002 + 0.005 -Z o.ooos B Equil. Conc. in First Desorption Mg/l. 0.014 + 0.004 0.004 + 0.001 0.002 7 0 c Equil. Conc. in Second Desorption mg/l 0.002 + 0 0.002 + 0 0.002 7 o D Amount Adsorbed on Soil, X/M pg/g 4.302 2.373 1.411 E Amount on Soil After First Desorption, pg/g 4.176 2.337 1.393 F Amount on Soil After Second Desorption, pg/g 4.158 2.319 1.375 G' Percent Desorbed (D-F) 100 D 3.3 2.3 2.6 The large amount adsorbed and the small amount desorbed suggests strong binding of FM 3422 to soil particles by intermolecular interactions involving electrostatic forces. The adsorption coefficient based on soil organic carbon, Koc' for FM 3422 would be 15,000 (100 K/% organic carbon = lOOx330/2.2). Compared with Koc values for a selected*group of pesticides and other fluorochemicals (Table III ), 15,000 is quite high and is another indication of low mobility of FM 3422. TABLE III (mobile) (immobile) Comparison of Adsorption Coefficients for a Selected Group of Pesticides (Hamaker and Thompson, 1972) Chemical K oc Chloramben 12.8 (FC-143 - - - - - - - - - 17) 2,4-D 32 (FC-95 - - - - - - - - - 45) Propham 51 Bromacil 71 Monuron 83 Simazine 135 Propazine 152 Dichlobenil 164 Atrazine 172 Chloropropham 245 Prometone 300 Ametryn 380 Diuron 485 P-rometryne 513 Chloroxuron 4,986 (FM-3422 15,000) Paraquat 20,000 DDT 243,000 These adsorption and desorption data along with the low water solubility of FM 3422 (0.05 mg/l.) provide good evidence that I'M-3422 would have very low mobility in the sandy loam soil used in this study. Terms c - Concentration of chemical in solution at equilibrium x/m - Concentration of-chemical adsorbed on soil at equilibrium 2_ R Coefficient of determination K - Adsorption coefficient K - Adsorption coefficient based on soil organic carbon content oc References Davidson, J. M., et. al., 1975, Use of Soil Parameters for Describing Pesticide Movement Through Soils, U. S. EPA, EPA-660/2-75-009. Davidson, J. M., 1976, "Vertical Movement and Distribution of Organics in Soils," Presented at Symposium 2n Nonbiological Transport and Transformation of Pollutants on Land and Water, at National Bureau of Standards, Gaithersburg, MD., May 11-13, 1976. Hamaker, J. W., 1975, "Interpretation of Soil Leaching Experiements," in Chemicals, Human Health and the Environment, A Collection of Dow Scientific Papers, Vol. 1, Dow Chemical USA, Midland, Mich. 48640 Hamaker, J. W. and J. M. Thompson, 1972. "Adsorption" in Organic Chemicals in the Soil Environment. C. A. I. Goring and J. W. Hamaker (eds.-). Rarcel Dekker, Inc., N. Y. APPENDIX I FM-3422 Analytical Procedure Reference: N.B. #46269-50 - Results obtained from this method. The 40 ml H 2 0 samples that were submitted by S. K. Welsh on 2/2/78 were analyzed in the following manner. The 40 ml H 2 0 sample was placed in a 125 ml sep. funnel, fitted with teflon stopcock. 10 ml of saturated NaCi H 0 was added by pipet. 7 ml of ethyl acetate* added by pipet 2 to sample in sep. funnel. The funnel was inverted 50 times and the phase allowed to separate. The top EtAc phase was drawn off,with a transfer pipet and placed in a dry 10 ml volumetric flask. Note: Of the 7 ml EtAc added, 3 ml is recovered due to 10% EtAc solubility in H 2 0. Also, if emulsion is a problem the foamy layer of EtAc water can be placed in a glass contrifuge tube and spun at 5000 rpm for 10 min. to break emulsion. The EtAc is then transferred to the volumetric flask. The extraction is carried out a second and third time, as above, using 3 ml EtAc each time. All EtAc extracts combined in 10 ml volumetric flask which is then diluted to the line with EtAc. 5 'microliter injections of the samples were made with the following conditions. Standard FM-3422 EtAc are injected for comparison. into E.C.G.C. solutions in Inst: Hewlett-Packard Model 5713 equipped with Ni 63 electron capture detector. Column: 6' x 1/8" O.D. S.S. 10% CW-20M on 60/80 Mesh Chromosorb W-AW Oven Temp - 180 OC Is8thermal Inj. Port Temp - 200 C Det. Temp. - 3000C Flow 40 C.C./min - Argon: Methane 95:5 *Analytical Reagent - Mallinckrodt (R) - Ethyl Acetate G. A. Vraspir