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BACK TO MAIN 3M Environmental Laboratory ReporNt o. W1878 Study Title Hydrolysis Reactions of Pertluorooctane Sulfonate (PFOS) Data Requirement: Based on OPPTS: 835.2110 Author Thomas L.Hafield, Ph.D. Study Completion Date March 27,2001 Performing Laboratory 3M Environmental Laboratory Building 2-3E-09,935 Bush Avenue St. Paul, MN 55106 Project Identification 3M Laboratory ReportNo: W1878 Total Number o fPages 71 Page 1 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 This pagehas been reserved for specific country requirements. Page 2 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Statement of Non-Compliance Study Title: Hydrolysis Reactions of Perfluorooctane Sulfonate (PFOS). Study Identification Number: W1878 This study does not comply with the requirements UofSthEePA Good Laboratory Practices Standards at 40 CFR Pa7rt92 (TSCA). However, many GLP standards were used in the developmentof the analytical method (Appendix A), and the quality assurance procedures followedin this study were based on the practices described in the GLP documentation. Spo'nsor Representative Date Page 3 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Quality Assurance Statement Study Title: Hydrolysis Reactions of Pemuorooctane Sulfonate (PFOS). Study Identification Number: W1878 The following table provides details of the audits performed b3yMthEenvironmental Laboratory Quality Assurance Un(Qit AU). Inspection Dates Phase Date Reported to Management Study Director I 8/11/00,8/16-17/00 I Daantad DraftReport I 8/18/00 II 8/18/00 I I I I 1 9/7,8,11/00 I I I 1 -1 3/13- 1 14/0 Daantad Draft Report RDerapfot rt 9/11/00 3/14/01 9/11/00 3/14/01 Page 4 of 71 BACK TO MAIN 3M Environmental Laboratory ReporNt o.W1878 Table of Contents Statement of Non-Compliance ............................................................................................ 3 Quality Assurance Stateme.n...t.......................................................................................... 4 List of Tables ........................................................................................................................ 6 List of Figures....................................................................................................................... 6 Study Personnel and Contribut.o..r..s.................................................................................. 6 Locationof Archives............................................................................................................. 7 Summary.............................................................................................................................. 8 Introduction .......................................................................................................................... 9 Summary of Kinetics Mode.l.............................................................................................. 10 Materials and Method..s..................................................................................................... 11 Chemical Characterization.s......................................................................................... 11 Sample Preparation...................................................................................................... 11 Sample Analysis............................................................................................................ 12 Deviations...................................................................................................................... 12 Results and Discussion..................................................................................................... 14 Data Quality Objectives (DQO.'.s..).............................................................................. 14 Anomalous Analytical Resu.l.t.s.................................................................................... 14 Statistical Methods and Calculatio.n..s......................................................................... 15 Data Summary and Discuss..io...n................................................................................ 15 Conclusions........................................................................................................................ 19 References......................................................................................................................... 20 Signatures .......................................................................................................................... 21 Appendix A: Analytical Method.......................................................................................... 22 Appendix B:Kinetics Mode.l.............................................................................................. 38 Appendix C: Selected Analytical and Kinetics Resu..l.t.s................................................. 48 Appendix D: Selected Chromatograms............................................................................. 59 Page 5 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 List of Tables Table 1. Summary of Results Based on PFOS Concentratio.n...s.................................... 8 Table 2. Summary of Results Based on the Mean and Precision of PFOS Measurements ...................................................................................................... 8 Table 3. Characterizations of Test and Reference Substanc...e..s................................. 1 1 Table 4. Observed (50' C) Slopes of PFOS Concentrations in Aqueous Buffered Solution for Various pH Leve..ls......................................................................... 15 Table 5. Calculated Slope of PFOS ConcentrationinsAqueous Buffered Solutions Using Data Pooled Over All pH Le.v..e...ls......................................................... 16 Table 6. Degradation Rate and Half Life ofPFOS in Aqueous Buffered Solutions Based on the Concentration Mean and Standard Deviati.o..n...................................... 18 List of Figures Figure 1. Structure of the Potassium Salt of PF...O....S.................................................... 9 Figure2. Observed PFOS Degradation for Various pH lev.e..l.s.................................... 16 Figure 3. Pooled PFOS Data and Slope Regressio.n...................................................... 17 Study Personnel and Contributors Study Director Thomas L. Hatfield, Ph.D. 3M Environmental Laboratory Building 2-3E-09 935 Bush Avenue St. Paul, MN 55106 (651) 778-7863 Sponsor 3M Corporation ProfessionalServices Contributing Personnel Kuruppu Dharmasiri, Ph.D. Kevin Macklin Mark T. McCann Anthony E. Scales Angela Schuler Joseph J. S. Tokos, Ph.D. (Pace Analytical Services, Inc., 1700 Elm St., Minneapolis, MN 55144) Page 6 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No.W1878 Location of Archives The 3M Environmental Laboratory will retain the original data documents and digital copies of the original data relattoetdhis work for at leas1t0 years following the effective date of any related final ruling. Information may obtained through written inquiry addressed as follows: 3M Environmental Laboratory Building 2-3E-09 935 Bush Avenue St. Paul, MN 55106 Page 7 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo.W1878 Summary We report here the results of our study of the hydrolysis of perfluorooctane sulfonate (hereafter, PFOS). Our methods are described below and in AppentdoixthAis work; our results are baseodn the observed concentrations of PFOinSbuffered aqueous solutions as a function of time3". s Environmental Laboratory staff developed the study procedures; they are based oEnPAs OPPTS Guideline Document 835.21I O ' but do not fulfill all the requirements of the guidelTinhee. chosen analytical technique was high petformance liquid chromatography with mass spectrometry dete(HctPioLnUMS). Table 1 summarizes the results of the study. During this study, we prepared and examined samples at six different pH levels between 1.5 and 11.Oover a period of 49 days, and our results indicate no dependence of the degradation rate of PFOoSn the sample pH level. We have excluded the "D0ay samples because they were improperly stored before analysis; see the "Deviations" section below. Our observations of the PFOS concentrations for dthaey i4n2cubation period (IDay 7"through "Day49), pooled over the six observed pH levels, are presented in Table 1. I Table I.Summary of ResultsBasedon PFOS Concentrations. I Calculated slope Calculated slope upper limit(20) Calculated slope lower limit (20) (day') (day-') (day-') 2.98 X 10" 5.30 x 10-4 6.66x IO-' These results indicate no degradation of PFOS; the derived positive slope does not provide a half-life estimate. The mean value and precision of PFOS concentrations do provide an estimate of the PFOS half-life, presented in Tab2le. I Table 2. Summary of Results Based on the Mean and Precisionof PFOS Measurements Half Life Page 8of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Introduction Three primary chemical routes of environmental degradation are hydrolysis, photolysis, and biodegradation. Studies of these routes provide information the environmental persistence of both the "parent" compounds and their reaction products, and are ideally carried out over the range of chemical conditions petrotinbeontht environmental and metabolic processes. The hydrolysis of the potassium salt of PFOS (or, more generally, its degradationin the presenceof H20)is addressed in this report. The structuoref the PFOS salt is illustratedin Figure 1. Fiaure I.Structure of the Potassium Saltof PFOS .. FFFFFFFFO Page 9 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Summary of Kinetics Model A full mathematical description of the kinetics model emplionytheids study is presented in Appendix B. The data in similar studies typically allowtwo independent estimates of the hydrolytic half-life, but only one estimisataevailable from our PFOS data. A first estimateis usually basedon the observed degradation of the compouinndilute, cp appropriately buffered aqueous solutions. Equation BIO describes the estimated half- lifeintermsoftheestimatedtotalhydrolysisrate : =- In(2) kP Eq. 1 We attemptedto determine the quantityG pfrom the experimental data as described in Appendix B. The data corresponding to "Day7" were usedto determine the relative concentration ratios (see the "Deviations" section below; see also Equations B8 and B9). The derived rates, both at various pH levels and when pooled over all pH levels, were poorly determined, and indicate only that PFOS does not degirnaadqeueous solution. A half-life second estimate (see Equation B37) is available from thepmaenadn standard deviation0of the observed PFOS concentrations, assuming that they were essentially constant over the experimental portiofnthe study. This estimate is Eq. 2 where A t represents the sample incubation period. All the samples useidn this study were maintained a reaction temperature of 50"(& 3") C. The quoted results, valid for the reaction temperat2u5r"eC, were calculated from our experimental results according to methods described in AppBendix (Eq. B38 and B39). Page 10 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No.W1878 Materials and Methods Details of the characteristics of the test materials, sample preparation techniques, and analytical methods are presenteidn Appendix A (ETS-8-13.0, "Hydrolysis of Perfluorooctane sulfonate (PFOS) and Analysis by High Performance Liquid Chromatography with Mass Spectrometry Detection"). A summary of these iteisms provided below, as well as a description the known deviations from the procedures of Appendix A. 3M prepared and analyzed the samples included in this study between May 24 and July 12,1999. Chemical Chamctemizations Table 3 describes the sources and properties of the materials iunstehdis work. These materials were usedto prepare both the samples and the quantitative standards toused quantify them. For this reason, and because Equation 1 involves only ratios of the parent and product concentrations, the resulting rate and half-life estimates are largely independent of the material purity levels. 1 Table 3. Characterizations of Test and Reference Substances PFOS (Potassium Salt) THPFOS Source Chemical Lot 1 Number Physical I I Description Molecular Weight (gm mole-`) Batch # 171 I ICN Biomedicals 3M ICPIPCP Division Batch # 53406 LighctolorepdowdeBrrowwnaxsyolid 538 428 Sample Preparation We prepared four .O1 -mL aqueous buffer samples (a sample, a duplicate, a triplicate, and a matrix spike at each of six pH levels (15.,57,3, ,9 and 11) for analysis at eight time intervals(0, 7, 14,21,28, 35,42 and 49 days). Buffered solutions containing 501.5 ng/mL of the potassium salt of PFOS and 368 ng/mL of THPF3O,4S,4(,3,5, 5, 6,6, 7, 7, 8,8, 8-tridecafluorooctane sulfonic acid), the latter serving as a surrogate for the compoundPFOS, formed the basis of all these samples. The chosen buffer solutions are described fully in Appendix A. All the samples were prepared simultaneously, and all but the0"Dsaymples were placed in an orbital incubator/shaker maintained at 50(+" 3") C. After the appropriate incubation times, subsets of the sample vials were removed from the incubator; they were then spiked (as required) with the PFOS solution, diluted 1O:l with methanol containing the internal standard THPFOS, and refrigerated-4a"tC. Similar treatment of the "Day0 samples is prescribed by the analytical method (see AppAe)n; dthixey are Page 11 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 to be agitated for a minimuomf three minutes, diluted and spiked as described immediately above, and then refrigerated rather than incubated. In this study, the "Day 0 samples were not refrigerated; see the "deviations" section below. Except during the relatively short periods of time required to prepare them, all the samples were shielded from light. Eight calibration standards containing PFOS (30180to2 ng/ml) served as the quantitative basis of the study. All these standards were prepared at the appropriate pH levels using the buffer solutions described in AppAe.ndix Sample Analysis The equipment we used for the HPLC/MS anawlyassisa Hewlett Packard mode1l100 equipped with a Dionex lonPac@ NG-1 HPLC column (aqueous ammonium acetate/methanol solvent gradient) and an ALS Model G1322A degassing module. An ALS Model G1315A column heater maintained the column temperatu4re0aCt,a quaternary pump supplied a column flow rate ofm0u.3min, and an ALS Model G1313A auto-sampler provided5 pL sample injections. The detector was a Hewlett Packard MSD mass spectrometer, operateidn negative-mode electrospray ionization mode; anions of PFOS and THPFOS were detected at the mass-to-charge (m/z) ra4t9io9s, 427, respectively. We processed the resulting data using the computer prograHmP ChernStation for LC (Rev.A.06.0). Further analytical details, including the gradient elution program, instrument and detector parameters, and performance specifications, are presented in Appendix A. Deviations After incubation and priotor analysis, all samples were stored at temperatu(-r4e"sC or -20" C) rather than at the prescribed temperatur4e"oCf prescribedin the Method. The pH meter calibration was performed with townolystandards (at pH= 7.0 and 10.0) rather than at the three Method-prescribed pH le(v4e.0ls, 7.0, and 10.0). Only three ions were monitored in the analysis, instead of the seven specified in the Method. Two samples (PFOS1-57 and PFOS- 113) were quenched with18mL of MeOH rather thanthe prescribed9 mL,and the concentration results were corrected to refthleicstfact. The buffer solutions prepared for uasse"Day 0" samples were stored at room temperature for seven days priotro spiking with PFOS tesatnalyk and processing. This led to evaporation of the solutions and artificially raised the 0""Dcaoyncentrations. Two additional setosf samples were prepared and analyzaesdorigmlly intended for generation of the "Da0y" and "Day7" data. The results of these additional analyses indicated no measurable PFOS degradation in the first seven days. On the basis of these additional results, we have excluded the "0D"adyata h m the data set usetdo estimate the PFOS degradation rates and half-life; the "D7"aydata are usedin the calculationof the concentration ratios of Equation BF8o. r these "Day0" and "Day7" re-runs, the ammoniumacetate solution wa5s mMrather thanthe 2 mM specified in the method, and Page 12 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 the sample injection wa1s0pL rather thanthe specified10 pL; the continuing calibration verification samplealso exceeded the allowed 15% for these re-runs samples. Page 13 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 Results and Discussion Data QualityObjedies (DQO's) We briefly describe the data quality objectives apipnlitehdis study below. Appendix A describes themin greater detail. With the exceptions of the anomalous results noted below, all the DQO's were met. Appendix C presents the results for each sample set, organized by pH level. Calibrations. The minimum acceptable coefficient of determinati(oPn) for linearfits to calibration datais 0.990. The acceptance criterion for individual calibration points is that their values fall witkhi2n5% of the linear fit value; data outside this ranrege excluded and the linear ifsit recalculated. No more thantwo points may be rejected from a calibration data set. Data for the high or low calibration standards may be rejected, though this results in a smaller effective calibration range. The average results of calibrations performed before and after the analytical procedures are used to calculate the analyte concentrations. Continuing Calibration Verification (CCV).Selected calibration samples are examined at the beginning of, during, and at the end of each analytical procedure. The results may not deviabtey more thank 15% of the known values. Matrix Spikes. The acceptable percent spike recovery range70is% to 130%; recoveries outside this rang%e place the analysis out of control, and require intervention by the Team Leader or designee. Analyte specificity is demonstrated by acceptable analyte spike recoveries. Identically Prepared Samples.Triplicate sample results with relative standard deviations (RSDs) greater than25% place the analysis out of control, and require intervention by the Team Leadoer rdesignee. Solvent Blanks. Concentration results for solvent blanks exceed neit5h%erof the highest calibration standard n2o5r% of the lowest calibration level. System Suitability. Suitability was demonstrated by either an abbreviated mass-tocharge (m/z) check-tunoer performance ofa full auto-tune routine. Anomalous Analytical Results With the following exceptions, our analytical results met or exceeded the data quality objectives of Appendix A. 0 Spike Recoveries. The triplicate samplesPFOS-157through 159 (pH = 7.0) failed to meet this DQO and were rejected. Page 14 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Statistical Methods and Calculations Using functions providedin Microsoft@ Excel@ software, we calculated means, standard deviations, and first-order rate constants (see AppenBd,ixEquation B8) for various subsets of the acquired data. Our linear regressions included the determination of constant terms, that is, the regression fits were not fotorcpeadss through the origin. As described in Appendix B (Equations B38 and B39), rates measu5re0dCawt ere extrapolatedto 25C by dividing by a factor of 10; this approximation is valid for reactions, such as these, with Arrhenius heats of activation near 18 Kcal/mole.* Data Summary and Discussion The LOQ is defined as the concentration of the lowest (accepted) stanindathrde calibration set for which the known concentration exc4e0e0d%s of the indicated solvent blank level (see AppendiAx). During this study, the LOQ for PFOS was 308 ng/mL. Results for the surrogate compound THPFOS were very consistent throughout the study. The percent relative standard deviations of the measured values, calculated for each pH level, ranged from 1%.2to 3.4%. Table 4 presents the resultosf the slope determinations (see Equation B8) at six pH levels and50C. ~~ ~ ~ ~ _ _ Table 4. Observed (50" C) Slopes of PFOS Concentrations in Aqueous I Buffered Solutionfor Various pH Levels. Observed Slope (day-") Percent (20) Rate Uncertainty (day-") +I 3.0 0.00025 111 0.00032 73 5.0 0.0001 1 618 7.0 0.00015 253 9.0 0.00057 89 11 0.00030 161 Figure 3 illustrates these values, which are all positive, and the fact that they are generally only poorly determined; their percent rela2tiv0e(95% confidence) uncertainties range from 73%to 618%. The data do not indicate degradation of PFOS at any of the six pH levels. In the absence of a clear trend relating the degradation rate to sampliet ispH, appropriateto "pool" the data over pH level and determine the concentration slope using the entire data set. Figure 3 illustrates the results of this pooled analysis accotording Equation 1, and Table5 summarizes the results of the analysiIst.also indicates no degradation of PFOS, and the positive slope does not provide a half-life estimate. Page 15 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Table 5. Calculated Slopeof PFOS Concentrationsin Aqueous Buffered Solutions Using Data Pooled Over All pH Levels. Calculated slope (day-') 2.98 x 104 Calculated slope upper limit (20) (day-') 5.30 x Calculated slope lower limit (20) (day'') 6.66 x O I * ' Figure 2. Observed PFOS Degradation for VariouspH levels. 0.04 0.03 - _ . - -pH_1.5 0.02 - pH 3.C n 0.01 - \ - B E 0.00 - -0.01 - -0.02 - -0.03 ! 0 , pH 5.0 - - - ,pH 7.C - . I - pH 9.C - 1 - 1 pH 11 I I I I 10 20 30 40 50 Time (days) Page 16 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Figure 3. Pooled PFOS Data and Slope Regression. 0.05 0 Dashed Lines: 20in(lisatmelnoridtpcsept) Line: Solid y = 2.983E-04~- 5.616E-03 = 1E.-40811 0 10 20 30 40 50 60 time (days) The mean and standard deviation of thPeFOS data do providea useful estimate of its half-life. Details of the related calculations are presenteind below (see AppendixB, EquationsB36 and 837). The maximum degradation rateis given in Equation 3: and the minimum half-life is given in Equa4tion Eq. 3 Eq. 4 We note thatin both Equations3 and 4, the mean PFOS concentration( p p )and standard deviation(op) can be either molaorr mass quantities. Table6 presents the results of the calculation. Page 17 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 I Table 6. Degradation Rate and Half Lifeof PFOS in Based on theConcentration Mean and Standard Deviation 1 Page 18 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Conclusions We have performed a study of the aqueous hydrolysis of perfluorooctane sulfonate (PFOS). Six different pH levels were includinedthe study, which were carried out5a0tCand extrapolated to 25C. Our results basedon direct observation of the PFOS concentration indicate no hydrolytic degradation at any individual pH, nor do the data pooled over all six pH levels. From the mean value and precision of PFOS concentrations, we estimate the hydrolytic half-lifeof PFOS to be greater than 41 years. Page 19 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 ~~ References 1. "Fate, Transport and Transformation Test Guidelines: 835.2I1O : Hydrolysis as a Functionof pH," U.S. EPA Office of Prevention, Pesticides and Toxic Substances, publication number 712-C-98-057, January 1998. 2. Experimental Physical Chemistry", F. Daniels, et al., McGraw Hill Book CO. (New York), p. 131, 1962. Page 20of 71 Signatures BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Page 21 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Appendix A:Analytical Method Method ETS-8-13.0, "Hydrolysis of Perfluorooctane Sulfona(tePFOS)and Analysis by High Performance Liquid Chromatography with Mass Spectrometry Detection." This Appendix presents the analytical method employinedthis study. Page 22 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 3M ENVIRONMENTLAALBORATORY METHOD HYDROLYSOISF ~RFLUOROOCTANESULFONATE(PFOS) AND ANALYSISBY HIGH PEFWORMANCE LIQUIDcHR0MATOGRAPHYWIT.H MASS SPECTROMETRY DETECTION NMumetbheord: ETS-8-13.0 Adoption Date: a q los Effective Date: Approved by: Laboratory Page 23 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 1.0 SCOPE AND APPLICATION 1.1 This method defines the steps for analysis of perfluorooctane sulfonate (PFOS) hydrolysis products by high performance liquid chromatography(HPLC) with mass spectrometry(MS) detection and quantitation.It is based on EPA OPPTS: 835.2110 (Reference 18.1). PFOS anion is detected and quantifiedby this method usingthe anion of 1,1,2,2-tetrahydro(trideca)fluorooctane sulfonic acid (THPFOSa)s the internal standard. Representative chemical structureasre shown in Attachment A. 1.2 Compatibleanalytes. Perfluorooctanesulfonate (PFOS) and 1, 1,2,2 tetrahydro(trideca)fluorooctane sulfonic acid (THPFOS). 1.3 Acceptable matrices for analysis. Aqueous solutions at various buffered pHs. 1.4 This method is defined as performance-based. Target analyte or surrogate matrix spike recoveries (100 f 30%)are usedfor each sample matritxo evaluate method performance. (Refer to Section 10for the quality control parametetros be analyzed bythis method. Refer to Section 14 for the quality assurance evaluatiocnriteria for this method,) 2.0 SUMMARY OF METHOD 2.1 Aliquots of PFOS stock solution are addedto vials that contain b e e r s at pH 1.5,3.0, 5.0, 7.0,9.0, and 11.0. The vials are then placedin an orbital incubatorhhaker set at 50 4 3 "C.Sets of vials are removed at designated intervals and dthaete and time recorded..The aqueous sample from the hydrolysis of PFOSis diluted 1to 10 with methanol (MeOH) containing internal standard. PFOS, incubatedin one of the several buffersis separated on a reverse phase Dionex IonPacN@G-1 HPLC column usingan ammonium acetateMeOH solvent gradient, with detection by electrospray ionizatimoanss spectrometryin the negative mode. 3.0 DEFINITIONS 3.1 Method blank. An analyte-free matrix to whichall reagents are added in the same volumes or proportions as used in the sampling processing. The methobdlank is carried through the complete sample preparatioannd analytical procedure. Because the reagent in a hydrolysis experiment is the aqueous bufferw, hich is the solvent, the classical definition of a method blankis limited in applicability. The methobdlank is used to document contamination resultinfgrom the entire preparatioannd analytical process. 3.2 Solvent blank. A sample of analyte-free medium (for example, 10:90 buffered water/MeOH) that is not taken through the sample preparation proceTshsi.s blank is used to evaluate instrument contamination. 3.3 Sample triplicates.Three samples taken from and representaotifvtehe same sample source and separately carrietdhrough all steps of the extraction andanalyticalprocedures in an identical manner. 3.4 Matrix spike (MS). Prepared by addinga known mass of target analyte to specified amount of a sample matrix.This assumes thatan independent estimate otfarget analyte concentrationis available. Matrixspikes are used to determine theeffect of the matrixon the method's recovery efficiency. ETS-8- 13 .O PFOS Hydrolysis and Analysisby HPLCiMS Page 2 of 15 Page 24 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 3.5 Internal standard(IS). A known amount of a compoundor element similar in analytical behavior to the compound or eIemenot f interest, added toal1 samples and standards, and carried through the entire measurement processI.S responses provide a reference for evaluating and controlling the precision bainads of the applied analytical process. 3.6 Calibration standard.A dilution of various amounts ofa stock, intermediateor purchased standardto achieve standard solutionsin a concentrationrange of interest. Hydrolytic half-lives resultingfiom these analyses are calculated basoend analytical ratios and not absolute numbers. Therefore, results dodnepoet nd on the purity of the standards used. 3.7 Continuing calibration verification (CCV).Standards analyzed duringan analytical run to verify the continued accuracyof the calibration curve.This solution mayor may not be prepared fiom a different sourceor lot numberthan the calibration curve standards. 3.8 Dilution. A step in the hydrolysis study procedurien which a solvent is added to thetest analytehuffer solution to prepareit for instrumental analysis.This step occurs after the vials are removed from incubationand beforethe samples are analyzed. If the solvent used is miscible withthe test analyte/bufTer solution, the diluting solvent is merely added and mixed. If the diluting solventis non-miscible, a liquid-liquid extractionis performed. IS(s) may be incorporated into the diluting solvent, if desired. 3.9 Limit of quantitation (LOQ). The lowest concentratiotnhat can be reliably measured within specified limits of accuracy (see Sectio1n4s.1 and 14.2)and precision (see Section 14.3) during routine laboratory operating conditionsT. he LOQ is generally 5 to 10times the minimum concentration witha 99%confidence limit that the concentration is greater than zero. However, it may be nominally chosen within these guidelinetso simplify data reporting. For many analytes,the LOQ is selected as the lowest non-zero standard in thecalibration curve thaits greater than 4 times the level of the solvent blanks. Sample LOQ are highly matrix-dependent. 3.10 Residuals. The percentage difference betweetnhat actual known concentration in a standard, versus the result obtainedfiom the back calculation usinthge calibration curve's linear regression formula.For the purposes otfhe study, the acceptance criteria for the residuals are k 25%. Residual = known conc. -calculated conc. x 100 known conc. 4.0 WARNINGS AND CAUTIONS 4.1Healthandsafetywarnings 4.1.1 Wear the proper lab attire for all parts of this procedure. Wear gloves and proper eyewearat all times. 4.1.2 Handle all solvents in a hood for allparts of the describedsample preparation procedure. Whenever possible and practical, dilute samples witsholvent in a hood. ETS-8- 13 .O PFOS HydroIyis and Analysis by HPL#MS Page 3 of 15 Page 25 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No.W1878 4.1.3 For potential hazards of each chemical used, refetro material safety data sheets, packing materials, and 3M Environmental Laboratories ChemicHaal zard Review. 4.2 Cautions 4.2.1 Rinse all glassware in which standards are preparedwith 1:l acetoneMeOH, then dry to reduce the possibiliotyf contamination. 4.2.2 Ensure thatthe HPLC mobile phases are preparedfresh prior to beginning a run sequence, and that thereis sufficient quantityto complete the run. Do not allow the pump torun dry. 4.2.3 Ensure that before startingthe run sequence there is ample hard disk space on the computer to save allrun data. 4.2.4 Ensure thatthere is enough nitrogen in the supplytankto complete sequence rUnS. 5.0 INTERFERENCE 5.1 Contaminants in solvents, reagents, glassware, and other sample processingor analysis hardware may cause interference.Use the routine analysiosf laboratory method blanks to demonstrate that thereis no such interference. 5.2 , Contamination from columns, HPLC tubing, and detector components macyause interference at low detection levels.The routine analysisof solvent blanks must be used to demonstrate that there is no such interference. 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.1 1 EQUIPMENT Analyticalbalancesensitive to 0.1 mg Shaker, incubator capable of maintaining temperatuatre50 k 3 OC Hewlett-Packard (HP)1100 HPLC System, or equivalent 6.3.1 Pump, quaternary, Model G13 11A, or equivalent 6.3.2 Solvent degasser, Model G1322A or equivalent 6.3.3 Autosampler, ALS Model G1313A, variable injection volume capable 6.3.4 Columnheater,ModelG1316A Dionex IonPac@NG-1 colum3n5, mm x 4.0mm, 10 pmpacking ,or equivalent Mass spectrometer. Hewlett-PackardLC/MSD, or equivalent, capableof operating in the seIected-ion-monitoring mode Clock, digital. Onlyone clock shouldbe used, to insure unambiguousdocumentationof the correct performanceof procedures. Centrifuge capableof maintaining 3000 rpm for 5 min pH meter. Corning Model308 pWTemperature Meterwith 3-in-1 gelfilled combination electrode (pWreference/temperature), or equivalent Refigerator, capable of maintaining4-t 2 OC Data system. A PC computer capableof controllingthe HPLC systemas well as - recording and processingsignals from the detector Data analysis software: Hewiett-Packard ChemStation', Version A. 6.03 or more recent. ETS-8-13.0 PFOS Hydrolysis and Analysis by HPLUMS Page 4 of 15 Page 26 of 71 BACK TO MAIN 3M Environmental Laboratory ReporNt o. W1878 7.0 SUPPLIES AND MATERIAIS 7.1 Vials, 40-mL VOA (I-CHEM or equivalent) 7.2 Crimp-cap autovials, 1.5-mL 7.3 Labels 7.4 Graduated pipets, glass, disposablel,-mL to10-mL 7.5 Pasteur pipets, glass, disposable 7.6 Hamilton Gastight@ syringes (precisifon1% of total volume), 10-pL to 1000-pL 7.7 Volumetric flasks, various sizes 7.8 Beakers, glass, various sizes 7.9 Automaticpipettor, capable of dispensing 10-50p0L0 8.0 REAGENTS AND STANDARDS 8.1 Methanol(MeOH): HPLC/SPEC/GCgradefromEMScience,oreq-uivalent 8.2 18.0 Mi2 water. Water with lower resistance must not be used. 8.3 Ammonium acetate (approximately2 mM). This is chromatographicsolvent A (see Section 12.3.1). Example: An acceptable buffer solutionis made by weighingout 0.15 grams of ammonium acetate (reagent grade) intaoweigh boat and then quantitatively transferring to a 1-L volumetricflask. Add 10mL of MeOH as a preservative, dilute to the mark with 18.0 MSZ water andmix thoroughly. 8.4 Calibration and Standard Stock Solutions All weights shouldbe recorded to the neares0t.0001 g 8.4.1 PFOS prepared in MeOH. (Example: A PFOS stock solution is prepared at a concentration of approximately 10,000 pg/mL by weighing 0.1000g ofPFOS in a 10mL volumetric flask and bringingto themark withMeOH. This solution is diluted in MeOH to make additional standardas needed.) 8.4.2 THPFOS prepared in MeOH. (Example: A THPFOS stock solution is prepared ata concentrationof approximately 10,000pg/mL by weighing 0.1000 g of THPFOS in a 10 mL. volumetric flask and bringing to the mark with MeOH. This solution is diluted inMeOH to make additional standardsas needed.) 8.5 Internal Standard (THPFOS)/Diluting Solvent 8.5.1 THPFOSprepared in MeOH.(Example: a THPFOS internal standard solution is prepared to a concentrationof approximately 400 ng/mL bydiluting 100 pL of a 10,000 pg/mL THPFOS stock standard (Section 8.4.2in)to 2.5 L of MeOH. This solution willbe usedfor the finalMeOH dilution of samples priorto analysis. 8.6 Buffers for calibrationof pH Meter. Purchased pH calibration standardosf pH 4.0, 7.0, and 10.0 (Mallinckrodtor equivalent). 8.7 Buffer solutions for hydrolysis studyP. repare buffer solutionof pH 5.0 using guidelines fiom Fate, Transport and Transformation Test Guidelines (Referen1c8e.1). Prepare buffer solutionsof pH = 1.5,3.0,7.0,9.0, and 11.0 usingguidelinesf?om CRC Handbook of Chemistry and Physics (Reference 18.2). Prepatrhee buffer solutions in l-L ETS-8-13.0 PFOS Hydrolysis andAnalysis by HPLC/MS Page 5 of 15 Page 27 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 quantities. Calibrate a portable pWtemperature meter using purchased pH calibration standards of pH 4.0,7.0, and 10.0, and measure the pHof all buffer solutions. Prepare buffer solutions of pH 1.5,3.0,5.0,7.0,9.0, and 11.0 at ambient room temperature. The concentrations are given below. Record finpaHl measurements of all buffers. Store buffers in sealed glass containers. 8.7.1 pH 1.5 a) 207 mL of 0.1 N HCl (reagent grade) b) 125 mL of 0.2 M KC1 (reagent grade) c) Adjust pH to 1.5 with additional1N HC1 d) Bring to a final volumeof 1 L with 18.0Ma water 8.7.2 pH 3.0 a) 10.2 g potassium biphthalate (reagent grade) dissolviendapprox. 600 mL 18.0 MQ water b) pH adjusted with1N HCl to3.0 c) Bring to a final volume of 1 L with 18.0MQ water 8.7.3 pH 5.0 a) Approximately 3.8777 gammonium acetate (reagent grade)added to 250 mL 18.0 MQ water b) Add 250 mL 0.052 M acetic acid (reagent grade) c) Add 18.0 MQ water to about900 mL d) Add to glacial acetic acid (abou0t.5 mL)to adjust topH 5.0 e) Bring to a final volumeof 1 L with 18.0 Mi2 water 8.7.4 pH 7.0 a) 500 mL 0.1 M KHzPO,buffer (reagent grade) b) 291 mL 0.1 N NaOH (reagent grade) c) Adjust pH to 7.0 with either 1N HCl or 1N NaOH d) Bring to a final volumeof 1 L with 18.0MQ water. 8.7.5 pH 9.0 a) 46 mL of 0.1 N HCl b) 125 mL of 0.1 M borax (NqBO,*H,O) (reagent grade) c) Adjust pHto 9.0 with either1 N HCI or 1N NaOH d) Bring to a final volumoef 1 L with 18.0 M a water. 8.7.6 p H 11.0 a) 500 mL 0.05 M NaIICO2(reagent grade) b) 227 mL, 0.1 N NaOH ETS-8-13.0 PFOS Hydrobsis and Analysisby HPLUMS Page 6 Of 15 Page 28 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 c) Add water to 950 mL d) Adjust pH to 11.0 with 1N NaOH e) Bring to a final volume of L1 with 18.0 MR water 8.8 Test AnalyteandSpikesolutions: 8.8.1 PFOS test analyte solution. [Example: An analyte solution of PFOS is prepared by adding 0.5 mL of 10,000 pg/mL PFOS standard (Section8.4.1) to st 10-mL volumetric flask and dilutingto the mark with MeOH.A 10-pL aliquot of this solution is then added to1 mL buffer (Section 12.1.5), resuItingin a final concentration of approximately 500 n g / d after MeOH dilution (Section 12.1.11)]. 8.8.2 Spiking solution. pxample: A spikingsolution is preparedby adding 0.1 mL of an approximately 10,000 ppm PFOS standard (Section 8.4t.o1)a 10-mL volumetric flask and dilutingto the mark with MeOH. Final concentrationafter addition of the spike (Section12.1.12) and MeOH dilution (Section 12.1.11) is approximately 100n g / d of PFOS]. 9.0 SAMPLHEANDLING 9.1 Record times of initial preparation and dilution on the fluorochemical degradation (hydrolysis) analysis sample preparation sheet (AttachmBe)n.t 9.2 Once the 9.0 mL of diluting solvent (Section8.5.1) has been added to the hydrolysis mixtures, the samples shouldbe analyzed within24 hours. Alternatively, the samples should be stored at4f 2 "Cbefore dilution with MeOH and until analcyasnisbe performed. 10.0 QUALITCYONTROL 10.1 Internal Standards. IS(s) are added in a constant concentration to all standards, samples, and matrix spikes. 10.2 Sample triplicates. Prepare and analyze all samples in triplicate to provide a measure of the precisionofanalysis. The analyst shall accept RSD values (25%. RSD values of 25% orgreater shouldbe noted. Appropriate steps must be takento correct the problem before analysis is allowed to proceed (e.g. sample re-runs, additional blanks, etc.). Consult withthe Team Leader or designee for direction anfidnal acceptance orrejection of the analytical run. 10.3 Matrix spikes. Prepare a post-hydrolysis matrix spikefor each of the pHs used in the study. Concentrationsof the spike should be approximately equtaola mid-range calibration standard. The matrix spike sample should be analyzed immediaftoelllyowing the sample triplicatesto which it corresponds. The analyst shall accept percenstpike recoveries of 100rt 30%. Spike recoveries outsideof this range should be noted. Appropriate steps musbte taken to correct the problem before analyisiasllowed to proceed (e.g. reruns, additional blanks or spikes, etc.). Befotrhee analysis is allowed to proceed, consult with the Team Leader or designee for direcatniodnfinal acceptance or rejection of the analytical run. ETS-8-13.0 PFOS Hydrolysis and Analysis by HPLUMS Page 7 of 15 Page 29 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 10.4 Solvent Blank. Solvent blanks shouldbe runbefore and after every calibration curve, CCV, and after no more than20 injections. Acceptablevalues for the blankare values below thelimit of quantitation (LOQ)of the instrument (Sectio3n.9). If analyte carry- .over is a problem, use back-to back solvent blanks. 11.0 CALIBRATION AND STANDARDIZATION 11.1 Standard preparation. Prepare at leastsix calibration standardsof PFOS in MeOH. Standards from approximately300 n g / d to 800 n g / d PFOS are recommended. This solution should also contain appropriate concentratioonfsthe internal standard. 11.2 Calibration standards. Analyze theset of calibration standardsat the beginning of the m,after every 20 injections, andat end ofthe run.Use the data reduction software program for linear regression calculations to relate the analyte peak arveaersruastiothe amount ratio from the internal standard. ExternaI standard calibration mauysebde if data review shows a problem with the internal standard analysis. Consuwlitththe Team Leader or designee for direction prior to performinthge external calibration methodology. 12.0 PROCEDURES 12.1Sampleandspikepreparation 12.1.1 Before spiking with any of the stock standards, transfer approxim1amteLlyof the solutionto an autovial and cap iUt.se this smaller volumefor spiking to minimize theeffects of evaporationfrom stock solutions. 12.1.2 Determine the numbeorf time pointsthat will be analyzed. Each time point will have atleast four vials for eacphH, multiplied by the number of pHs analyzed. One vialat each level will be labeleads "sample", "duplicate",triplicate", or "spike". 12.1.3 Obtain the appropriate numbeorf 40-mL VOA vials with capsand cardboard boxes. Prepare appropriate sample preparation worksheets acnrdeate labels and affix to the vials. The labels should includthee sample number, pH,time point and initials of the analyst. Record the poHf each buffersolution, 12.1.4 Remove thecap of the VOA vial and add 1mL ofthe appropriate buffer solution to all of the pre-labeledvials. Always replace the cap immediately after any addition to minimize evaporation. 12.1s To all of the vials, add10 pL of thePFOS test analytesolution (Section 8.8.1) with a 10-pL Gastight@ syringe. Record the tiomfeaddition for each vial. 12.1.6 For "Time Zero" samples only, proceed to section 12.1.11.For all other samples, continueon to section 12.1.7. 12.1.7 Make sure that the cap has been firmly tightened and platchee samples back in the cardboard case. 12.1.8 Place the case into a pre-warmed incubatodshaker for the appropriate time. Record the time, temperature, and raotef shaking. Thetemperatureis determined by the conditions of the experiment. Continue to manually monitor the incubator temperaturedaily during the entire incubation. Recortdhe temperature on the sample preparation sheet (AttachmBe).nt 12.1.9 Remove the casefrom the incubator atthe designated preset time. ETS-8- 13.O PFOS Hy&olysis and Analysisby HPLC/MS Page 8 of 15 Page 30 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 12.1.10 Remove the vials from the case and placien racks. Allow the vials to cool for approximately 15 minutes to room temperature. Alternatively, refrigeratethe vials at4 k 2 "Cif solutions areto be quenched at a later date. 12.1.11 Using a 10-mL graduated pipet, add 9mL MeOH containing approximately 400ng/mL THPFOS internal standard (Section8.4.2)to each vial. 12.1.12 Using a25-pL Gastight syringe, add 10pL of PFOS spiking solution (Section 8.8.2) to the "spike" vials. Invert each vial several times mtoix the contents. 12.1.13 Aliquot approximately 1mL of each sampleto the appropriately labeled autovial. Cap the vials and mark the bottoomf the meniscus. 12.1.14 Place the vials in the HPLC autosampler. 12.2 Instrument set up 12.2.1 Check that the appropriate HPLCcolumn is in the instrument for each analysis. 12.2.2 Check that the correct eluent solutionsare in bottles to be used and that enough is available to complete the sequencerun. 12.2.3 Place the samples in the autosampler tray and construacstequence table with appropriate calibration standards, calibration check standards saonlvdent blanks. 12.2.4 Verify that all samples and standards are positioned correctly. Enter sequence information: sample or standard ID, method name, one injectpioenr sample. 12.2.5 Save sequence as analysis date (e.g. on March 14,1999 save sequence as 031499s). Save datato a subdirectory labeledwith analysis date(e.g. 031499). 12.2.6 Set post-sequence cornmand macro to shut down system (Example: "STANDBY" on HP systems). 12.3 HPLC set up: 12.3.1 Analysis of PFOS Samples from pHs 1.5,3.0,5.0,7.0,9.0 and 11.0. Install the column: DionexIonPac@NG-l,4.0x 35 mm, 10 pm or equivalent. Solvent A: 2 m M Ammonium Acetate in 1% MeOH (Section8.3) Solvent B:MeOH Solvent Gradient: Time, minutes %A %B Flow Rate 0.0 60 40 0.3 mLJmin 1.o 60 40 0.3 mL/min 4.0 5 95 0.3 mL,/min 8.0 5 95 0.3 mIJmin Post time: 5.0 minutes; Column Temperature: 40" C 12.4 Recommended Mass Spectrometer set up; * 12.4.1 Analysis of PFOS at pHs 1.5,3.0,5.0,7.0,9.0 and 11.0, ETS-8- 13.0 PFOS Hydrolysisand Analysis by HPLCYMS Page 9 of 15 Page 31 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 - Drying Gas Temp 300 "C 3500 V Capillary Voltage `Example conditionsare applicable to Hewlett Packard HP1l00 equipment only. Time 1 SIM 1 Identity I Gain I Fragmentor I Dwell I . . .. 5.6 400 PFHS 13C,(M-H) qualitative ion 1.O 70 5.9 427 THPFOS (M-H), quantitation ion 1.O 70 6.2 499 PFOS quantitation ion (M-H) 1.o 70 I 6.2 500 PFOS .a.ualitative ion I .o 70 * "Quant" ion forTHPFOS;**"Qua&' ion forPFOS 1- pduorohexanesulfonaide 2- perfluorohexanesulfonate 3- perfluorooctanesulfonamide 210 210 210 210 I 12.5 Autosampler set up* Autosampler: Autosampler Program: ALS ModelG1313A None Injection volume: 5.0 pL *Example conditions are applicableto Hewlett Packard HP1100 equipment only. 12.6 Sample analysis 12.6.1 Enter the standard, samplaend QC information into the sequence table. Analyze calibration standards, up 2t0oinjections, and the calibration standards again. If more than20 injections areto be run,analyze a continuing calibration standard (CCV) after every20 and runthe calibration standardsagain at the end of the sequence. Run solvent blanks aftetrhe highest calibration standard, before and aftetrhe CCV,, and aftethr e set of samples to check for any malyte carryover. 12.6.2 Identify the electronic acquisition files with an appropriateprefix. D o not exceed five characters if the sequence contains more than 99 lines. 12.6.3 Place the standards, samples, andQC (matrix spikes and sampleblanks) into the autosampler tray accordintgo the order they arleisted in the sequence. 12.6.4 Save the sequence table witha name correspondingto today`s date. (e.gi.f today is December 1,1998,save the sequenceas 120198.) 12.6.5 Start the sequence. 13.0 DATAANALYSIS AND CALCULATIONS 13.1 Peak Evaluation: Peaks mustbe symmetricin shape and identified byextracting compound specificions. Peaks consideredfor calibration musthave peak heights greater than 5 (five) timesthe baseline noisefor that regionof the chromatogram. Peak integrationis from baseline to baselintehrough a peak using automatiocr manual integration. Compoundswith isomers presentas a shoulder or as a discrete second peak ETS-8-13.0 PFOS Hydrolysis anddnalysis by HPLC'MS Page 10 of 15 Page 32 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No.W1878 should be integrated with the parent compound unless otherwise noted. Quantitation data are calculated usingTHPFOS as the internal standard. However, external standard calibration may be acceptable. Consult with the Team Leader or designedeirefcotrion prior to performing the external calibration methodology. 13.2 Calculation of k Calculate thePFOS concentrations in each of the pH matriceussing the curves obtained from the calibrations and the internal standard. Assuming first-order kinetics a rate constan(tk)can be determined by plotting: concentrations determined at some elapsed timt aend at t = 0, respectively. The slope of the resulting lineis k. The iL value for this plot should b>e0.800. For rZ values less than 0.800, consult the Team Leader or designefeor direction. 13.3 Calculate the PFOS concentrations in each of the pH matrices verstuussing the curves obtained from the calibrations and the internal (or external) standard. 13.4 Matrix spikes. Calculate the percent recovery for eaocfhthe matrix spikes.Using the observed matrix spike recoveries, calculatthee average spike recovery. Calculatethe matrix spike percent recoveries usingthe following equation: YORecovery = (observed spiked sample resu-lotbserved sample resultx) actual amount spiked 13.5 Sample triplicates. Calculate the relative standard deviatio(RnSD) for the triplicate samples: RSD = StandarDd eviatioxn Mean Conc. 100% This parameter is also known as the coefficient of variation, a measuorfethe confidence of the mean. 14.0 METHODPERFORMANCE 14.1 Coefficient of Determination(3.An acceptable coefficient of determination (13,for linear curves is 0.990 or greater. The curves-should be examined closely for linea& and intercept, particularly for accuracy of quantitatiaotnthe low andhigh ends of the curve. The acceptance criteria for curve-fitting residuals (Sectio3n.10) is & 25%. Alternative methods of curve fitting(e.g. quadratic) may be necessaryin some cases. An acceptable correlation coefficient (r) foqrkdratic curves is 0.990 or greater. Recordin the rawdata the reasons for using quadratic equations. 14.2 Matrix spikes. Performance based warning and controllimits are recommended for measurements of percent spike recovery from matrix spike sampTlhees.analyst shall accept percent spike recovery valuoefs 100& 30%. Spike recoveriesoutside of this range place the analysis out of control. Appropriate steps bmeutsatken to correct the problem before analysisis allowed to proceed. Consult the Team Leader odresignee for direction. ETS-8-13.0 PFOS Hydrolysis and Analysis by HPLC/MS Page 11 of 15 Page 33 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 14.3 Sample Triplicates. Performance based warning and controlimits are recommended for measurements of relative percent differenocfereplicate samples. The analyssthall accept RSD values <25 %. RSD values of25% or greater placethe analysis outof control. Appropriate steps must be taketoncorrect the problem before analysiiss allowed to proceed. Before analysisis allowed to proceed, consulthe Team Leader or designee. 14.4 Continuing calibration verification.If the percent differencefor the amount of measured analyteis greater than 15% from the true value, relatiovtehe initial standard curve, stop the run. Only those samples analyzed befotrhee last acceptablecalibration check standard will be used. Reanalyze remaining samples wainthew calibration curve. 14.5 Limit of Quantitation. The limit of quantitation is equal to the lowest standardin the calibration curve that is greater than4 times the level of the solvent blanks. 14.6 Solvent blanks. Solvent blanks shouldshow no morethan a 5% carry overfrom a high standard or calibration check standardI.f so, two solvent blanks may be necessaryto rule out instrumental contamination. If peaks with greatthearn 25% the peak area of a low standard value are observedin sequential solvent blankst,he runshould be stopped. This indicates instrument contamination. The instrumensthall be maintained by thoroughly cleaning the electrospray source, and replacing or cleaning columns, tubing, etc. 15.0 POLLUTION PREVENTIONAND WASTE MANAGEMENT 15.1 Dispose of sample wasteby placing in highor low BTU containers as appropriate. Use broken glass containers to disposoef glass pipettes. 15.2 Collect HPLC solvent waste inthe satellite accumulation can. Emptyinto the flammable storage drum in the hazardous waste collection area tohne 2nd floor. 15.3 Use smaller bore columns when possible to minimize waste generation. 16.0 REcoRlDs 16.1 Print out hard copiesof all graphics and data analysis summafroiersarchiving 16.2 Sign and date all graphics and label with instrument ID. 163 Fill out the hydrolysis sample preparation worksheet completemlayk, ing sure to include all initials and dates. 16.4 Print chromatograms and internal standard reports for all analyses. 16.5 Print calibration tables and curve informatiaonnd store in the raw data file. 16.6 Store hydrolysis sample preparation worksheeintsthe raw data file. 16.7 Enter all standard preparation informatioinn the standards preparation logbook.Make a photocopy of the logbook pageand include the copy in the raw data file. 16.8 Archive electronic dattao appropriate media when necessary. 17.0 ATTACHMENTS 17.1 Attachment A. RepresentativeChemicalStructures 17.2 Attachment B. HydrolysisSampleLogsheet ETS-8-13.0 PFOS Hydroiysis and Analysis by HPLUMS Page 12 of 15 Page 34 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 18.0 BIBLIOGRAPHY 18.1 Fate, Transport and Transformation Test Guidelines Office of Prevention, Pesticides and Toxic Substances (OPPTS)835.2110 Hydrolysis as a Function of pHE, PA 712-C-98- 057, January 1998. 18.2 CRC Handbook of Chemistry and Physics, 1st Student Edition,``Buffer Solutions Operational Definitionsof pH," RobertC.Weast, Ph.D., 1988,p. D-87. 19.0 AFFECTED OCUMENTS None. 20.0 REVISIONS Revision for ReRviesaisoonnNumber ETS-8- 13.O PFOS Hydrolysis and Analysis by HPLUMS Page 13 of 15 Page 35 of 71 BACK TO MAIN m c z 0 0 \\ ;o . BA" CK T. O. MAIN BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Appendix B: Kinetics Model This Appendix includes a mathematical descriptoiofnthe kinetics model employeind the study.Appendix Page 38 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No.W1878 Kinetics Model BI. Reaction Componentsand Rates The arguments below are based on the following idealized set of reactions representing the hydrolysis of a parent compounPdand its hydrolysis productAs ,, which numberN. The actual hydrolysis reactions that occur under neutral, acidic, and basic conditions are subsumed in these equations, and are assumed to proceed with pseudo-first order rates k,, (for the parent) ankd,, (for the parent's hydrolysis products). I-' + H,O krm w n, A,+Y, (m=ltoN) A, + H20 kh w Y, ( m =1 toN) (B2) where the general symboYls,, and Ym2representall the other hydrolysis products. B2. Parent Compound Concentrations Equation B1 indicates that the pseudo-first order differential change in the parent concentration P is given by which is equivalent to the dp=-[z separable differential equation P n, k,,]dt Equation B4 may be directly integrated .to obtain the general solution (-x ] Ink]= n, k,, t + C my, With the initial conditionP(t = 0) = Po,the specific solution to Equation Bis4 P =Po exp [-& n, k,, t]=P, e-kpt using the additional definitioonf the total parent hydrolysis rate Page 39 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 N k, = kn,, . Equation B6 can be re-writtenin a form that allows a least-squares estimate of the total parent hydrolysis rate: k,t =-In (i) Using the initia(lt =0)measured value of the parent concentratioPnoand later values P measured at later timest ,one can calculate and plot the (linear) quantity [- In (P/Po)] versus time and obtain a least -squares estimate of the slope of the line. The resulting slopeis the least-squares c, estimate of the total parent hydrolysis rate. Equation B6 indicates that over a period of timTeI': (the parent hydrolysis half-life) the parent concentrationP is reduced through hydrolysis by a factortwoof , where A least squares estimate?vtof the parent hydrolysis half-liisfetherefore available from B3. Product Compound Concentrations The pseudo-first order differential changes in the product concentra4ti,on(ussing Equations B2 andB6)are dA, = ( n,kp,P - k,,A,)dt = ( nmkPmPeO-kp - k,,A,)dt (B11) and the (first order, non-separable) differential equation governing the product concentrations is %+ k,A, = n,k,,Po e-kpt. dt The "standard form" of Equation Bi1s2 Page 40 of 71 BACK TO MAIN 3M Environmental Laboratory ReporNt o.W1878 Ab +S (t) A, = Q(t) where the "functionS" (t) is actually a constant: and Q(t)=n,k,,Po e-kpt . The general solutionA, to Equation B12is contained in where and There aretwo cases of Equation818 to consider. In the circumstance thakt, = k, , which occurs only when the hydrolysis orafttehe mthproduct is identical to the total parent hydrolysis rate, the general solution to Equation B18 is (for k, = k,) A, ekp=t n,k,,Po t +C and, using the initial conditioAn,(t =0 )= A, ,the specific solution to Equation18 is (for k, = k, ) A, = (nmkPmPtO+ A,) e-kpt We note that whenk, = k, = 0 (that is, when both the parent and potential product are hydrolytically stable), EquationB7 requires (also) thatk,, =0 , so Equation B20 becomes Page 41 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Am= A, indicating, as required, that the productconcentration does not change with time. The circumstancek, = k p is highly improbable, and is neglectedin the remainder of this discussion. However, the reader should beianrmind that the expressions derived below do not hold when the parent hydrolysiskr,aatned the product hydrolysis ratek,approach each other. In the more probable case, for whickh,, # k, (i.e. that the hydrolysis rateof the mth product is different from the total parent hydrolysis rate), the general solution to Equation B18is and the specific solution to Equation B18 with the initial conAdimtio(nt= 0)= Am, is nrnkPmPO kF' -kArn 1e-k,t - nmkPmPO kP -kAm e-kp t Of greatest interest here is the case in which the product compounds are kbneown to hydrolytically stable, that is, whekn, =0 for all m. In this case, EquationB23 becomes (for hydrolytically stable products) + A, =AmO nmkPmPO kP (1- e-kpt) . B4. Relationships Betweenthe Parent and Compound Concentrations Equations B7 and B24 can be combined to obtain (for hydrolytically stable products) Page 42of 71 so that or BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 (for hydrolytically stable products) (for hydrolytically stable products) Ifthe changesin the product concentrations are all small compared to the original parent concentration, that is,if we may use the expression (valid for -1 5 X I 1 ) ln(l+X)=X- -1x2 + -1 x 3 -1- x 4 +..... 3 L 2 J 4 and Equation823 becomes (for hydrolytically stable products and Page 43 of 71 BACK TO MAIN 3M Environmental Laboratory ReporNt o.W1878 or (for hydrolytically stable products andZ A , -Amo m k,t E m=l B5. Parent Half-Life Estimates Basedon Limits of Quantification ofthe Products In every experimental determination okf , ,there is some set of valuesA r Q(the "limits of quantitation") below which the product concentratioAns, cannot be reliably measured. If during an experiment carried out over the perioofdtimeA t all the product concentrations A, remain below their limitosf quantitation, then the maximum possible value of the ratek, is obtained by assuming (for all the products) 1th)aAt ,, = 0 and 2) at time =t A t ,the product concentrations have increasteodthe valuesA, = A Z Q . With these assumptions, the experimental data indicate that the reactionk,riasteless than some maximum value(kp)- as follows: (for hydrolytically stable products at concentrations below the limoiftsquantitation) Under the same circumstances and assumptions, the experimental data indicate that the parent half-lifeTI': (see Equation B9)is greater than the value(TVi). as follows: mm (for hydrolytically stable products at concentrations below the limofitqsuantitation) TVP2 1 1- =-- h-42) (kP - At Po In(2) The reader should note that Equations B32 and B33 are valid only wh1e)ntheboth products are hydrolytically stable and 2) the concentratioanlsl thoef potential products are measured. Otherwise, the quantity(k,),, in Equation B32 may not actually represent the maximum possible value of the rate conkst,a,natnd the related resuinlt Equation B33 for (TVi). is also questionable. mm Page 44 of 79 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 B6. Parent Half-Life Estimates Based on Limitsof Quantification and Experimental Precisionof Product Concentrations In certain experiments, some hydrolysis products are present at quantifiable but essentially constant concentrations over the tim( Aet ) of the experiment. In this case, it is the experimental precision of the measured product concentrations, rather than the limits of quantitation, which contribute to the estimate of the maximum value of the parent hydrolysis ratek, . If the set of concentrations measured for tmhethproduct have the mean valuep, and standard deviationCY,, the data do not exclude the possibility that the product concentration increased from the initialG,v,a,l-upe, to the value 0, +p, at time t= A t . Taking this possibility to be the actual case for the measured products, the maximum value of the quant(iAty, -A,, ) is 20,. This reasoning suggests that the following estimate of the maximum parent hydrolysisis rate appropriate: (for hydrolytically stable productsat either 1) constant measured concentrations with standard deviationOm or 2) concentrations below the limits of quantitation) r -1 kp5 k P ) , = I 1 A r Q + c20,j. *0' Below LOQ Cons tan t v i ) Under these circumstances and assumptions, the experimental data indicate that the parent half-life T1'i is greater than the value(T . as follows: nun (for hydrolytically stable products at eithe1r ) constant measured concentrations with standard deviationOm or 2) concentrations below the limits of quantitation) r 7-1 The reader should note that Equations B34 and B35 are valid only wh1e)nthbeoth products are hydrolytically stable a2n)dthe concentrations ofall the potential products are measured. B6. Parent Half-Life Estimates Based on the Experimental Precision of Parent Concentrations In certain experiments, the hydrolytic parent remains at an essentially constant concentration over the tim(eA t ) of the experiment. In this caseit, is the experimental . precisionof the measured parent concentrations that determines the maximum value of the parent hydrolysis ratke , If the set of concentrations measured for the parent have the mean valuepLapnd standard deviationo p ,the data do not exclude the possibility Page 45 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 that the product concentration increased from the initial vpaPlu-ecrP to the value pp + op at timet = A t . This reasoning suggests that the following estimate of the maximum parent hydrolysis raties appropriate: (for essentially constant parent concentrations with mean vaplupeand standard deviationG p) v i ) Under these circumstances and assumptions, the experimental data indicate that the parent half-lifeT1'i is greater than the value(T . as follows: nun (for essentially constant parent concentrations with mean vaplupeand standard deviationGp) B8. Temperature Dependence of the Reaction Rate and Half-Life In order to increase the speed of the reactions of interest, we conducted this experimental study using samples maintained at the tempera5tu0reC= 323 K. Of greater interest are the corresponding results for the environmentally important temperature 25C = 298 K. When the Arrhenius activation energy for a reacistioAnH,, Equation 838 B1 provides the following relationship between the hydrolysis ra(ktlesand k2)for that reaction at two different absolute temperature(sTland T2): where R = 1.99 x Kcal mole-' K-' is the ideal gas constant. Using the valueB2 AH, = I 8 Kcallmole, the rate ratiokl/k2at the corresponding temperatureTs,=298 K and T, =323 K is Page 46 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 Equation B39 indicates that the hydrolysis reactions of interest proceed approximately ten times more slowly 2a5t C than at the chosen experimental temperatoufre50C. Accordingly, the rate reactions reported here for the temperature 25Cteanretimes lower than those measured at 50C, and the hydrolysis half-life estimates reported here for 25C samples are ten times longer than those calculated from the 50C experimental data. References to Appendix B: ' I. N Levine, "Physical Chemistry," McGraw-Hill (New York), pp. 498-501 (1978). '* F. Daniels, etai., "Experimental Physical Chemistry", McGraw Hill (New York), p.131 (1962). Page 47 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Appendix C: Selected Analytical and Kinetics Results This Appendix includes selected sample data and their related kinetics results. For brevity, some solvent blank and continuing calibration verification results that did meet the data quality objectives have been excluded from the following tables. Howeavller, data failing to meet the data quality objectives are included below. Page 48 of 71 BACK TO MAIN -r BACK TO MAIN z 0 ? E 2 a 1- BACK TO MAIN u A * vl 0 t BACK TO MAIN sE ss B m 58 g s r s N 6 E - s $ s 0 BACK TO MAIN ae r $ 5 z 0 NNNNNNNNNNNNNNNN dddddddddddddddd NNNNNNNP dddddddu BACK TO MAIN z 0 BACK TO MAIN z 0 BACK TO MAIN co b 2 4 0 BACK TO MAIN 03 b 03 5 z 0 ,, BACK TO MAIN 3M Environmental Laboratory Report No. W1878 Figure 3. Pooled PFOS Data and Slope Regression 0.05 n p" + 0.00 E 4 6----- - - - -9. I I e - - -O- -F I 0 - W 0 V 0 -/.o*----- 0 S! 8 _ _ _0_ _ _8 _ _30_ _ . _ . - . - . - --0- - . - - - - - . . - . - - - - . - - 0 Solid Line: Dashed Lines: y = 2.983E-04-~5.616503 20 (lsimloiptse and intercept) R2 = 1.481E-01 -0.05 I I I 1 1 0 10 20 30 40 50 60 time (days) SUMMARY OUTPUT Regression Sfatisfics Multiple R 0.384852267 R Square 0.148111267 Adjusted R Square 0,126267966 Standard Error 0.010265446 Observations 41 .ANOV.A.. Regression Residual Total df SS MS 0.00.0600.70018.704015614232598637680268 39 0.00410907.90600105379 40 0.004824334 Intercept X Valiable I tCoeSEftnfaiconirdenartsd Stat -0.00506.010632-5185.850871057.912417-7069.201172087.2090813-5066.906172097.3090813566958 2.60013..40095106420.30892607930816279 F P-value Signitiiance F Lower95% Upper 95% L m r 95.0p%p9e5r.0% 6.65838Ea5 0.0060.65052.809309807E53-305 6.665E.3-05E-04 Page 58 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Appendix D:Selected Chromatograms A representative setof chromatogramsfrom the present studyis included in this Appendix. Page 59 of 71 BACK TO MAIN Calib. Data Modified : Calcuiate Based on *%. 9/24/1999 10:08:51 AMY Rel. Reference Window : Abs. Reference Window : . . Rel. Non-ref. Window : Abs Non-ref ' Window : MultTplFer .. Dilution Sample Amount Uncalibrated Peaks Partial Calibration .' : Correct All Ret. Tiines: I 5 ; 00.0 % I 0.000 min 1.0000' 1.0000 0.00000 II not reported Yes, identified pe.aks are recalibrated No, only for identified peaks Cunie Type Origin Weight ' Linear Included * .Eq~d. Recalibration Settings: Average Response Averagecaallilbrations Average Retention Time: Floating Average New 75% Calibration Report Options : Printout of recalibrations within a sequence: Calibration Table after Recalibration Normal Report after Recalibration If the sequence is done with bracketing: Results of first cycle (endingprevious bracket) Signal 1: .MSD1 427, EIC=426.7:427.7 Signal 2,: MSDl 499, EIC=498.7:499.7 Signal 3: MSDl 399, EIC=398.7:399.7 RetTime Lvl Amount Area Amt/Area Re G r p Name , , lPPbl I --I I - - - - - - - - _ -1 - - - - - - - - - - 1 - - - 1 - - 1 - ~ , - - - - - - - - - - - - - 1 300.90000 3.78048e4 7.95930e-3 . , PFWS 11 300.90000 3.80593e4 7.90609e-3 2'. 401.20000 4.74013e4 8.46390e-3 22 401.20000 5.14873@4 7.79221e-3 3 451.35000 5.60681e4 a.05003e-3 33 451.35000 5.86619e4 7.69409e-3 4 501.50000 6.94725e4 7.21869e-3 44 501.50000 6.86155e4 7.30884e-3 5 541.62000 6.91006e4 7.83813e-3 . 55 541.62000 6.74844e4 8.02586e-3 6 601.80000 7.89434e4 7.62318e-3 66 601.80000 7.90989e4 7.60820e-3 7 .702.I O O O O 8.70628e4 8.06430e-3 77 702.10000 9.13195e4 7.68839e-3 8 802.40000 1.00442e5 7.98866e-3 Page 60 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Method C:\HPCHEM\l\METHODS\O922-5O.M RetTime Lvl A m o u n t Area - - -[-m- - -i1n- -l1 - -S1 -i-g- - - - - - - - ~ - - - - -[- -P-P- -b- -l- - - - - - - Amt /Area 5.931 88 1 1 2 3 ~ 802.40000 1.00128e5 8.01373e-3 367.92000 4.73070e5 7.77729e-4 367.92000 4.60726eS -7.98565e-4 3-~67.92000 4.39572e5 8.36996e-4 4 367.92000. 4.90981e5 7.49357e-4 5 367.92000 4.67449e5 7.87080e-4 .- . . ..- 6 367.92000 4.57579e5 8.04058e-4 7 .367.92000 4.3.5372e5 8.45071e-4 8 367.92000 4.52504e5 8.13075e-4 11 367.92000 4.61022e5 7.98052e-4 22 367.92000 4.61213e5 7.97722e-4 33 367.92000 4.53927e5 8.10526e-4 44 367.92000 4.55268e5 8.08140e-4 55 367.92000 4.57342e5 8.04475e-4 6.6-367,92000 4.52098e5 ,8.'13806e-4 77 367.92000 4.56825eS 8.05384e-4 .88 367.92000'4.52021e5 8..13945e-4 6.2222 1 300.900090.20859e35.26760e-4 PFOS. . I 21 300.90000 9.24706e5 3.25401e-4 2 401.20000'1.21379e6 3.30534e-4 22 401.20000 1.22485e6 3.27551e-4 3..451.35000 1.32239e6 3.41314e-4 33 451.35000 1.34445e6 3.35713e-4 4 501.50000 1.56794e6 3.19846e-4 44 501.50000 1.51715e6 3.30554e-4 5 541.62000 1.636.0le6 3.31062e-4 55 541.62000 1.63668e6 3.30926e-4 6 601.80000 1.76299e6, 3.41353e-4 66 601.80000 1.79159e6 3.35902e-4 7 702.10000 2.03577e6 3.44881e-4 77 102.10000 2.07740e6 3.37970e-4 8 802.40000.2.31841e6 3.46099e-4 =---- 802.40000 2.34731e6 3.41839e-4 8 8 ----P=s==PIOIE=P=10=I==I=3rP=rPI91=P=P=P=~==~===x~================== Peak Sum Table ---- ' 'OI=P=~=Pe====rpt=ll- --- -- - -- -0- =1= 3=r==~=== Page 61 of 71 BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Method C:\HPCHEM\1\METHODS\O922_50.M THPFOS at exp. RT: 5.931 MSDl 427, EIC=426.7:427.7 Correlation: -0.99395 Residual Std. Dev.: 12673.93865 Formula: y = mx + b ' '.. m: 1244.66095 . b: -3.54902e-10 x: Amount [ppbl y : Area PFOS at exp. RT: 6.222 MSDl 499, EIC=498.7:499.7 0.99860 Correlation: Residual Std. Dev.: 31589.73759 Formula: y = mx + b m: 2878.88299 b: 51022.56267 x: Amount Cppbl y: Area. Page 62 of 71 Batch Run# 1 of 60 Data File D:\DATA\O92399\PFOSOOOl.D BACK TO MAIN 3M Environmental Laboratory ReporNt o. W1878 Sample Name: MeOH Blank By Sorted Signal Calib. Data Modified : 9/24/1999 10:08:51 AM Multiplier ,1.0000 . Dilution 1.0000 Signal 1: MSDl 427, EIC=426.`7:427.7 Totals : 0.00000 Totals : 0.00000 Page 63 of 71 Batch Run # 1 o f 60 Data File D:\DATA\O92399\PFOSOOOl.D BACK TO MAIN 3M Environmental Laboratory ReporNt o. W1878 Sample Name: MeOH Blank I Totals : 0.00000 1 Warnings or Errors : warning : Calibrated compound(s1 not found' Sorted By Calib. Data Modified : . . --Multiplier Dilution Signal ' 9/24/1999 10:08:51 AM 1.0000 *' i;oooo Signal 1: MSDl 427, EIC=426.7:427.7 Name Totals : 0.00000 Totals : ' 0.00000 Signal 3: MSDI 399, EIC=398,7:399.7 Peak RetTime Type WiAdrteha Area Name - -#-.- I - -[;m-i-n-l- ~ - - - - - - J -[m- -in-l- - - J - - - - - - - - - - l - - -%- - -. - - l - - - - - - - - - - - - - - - - - - - - - 1 5.642 0.0000 0.00000 0.0000 PFHS Totals : ' 0.00000 Page 64 of 71 Batch Run # 1 qf 60 Data F i l e D:\DATA\O92399\PFOSOOOl.D 1 Warnings o r Errors : BACK TO MAIN Sample Name: MeOH Blank -+ Page 65 of 71 Batch Run . # 6 of 60 Data F i l e D:\DATA\O92399\PFOSOOO6.D BACK TO MAIN 3M Environmental Laboratory Report No. W1878 I Sample Name: L4 Std, 501.50 Sorted By Calib.DataModified : Multiplier Dilution Signal 9/24/1999 10:08:51 AM 1.0000 1.0000 Signal 1: MSDl 427, EIC=426.7:427.7 Page 66 of 71 Batch Run# 6 of 60 Data F i l e D:\DATA\O92399\PFOSOOO6.D BACK TO MAIN 3M Environmental LaboratoryReport No. W1878 Sample Name: L4 S t d , 501.50 Page 67 of 71 Batch Run# 18 of 60 Data F i l e D:\DATA\092399\PPOSOOli.D BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Sample Name: PFOS-035 Sorted By . . Calib. Data Modifi,ed : Multiplier . Dilution Signal I: MSDl 427, 61C0426 Page 68 of 71 Batch Run # 18 of 60 Data File D:\DATA\O92399\PFOSOO18.D BACK TO MAIN 3M Environmental Laboratory ReporNt o. W1878 Sample Name: PFOS-035 Page 69 of 71 BACK TO MAIN 3M Environmental Laboratory ReportNo. W1878 Batch Run# 19 of 60 ' Data File D:\DATA\O92399\PFOSOOl9.D Sample Name:PFOS-036 '===13=IPI==1====t='DPP--- ---=s------------,=---------- _---- _ _ - -----=-----=---=--- ---==r==n=====xs 'InjectionDate : 9/23/1999 2 : 0 8 : 5 8 PM Seq. Line : 19 NSaammeple 1 : PFOS-036 Vial : 18 Acq. Operator: : MTM 'tnj : .I *,. '' InVjolume : 5 ,d Acq. Method i : C:\HPd\l\METHODS\PFO5-NG2.M Last changed j : 9/23/1999 9:SO:OO AM by MTM Analysis Methbd : C:\HPCHEM\l\METHOD5\0922_50.M Last changed : 9/24/1999 10:12:55 AM by MTM (Results are froampreviously saved Batch) SIM Analysis'jES-) for THPFOS, PFOS, and PFHS using4mmx35mm Dionex NG1 column, SlN12879. IonPac .MTM _C------ Signal 2 : MSDl 499, EIC=498.7:499.7 RetTime Type Area A/mAtrAemaount G r p ,Name - - -[- -m- -iI n- -l- - - - I - - - - - - - - - - l - - - - - - - - - - l - - - - - - - - - - l - - ~ - - - - - - - - - - - - - - - - - - [PPbl ' 6.231 BB 1.898623e.638022e6-41.77689 PFOS Totals : 641.77689 Page 70 of 71 BACK TO MAIN 3M Environmental Laboratory Report No. W1878 Batch Run # 1 9 of 60 Data F i l e D:\DATA\o9,2399\PFOSOOl9.D S i g n a l3 : RetTime hinl MSDl 399, EIC=398.7:399.7 Type Area Amt/Area Totals. : 680.89256 Sample Name: PFOS-036 c Page 71 of71