1、Designation: D7968 17aStandard Test Method forDetermination of Polyfluorinated Compounds in Soil byLiquid Chromatography Tandem Mass Spectrometry (LC/MS/MS)1This standard is issued under the fixed designation D7968; the number immediately following the designation indicates the year oforiginal adopt
2、ion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This procedure covers the determination of selectedpolyfluorinated compou
3、nds (PFCs) in a soil matrix usingsolvent extraction, filtration, followed by liquid chromatogra-phy (LC) and detection with tandem mass spectrometry (MS/MS). These analytes are qualitatively and quantitatively deter-mined by this method. This method adheres to multiplereaction monitoring (MRM) mass
4、spectrometry. This proce-dure utilizes a quick extraction and is not intended to generatean exhaustive accounting of the content of PFCs in difficult soilmatrices. An exhaustive extraction procedure for polyfluo-ralkyl substances, such as published by Washington et al.,2fordifficult matrices should
5、be considered when analyzing PFCs.1.2 UnitsThe values stated in SI units are to be regardedas standard. No other units of measurement are included in thisstandard.1.3 The Method of Detection Limit3and Reporting Range4for the target analytes are listed in Table 1.1.3.1 The reporting limit in this tes
6、t method is the minimumvalue below which data are documented as non-detects. Ana-lyte detections between the method detection limit and thereporting limit are estimated concentrations and are not re-ported following this test method. In most cases, the reportinglimit is calculated from the concentra
7、tion of the Level 1calibration standard as shown in Table 2 for the polyfluorinatedcompounds after taking into account a 2-g sample weight anda final extract volume of 10 mL, 50 % water/50 % MeOH with0.1 % acetic acid. The final extract volume is assumed to be10 mL because 10 mL of 50 % water/50 % M
8、eOH with 0.1 %acetic acid was added to each soil sample and only the liquidlayer after extraction is filtered, leaving the solid and anyresidual solvent behind. It is raised above the Level 1 calibra-tion concentration for PFOS, PFHxA, FHEA, and FOEA; thesecompounds can be identified at the Level 1
9、concentration butthe standard deviation among replicates at this lower spikelevel resulted in a higher reporting limit.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-pri
10、ate safety, health and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopm
11、ent of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:5D1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Metho
12、ds of Committee D19 on WaterD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisE2554 Practice for Estimating and Monitoring the Uncer-tainty of Test Results of a Test Method Using ControlChart Techniques1This test method is under the jurisdiction of
13、ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.01.06 onAnalytical Methods.Current edition approved Sept. 1, 2017. Published September 2017. Originallyapproved in 2014. Last previous edition approved in 2017 as D7968 17. DOI:10.1520/D7968-17A.2Washington, J
14、. W., Naile, J. E., Jenkins, T. M., and Lynch, D. G., “Character-izing Fluorotelomer and Polyfluoroalkyl Substances in New and AgedFluorotelomer-Based Polymers for Degradation Studies with GC/MS and LC/MS/MS,” Environmental Science and Technology, Vol 48, 2014, pp. 57625769.3The MDL is determined fo
15、llowing the Code of Federal Regulations, 40 CFRPart 136, Appendix B utilizing solvent extraction of soil. Two-gram sample ofOttawa sand was utilized. A detailed process determining the MDL is explained inthe reference and is beyond the scope of this standard to be explained here.4Reporting range con
16、centration is calculated from Table 2 concentrationsassuming a 30-L injection of the Level 1 calibration standard for the PFCs, and thehighest level calibration standard with a 10-mL final extract volume of a 2-g soilsample. Volume variations will change the reporting limit and ranges.5For reference
17、d ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.This international standard was developed in accordance with internationall
18、y recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.12.2 Other Documents:6EPA SW-846 Test Methods for Evaluati
19、ng Solid Waste,Physical/Chemical Methods40 CFR Part 136 Appendix B Definition and Procedure forthe Determination of the Method Detection Limit3. Terminology3.1 Definitions:3.1.1 reporting limit, RL, nthe minimum concentrationbelow which data are documented as non-detects.3.1.2 polyfluorinated compou
20、nds, PFCs, nin this testmethod, eleven perfluoroalkyl carboxylic acids, threeperfluoroalkylsulfonates, Decafluoro-4-(pentafluoroethyl)cyclohexanesulfonate, and six fluorotelomeracids listed in Table 1 collectively (not including mass labeledsurrogates).3.2 Abbreviations:3.2.1 CCCContinuing Calibrati
21、on Check3.2.2 ICInitial Calibration3.2.3 pptparts per trillion, ng/kg or ng/L3.2.4 LCLiquid Chromatography3.2.5 LCS/LCSDLaboratory Control Sample/LaboratoryControl Sample Duplicate3.2.6 MDLMethod Detection Limit3.2.7 MeOHMethanol3.2.8 mMmillimolar,110-3moles/L3.2.9 MRMMultiple Reaction Monitoring3.2
22、.10 MS/MSDMatrix Spike/Matrix Spike Duplicate3.2.11 NANot available3.2.12 NDnon-detect3.2.13 P however, this test method isintended to be performance based and alternative operatingconditions can be used to perform this method provided dataquality objectives are attained.4.2 For PFC analysis, sample
23、s are shipped to the lab on iceand analyzed within 28 d of collection. A sample (2 g) istransferred to a polypropylene tube, spiked with surrogates (allsamples) and target PFC compounds (laboratory control andmatrix spike samples). The analytes are tumbled for an hourwith 10 mL of methanol:water (50
24、:50) under basic condition(pH 9-10 adjusted with 20 L ammonium hydroxide). Thesamples are centrifuged and the extract, leaving the solidbehind, is filtered through a polypropylene filter unit. Aceticacid (50 L) is added to all the filtered samples to adjust thepH 3-4 and then analyzed by LC/MS/MS.4.
25、3 Most of the PFC target compounds are identified bycomparing the single reaction monitoring (SRM) transition andits confirmatory SRM transition if correlated to the knownstandard SRM (Table 3) and quantitated utilizing an externalcalibration. The surrogates and some PFC target analytes(PFPeA, PFBA,
26、 FOUEA, and FHUEA) only utilize one SRMtransition due to a less sensitive or non-existent secondarySRM transition. As an additional quality control measure,isotopically labeled PFC surrogates (listed in 12.4) recoveriesare monitored. There is no correction to the data based uponsurrogate recoveries.
27、 The final report issued for each samplelists the concentration of PFCs, if detected, or RL, if notquantifiable, in ng/kg (dry weight basis) and the surrogaterecoveries.5. Significance and Use5.1 This test method has been developed by the U.S. EPARegion 5 Chicago Regional Laboratory (CRL).5.2 PFCs a
28、re widely used in various industrial and commer-cial products; they are persistent, bio-accumulative, and ubiq-uitous in the environment. PFCs have been reported to exhibitdevelopmental toxicity, hepatotoxicity, immunotoxicity, andhormone disturbance.Adraft Toxicological Profile for Perfluo-roalkyls
29、 from the U.S. Department of Health and HumanServices is available.7PFCs have been detected in soils,sludges, and surface and drinking waters. Hence, there is aneed for a quick, easy, and robust method to determine thesecompounds at trace levels in various soil matrices for under-standing of the sou
30、rces and pathways of exposure.5.3 This method has been used to determine selected poly-fluorinated compounds in sand (Table 4) and four ASTMreference soils (Table 5).6. Interferences6.1 All glassware is washed in hot water with detergent andrinsed in hot water followed by distilled water. The glassw
31、areis then dried and heated in an oven at 250 C for 15 to 30 min.All glassware is subsequently rinsed with methanol or acetoni-trile.6.2 All reagents and solvents should be pesticide residuepurity or higher to minimize interference problems. The use ofPFC-containing caps should be avoided.6.3 Matrix
32、 interferences may be caused by contaminants inthe sample. The extent of matrix interferences can varyconsiderably depending on variations in the sample matrices.6.4 Contaminants have been found in reagents, glassware,tubing, glass disposable pipettes, filters, degassers, and otherapparatus that rel
33、ease polyfluorinated compounds. All of thesematerials and supplies are routinely demonstrated to be freefrom interferences by analyzing laboratory reagent blanksunder the same conditions as the samples. If found, measuresshould be taken to remove the contamination or data should bequalified; backgro
34、und subtraction of blank contamination is notallowed.6.5 The liquid chromatography system used should consist,as much as practical, of sample solution or eluent contactingcomponents free of PFC target analytes of interest.6.6 Polyethylene LC vial caps or any other target analyte-free vial caps shoul
35、d be used.6.7 Polyethylene disposable pipettes or target analyte-freepipettes should be used. All disposable pipettes should bechecked for release of target analytes of interest.6.8 Degassers are important to continuous LC operation andmost commonly are made of fluorinated polymers. To enableuse, an
36、 isolator column should be placed after the degasser andprior to the sample injection valve to separate the PFCs in thesample from the PFCs in the LC system.7A draft Toxicological Profile for Perfluroalkyls can be found at http:/www.atsdr.cdc.gov/toxprofiles/tp.asp?id=1117 this shouldinclude a sampl
37、e injection system, a solvent pumping systemcapable of mixing solvents, a sample compartment capable ofmaintaining required temperature, and a temperature-controlled column compartment. An LC system that is capableof performing at the flows, pressures, controlled temperatures,sample volumes, and req
38、uirements of the standard shall beused.7.1.2 Analytical Column9A reverse phase Charged Sur-face Hybrid Phenyl-Hexyl particle column was used to developthis test method.Any column that achieves adequate resolutionmay be used. The retention times and order of elution maychange depending on the column
39、used and need to be moni-tored.7.1.3 Isolator Column10A reverse phase C18 column wasused in this test method to separate the target analytes in the LCsystem and solvents from the target analytes in the analyticalsample. This column was placed between the solvent mixingchamber and the injector sample
40、 loop.7.2 Tandem Mass Spectrometer System11A MS/MS sys-tem capable of multiple reaction monitoring (MRM) analysisor any system that is capable of meeting the requirements inthis test method shall be used.8A Waters Acquity UPLC H-Class System, or equivalent, has been foundsuitable for use.9A Waters A
41、cquity UPLC CSH Phenyl-Hexyl, 2.1 100 mm and 1.7-m particlesize column, or equivalent, has been found suitable for use. It was used to developthis test method and generate the precision and bias data presented in Section 16.10A Waters Acquity UPLC BEH C18, 2.1 50 mm and 1.7-m particle sizecolumn, or
42、 equivalent, has been found suitable for use.11A Waters Xevo TQ-S triple quadrupole mass spectrometer, or equivalent, hasbeen found suitable for use.TABLE 3 Retention Times, SRM Ions, and Analyte-Specific Mass Spectrometer ParametersChemicalPrimary/ConfirmatoryRetention Times(min)Cone (V) Collision
43、(eV) MRM TransitionPrimary/Confirmatory SRMArea RatioPFTreAPrimary10.6320 13 712.9668.97.4Confirmatory 20 30 712.9169PFTriAPrimary10.1725 12 662.9618.97.4Confirmatory 25 28 662.9169PFDoAPrimary9.6110 12 612.9568.98.2Confirmatory 10 25 612.9169PFUnAPrimary9.0515 10 562.95197.2Confirmatory 15 18 562.9
44、269PFDAPrimary8.4520 10 512.9468.96.5Confirmatory 20 16 512.9219PFOSPrimary8.7810 42 498.980.11.3Confirmatory 10 40 498.999.1PFNAPrimary7.7820 10 462.9418.94.9Confirmatory 20 16 462.9219PFecHSPrimary8.110 25 460.93812.2Confirmatory 10 25 460.999.1PFOAPrimary7.1120 10 412.93693.6Confirmatory 20 16 41
45、2.9169PFHxSPrimary7.3915 32 398.980.11Confirmatory 15 32 398.999.1PFHpAPrimary6.3515 10 362.93194.1Confirmatory 15 15 362.9169PFHxAPrimary5.5415 8 312.926924.1Confirmatory 15 18 312.9119.1PFBSPrimary5.6610 30 298.980.11.6Confirmatory 10 25 298.999.1PFPeA Primary 4.68 10 8 263219 NAPFBA Primary 3.67
46、10 8 212.9169 NAFHEAPrimary6.1415 20 376.92933.6Confirmatory 15 6 376.9313FOEAPrimary7.5415 18 476.93934.3Confirmatory 15 12 476.9413FDEAPrimary8.8315 8 576.84933.2Confirmatory 15 15 576.8513FOUEA Primary 7.54 20 12 456.9392.9 NAFHpPAPrimary7.5415 12 440.93371.1Confirmatory 15 20 440.9317FHUEA Prima
47、ry 6.08 10 12 357293 NAMPFBA Primary 3.67 10 7 217172.1 NAMPFHxA Primary 5.54 15 8 315270 NAMPFHxS Primary 7.39 15 34 402.984.1 NAMPFOA Primary 7.11 15 10 417372 NAMPFNA Primary 7.81 15 9 467.9423 NAMPFOS Primary 8.78 15 40 502.980.1 NAMPFDA Primary 8.45 15 10 514.9470 NAMPFUnA Primary 9.05 15 10 56
48、4.9519.9 NAMPFDoA Primary 9.61 15 12 614.9569.9 NAD7968 17a47.3 CentrifugeA device to centrifuge the samples.7.4 Lab Rotator12A device to mix the samples by end-over-end rotation.7.5 Filtration Device:7.5.1 Hypodermic SyringeA luer-lock tip glass syringecapable of holding a syringe driven filter uni
49、t.7.5.2 A 10-mL lock tip glass syringe size is recommendedsince a 10-mL sample size is used in this test method.12A Lab Rotator, or equivalent, has been found suitable to mix samples.TABLE 4 Single-Laboratory Recovery Data in Ottawa SandSampleMeasured ng/kg from Ottawa Sand P some sources of PFC standards thathave been found suitable for use were fromAldrich Chemical Company, WellingtonLaboratories, Inc., and Wako Laboratory. Standards from other vendors may beused.16PFC surrogates from Wellington La
