1、Designation: D7600 16 (Reapproved 2017)Standard Test Method forDetermination of Aldicarb, Carbofuran, Oxamyl andMethomyl by Liquid Chromatography/Tandem MassSpectrometry1This standard is issued under the fixed designation D7600; the number immediately following the designation indicates the year ofo
2、riginal adoption 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 aldicarb,carbofur
3、an, oxamyl and methomyl (referred to collectively ascarbamates in this test method) in surface water by directinjection using liquid chromatography (LC) and detected withtandem mass spectrometry (MS/MS). These analytes are quali-tatively and quantitatively determined by this test method. Thistest me
4、thod adheres to multiple reaction monitoring (MRM)mass spectrometry.1.2 This test method has been developed by U.S. EPARegion 5 Chicago Regional Laboratory (CRL).1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 The Detect
5、ion Verification Level (DVL) and ReportingRange for the carbamates are listed in Table 1.1.4.1 The DVL is required to be at a concentration at least3 times below the Reporting Limit (RL) and have a signal/noise ratio greater than 3:1. Fig. 1 displays the signal/noiseratios of the primary single reac
6、tion monitoring (SRM) transi-tions and Fig. 2 displays the confirmatory SRM transitions atthe DVLs for the carbamates.1.4.2 The reporting limit is the concentration of the Level 1calibration standard as shown in Table 2 for the carbamates.1.5 This standard does not purport to address all of thesafet
7、y concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internatio
8、nally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1129 Term
9、inology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3856 Guide for Management Systems in LaboratoriesEngaged in Analysis of WaterD3694 Practices for Preparation of Sample Containers a
10、ndfor Preservation of Organic ConstituentsD5847 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 Techniques2.2 Other Documents:3EPA publicat
11、ion SW-846 Test Methods for Evaluating SolidWaste, Physical/Chemical Methods3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard, refer toTerminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 carbamates, nin this test method, aldicarb,carbofuran, ox
12、amyl and methomyl collectively.3.2.2 detection verification level, DVL, na concentrationthat has a signal/noise ratio greater than 3:1 and is at least 3times below the reporting limit (RL).3.2.3 independent reference material, IRM, na material ofknown purity and concentration obtained either from th
13、e1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved June 15, 2017. Published July 2017. Originallyapproved in 2009. Last previous edition appr
14、oved in 2016 as D7600 16. DOI:10.1520/D7600-16R17.2For referenced 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.3Available
15、from National Technical Information Service (NTIS), U.S. Depart-ment of Commerce, 5285 Port Royal Road, Springfield, VA, 22161 or at http:/www.epa.gov/epawaste/hazard/testmethods/index.htm.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United Stat
16、esThis international standard was developed in accordance with internationally 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 Tra
17、de (TBT) Committee.1National Institute of Standards andTechnology (NIST) or otherreputable supplier. The IRM shall be obtained from a differentlot of material than is used for calibration3.3 Acronyms:3.3.1 CCC, nContinuing Calibration Check3.3.2 IC, nInitial Calibration3.3.3 LC, nLiquid Chromatograp
18、hy3.3.4 LCS/LCSD, nLaboratory Control Sample/Laboratory Control Sample Duplicate3.3.5 MDL, nMethod Detection Limit3.3.6 MeOH, nMethanol3.3.7 mM, nmillimolar,1103moles/L3.3.8 MRM, nMultiple Reaction Monitoring3.3.9 MS/MSD, nMatrix Spike/Matrix Spike Duplicate3.3.10 NA, adjNot Available3.3.11 ND, nnon
19、-detect3.3.12 P Samplecompartment, 15C.6AWaters (a trademark of the Waters Corporation, Milford, MA) XBridge C18,150 mm 2.1 mm, 3.5 m particle size, or equivalent, has been found suitable foruse.7A Waters Quattro micro API mass spectrometer (a trademark of the WatersCorporation, Milford, MA), or equ
20、ivalent, was found suitable for use. Themulti-laboratory study included Applied Biosystems and Waters mass spectrom-eters.8A Millex HV Syringe Driven Filter Unit PVDF 0.45 m (MilliporeCorporation, Catalog # SLHV033NS; a trademark of the Waters Corporation,Milford, MA) has been found suitable for use
21、 for this test method, any filter unitmay be used that meets the performance of this test method may be used.9Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society,
22、see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 2 Concentrations of Calibration Standards (PPB)Analyte/Surrogate LV 1 LV 2 LV 3 LV 4 LV 5 LV 6Aldicarb
23、 1 5 10 25 50 100Carbofuran 1 5 10 25 50 100Oxamyl 1 5 10 25 50 100Methomyl 1 5 10 25 50 100BDMC (Surrogate) 2 10 20 50 100 200TABLE 3 Gradient Conditions for Liquid ChromatographyTime(min)Flow(L/min)PercentCH3CNPercent95 % Water 5%CH3CNPercent 50 mmolarNH4OAc/NH4OH in95 % Water/5 % CH3CN0 300 0 95
24、52 300 0 95 54 300 30 65 56 300 35 60 58 300 35 60 510 300 75 20 511.5 300 75 20 512 300 95 0 518 300 95 0 520 300 0 95 523 300 0 95 5D7600 16 (2017)411.1.3 Seal WashSolvent: 50 % Acetonitrile/50 % Water;Time: 5 minutes.11.1.4 Needle WashSolvent: 50 % Acetonitrile/50 % Wa-ter; Normal wash, approxima
25、tely 13 second wash time.11.1.5 Autosampler PurgeThree loop volumes.11.1.6 Specific instrument manufacturer wash/purge speci-fications should be followed in order to eliminate samplecarry-over in the analysis of carbamates.11.2 Mass Spectrometer Parameters:711.2.1 In order to acquire the maximum num
26、ber of datapoints per SRM channel while maintaining adequatesensitivity, the tune parameters may be optimized according toyour instrument. Each peak requires at least 10 scans per peakfor adequate quantitation. This standard contains only onesurrogate and four target compounds. The MRM experimentwin
27、dows were set to acquire methomyl and oxamyl in oneexperiment window while aldicarb, carbofuran and BDMC arein their individual MRM experiment windows. This is requiredbecause the chromatographic resolution separating oxamyl andmethomyl was not achieved. Variable parameters regardingretention times,
28、 SRM Transitions and cone and collisionenergies are shown in Table 4.The instrument is set in the Electrospray (+) positive setting.Capillary Voltage: 3.5 kVCone: Variable depending on analyte (Table 4)Extractor: 2 VoltsRF Lens: 0.2 VoltsSource Temperature: 120CDesolvation Temperature: 300CDesolvati
29、on Gas Flow: 500 L/hrCone Gas Flow: 25 L/hrLow Mass Resolution 1: 14.5High Mass Resolution 1: 14.5Ion Energy 1: 0.5Entrance Energy: 1Collision Energy: Variable depending on analyte (Table 4)Exit Energy: 2Low Mass Resolution 2: 15High Mass resolution 2: 15Ion Energy 2: 0.5Multiplier: 650Gas Cell Pira
30、ni Gauge: 3.3 103TorrInter-Channel Delay: 0.02 secondsInter-Scan Delay: 0.1 secondsRepeats: 1Span: 0 DaltonsDwell: 0.1 Seconds12. Calibration and Standardization12.1 The mass spectrometer must be calibrated per manu-facturer specifications before analysis. In order that analyticalvalues obtained usi
31、ng this test method are valid and accuratewithin the confidence limits of the test method, the followingprocedures must be followed when performing the test method.12.2 Calibration and StandardizationTo calibrate theinstrument, analyze six calibration standards containing the sixconcentration levels
32、 of the carbamates and BDMC surrogateprior to analysis as shown in Table 2. A calibration stockstandard solution is prepared from standard materials orpurchased as certified solutions. Stock standard solution A(Level 6) containing aldicarb, carbofuran, oxamyl, methomyland BDMC is prepared at Level 6
33、 concentration and aliquots ofthat solution are diluted to prepare Levels 1 through 5. Thefollowing steps will produce standards with the concentrationvalues shown in Table 2. The analyst is responsible forrecording initial component weights carefully when workingwith pure materials and correctly ca
34、rrying the weights throughthe dilution calculations.12.2.1 Prepare stock standard solution A (Level 6) byadding to a 100-mL volumetric flask individual methanolsolutions of the following: 50 L of aldicarb, carbofuran,oxamyl and methomyl each at 0.2 g/L and 50 L of BDMC at0.4 g/L, dilute to 100 mLwit
35、h 90 % water/10 % methanol. Thepreparation of the Level 6 standard can be accomplished usingdifferent volumes and concentrations of stock solutions as isaccustomed in the individual laboratory. Depending on stockconcentrations prepared, the solubility at that concentrationwill have to be ensured.12.
36、2.2 Aliquots of Solution A are then diluted with 90 %water/10 % methanol to prepare the desired calibration levelsin 2-mL amber glass LC vials. The calibration vials must beused within 24 hours to ensure optimum results. Stock calibra-tion standards are routinely replaced every 7 days if notprevious
37、ly discarded for quality control failure. Calibrationstandards are not filtered.12.2.3 Inject each standard and obtain a chromatogram foreach one. An external calibration technique is used monitoringthe primary and confirmatory SRM transition of each analyte.Calibration software is utilized to condu
38、ct the quantitation ofTABLE 4 Retention Times, SRM Ions, and Analyte-Specific Mass Spectrometer ParametersAnalyte Primary/ ConfirmatoryRetentiontime (min)Cone Voltage(Volts)Collision Energy (eV)SRM Mass Transition(Parent Product)Collision Energy(eV)AldicarbPrimary11.0010 7 208.2 115.92.12Confirmator
39、y 10 15 208.2 88.7CarbofuranPrimary12.8527 12 222.2 165.21.20Confirmatory 27 20 222.2 123OxamylPrimary8.2515 8 237.2 71.62.38Confirmatory 15 8 237.2 89.8MethomylPrimary8.4517 8 163.1 87.71.58Confirmatory 17 8 163.1 105.8BDMC (Surrogate)Primary14.5025 24 258.1 1221.31Confirmatory 25 9 258.1 201.2D760
40、0 16 (2017)5the target analytes and surrogate using the primary SRMtransition. The ratios of the primary/confirmatory SRM transi-tion area counts are given in Table 4. These are given asinformative and will vary depending on the individual tuningconditions. The primary/confirmatory SRM transition ar
41、earatio must be within 30 % of the individual labs acceptedprimary/confirmatory SRM transition area ratio. The primarySRM transition of each analyte is used for quantitation and theconfirmatory SRM transition for confirmation. This givesadded confirmation by isolating the parent ion, fragmenting iti
42、nto two product ions, and relating it to the retention time in thecalibration standard.12.2.4 The calibration software manual should be consultedto use the software correctly. The quantitation method is set asan external calibration using the peak areas in ppt or ppb unitsas long as the analyst is c
43、onsistent. Concentrations may becalculated using the data system software to generate linearregression or quadratic calibration curves. Forcing the calibra-tion through the origin is not recommended.12.2.5 Linear calibration may be used if the coefficient ofdetermination, r2, is 0.98 for the analyte
44、. The point of originis excluded and a fit weighting of 1/X is used in order to givemore emphasis to the lower concentrations. If one of thecalibration standards other than the high or low point causesthe r2of the curve to be 0.99 for the analyte. The point oforigin is excluded and a fit weighting o
45、f 1/X is used in order togive more emphasis to the lower concentrations. If one of thecalibration standards causes the curve to be 0.99. Inthis event, the reporting range must be modified to reflect thischange.12.2.7 The retention time window of the SRM transitionsmust be within 5 % of the retention
46、 time of the analyte in amidpoint calibration standard. If this is not the case, re-analyzethe calibration curve to determine if there was a shift inretention time during the analysis and the sample needs to bere-injected. If the retention time is still incorrect in the sample,refer to the analyte a
47、s an unknown.12.2.8 A midpoint calibration check standard must be ana-lyzed at the end of each batch of 20 samples or within 24 hoursafter the initial calibration curve was generated. This endcalibration check should be the same calibration standard thatwas used to generate the initial curve. The re
48、sults from the endcalibration check standard must have a percent deviation lessthan 30 % from the calculated concentration for the targetanalytes and surrogate. If the results are not within thesecriteria, the problem must be corrected and either: all samplesin the batch must be re-analyzed against
49、a new calibrationcurve, or the affected results must be qualified with anindication that they do not fall within the performance criteriaof the test method. If the analyst inspects the vial containingthe end calibration check standard and notices that the sampleevaporated affecting the concentration, a new end calibrationcheck standard may be made and analyzed. If this new endcalibration check standard has a percent deviation less than30 % from the calculated concentration for the target analytesand surrogate the results may be reported unqualif
