1、Designation: D7645 14Standard Test Method forDetermination of Aldicarb, Aldicarb Sulfone, AldicarbSulfoxide, Carbofuran, Methomyl, Oxamyl, and Thiofanox inWater by Liquid Chromatography/Tandem MassSpectrometry (LC/MS/MS)1This standard is issued under the fixed designation D7645; the number immediate
2、ly following the designation indicates the year oforiginal 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 proc
3、edure covers the determination of aldicarb,aldicarb sulfone, aldicarb sulfoxide, carbofuran, methomyl,oxamyl, and thiofanox (referred to collectively as carbamatesin this test method) in water by direct injection using liquidchromatography (LC) and detected with tandem mass spec-trometry (MS/MS). Th
4、ese analytes are qualitatively and quan-titatively determined by this method. This test method adheresto multiple reaction monitoring (MRM) mass spectrometry.1.2 The Detection Verification Level (DVL) and ReportingRange for the carbamates are listed in Table 1.1.2.1 The DVL is required to be at a co
5、ncentration 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 reaction monitoring (SRM)transitions, and Fig. 2 displays the confirmatory SRM transi-tions at the DVLs for the carbamates.1.2.2 The
6、 reporting limit is the concentration of the Level 1calibration standard as shown in Table 2 for the carbamates.1.3 UnitsThe values stated in SI units are to be regardedas standard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesaf
7、ety 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.2. Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to W
8、aterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD3694 Practices for Preparation of Sample Containers andfor Preservation of Organic ConstituentsD3856 Guide for Management Systems in LaboratoriesEngaged
9、 in Analysis of WaterD4841 Practice for Estimation of Holding Time for WaterSamples Containing Organic and Inorganic ConstituentsD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisE2554 Practice for Estimating and Monitoring the Uncer-tainty of Test
10、Results of a Test Method Using ControlChart Techniques2.2 Other Documents:3EPA Publication SW-846 Test Methods for Evaluating SolidWaste, Physical/Chemical MethodsEPA Method 531 Measurement of N-Methyl Carbamoylox-imes and N-Methyl Carbamates in Drinking Water byDirect Aqueous Injection HPLC with Po
11、st Column De-rivatizationEPA Method 531.2 Measurement ofN-Methylcarbamoyloximes and N-Methylcarbamates inWater by Direct Aqueous Injection HPLC with Postcol-umn Derivatization1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D1
12、9.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved Jan. 1, 2014. Published March 2014. Originallyapproved in 2010. Last previous edition approved in 2010 as D7645 101. DOI:10.1520/D7645-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontac
13、t ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from National Technical Information Service (NTIS), U.S. Depart-ment of Commerce, 5285 Port Royal Road, Springfield, VA, 22161 o
14、r 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 States1EPA Method 538 Determination of Selected Organic Con-taminants in Drinking Water by DirectAqueous Injection-Liquid Chromatogr
15、aphy/Tandem Mass Spectrometry(DAI-LC/MS/MS)3. Terminology3.1 Definitions:3.1.1 carbamates, nin this test method, aldicarb, aldicarbsulfone, aldicarb sulfoxide, carbofuran, methomyl, oxamyl,and thiofanox collectively.3.1.2 detection verification level, DVL, na concentrationthat has a signal/noise rat
16、io greater than 3:1 and is at least 3times below the Reporting Limit (RL).3.1.3 reporting limit, RL, nthe concentration of thelowest-level calibration standard used for quantification.3.2 Abbreviations:3.2.1 mMmillimolar,110-3moles/L3.2.2 NDnon-detect3.2.3 pptparts per trillion, ng/L4. Summary of Te
17、st Method4.1 This is a performance-based method, and modificationsare allowed to improve performance.4.2 For carbamate analysis, samples are shipped to the labacidified between 0C and 6C and analyzed within 14 days ofcollection. In the lab, the samples are spiked with surrogates,filtered using a syr
18、inge driven filter unit, and analyzed directlyby LC/MS/MS.4.3 The carbamates, methomyl-13C2,15N (surrogate) andcarbofuran-13C6(surrogate) are identified by retention time andtwo SRM transitions. The target analytes and surrogate arequantitated using the primary SRM transitions utilizing anexternal c
19、alibration. The final report issued for each samplelists the concentration of carbamates and the surrogate recov-eries.5. Significance and Use5.1 This test method has been developed by U.S. EPARegion 5 Chicago Regional Laboratory (CRL).5.2 The N-methyl carbamate (NMC) pesticides: aldicarb,carbofuran
20、, methomyl, oxamyl, and thiofanox have been iden-tified by EPAas working through a common mechanism.Theseaffect the nervous system by reducing the ability of enzymes.Enzyme inhibition was the primary toxicological effect ofregulatory concern to EPA in assessing the NMCs food,drinking water, and resi
21、dential risks. In most of the country,NMC residues in drinking water sources are at levels that arenot likely to contribute substantially to the multi-pathwaycumulative exposure. Shallow private wells extending throughhighly permeable soils into shallow, acidic ground waterrepresent what the EPA bel
22、ieves to be the most vulnerabledrinking water. Aldicarb sulfone and aldicarb sulfoxide arebreakdown products of aldicarb and should also be monitoreddue to their toxicological effects.45.3 This test method has been investigated for use withreagent, surface, and drinking water for the selected carbam
23、-ates: aldicarb, aldicarb sulfone, aldicarb sulfoxide, carbofuran,methomyl, oxamyl, and thiofanox.6. Interferences6.1 Method interferences may be caused by contaminants insolvents, reagents, glassware, and other apparatus producingdiscrete artifacts or elevated baselines. All of these materialsare d
24、emonstrated to be free from interferences by analyzinglaboratory reagent blanks under the same conditions assamples.6.2 All glassware is washed in hot water with detergent andrinsed in hot water followed by distilled water. The glasswareis then dried and heated in an oven at 250C for 15 to 30minutes
25、. All glassware is subsequently cleaned with acetonefollowed by methanol.6.3 All reagents and solvents should be pesticide residuepurity or higher to minimize interference problems.6.4 Matrix interferences may be caused by contaminants inthe sample. The extent of matrix interferences can varyconside
26、rably from sample source depending on variations ofthe sample matrix.7. Apparatus7.1 LC/MS/MS System:7.1.1 Liquid Chromatography (LC) SystemAcomplete LCsystem is needed in order to analyze samples.5,6Any systemthat is capable of performing at the flows, pressures, controlledtemperatures, sample volu
27、mes, and requirements of the stan-dard may be used.7.1.2 Analytical ColumnWatersACQUITY UPLC BEHC18, 2.1 100 mm, 1.7 m particle size 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
28、 used and need to be moni-tored.4Additional information about Carbamate pesticides can be found on the Internetat http:/www.epa.gov (2010).5An ACQUITY UltraPerformance Liquid Chromatography (UPLC) (trade-mark6) System was used to develop this test method. All parameters in this testmethod are based
29、on this system and may vary depending on your instrument.6The ACQUITY UltraPerformance Liquid Chromatography (UPLC) trademarkis owned by Waters Technologies Corporation in Wilmington, DE.TABLE 1 Detection Verification Level and Reporting RangeAnalyteDVL(ng/L)Reporting Range(g/L)Aldicarb 250 1-100Ald
30、icarb Sulfone 250 1-100Aldicarb Sulfoxide 250 1-100Carbofuran 250 1-100Methomyl 250 1-100Oxamyl 250 1-100Thiofanox 250 1-100D7645 142FIG. 1 Example Primary SRM Chromatograms Signal/Noise RatiosFIG. 2 Example Confirmatory SRM Chromatograms Signal/Noise RatiosD7645 1437.2 Tandem Mass Spectrometer (MS/
31、MS) SystemAMS/MS system capable of MRM analysis.7,87.3 Filtration Device:7.3.1 Hypodermic SyringeA Lock Tip Glass Syringe ca-pable of holding a Millex (trademark9) HV Syringe DrivenFilter Unit PVDF 0.22 m or similar may be used.7.3.1.1 A 25 mL Lock Tip Glass Syringe size is recom-mended since a 25 m
32、L sample size is used in this test method.7.3.2 FilterMillex HV Syringe Driven Filter Unit PVDF0.22 m10or similar may be used.8. Reagents and Materials8.1 Purity of ReagentsHigh Performance Liquid Chroma-tography (HPLC) pesticide residue analysis and spectropho-tometry grade chemicals shall be used
33、in all tests. Unlessindicated otherwise, it is intended that all reagents shallconform to the Committee on Analytical Reagents of theAmerican Chemical Society.11Other reagent grades may beused provided they are first determined to be of sufficientlyhigh purity to permit their use without affecting t
34、he accuracy ofthe measurements.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Type 1 of Specification D1193. It must be demonstrated thatthis water does not contain contaminants at concentrationssufficient to interfere with th
35、e analysis.8.3 GasesUltrapure nitrogen and argon.8.4 Acetonitrile (CAS # 75-05-8).8.5 Methanol (CAS # 67-56-1).8.6 Acetone (CAS # 67-64-1).8.7 Ammonium Formate (CAS # 540-69-2).8.8 Acetic Acid (Glacial, CAS # 64-19-7).8.9 Aldicarb (CAS # 116-06-3).8.10 Aldicarb Sulfone (CAS # 1646-88-4).8.11 Aldicar
36、b Sulfoxide (CAS # 1646-87-3).8.12 Carbofuran (CAS # 1563-66-2).8.13 Oxamyl (CAS # 23135-22-0).8.14 Methomyl (CAS # 16752-77-5).8.15 Thiofanox (CAS # 39196-18-4).8.16 Methomyl-13C2,15N (acetohydroxamate-13C2,15N,CAS # (unlabeled) 16752-77-5).128.17 Carbofuran-13C6(Ring-13C6, CAS # (unlabeled) 1563-6
37、6-2).129. Hazards9.1 Normal laboratory safety applies to this test method.Analysts should wear safety glasses, gloves, and lab coatswhen working in the lab. Analysts should review the MaterialSafety Data Sheets (MSDS) for all reagents used in this testmethod.10. Sampling10.1 Sampling and Preservatio
38、nGrab samples should becollected in 25 mL pre-cleaned amber glass bottles withTeflon (trademark13) lined caps demonstrated to be free ofinterferences. All samples are acidified with glacial acetic acidto pH 3.8 upon collection.Afew drops or less of glacial aceticacid is required per 40 mL water samp
39、le collected. Chlorinateddrinking water samples are also dechlorinated with ascorbicacid; 10 mg of ascorbic acid is added to each 40 mL volume ofwater prior to collection. Drinking water samples must bedechlorinated upon collection.Aldicarb oxidizes when residualchlorine is present in the sample. Th
40、is test method is based ona 25 mL sample size per analysis. If different sample sizes areused, spiking solution amounts and preservatives will need to7AQuattro Premier XE (trademark8) tandem quadrupole mass spectrometer wasused to develop this test method.All parameters in this test method are based
41、 on thissystem and may vary depending on your instrument.8The Quattro Premier XE trademark is owned by Waters Technologies Corpo-ration in Wilmington, DE.9The Millex trademark is owned by Merck KGaA in Darmstadt, Germany10The sole source of supply of the apparatus known to the committee at this time
42、is Millipore Corporation, Catalog # SLGV033NS. If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.11Reagent Chemicals, A
43、merican Chemical Society Specifications, AmericanChemical Society, Washington, D.C. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia andNational Formu
44、lators, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.12The sole source of supply of the labeled carbamates known to the committeeat this time is Cambridge Isotope Laboratories, 50 Frontage Road, Andover, MA01810-5413. If you are aware of alternative suppliers, please provide this informa
45、-tion to ASTM International Headquarters. Your comments will receive carefulconsideration at a meeting of the responsible technical committee,1which you mayattend.13The Teflon trademark is owned by E. I. du Pont de Nemours and Company inWilmington, DE.TABLE 2 Concentrations of Calibration Standards
46、(PPB)Analyte/Surrogate LV 1 LV 2 LV 3 LV 4 LV 5 LV 6 LV 7 LV 8Aldicarb 1 5 10 25 35 50 75 100Aldicarb Sulfone 1 5 10 25 35 50 75 100Aldicarb Sulfoxide 1 5 10 25 35 50 75 100Carbofuran 1 5 10 25 35 50 75 100Methomyl 1 5 10 25 35 50 75 100Oxamyl 1 5 10 25 35 50 75 100Thiofanox 1 5 10 25 35 50 75 100Ca
47、rbofuran-13C6(Surrogate) 1 5 10 25 35 50 75 100Methomyl-13C2,15N (Surrogate) 1 5 10 25 35 50 75 100D7645 144be modified. Conventional sampling practices should be fol-lowed. Refer to Guide D3856 and Practices D3694. Storesamples between 0C and 6C from the time of collection untilanalysis. Analyze th
48、e sample within 14 days of collection.NOTE 1Less sample volume is acceptable, but the spike amounts andsample preservatives must be adjusted accordingly.10.1.1 EPAMethod 531.2 demonstrated that carbamates aremore stable under acidic conditions. Potassium dihydrogencitrate buffer is used in Method 53
49、1.2 to bring the pH to 3.8,but this buffer is incompatible with LC/MS/MS. Therefore, thepH adjustment is accomplished with acetic acid in this testmethod. EPA Method 531.2 demonstrated that carbamatesunder acidic conditions are stable for at least 28 days. EPAMethod 531 demonstrated that oxamyl and methomyl arestable for at least 70 days at pH 3 6 0.2. Holding time isdependent upon your individual matrix and will vary. PracticeD4841 may be used to conduct a holding time study on yourindividual matrix.11. Preparation of LC/MS/MS11.1 LC Chromat
