1、Designation: D5317 98 (Reapproved 2017)Standard Test Method forDetermination of Chlorinated Organic Acid Compounds inWater by Gas Chromatography with an Electron CaptureDetector1This standard is issued under the fixed designation D5317; the number immediately following the designation indicates the
2、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 test method covers a gas chromatographic proce-
3、dure for the quantitative determination of selected chlorinatedacids and other acidic herbicides in water. Similar chemicalsmay also be determined by this test method, but it is the usersresponsibility to verify the applicability of this test method toany compounds not listed in this scope. The acid
4、 form of thefollowing compounds were interlaboratory tested using thistest method, and the results were found acceptable:2AnalyteChemical Abstract ServicesRegistry NumberBentazon 25057-89-02,4-D 94-75-72,4-DB 94-82-6DCPA acid metabolites2Dicamba 1918-00-93,5-Dichlorobenzoic acid 51-36-5Dichlorprop 1
5、20-36-55-Hydroxydicamba 7600-50-2Pentachlorophenol (PCP) 87-86-5Picloram 1918-02-12,4,5-T 93-76-52,4,5-TP (Silvex) 93-72-11.2 This test method may be applicable to the determinationof salts and esters of analyte compounds. The form of each acidis not distinguished by this test method. Results are ca
6、lculatedand reported for each listed analyte as the total free acid.1.3 This test method has been validated in an interlaboratorytest for reagent water and finished tap water. The analyst shouldrecognize that precision and bias reported in Section 18 maynot be applicable to other waters.1.4 This tes
7、t method is restricted to use by or under thesupervision of analysts experienced in the use of gas chroma-tography (GC) and in the interpretation of gas chromatograms.Each analyst must demonstrate the ability to generate accept-able results with this test method using the procedure describedin 19.3.
8、 It is the users responsibility to ensure the validity ofthis test method for waters of untested matrices.1.5 Analytes that are not separated chromatographically,that is, which have very similar retention times, cannot beindividually identified and measured in the same calibrationmixture or water sa
9、mple unless an alternate technique foridentification and quantitation exists (16.6, 16.7, and 16.8).1.6 When this test method is used to analyze unfamiliarsamples for any or all of the analytes given in 1.1, analyteidentifications must be confirmed by at least one additionalqualitative technique.1.7
10、 The values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.8 This standard does not purport to address all of thesafety concerns, if any, assoc
11、iated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific warning statements, see Sections 6, 8, 9, and 10.1.9 This international
12、standard was developed in accor-dance with internationally 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.
13、2. Referenced Documents2.1 ASTM Standards:3D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water1This test method is under the jurisdiction of ASTM Committee D19 on Waterand i
14、s the direct responsibility of Subcommittee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved Dec. 15, 2017. Published January 2018. Originallyapproved in 1992. Last previous edition approved in 2011 as D5317 93 (2011).DOI: 10.1520/D5317-98R17.2DCPA monoacid and d
15、iacid metabolites are included in the scope of this testmethod; DCPA diacid metabolite is used for validation studies.3For 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 t
16、o the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established
17、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.1D3370 Practices for Sampling Water from Closed ConduitsD3856 Guide for Management Systems in LaboratoriesEngaged
18、 in Analysis of WaterD4210 Practice for Intralaboratory Quality Control Proce-dures and a Discussion on Reporting Low-Level Data(Withdrawn 2002)4D5789 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Organic Constituents(Withdrawn 2002)42.2 EPA Standard:5Method 515.1
19、Revision 4.0, Methods for the Determinationof Organic Compounds in Drinking Water2.3 OSHA Standard:629 CFR 1910 OSHA Safety and Health Standards, GeneralIndustry3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard, refer toTerminology D1129.3.2 Definitions of Terms Spec
20、ific to This Standard:3.2.1 internal standard, na pure analyte(s) added to asolution in known amount(s) and used to measure the relativeresponses of other method analytes and surrogates that arecomponents of the same solution.3.2.1.1 DiscussionThe internal standard must be an ana-lyte that is not a
21、sample component.3.2.2 surrogate analyte, na pure analyte(s), which isextremely unlikely to be found in any sample, and which isadded to a sample aliquot in known amount(s) before extrac-tion and is measured with the same procedures used to measureother sample components.3.2.2.1 DiscussionThe purpos
22、e of a surrogate analyte is tomonitor method performance with each sample.4. Summary of Test Method4.1 The compounds listed in 1.1, in water samples, areconverted into sodium salts by adjusting the pH to 12 withsodium hydroxide solution (240 g/L) and shaking for 1 h.Extraneous neutral material is re
23、moved by extraction withmethylene chloride. The sample is acidified, the acids areextracted with ethyl ether and converted to methyl esters usingdiazomethane. After the excess reagent is removed, the methylesters are determined by capillary column GC using an electroncapture (EC) detector. Other det
24、ection systems, such as micro-coulometric and electrolytic conductivity, are not as sensitiveas EC for measurement of chlorinated acid esters but are morespecific and less subject to interferences. A mass spectrometermay also be used as a detector.4.2 This test method provides a magnesium silicate7c
25、leanup procedure to aid in the elimination of interferences thatmay be present.5. Significance and Use5.1 Chlorinated phenoxyacid herbicides, and other organicacids are used extensively for weed control. Esters and salts of2,4-D and silvex have been used as aquatic herbicides in lakes,streams, and i
26、rrigation canals. Phenoxy acid herbicides can betoxic even at low concentrations. For example, the 96 h, TLmfor silvex is 2.4 mg/L for bluegills (1).8These reasons makeapparent the need for a standard test method for such com-pounds in water.6. Interferences6.1 Method interferences may be caused by
27、contaminants insolvents, reagents, glassware and other sample processingapparatus that lead to discrete artifacts or elevated baselines ingas chromatograms. All reagents and apparatus must be rou-tinely demonstrated to be free from interferences under theconditions of the analysis by running laborat
28、ory reagent blanksas described in 19.2.6.1.1 Glassware must be scrupulously cleaned (2). Clean allglassware as soon as possible after use by thoroughly rinsingwith the last solvent used in it. Follow by washing with hotwater and detergent and thoroughly rinsing with dilute acid,tap, and reagent wate
29、r. Drain dry, and heat in an oven or mufflefurnace at 400C for 1 h. Do not heat volumetric ware.Thorough rinsing with acetone may be substituted for theheating. After drying and cooling, seal and store glassware ina clean environment to prevent any accumulation of dust orother contaminants. Store in
30、verted or capped with aluminumfoil. Thermally stable materials such as PCBs may not beeliminated by this treatment.6.1.2 The use of high purity reagents and solvents helps tominimize interference problems. Purification of solvents bydistillation in all-glass systems may be required. (WarningWhen a s
31、olvent is purified, stabilizers added by the manufac-turer are removed, thus potentially making the solvent hazard-ous. Also, when a solvent is purified, preservatives added bythe manufacturer are removed, thus potentially reducing theshelf-life.)6.2 The acid forms of the analytes are strong organic
32、 acidsthat react readily with alkaline substances and can be lostduring sample preparation. Glassware and glass wool must beacid-rinsed with hydrochloric acid (1 + 9) and the sodiumsulfate must be acidified with sulfuric acid prior to use to avoidanalyte loses due to adsorption.6.3 Organic acids and
33、 phenols, especially chlorinatedcompounds, cause the most direct interference with the deter-mination. Alkaline hydrolysis and subsequent extraction of thebasic sample removes many chlorinated hydrocarbons andphthalate esters that might otherwise interfere with the electroncapture analysis.4The last
34、 approved version of this historical standard is referenced onwww.astm.org.5Available from United States Environmental ProtectionAgency (EPA), WilliamJefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460,http:/www.epa.gov.6Available from U.S. Government Printing Office, Superinte
35、ndent ofDocuments, 732 N. Capitol St., NW, Washington, DC 20401-0001, http:/www.access.gpo.gov.7Florisil, a trademark of, and available from, Floridin Co., 2 Gateway Center,Pittsburgh, PA15222, or its equivalent, has been found satisfactory for this purpose.8The boldface numbers in parentheses refer
36、 to the list of references at the end ofthis test method.D5317 98 (2017)26.4 Interferences by phthalate esters can pose a majorproblem in pesticide analysis when using the ECD. Thesecompounds generally appear in the chromatogram as largepeaks. Common flexible plastics contain varying amounts ofphtha
37、lates, which are easily extracted or leached during labo-ratory operations. Cross contamination of clean glasswareroutinely occurs when plastics are handled during extractionsteps, especially when solvent-wetted surfaces are handled.Interferences from phthalates can best be minimized by avoid-ing th
38、e use of plastics in the laboratory. Exhaustive purificationof reagents and glassware may be required to eliminatebackground phthalate contamination (3).6.5 Interfering contamination may occur when a samplecontaining low concentrations of analytes is analyzed imme-diately following a sample containi
39、ng relatively high concen-trations of analytes. Between-sample rinsing of the samplesyringe and associated equipment with methyl-t-butyl-ether(MTBE) can minimize sample cross contamination. Afteranalysis of a sample containing high concentrations ofanalytes, one or more injections of MTBE should be
40、made toensure that accurate values are obtained for the next sample.6.6 Matrix interferences may be caused by contaminantsthat are coextracted from the sample. Also, note that allanalytes listed in Table 1 are not resolved from each other onany one column, that is, one analyte of interest may be ani
41、nterferent for another analyte of interest. The extent of matrixinterferences will vary considerably from source to source,depending upon the water sampled. The procedures in Section16 can be used to overcome many of these interferences.Positive identifications should be confirmed. See 16.6, 16.7,an
42、d 16.8.6.7 It is important that samples and working standards becontained in the same solvent. The solvent for workingstandards must be the same as the final solvent used in samplepreparation. If this is not the case, chromatographic compara-bility of standards to sample may be affected.7. Apparatus
43、 and Equipment7.1 Sample BottleBorosilicate amber, 1-L volume withgraduations, fitted with screw caps lined with TFE-fluorocarbon. Protect samples from light. The container mustbe washed and dried as described in 6.1.1 before use tominimize contamination. Cap liners are cut to fit from sheetsand ext
44、racted with methanol overnight prior to use.7.2 Glassware.7.2.1 Separatory funnel, 2000-mL, with TFE-fluorocarbonstopcocks, ground glass or TFE-fluorocarbon stoppers.7.2.2 Tumbler bottle, 1.7-L with TFE-fluorocarbon linedscrew cap. Cap liners are cut to fit from sheets and extractedwith methanol ove
45、rnight prior to use.7.2.3 Concentrator tube, Kuderna-Danish (K-D), 10 or25-mL, graduated. Calibration must be checked at the volumesemployed in the procedure. Ground-glass stoppers are used toprevent evaporation of extracts.7.2.4 Evaporative flask, K-D, 500-mL. Attach to concentra-tor tube with spri
46、ngs.7.2.5 Snyder column, K-D, three ball macro.7.2.6 Snyder column, K-D, two ball micro.7.2.7 Flask, round bottom, 500-mL with 24/40 ground glassjoint.7.2.8 Vials, glass, 5 to 10-mL capacity with TFE-fluorocarbon lined screw cap.7.3 Boiling Stone, TFE-fluorocarbon.7.4 Water Bath, heated, capable of
47、temperature control(62C). The bath should be used in a hood.7.5 Diazomethane GeneratorAssemble from two 20- by155-mm test tubes, two neoprene rubber stoppers, and a sourceof nitrogen as shown in Fig. 1.7.6 Glass Wool, acid washed and heated at 450C.TABLE 1 Retention Times and Estimated Method Detect
48、ionLimits for Method AnalytesAnalyte CAS No.Retention TimeA(min)EDLBPrimary Confirmation3,5-Dichlorobenzoic acid 51-36-5 18.6 17.7 0.061DCAA (surrogate) 19719-28-9 22.0 14.9 .Dicamba 1918-00-9 22.1 22.6 0.081Dichlorprop 120-36-5 25.0 25.6 0.262,4-D 94-75-7 25.5 27.0 0.2DBOB (int. std.) 10386-84-2 27
49、.5 27.6 .Pentachlorophenol 87-86-5 28.3 27.0 0.0762,4,5-TP 93-72-1 29.7 29.5 0.0755-Hydroxydicamba 7600-50-2 30.0 30.7 0.042,4,5-T 93-76-5 30.5 30.9 0.082,4-DB 94-82-6 32.2 32.2 0.8Bentazon 25057-89-0 33.3 34.6 0.2Picloram 1918-02-1 34.4 37.5 0.14DCPA acid metabolitesC. 35.8 37.8 0.02AColumns and analytical conditions are described in 7.7.1 and 7.7.2BEstimated method detection limit, g/L, determined from 7 replicate analyses ofa reagent water fortified with analyte at a concentration level yielding signal-to-noise of 5:1. EDL is defined as the standard deviation stu
