1、Designation: D 5790 95 (Reapproved 2006)Standard Test Method forMeasurement of Purgeable Organic Compounds in Water byCapillary Column Gas Chromatography/Mass Spectrometry1This standard is issued under the fixed designation D 5790; the number immediately following the designation indicates the year
2、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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the identification and simulta-n
3、eous measurement of purgeable volatile organic compounds.It has been validated for treated drinking water, wastewater,and ground water. This test method is not limited to theseparticular aqueous matrices; however, the applicability of thistest method to other aqueous matrices must be demonstrated.1.
4、2 This test method is applicable to a wide range of organiccompounds that have sufficiently high volatility and low watersolubility to be efficiently removed from water samples usingpurge and trap procedures. Table 1 lists the compounds thathave been validated for this test method.This test method i
5、s notlimited to the compounds listed in Table 1; however, theapplicability of the test method to other compounds must bedemonstrated.1.3 Analyte concentrations up to approximately 200 g/Lmay be determined without dilution of the sample. Analytesthat are inefficiently purged from water will not be de
6、tectedwhen present at low concentrations, but they can be measuredwith acceptable accuracy and precision when present in suffi-cient amounts.1.4 Analytes that are not separated chromatographically, butthat have different mass spectra and noninterfering quantitationions, can be identified and measure
7、d in the same calibrationmixture or water sample. Analytes that have very similar massspectra cannot be individually identified and measured in thesame calibration mixture or water sample unless they havedifferent retention times. Coeluting compounds with verysimilar mass spectra, such as structural
8、 isomers, must bereported as an isomeric group or pair.Two of the three isomericxylenes are examples of structural isomers that may not beresolved on the capillary column, and if not, must be reportedas an isomeric pair.1.5 It is the responsibility of the user to ensure the validityof this test meth
9、od for untested matrices.1.6 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.7 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
10、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:2D 1129 Terminology Relating to WaterD 2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of C
11、ommittee D19 on WaterD 3871 Test Method for Purgeable Organic Compounds inWater Using Headspace SamplingD 3973 Test Method for Low-Molecular Weight Haloge-nated Hydrocarbons in WaterD 4210 Practice for Intralaboratory Quality Control Proce-dures and a Discussion on Reporting Low-Level Data3E 355 Pra
12、ctice for Gas Chromatography Terms and Rela-tionships2.2 Other Document:Code of Federal Regulations, 40 CFR Part 26143. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method, referto Definitions D 1129 and Practice E 355.3.2 Definitions of Terms Specific to This Standard
13、:3.2.1 calibration standarda solution prepared from theprimary dilution standard solution and stock standard solutionsof the internal standards and surrogate analytes.The calibration1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommi
14、ttee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved Feb. 15, 2006. Published March 2006. Originallyapproved in 1995. Last previous edition approved in 2001 as D 5790 95 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM
15、Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Available from the Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20402.1Copyright ASTM International, 10
16、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.standards are used to calibrate the instrument response withrespect to analyte concentration.3.2.2 field duplicates two separate samples collected atthe same time and place under identical circumstances andtreated exac
17、tly the same throughout field and laboratoryprocedures. Analysis of field duplicates gives an indication ofthe precision associated with sample collection, preservation,and storage, as well as with laboratory procedures.3.2.3 field reagent blankreagent water placed in a samplecontainer, taken to the
18、 field along with the samples, and treatedas a sample in all respects, including exposure to sampling siteconditions, storage, preservation, and all analytical procedures.The purpose of the field reagent blank is to determine if testmethod analytes or other interferences are present in the fieldenvi
19、ronment.3.2.4 internal standarda pure analyte added to a solutionin a known amount, that is used to measure the relativeresponses of other test method analytes and surrogates that arecomponents of the same solution. The internal standard mustbe an analyte that is not a sample component.3.2.5 laborat
20、ory duplicatestwo sample aliquots taken inthe analytical laboratory and analyzed separately with identicalprocedures. Analysis of laboratory duplicates gives an indica-tion of the precision associated with laboratory procedures, butnot with sample collection, preservation, or storage procedures.3.2.
21、6 laboratory-fortified blankan aliquot of reagentwater to which known quantities of the test method analytes areadded in the laboratory. The laboratory-fortified blank isanalyzed exactly like a sample, and its purpose is to determinewhether the methodology is in control and whether thelaboratory is
22、capable of making accurate and precise measure-ments at the required detection limit.3.2.7 laboratory-fortified sample matrixan aliquot of anenvironmental sample to which known quantities of the testmethod analytes are added in the laboratory. The laboratory-fortified sample matrix is analyzed exact
23、ly like a sample, andits purpose is to determine whether or not the sample matrix orthe addition of preservatives or dechlorinating agents to thesample contributes bias to the analytical results. The back-ground concentrations of the analytes in the sample matrixmust be determined in a separate aliq
24、uot, and the measuredvalues in the laboratory-fortified sample matrix must becorrected for background concentrations.3.2.8 laboratory performance check solutiona solution ofone or more compounds (analytes, surrogates, internal stan-dard, or other test compounds) used to evaluate the perfor-mance of
25、the instrument system with respect to a defined set oftest method criteria.3.2.9 laboratory reagent blankan aliquot of reagent waterthat is treated exactly as a sample including exposure to allglassware, equipment, solvents, reagents, internal standards,and surrogates that are used with other sample
26、s. The laboratoryreagent blank is used to determine if test method analytes orother interferences are present in the laboratory environment,the reagents, or the apparatus.3.2.10 primary dilution standard solutiona solution ofseveral analytes prepared in the laboratory from stock standardsolutions an
27、d diluted as needed to prepare calibration solutionsand other needed analyte solutions.3.2.11 purgeable organicany organic material that isremoved from aqueous solution under the purging conditionsdescribed in this test method.3.2.12 quality control samplea sample matrix containingtest method analyt
28、es or a solution of method analytes in awater-miscible solvent that is used to fortify reagent water orenvironmental samples. The quality control sample is obtainedfrom a source external to the laboratory and is used to checklaboratory performance with externally prepared test materials.3.2.13 stock
29、 standard solutiona concentrated solutioncontaining a single certified standard that is a test methodanalyte prepared in the laboratory with an assayed referencecompound. Stock standard solutions are used to prepareprimary dilution standards. Commercially available stock stan-dard solutions may be u
30、sed.3.2.14 surrogate analytea pure analyte that is extremelyunlikely to be found in any sample, that is added to a samplealiquot in a known amount, and is measured with the sameprocedures used to measure other components. The purpose ofa surrogate analyte is to monitor test method performance withea
31、ch sample.4. Summary of Test Method4.1 Volatile organic compounds with low water-solubilityare purged from the sample matrix by bubbling an inert gasthrough the aqueous sample. Purged sample components aretrapped in a tube containing suitable sorbent materials. Whenpurging is complete, the sorbent t
32、ube is heated and backflushedwith inert gas to desorb the trapped sample components into acapillary gas chromatography (GC) column interfaced to amass spectrometer (MS). The GC column is temperatureprogrammed to separate the test method analytes which arethen detected with the MS. Compounds eluting
33、from the GCcolumn are identified by comparing their measured massspectra and retention times to reference spectra and retentiontimes in a database. Reference spectra and retention times foranalytes are obtained by the measurement of calibrationstandards under the same conditions used for the samples
34、. Theconcentration of each identified component is measured byrelating the MS response of the quantitation ion produced bythat compound to the MS response of the quantitation ionproduced by a compound that is used as an internal standard.Surrogate analytes, whose concentrations are known in everysam
35、ple, are measured with the same internal standard calibra-tion procedure.5. Significance and Use5.1 Purgeable organic compounds have been identified ascontaminants in treated drinking water, wastewater, groundwater, and Toxicity Characteristic Leaching Procedure (TCLP)leachate. These contaminants ma
36、y be harmful to the environ-ment and to people. Purge and trap sampling is a generallyapplicable procedure for concentrating these components priorto gas chromatographic analysis.D 5790 95 (2006)26. Interferences6.1 During analysis, major contaminant sources are volatilematerials in the laboratory a
37、nd impurities in the inert purginggas and in the sorbent trap. Avoid the use of plastic tubing orthread sealants other than PTFE, and avoid the use of flowcontrollers with rubber components in the purging device.These materials out-gas organic compounds that will beconcentrated in the trap during th
38、e purge operation. Analysesof laboratory reagent blanks provide information about thepresence of contaminants. When potential interfering peaks arenoted in laboratory reagent blanks, the analyst should changethe purge gas source and regenerate the molecular sieve purgegas filter. Reagents should als
39、o be checked for the presence ofcontaminants. Subtracting blank values from sample results isnot permitted.6.2 Interfering contamination may occur when a samplecontaining low concentrations of volatile organic compounds isanalyzed immediately after a sample containing higher con-centrations of volat
40、ile organic compounds. Experience gainedfrom the test method validation has shown that there is acarryover of approximately 2 % of the concentration of eachanalyte from one sample to the next. The effect was observedwhen samples containing 1 g/L of analyte were analyzedimmediately after samples cont
41、aining 20 g/L of analyte. Forthat reason, when low concentrations of analytes are measuredin a sample, it is very important to examine the results of thepreceding samples and interpret the low-concentration resultsaccordingly. One preventive technique is between-sample rins-ing of the purging appara
42、tus and sample syringes with twoportions of reagent water.After analysis of a sample containinghigh concentrations of volatile organic compounds, one ormore laboratory reagent blanks should be analyzed to check forcross contamination. After analyzing a highly contaminatedsample, it may be necessary
43、to use methanol to clean thesample chamber, followed by heating in an oven at 105C.6.3 Samples can be contaminated by diffusion of volatileorganics through the septum seal into the sample duringshipment and storage. The analytical and sample storage areashould be isolated from all atmospheric source
44、s of volatileorganic compounds, otherwise random background levels mayresult. Since methylene chloride will permeate through PTFEtubing, all gas chromatography carrier gas lines and purge gasplumbing should be constructed of stainless steel or coppertubing. Personnel who have been working directly w
45、ith sol-vents such as those used in liquid/liquid extraction proceduresshould not be allowed into the analytical area until they havewashed and changed their clothing.TABLE 1 Compounds Validated for This Test MethodCompound CAS Registry Number Primary Quantitation IonSecondary QuantitationIonApproxi
46、mate ElutionOrderBenzene 71-43-2 78 77 20Bromobenzene 108-86-1 156 77, 158 44Bromochloromethane 74-97-5 128 49, 130 16Bromodichloromethane 75-27-4 83 85, 127 25Bromoform 75-25-2 173 175, 252 41Bromomethane 74-83-9 94 96 4n-butylbenzene 104-51-8 91 134 57sec-butylbenzene 135-98-8 105 134 53tert-butyl
47、benzene 98-06-6 119 91 52Carbon disulfide 75-15-0 76 78 8Carbon tetrachloride 56-23-5 117 119 19Chlorobenzene 108-90-7 112 77, 114 35Chloroethane 75-00-3 64 66 5Chloroform 67-66-3 83 85 15Chloromethane 74-87-3 50 52 22-chlorotoluene 95-49-8 91 126 474-chlorotoluene 106-43-4 91 126 50Dibromochloromet
48、hane 124-48-1 129 127 331,2-dibromo-3-chloropropane 96-12-8 75 155, 157 601,2-dibromoethane 106-93-4 107 109, 188 34Dibromomethane 74-95-3 93 95, 174 261,2-dichlorobenzene 95-50-1 146 111, 148 581,3-dichlorobenzene 541-73-1 146 111, 148 541,4-dichlorobenzene 106-46-7 146 111, 148 56trans-1,4-dichlor
49、o-2-butene 110-57-6 75 53, 89 48Dichlorodifluoromethane 75-71-8 85 87 11,1-dichloroethane 75-34-3 63 65, 83 111,2-dichloroethane 107-06-2 62 98 211,1-dichloroethene 75-35-4 96 61, 63 7cis-1,2-dichloroethene 156-59-4 96 61, 98 13trans-1,2-dichloroethene 156-60-5 96 61, 98 101,2-dichloropropane 78-87-5 63 112 241,3-dichloropropane 142-28-9 76 78 322,2-dichloropropane 590-20-7 77 97 121,1-dichloropropene 563-58-6 75 110, 77 18cis-1,3-dichloropropene 10061-01-5 75 110 27trans-1,3-dichloropropene 10061-02-6 75 110 29Ethylbenzene 100-41-4 91 106 36Hexachlorobutadiene 87-6
