ASTM D5790 – Standard Test Method for Measurement of Purgeable Organic Compounds in Water by Capillary Column Gas Chromatography/Mass Spectrometry
Significance and Use
5.1 Purgeable organic compounds have been identified as contaminants in treated drinking water, wastewater, ground water, and Toxicity Characteristic Leaching Procedure (TCLP) leachate. These contaminants may be harmful to the environment and to people. Purge and trap sampling is a generally applicable procedure for concentrating these components prior to gas chromatographic analysis.
1.1 This test method covers the identification and simultaneous 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 these particular aqueous matrices; however, the applicability of this test method to other aqueous matrices must be demonstrated.
1.2 This test method is applicable to a wide range of organic compounds that have sufficiently high volatility and low water solubility to be efficiently removed from water samples using purge and trap procedures. Table 1 lists the compounds that have been validated for this test method. This test method is not limited to the compounds listed in Table 1; however, the applicability of the test method to other compounds must be demonstrated.
1.3 Analyte concentrations up to approximately 200 μg/L may be determined without dilution of the sample. Analytes that are inefficiently purged from water will not be detected when present at low concentrations, but they can be measured with acceptable accuracy and precision when present in sufficient amounts.
1.4 Analytes that are not separated chromatographically, but that have different mass spectra and non-interfering quantitation ions, can be identified and measured in the same calibration mixture or water sample. Analytes that have very similar mass spectra cannot be individually identified and measured in the same calibration mixture or water sample unless they have different retention times. Coeluting compounds with very similar mass spectra, such as structural isomers, must be reported as an isomeric group or pair. Two of the three isomeric xylenes are examples of structural isomers that may not be resolved on the capillary column, and if not, must be reported as an isomeric pair.
1.5 It is the responsibility of the user to ensure the validity of this test method for untested matrices.
1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.