New drinking water regulations require the monitoring of eight volatile organic compounds that have established maximum contaminant levels (MCLs) and 51 other volatile organics for which MCLs are not established. A laboratory analytical method (Method 524.2) for the determination of 58 of these compounds is investigated, and precision and accuracy data are obtained. The method uses a standard inert gas purge extraction, isolation of the volatile organics on a three-stage solid-phase trap, thermal desorption into a gas chromatograph, separation with a fused-silica capillary column, and identification and measurement with a relatively low cost, benchtop ion trap detector that functions as a mass spectrometer. At a concentration of 2 μg/L (2 parts per billion), the grand mean measurement accuracy for 54 compounds was 95% of the true value with a mean relative standard deviation (RSD) of 4%. At 0.2 μg/L (200 parts per trillion), the grand mean measurement accuracy for 52 compounds was 95% of the true value with a mean RSD of 3%.; New drinking water regulations require the monitoring of eight volatile organic compounds that have established maximum contaminant levels (MCLs) and 51 other volatile organics for which MCLs are not established. A laboratory analytical method (Method 524.2) for the determination of 58 of these compounds is investigated, and precision and accuracy data are obtained. The method uses a standard inert gas purge extraction, isolation of the volatile organics on a three-stage solid-phase trap, thermal desorption into a gas chromatograph, separation with a fused-silica capillary column, and identification and measurement with a relatively low cost, benchtop ion trap detector that functions as a mass spectrometer. At a concentration of 2 μg/L (2 parts per billion), the grand mean measurement accuracy for 54 compounds was 95% of the true value with a mean relative standard deviation (RSD) of 4%. At 0.2 μg/L (200 parts per trillion), the grand mean measurement accuracy for 52 compounds was 95% of the true value with a mean RSD of 3%.
