Purge and Trap GC-MS Determination of Trace Volatile Compounds in Drinking Water Using the HP 5973 Series MSD and Volatiles Interface (5965-8105E)

A system of purge and trap (P&T), gas chromatography (GC), and mass spectrometry (MS) was used to determine 84 volatile organic compounds at the ppt (parts per trillion) level targeted by EPA method 524.2. This was accomplished without the use of cryofocusing. The optimized system consisted of an HP 7695 P&T concentrator and autosampler; an HP 6890 Series GC with a volatiles interface (VI); a wide-bore capillary column; and an HP 5973 mass selective dectector (MSD) with turbo pump. Without using cryofocusing, results for drinking water pollutants showed that this system exceeded the detection limit requirements for all 84 compounds listed. For example, all 14 aromatic compounds and 41 of 46 halogenated hydrocarbons listed in EPA method 524.2 were quantitated at 10 ppt or lower with a signal-to-noise ratio greater than five. Of the 29 remaining compounds in EPA method 524.2, all but four polar analytes were quantitated at 50 ppt; the four polar compounds were quantitated at 100 ppt.