Improved Analysis of MTBE, TAME, and TBA in Petroleum Fuel-Contaminated Groundwater by SPME Using Deuterated Internal Standards with GC−MS

Abstract

An improved method is described for the routine analysis of methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), and tert-butyl alcohol (TBA) in petroleum fuel-contaminated groundwater samples using solid-phase microextraction (SPME) and deuterated internal standards combined with gas chromatography mass spectrometry (GC-MS). Factors affecting method performance (SPME fiber selection, headspace or liquid extraction, extraction time, calibration conditions, salt addition, method sensitivity, and matrix effects) are evaluated using groundwater samples from a chalk aquifer contaminated with petroleum fuel containing MTBE, TAME, and TBA. The detection sensitivity and analytical efficiency of the method was optimized for these compounds using a PDMS-Carboxen fiber, sample NaCl content of 25% (w/v), and extraction time of 30 min. Internal calibration standards (deuterated MTBE and TBA) are necessary to control extraction errors during analysis. SPME extraction efficiency and detection sensitivity for ...