Thin-film microextraction combined with comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry screening for presence of multiclass organic pollutants in drinking water samples.

Abstract

Organic compounds in drinking water can be potentially hazardous. In this study, we demonstrate for the first time that combining in-bottle thin-film microextraction (TFME), comprehensive two-dimensional gas chromatography, and time-of-flight mass spectrometry (GC×GC-TOFMS) can produce a powerful, green tool for determining multiple organic pollutants in drinking water and monitoring changes in water samples after treatment with a water purification system. In the developed approach, water is added to an amber sampling bottle containing TFME membranes and left to sit until equilibration is achieved. Once equilibration has been achieved, the membranes are withdrawn, and the extracted compounds are quantified via thermal desorption in the GC×GC-TOFMS system. This approach enabled a large number of organic compounds with a wide range of physicochemical properties to be identified based on their mass spectra. A series of drinking water samples (raw water, water after softener filter, and drinking water) were collected from a standard house faucet in order to analyze changes following treatment with a water purification system. The developed strategy was also applied to identify the concentrations of the 9 selected organic compounds in the water samples. Ultimately, the in-bottle TFME-GC×GC-TOFMS method is straightforward and provides comparable performance to other methods for low-level analyses of organic pollutants in drinking water samples.