A critical review on the diverse preconcentration procedures on bag samples in the quantitation of volatile organic compounds from cigarette smoke and other combustion samples

It is challenging to analyze environmental tobacco smoking (ETS) samples given the diversity of hazardous toxic components and the difficulty of collecting/treating the samples. As one of the simple means to quantify volatile organic compounds (VOCs) in ETS samples, researchers have used such combinations as the bag sampling method and in-bag solid-phase microextraction for GC-MS analysis. In this review, we describe various factors involved in the application of paired sampling/preconcentration procedures for the analysis of VOCs, especially in ETS samples (and other combustion sources). The reliability of such paired procedures is also evaluated by considering several components, e.g., the factors controlling QA/QC, the associated sources of bias, and the effect of temporal stability (on bag sampling). Accordingly, it is recommended that several QA-related terms involved in such application (e.g., accuracy, robustness, high throughput, and quantitativeness) ought to be assessed properly and reported in a more objective manner.