Supercritical fluid extraction and gas chromatography/mass spectrometry for the analysis of tobacco-specific nitrosamines in cigarettes.

A method for measuring four tobacco-specific nitrosamines (TSNAs), an important group of compounds in tobacco products, was developed. These compounds were extracted using supercritical fluid extraction (SFE) and purified by a sodium hydroxide wash of the ethyl acetate eluting solvent and solid-phase extraction. Quantitation was performed using gas chromatography/mass spectrometry (GC/MS). Spiking experiments were carried out to determine the recovery, precision, and limits of detection of this method. The detection limits were 0.04 microgram per sample for N'-nitrosonornicotine and N'-nitrosoanatabine and 0.02 microgram for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and N'-nitrosoanabasine. This method was used to measure TSNAs in various brands of cigarette tobacco with excellent reproducibility. The variation of TSNA levels among the cigarettes of different packs and types was significantly smaller than that among different brands. Comparable TSNA levels were obtained with SFE and liquid extraction methods. Signal-to-noise levels were similar for GC/MS and GC/thermal energy analysis when low-level tobacco samples were analyzed.