Analysis of Selected Carbonyl Compounds in Tobacco Samples by Using Pentafluorobenzylhydroxylamine Derivatization and Gas Chromatography-Mass Spectrometry

A simple, accurate, and reliable method for routine analysis of trace carbonyl compounds, including formaldehyde, acetaldehyde, acetone, propionaldehyde, methyl-ethyl ketone (MEK), butyraldehyde, and crotonaldehyde, in processed tobacco products was developed. One gram of tobacco sample was spiked with a mixture of isotopelabeled carbonyls as internal standards and extracted with water. A portion of aqueous extract was derivatizated with o-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine hydrochloride (PFBHA). The PFBHA derivatives of carbonyls were extracted with hexane and analysed by gas chromatography- mass spectrometry (GC-MS). The accuracy and precision of the method were evaluated with spiked Kentucky Reference Cigarette 3R4F and CORESTA smokeless reference products CRP1, CRP2, CRP3, and CRP4. For the investigated carbonyl compounds, excellent recoveries (95-107%) and precisions (5-10%) were achieved with different spiked tobacco products, with the exception of acrolein, which was found unstable in all tested tobacco products. The linear range of the developed method was from 0.07 to 36 μg/g with limits of quantification ranged from 0.10 to 0.15 μg/g. Using this method, formaldehyde (0.31-6.24 μg/g) and acetaldehyde (0.84-17.7 μg/g) were detected in all tested reference tobacco products. Acetone (0.55-2.12 μg/g) was found in 3R4F, CRP1, CRP2, and CRP3. Detectable levels of propionaldehyde were only found in CRP1 and CRP3. The levels of MEK, butyraldehyde, and crotonaldehyde in all tested reference products were below the method quantification limits. It was found that the effects of storage conditions (storage time, container, and temperature) on yields of carbonyls detected in reference tobacco product samples (3R4F, CRP2, CRP3) were dependent on compound and sample matrix: the concentrations of formaldehyde in all tested reference products gradually increased as the storage time increased, while the concentrations of acetone in 3R4F samples dramatically decreased as the storage time increased. [Beitr. Tabakforsch. Int. 26 (2014) 86-97]