Sidestream smoke analysis with Single Photon Ionisation/Time-of-Flight Mass Spectrometry (SPI-TOFMS)
Recently several studies dealing with online analysis of mainstream tobacco smoke utilising photo ionisation mass spectrometry (PI-MS), namely single photon ionisation (SPI) and resonance-enhanced multi photon ionisation (REMPI) time-of-flight mass spectrometry (TOFMS) have been published revealing the puff resolved dynamics of cigarette smoking. In this matter standard cigarettes, as well as single tobacco grade cigarettes, were investigated. In this study the chemical composition of the gas-phase and particulate phase of sidestream smoke emissions of these cigarette types is characterised using a laser-based SPI-TOFMS instrument. Sidestream smoke is generated from various cigarette types (2R4F research cigarette; Burley, Oriental and Virginia single tobacco type cigarettes) smoked under ISO conditions on a Borgwaldt single port smoking machine and collected using a fishtail chimney device. Like in mainstream smoke the concentration profiles of various substances in sidestream smoke can be categorised into several groups, either depending on the occurrence of a mainstream puff or uninfluenced by the changes in the burning zone during puffing. In general, substances which are influenced by the puff show a decrease in concentration during the two second puff duration followed by an increase of approximately ten seconds. Changes in the chemical composition of the different emission stages were analysed utilising Principal Component Analysis (PCA) after variable reduction by the calculation of Fisher-Ratios. The same statistical approach was applied to distinguish the emissions of different single type cigarettes. The sidestream emissions occurring directly after a mainstream puff is drawn from the cigarette strongly resemble the composition of mainstream smoke. Additionally, like in mainstream smoke, the chemical composition of the sidestream smoke is strongly affected by the tobacco type.