Tobacco smoke particulate matter chemistry by NMR

AbstractThe submicron liquid droplets constituting the particulate matter of mainstream tobacco smoke (PMMTS) are viscous and of a composition that is complex and poorly understood. PMMTS is often ∼80% w/w ‘tar’ where ‘tar’ = total PMMTS− (nicotine + water). Many of the chemical agents in MTS responsible for smoking‐related cancers are found at least partially in the PMMTS portion of MTS. The properties of PMMTS vary with brand and with puffing patterns. The chemical forms and total levels of nicotine, the identities/levels of other compositionally dominant compounds, and the identities/levels of carcinogens are of interest. Most studies of the composition of PMMTS have involved extraction then chromatography. Such methods allow the determination of low‐level constituents, but alter the samples such that direct information regarding chemical conditions within the PMMTS cannot be obtained. Here, we utilize nuclear magnetic resonance spectroscopy (NMR) to examine native PMMTS in conventional cigarettes, including measurements of the brand‐dependent fraction of PMMTS nicotine that is in the free‐base form (increasing this fraction in inhaled tobacco smoke affects the rates of the proc