A new procedure is developed for the extraction of polycyclic aromatic hydrocarbons (PAHs) from the particulate phase of cigarette smoke. The procedure applies solid-phase extraction using a Bond Elut CH cartridge as a sample preparation step. The efficiency of the cleanup procedure is verified using a gas chromatographic (GC)-high-resolution mass spectrometric (MS) technique, proving that no interference occurs in the PAHs' determination. The efficient cleanup allows GC detection using either high- or low-resolution MS detection. Enhanced sensitivity is obtained using GC-MS and selected ion monitoring. This new technique has several advantages over other reported techniques. The method is simple and robust and has good repeatability and accuracy. The estimated detection limit is 0.1 ng/cigarette for benzo[a]pyrene. In addition to that, the recovery from the smoke pad in which the smoke is collected is approximately 97% for all PAHs. Results for the PAH analyses for 1R5F, 1R4F, and 1R3 Kentucky reference cigarettes are reported in this study. These results provide useful evidence for clarifying the controversy about previously reported data.

Fragmentation mechanisms of the methyl formate and methyl formate-d1 ions have been investigated using threshold photoelectron–photoion coincidence (TPEPICO) mass spectrometry. The breakdown diagrams and ion kinetic energies of fragment ions were measured at internal energies of the molecular ion from 0 to 7 eV, and fragmentation pathways were elucidated. The formation of HCO+ showed a large kinetic isotope effect. The formation of CH3O+ from methyl formate-d1 is accompanied by a large kinetic energy release, about twice that calculated using quasiequilibrium theory (QET). Its relative abundance in the breakdown curve also appears to be inconsistent with statistical theory. Direct dissociation from an isolated state of the molecular ion was one possible explanation. Slow dissociations were observed for the formation of methanol ions resulting from a migration of the formyl hydrogen while QET predicts no metastable dissociation for this process. Two-component reaction rates for methanol ion formation suggest participation of more than one state or isomer. The heat of formation of HCOO was found to be −40±6 kcal/mol, indicating that it is less stable than COOH (ΔHf =−58+4 kcal/mol).

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