CHARACTERISTICS OF POLYCYCLIC AROMATIC HYDROCARBON FORMATION DURING SMOKING

Abstract

This study examines the concentrations of polycyclic aromatic hydrocarbons (PAHs) incigarettes and sidestream cigarette smoke. All 16 gas-phase PAHs and fourteen particulate-phase PAHs weredetermined in sidestream cigarette smoke for four brands of cigarettes. The median total of gas-phase andparticulate-phase PAH concentrations after two cigarettes were smoked were 79.6 ng/m3 and 10.0 ng/m3, andthe concentrations were several times higher than before smoking. Median PAH increases in the air sampleswere 1050 ng per cigarette for gas-phase PAHs and 228 ng per cigarette for particulate-phase PAHs. Gas–particle partition coefficients (Kp) of PAHs in air samples before and after smoking were correlated with thesubcooled liquid vapor pressures (PLo) of PAHs. The slopes of log-log plots of Kp versus PLo before and aftersmoking were -0.270 and -0.575, respectively. PAH partitioning between the gas and particle phases aftersmoking was closer to equilibrium state because the slope was closer to -1. Furthermore, all 16 PAHs weredetermined in the cigarettes. The medians of total PAH concentrations in the four brands of cigarettes were353 ng/g before smoking and 1130 ng/g after smoking. Median PAH increase in the cigarette samples duringsmoking was 1410 ng per cigarette. The relationships in the concentration of the between total suspendedparticulate (TSP) and total particulate-phase PAHs, and between total gas-phase PAHs and total particulate-phase PAHs were significantly positive. These findings imply that lowering the amount of TSP generated willlower the amounts of PAHs generated.