Component analysis of postnasal exhaled aerosols based on large volume thermal injection and in-column evaporative concentration technique

To characterize the composition of postnasal exhaled aerosols (PEAs) from smokers, an analytical method based on large-volume thermal injection followed by in-column evaporative concentration was developed. By using this novel PEA collection device under optimized parameters, the exhaled aerosol components by smokers using either Virginia type and US blended type cigarettes were analyzed and compared. In addition, a smoking machine was employed to replicate actual smoker's puffing profiles to quantify the releases of inhaled aerosol components which were then compared with those of the PEA components. The results showed that: 1) A total of 158 chemical components were detected in the PEAs, with relative standard deviations (RSDs) all below 15%, among which 100 were with RSDs below 10%; 2) For both Virginia type and blended type cigarettes, the releases of aerosol components from PEAs were significantly lower than those of retrohaling PEAs. The average retention rates across different chemical categories were not significantely different during inhalation, while significant differences were observed among cigarette categories during retrohaling. 3) Inter-individual variations in aerosol retention rates were relatively small during the smoking of both Virgina type and blended type cigarettes, while differences in retention rates due to smoking behaviors were more pronounced.