The smoking of heat-not-burn (HNB) cigarette products and its effects on indoor air quality

In this research, the concentration levels of volatile organic compounds (VOCs) are monitored in a designated smoking booth using heat-not-burn (HNB) cigarettes (in reference to 1R6F cigarette) with controlled variables of number of cigarettes smoked (1, 3, and 6 cigarettes), booth ventilation (closed vs. open), and time after the release of cigarette smoke (T₀ = 0, T₁ = 5, T₂ = 10, and T₃ = 20 min)). The total VOC concentration (TVOC) released from an HNB cigarette is compared as a collective group (TV_all) and as three individual subgroups (TV_n: TV₁ for 14 standardized VOCs (G₁), TV₂ for 17 reference VOCs (G₂), and TV₃ for 10 carbonyl compounds (CCs: G₃). Comparative analysis of TVOC emission concentration levels is performed in closed/open booth conditions. Accordingly, TVOC concentrations from HNB (1347/416 ppbC) are about one order of magnitude lower than those from 1R6F (14834/3435 ppbC). Nonetheless, the predominant components in G₁/G₂/G₃ of HNB are clearly identified as isoprene (14.2 ppb), dodecane (16.8 ppb), and acetaldehyde (17.6 ppb), respectively. The VOC emission characteristics of HNB cigarettes are further evaluated against conventional cigarettes (i.e., 1R6F) and typical indoor cooking activities (data for the latter from a complementary experiment in this study). Overall, the results underscore the relative emission potential of different indoor sources, offering valuable insight into their comparative impact on indoor air quality.