Non-targeted analytical comparison of a heated tobacco product aerosol against mainstream cigarette smoke: does heating tobacco produce an inherently different set of aerosol constituents?

Abstract

Smoking-related diseases remain a significant public health concern, and heated tobacco products (HTPs) have emerged as a potential alternative to cigarettes. While several studies have confirmed that HTP aerosols contain lower levels of harmful and potentially harmful constituents (HPHCs) than cigarette smoke, less is known about constituents that are intrinsically higher in HTP aerosols. This study provides a comprehensive comparative assessment of an HTP aerosol produced with Tobacco Heating System 2.2 (THS) and comparator cigarette (CC) smoke aiming at identifying all unique or increased compounds in THS aerosol by applying a broad set of LC–MS and GC × GC–MS methods. To focus on differences due to heating versus burning tobacco, confounding factors were minimized by using the same tobacco in both test items and not adding flavorants. Of all analytical features, only 3.5%—corresponding to 31 distinctive compounds—were significantly more abundant in THS aerosol than in CC smoke. A notable subset of these compounds was identified as reaction products of glycerol. The only compound unique to THS aerosol was traced back to its presence in a non-tobacco material in the test item and not a direct product of heating tobacco. Our results demonstrate that heating a glycerol-containing tobacco substrate to the temperatures applied in THS does not introduce new compounds in the resulting aerosol compared to CC smoke which are detectable with the method portfolio applied in this study. Overall, this study contributes to a better understanding of the chemical composition of HTP aerosols and their potential impact on human health. Graphical Abstract

Applying new approach methodologies to assess next-generation tobacco and nicotine products

“…HTPs utilize a specifically designed tobacco rod for use in a corresponding device that consists of a heating element, a battery, and a microprocessor controller. For HTPs to yield emissions with drastically reduced levels of harmful and potentially harmful constituents (HPHCs) as compared to cigarette smoke, the heating element should only reach temperatures below those leading to combustion of the tobacco rod ( Baker, 1981 ; Malt et al, 2021 ; Lang et al, 2023 ; Sussman et al, 2023 ). The chemical composition of the resulting aerosol is typically significantly simpler than traditional cigarette smoke, with on average 90%–95% reductions in HPHC levels ( Schaller et al, 2016 ; Forster et al, 2018 ).…”

Pitfalls in the Detection of Volatiles Associated with Heated Tobacco and e-Vapor Products When Using PTR-TOF-MS

“…A comprehensive characterization of a heated tobacco product was performed to identify any additional constituents beyond the standard harmful and potentially harmful constituents. 9,10 There has also been extensive investigation into certain flavors in the liquids used in e-vapor products. 11 These studies offer the possibility of searching for potential new compounds of toxicological concern and identifying possible chemical tracers for heated tobacco and e-vapor products.…”

“…Use of alternative nicotine-delivery systems (e.g., heated tobacco products/heat-not-burn and e-vapor products/e-cigarettes) has increased in recent years. , Given the relative novelty of these products, it is important to determine if they contain compounds not found in cigarette smoke. A comprehensive characterization of a heated tobacco product was performed to identify any additional constituents beyond the standard harmful and potentially harmful constituents. , There has also been extensive investigation into certain flavors in the liquids used in e-vapor products . These studies offer the possibility of searching for potential new compounds of toxicological concern and identifying possible chemical tracers for heated tobacco and e-vapor products.…”