A Comparative Assessment of the FDA List of 93 HPHCs in Aerosol Generated by Tobacco Heating System 2.2 versus 3R4F Reference Cigarette Smoke

Abstract

The US Food and Drug Administration (FDA) published an inventory of harmful and potentially harmful constituents (HPHCs), which lists 93 chemicals (FDA 93) linked to the serious health effects of tobacco use. Some of the chemical compounds in the FDA 93 list were not characterized in earlier studies due to methodological limitations at that time. Leveraging new analytical methods, the current study quantitatively assessed an expanded list of 108 HPHCs in the tobacco heating system (THS) aerosol compared with smoke from the 3R4F reference cigarette. Analyses were conducted by Labstat International ULC, an independent laboratory accredited by the Standard Council of Canada to ISO/IEC 17025:2017, on two different THS HeatStick variants (regular and menthol) together with the THS version 2.2 and the 3R4F reference cigarette smoke using a Health Canada Intense smoking regime. Of the 108 HPHCs assessed in this study, 105 were either below the limits of quantification or showed substantial reductions in THS aerosol relative to cigarette smoke (all >45%), with no increased HPHC levels in the THS aerosol relative to cigarette smoke. Aside from nicotine, anabasine, and polonium-210 (210Po) which was near the limits of detection), the average reduction in the levels of HPHCs in the aerosol of THS compared with 3R4F reference cigarette smoke was >91.6% (Regular) and >92.2% (Menthol). The results for the two THS tobacco stick variants were remarkably similar. These results confirm that the elimination of combustion in THS results in a substantial reduction of HPHCs relative to cigarette smoke.