No abstract

Despite the growing popularity of new alternatives to traditional tobacco products, there is still limited evidence on their indoor effect in particular in residential spaces as specific environments where enforcement of air quality standards is difficult. Hence, the impact of the Tobacco Heating System 2.2 (THS, marketed as IQOS®) on indoor air quality was assessed under controlled experimental conditions using ventilation representative of residential buildings with natural ventilation. Smoking of cigarettes (Marlboro Gold®) at the same ventilation conditions and consumption rates was used as positive control. Before each THS 2.2 or Marlboro Gold session, a background session with the same volunteers as for the product-use session was held. In the high-load simulated residential environment, out of the 24 measured airborne constituents, only the increase of the indoor concentrations of nicotine, acetaldehyde, and glycerin above the background was attributable to the use of THS 2.2. The quantified concentrations of these three airborne compounds were significantly below the harmful levels defined in the air quality guidelines. Smoking Marlboro Gold resulted in much greater increases in the concentrations of all measured indoor air constituents, except for glycerin, and the indoor concentrations of several constituents exceeded the exposure levels set forth by cognizant authorities. Based on these data, it is reasonable to conclude that the use of THS 2.2 in environments where norms for indoor exposure in terms of adequate ventilation are respected does not adversely affect the overall indoor air quality.

Studies in environmentally controlled rooms have been used over the years to assess the impact of environmental tobacco smoke on indoor air quality. As new tobacco products are developed, it is important to determine their impact on air quality when used indoors. Before such an assessment can take place it is essential that the analytical methods used to assess indoor air quality are validated and shown to be fit for their intended purpose. Consequently, for this assessment, an environmentally controlled room was built and seven analytical methods, representing eighteen analytes, were validated. The validations were carried out with smoking machines using a matrix-based approach applying the accuracy profile procedure. The performances of the methods were compared for all three matrices under investigation: background air samples, the environmental aerosol of Tobacco Heating System THS 2.2, a heat-not-burn tobacco product developed by Philip Morris International, and the environmental tobacco smoke of a cigarette. The environmental aerosol generated by the THS 2.2 device did not have any appreciable impact on the performances of the methods. The comparison between the background and THS 2.2 environmental aerosol samples generated by smoking machines showed that only five compounds were higher when THS 2.2 was used in the environmentally controlled room. Regarding environmental tobacco smoke from cigarettes, the yields of all analytes were clearly above those obtained with the other two air sample types.

Despite the growing popularity of heated tobacco products, there are few comprehensive studies on their environmental aerosols. Therefore, the impact of the Tobacco Heating System 2.2 (THS 2.2) on indoor air quality was evaluated on the basis of a comprehensive list of 31 airborne constituents along with targeted screening of the gas–vapor and particulate phases of the environmental aerosol. The assessments were conducted at three ventilation rates. Indoor use of THS 2.2 increased the levels of nicotine, acetaldehyde, glycerin, and (if mentholated products were used) menthol relative to background levels, with a corresponding increase in total volatile organic compounds (TVOC) values. Moreover, a temporary increase in ultrafine particles was observed when two or more tobacco sticks were used simultaneously or with a short time lapse between usages, but the concentrations returned to close to background levels almost immediately. This is because THS 2.2 generates an aerosol of liquid droplets, which evaporate quickly. Nicotine, acetaldehyde, glycerin, and TVOC levels were measured in the low μg/m3 range and were below the existing guideline limits. A comparison of airborne constituent levels during indoor THS 2.2 use with emissions from combustion products and common everyday activities revealed a substantially lower impact of THS 2.2 on the indoor environment.