Assessment of the total volatile organic compounds in indoor air during the use of a new heat-not-burn product
PMI is developing products that have the potential to present less risk of harm to smokers who switch to these products versus continued smoking. The tobacco heating system (THS) is one of these products based on a technology that heats the tobacco instead of burning it. To address public health concerns about possible presence of polluting substances during indoor use of THS, a portfolio of methods has been established and currently covers 23 compounds. One of the methods consists of the determination of total volatile organic compounds (TVOC) based on ISO 16000-6. Due to the intrinsic nature of the matrices under investigation (high variety of volatile target compounds present at relatively low concentrations), the implementation/adaptation and validation of such a method is challenging. Indeed, although the ISO 16000-6 standard details sampling and some instrumental parameters, several additional aspects were critical to limit contaminations and improve overall method robustness. Examples of method improvements include preparation and storage of sampling tubes, implementation of monitors and use of parallel detectors. In addition, several approaches for chromatographic signals integration, compounds identification and semi-quantification have been investigated.
The validated method was applied in the context of a study reflecting the real-life use of THS. The determination of TVOC values, expressed in toluene equivalents, was achieved for three matrices (background air with human presence, air combined with the environmental aerosol of THS and air combined with environmental tobacco smoke [ETS] of a Marlboro Gold cigarette) as well as the identification and semi-quantification of their major constituents. This study was conducted under controlled conditions and proved that the variety of volatile compounds released in indoor air and their respective measured concentrations were higher in ETS compared to environmental aerosol of THS. The TVOC patterns during use of THS and the background were similar.