Dos and don’ts in the design of indoor air quality studies on smoke-free products


Indoor air quality (IAQ) studies on smoke-free products (SFP), such as heated tobacco products and e-cigarettes, have demonstrated substantial reduction of environmental emissions relative to cigarette smoking. IAQ studies on these products involve measurement of common airborne markers (volatile organic compounds, carbonyls, and particulate matter) together with specific tracers such as nicotine. Although indoor environments are typically free of such specific tracers, they naturally contain certain levels of the general markers, depending on human occupancy and activities. Accordingly, assessment of environmental aerosols of SFPs requires evaluation of confounding sources of pollution (e.g., study participants). Likewise, for studies in real-life environments, the impact of different daily life and recreational activities must be investigated. To assess the influence of these parameters on the concentrations of selected airborne constituents, we performed a study under simulated residential conditions in an environmentally controlled exposure room.