Dynamic Chemistry of Passive Vaping Aerosols in the Indoor Environment

ALEXA CANCHOLA, Ying-Hsuan Lin, University of California, Riverside

     Abstract Number: 283
     Working Group: Health-Related Aerosols

Abstract
As e-cigarette usage continues to rise in popularity, passive vaping – inhalation of aerosols exhaled by an active user or contact with aerosols deposited on surfaces – remains a pressing public health concern. Research indicates that inhalation of e-cigarette exhalate may result in exposure to high concentrations of reactive carbonyl species, which may promote oxidative damage in biological systems. Furthermore, exhaled aerosols may linger in the air which increases the possibility of aging – especially in polluted regions with high levels of indoor oxidants such as ozone (O₃). This process may greatly affect the chemical properties of aerosols, potentially altering their toxicity upon exposure. While a great deal of research has focused on the characterization of active e-cigarette emissions, there is a gap in understanding of how interactions between e-cigarette aerosols and atmospheric oxidants may alter their physiochemical properties and the risk of oxidative damage upon exposure to non-users. To address this, we monitored the chemical composition and the presence of carbonyl-containing species in fresh and O₃-aged nicotine e-cigarette emissions using a combination of offline and online mass spectrometry approaches in a controlled environmental chamber. In addition, the real-time size distribution of the aging e-cigarette emissions were monitored using a scanning electrical mobility spectrometer (SEMS). We have found that when vaping emissions produced from disposable nicotine e-cigarettes are reacted with O₃, there is a clear shift in chemical composition, with increased production of carbonyl-containing species such as formaldehyde, acetaldehyde, pent-1-en-3-one, and methylglyoxal. The results of this study indicate that bystanders exposed to e-cigarette exhalate may be exposed to highly oxygenated compounds that may increase the risk of downstream respiratory diseases. Ultimately, our results provide important information that will help advance our understanding of the impact of e-cigarettes on indoor air quality.