Effects of electronic cigarettes and hookah (waterpipe) use on home air quality

Characteristics of second-hand exposure to aerosols from e-cigarettes: A literature review since 2010

In recent years, the use of electronic vaping products (also named e-cigarettes) has increased due to their appealing flavors and nicotine delivery without the combustion of tobacco. Although the hazardous substances emitted by e-cigarettes are largely found to be much lower than combustible cigarettes, second-hand exposure to e-cigarette aerosols is not completely benign for bystanders. This work reviewed and synthesized findings on the second-hand exposure of aerosols from e-cigarettes and compared the results with those of the combustible cigarettes. In this review, different results were integrated based upon sampling locations such as residences, vehicles, offices, public places, and experimental exposure chambers. In addition, the factors that influence the second-hand exposure levels were identified by objectively reviewing and integrating the impacts of combustible cigarettes and e-cigarettes on the environment. It is a challenge to compare the literature data directly to assess the effect of smoking/vaping on the indoor environment. The room volume, indoor air exchange rate, puffing duration, and puffing numbers should be considered, which are important factors in determining the degree of pollution. Therefore, it is necessary to calculate the "emission rate" to normalize the concentration of pollutants emitted under various experimental conditions and make the results comparable. This review aims to increase the awareness regarding the harmful effects of the second-hand exposure to aerosols coming from the use of cigarettes and e-cigarettes, identify knowledge gaps, and provide a scientific basis for future policy interventions with regard to the regulation of smoking and vaping.

Terms tobacco users employ to describe e-cigarette aerosol

BACKGROUND

The scientific term for the substance people inhale and exhale from a vaping device is 'aerosol', but whether the public uses this term is unclear. To inform tobacco control communication efforts, we sought to understand what tobacco users call e-cigarette aerosols.

METHODS

Participants were a national convenience sample of 1628 US adults who used e-cigarettes, cigarettes or both (dual users). In an online survey, conducted in spring 2021, participants described what 'people inhale and exhale when they vape', using an open-ended and then a closed-ended response scale. Participants then evaluated warning statements, randomly assigned to contain the term 'aerosol' or 'vapor' (eg, 'E-cigarette aerosol/vapor contains nicotine, which can lead to seizures').

RESULTS

In open-ended responses, tobacco users most commonly provided the terms 'vapor' (31%) and 'smoke' (23%) but rarely 'aerosol' (<1%). In closed-ended responses, the most commonly endorsed terms were again 'vapor' (57%) and 'smoke' (22%) but again infrequently 'aerosol' (2%). In closed-ended responses, use of the term 'vapor' was more common than other terms among people who were older; white; gay, lesbian or bisexual; college educated; or vape users only (all p<0.05). In the experiment, warnings using the terms 'aerosol' and 'vapor' were equally effective (all p>0.05).

CONCLUSIONS

The public rarely uses the term 'aerosol' to describe e-cigarette output, potentially complicating educational efforts that use the term. Future studies should explore public knowledge and understanding of the terms 'aerosol' and the more popular 'vapor' to better inform vaping risk communication.

PM1 exposure and spatial transmission of nicotine from the simulated second-hand vapor of pod-based electronic cigarettes

Electronic cigarettes (E-cigarettes) have gained significant popularity in recent years as a substitute for combustible cigarettes. However, there is growing concern regarding the safety of E-cigarette products for both the users and those exposed passively to second-hand emissions, which contain nicotine and other toxic substances. In particular, the characteristics of second-hand PM1 exposure and the transmission of nicotine from E-cigarettes remain unclear. In this study, the untrapped mainstream aerosols from the E-cigarette and smoke from cigarettes were exhausted by the smoking machines which were operated under standardized puffing regimes to simulate second-hand vapor or smoke exposure. The concentrations and components of PM1 released from cigarettes and E-cigarettes were compared under varying environmental conditions and regulated using a heating, ventilation, and air conditioning (HVAC) system. Additionally, the ambient nicotine concentrations and the size distribution of the generated aerosols were determined at different distances from the release source. Results showed that PM1 accounted for the highest proportion (98 %) of the released particulate matter (PM1, PM2.5, and PM10). The mass median aerodynamic diameter (MMAD) of cigarette smoke (0.5 ± 0.01 μm, geometric standard deviation (GSD) 1.97 ± 0.1) was smaller than that of E-cigarette aerosols (1.06 ± 0.14 μm, GSD 1.79 ± 0.19). The PM1 concentrations and chemical components were effectively reduced when the HVAC system was utilized. Nicotine concentrations in E-cigarette aerosols were comparable to those of combustible cigarette emissions when close to the exposure source (0 m), while they declined more rapidly than cigarette smoke emissions with increasing distance from the source. Furthermore, the maximum nicotine concentrations occurred in 1 μm and 0.5 μm particles in E-cigarette and cigarette emissions, respectively. These results provide a scientific basis for the assessment of E-cigarette and cigarette aerosol passive exposure risks, guiding the development of environmental and human health control measures for these products.

Fine Particulate Matter Exposure From Secondhand Cannabis Bong Smoking

This cohort study quantifies the levels of secondhand cannabis smoke from social bong smoking in a home environment.