Effect of Heating on Physicochemical Property of Aerosols during Vaping

Abstract

Many electronic cigarette manufacturers have offered different types of “high-end mods” that allow for controlled heating of the e-liquid. However, the controlled heating condition can drastically alter the inhaled aerosols’ physical properties and chemical substances, causing potential health risks. To investigate the contribution of heating on aerosol properties, we used four common power settings in the mods to conduct a physicochemical analysis. Our data showed that the aerosol mass and nicotine content in the aerosols increased at high power. Additionally, high power led to aerosolization of a viscous component in the e-liquid, increasing the viscosity of aerosol. However, the pH of the aerosol was constant regardless of the applied power. In addition, high-power operation made nicotine prone to oxidation, resulting in the color of the aerosol turning yellow. Lastly, we demonstrated that e-cigarette aerosol could contain various metals, including aluminum, arsenic, cadmium, chromium, copper, iron, magnesium, nickel, lead, and zinc. Even though these metal contents proportionally increased with the power setting, they remained far below the recommended exposure limits. Our finding demonstrates that the heating conditions of the e-cigarette change the physicochemical properties of the aerosols and their metal contents, thereby possibly affecting users’ oral and respiratory systems.

Characterization of an Electronic Nicotine Delivery System (ENDS) Aerosol Generation Platform to Determine Exposure Risks

“…Various studies have showed particle mass emissions that increased with higher power because of larger PG/VG mass consumption [ 25 , 47 , 54 , 55 ], which is consistent with the overall trend in this study that a 0.2 Ω coil emitted higher particles than a 0.6 Ω coil. However, for the same coil resistance, an increase in power seemed to have no effect or a decreasing trend on particle emissions.…”

Online quantification of nicotine in e-cigarette aerosols by vacuum ultraviolet photoionization mass spectrometry

“…The nicotine levels in e-cigarette aerosols are influenced by factors such as the nicotine concentration in the e-liquid, the PG/VG ratio, the power of the e-cigarette, the heating temperature, and puff topography. 36,37 In this study, only the nicotine concentration in the e-liquids was changed, leading to the observed result of the linear relationship. Additionally, the results obtained by SMPS and GC-FID demonstrate that the nicotine levels are the only variables changing within these aerosols, making them excellent calibration sources and expanding the calibration range easily.…”

The risk profile of electronic nicotine delivery systems, compared to traditional cigarettes, on oral disease: a review

“…According to recent research, the aerosolized e-liquid emitted from a heated ENDS may have physicochemical properties similar to those of high-sucrose gelatinous confectionery and acidic drinks. The viscosity of e-liquids combined with the chemicals in the flavorings may therein increase the risk of dental caries ( 53 ).…”