Investigating E-Cigarette Particle Emissions and human airway Depositions under Various E-Cigarette-Use Conditions.

Introduction:
This text provides an in-depth analysis of a study investigating the impact of e-cigarette particle emissions and human airway depositions under various e-cigarette use conditions. The study examines the effects of e-cigarette device power, e-liquid composition, and vaping topography on e-cigarette particle sizes and their deposition in human airways. additionally, the study observes how measurement conditions, such as dilution ratio, temperature, and humidity, affect e-cigarette particle size measurements. The study's findings have important implications for understanding the potential health risks associated with e-cigarette use.

Key Points:

* The study used an e-cigarette device consisting of a cartomizer and a battery box, with a wide range of heating power output.
* Commercially available e-liquids were replaced with lab-prepared e-liquids to ensure quality control and understand the impact of e-liquid composition on particle formation.
* E-cigarette topography measurements were collected from 23 daily e-cigarette users, with e-cigarette device power output ranging from 5 to 59.7 W, an average nicotine content of 11.9 ± 10.0 mg/mL, and most users employing vegetable glycerin-based e-liquids.
* E-cigarette particles were generated under various conditions, including different device settings, e-liquid compositions, and vaping topographies.
* The size distributions and number concentrations of e-cigarette particles were measured using a portable aerosol mobility spectrometer and an optical particle counter.
* The study also evaluated the impact of dilution, temperature, and humidity on e-cigarette particle measurements.
* Deposition of e-cigarette particles in human airways was estimated using a modified multiple path particle dosimetry (MPPD) model.

Main Message:
The study highlights the importance of considering various e-cigarette use conditions and measurement conditions when assessing e-cigarette particle emissions and human airway depositions. The findings can help inform regulatory decisions regarding e-cigarette safety and contribute to a better understanding of the potential health risks associated with e-cigarette use.

Son Y, Mainelis G, Delnevo C, Wackowski Oa, Schwander S, Meng q. Investigating E-Cigarette Particle Emissions and human airway Depositions under Various E-Cigarette-Use Conditions. Chemical research in toxicology. 2020;33(2):343-352. doi:10.1021/acs.chemrestox.9b00243