Metal concentrations in electronic cigarette aerosol: Effect of open-system and closed-system devices and power settings

Introduction:
This article presents a study on the metal concentrations found in the aerosol of different electronic cigarette (e-cigarette) devices and the effect of device power and type on metal emissions. The study also compares the metal concentrations to exposure limits and the doses received from reference tobacco cigarettes.

Key Points:

* The study analyzed 14 metals in the aerosol of four e-cigarette devices, two closed-system and two open-system, operated at different power settings.
* The open-system devices had higher metal concentrations than the closed-system devices, except for aluminum and uranium.
* The median concentrations of chromium and nickel, known components of coil alloys, were significantly higher in the open-system devices.
* The aerosol metal concentrations varied considerably within e-cigarette devices, with some elements ranging over several orders of magnitude.
* The study found that vaping practices, such as selecting device power, can affect metal concentrations in the aerosol.
* aerosol metal concentrations generally increased with power, but leveled off at higher power.
* The daily inhaled dose of typical e-cigarette users ranged from 0.02 to 0.13 µg/d for manganese and from 0.59 to 9.10 µg/d for nickel, with all samples from one open-system device and 88.9% of samples from another exceeding the MRL for nickel.
* The closed-system devices did not cause MRL exceedance for manganese and nickel, and the daily inhaled doses of these metals from these aerosols were lower than those from the mainstream smoke from the reference cigarette.

Main Message:
The study highlights the importance of considering device design, including coil composition and resistance, as well as device power in regulating e-cigarettes. The findings suggest that open-system devices may place users at increased health risks due to exposure to high levels of toxic metals as compared to closed-system devices. The study provides valuable information for legislators, policy makers, and healthcare providers to consider when addressing potential health risks associated with e-cigarette design and manufacturing.

Zhao, Di, ana Navas-acien, Vesna Ilievski, Vesna Slavkovich, Pablo Olmedo, Bernat adria-Mora, arce Domingo-Relloso, et al. “Metal Concentrations in Electronic Cigarette aerosol: Effect of Open-System and Closed-System Devices and Power Settings.” Environmental Research 174 (July 2019): 125–34. https://doi.org/10.1016/j.envres.2019.04.003.