Examining Metal Contents in Primary and Secondhand aerosols Released by Electronic Cigarettes.

Introduction:
This article examines the metal contents in primary and secondhand aerosols generated by electronic cigarettes (ECs) from three different brands. The study aims to assess the mass of metals as a function of EC flavoring, nicotine concentration, device power, puff duration, and aging of the devices. The findings provide a more detailed understanding of the metal emission characteristics of ECs for assessing its health effects and policymaking.

Key Points:

* The masses of Cr, Cu, Mn, Ni, Cu, and Zn were consistently high across all brands in the primary and secondhand aerosols.
* The metals are predominantly released from the EC liquid, potentially through mechanisms such as bubble bursting or the vaporization of metal−organic compounds.
* high metal contents were also observed in simulated secondhand aerosols, generally 80−90% of those in primary aerosols.
* The metallic species in EC aerosols may have resulted from their working mechanism, which uses excessively heated metal filaments to vaporize the EC liquid.
* The transfer rate of metals from the filaments to the EC liquid depends on the airflow, nicotine concentration, EC liquid composition, and EC liquid temperature.
* The correlation between EC liquid ph and metals emitted was not observed, suggesting the possibility of other metal-transfer mechanisms.
* The leaching of metals into the EC liquid may even occur before vaping because of the acidity of some liquids.
* The smooth surface of the metal filaments showed drastic decay and fissures even within 150 puffs of usage.

Main Message:
The study found that the metallic species in EC aerosols may have resulted from their working mechanism, which uses excessively heated metal filaments to vaporize the EC liquid. The metals are predominantly released from the EC liquid, potentially through mechanisms such as bubble bursting or the vaporization of metal−organic compounds. high metal contents were also observed in simulated secondhand aerosols, generally 80−90% of those in primary aerosols. The findings provide a more detailed understanding of the metal emission characteristics of ECs for assessing its health effects and policymaking. The study suggests that the metal emission from ECs is a concern, and further research is needed to understand the health effects of metal exposure from EC use.

Kapiamba KF, hao W, adom S, Liu W, huang YW, Wang Y. Examining Metal Contents in Primary and Secondhand aerosols Released by Electronic Cigarettes. Chemical research in toxicology. 2022;35(6):954-962. doi:10.1021/acs.chemrestox.1c00411