How close are we to definitively identifying the respiratory health effects of e-cigarettes?

Introduction:
This text provides an overview of the potential respiratory health effects of e-cigarettes, drawing on evidence from various studies. It highlights the current understanding of the impact of e-cigarettes on lung health, as well as the limitations of the available data. The reader will learn about the chemical composition of e-cigarette aerosols, the potential harm caused by inhaling particulates, and the results of in vitro and animal studies on e-cigarette toxicity. The text also discusses the respiratory symptoms experienced by e-cigarette users and the potential risks of secondhand vaping.

Key Points:

* E-cigarettes contain far fewer potentially toxic chemicals compared to tobacco smoke, but concentrations of some metals may be higher.
* E-cigarette aerosols may expose users to smaller particulates and lower amounts of particulate matter compared to tobacco cigarettes.
* In vitro studies suggest that e-cigarette flavorings and nicotine could lead to lung cell damage and inflammation.
* Animal studies have shown that exposure to e-cigarettes can lead to increased airway hyperreactivity, distal airspace enlargement, and mucin production.
* Observational studies have reported mixed results on the respiratory effects of e-cigarette use, with some studies suggesting potential benefits and others indicating potential harms.
* There is a lack of epidemiologic studies on the respiratory effects of chronic e-cigarette use, particularly in adolescents and young adults.
* Exposure to secondhand e-cigarette aerosols may involuntarily expose nonusers to nicotine and particulates, but the respiratory effects of such exposure are not well understood.

Main Message:
The text highlights the need for further research on the respiratory health effects of e-cigarettes, particularly in the context of long-term use and secondhand exposure. While e-cigarettes may pose fewer respiratory health harms compared to tobacco cigarettes, they are not without risk. Healthcare providers and policymakers should be cautious in promoting e-cigarettes as a harm reduction strategy until more is known about their potential respiratory effects.

Ratajczak, Alexsandra, Wojciech Feleszko, Danielle M. Smith, and Maciej Goniewicz. “How Close Are We to Definitively Identifying the Respiratory Health Effects of E-Cigarettes?” Expert Review of Respiratory Medicine 12, no. 7 (July 3, 2018): 549–56. https://doi.org/10.1080/17476348.2018.1483724.