BACKGROUND. Electronic cigarettes (ECs) are electronic nicotine delivery systems (ENDS). ECs have been sold as a safer alternative to traditional cigarettes due to the lack of tobacco combustion since 2006. Their use has risen dramatically not only among current smokers willing to quit, but even among never-smokers and adolescents. Anyway, few data are available on the effects of ECs’ use on respiratory health. This article aims to summarize the available evidence on this matter.
MATERIALS AND METHODS. We collected on PubMed relevant studies and case reports on electronic cigarette use and its effects on respiratory health.
RESULTS. Electronic cigarettes’ structure includes several sources of toxicity. Its constituents are rich in heavy metals, founded in various concentrations in the aerosolized vapor. E-liquid used to refill EC’s cartridge is made of propylene glycol (PG) and vegetable glycerin (VG), which irritate the respiratory system. Moreover, e-liquid taste is often ameliorated with a wide range of commercial or homemade flavors, whose safety is uncertain. Several studies revealed that ECs vapor induces harmful effects at different levels of the respiratory tract, from airways to lung parenchyma, altering the pulmonary homeostasis. E-cigarette, or vaping, product use-associated lung injury’ (EVALI) is a pulmonary disease described for the first time in 2019, characterized by the presence of bilateral ground-glass opacities on chest imaging, affecting people with a history of ECs in the previous 90 days. Moreover, current literature suggests a potential carcinogenic role of ECs and describes vaping as a risk factor from asthma developing and exacerbations.
CONCLUSIONS. From available data, ECs should not be considered a harmless alternative to tobacco cigarettes.
There is an urgent need for further studies to establish the long-term effects of vaping.