The effects of e-cigarette aerosol components on the morphology and function of the conducting portion of the respiratory system: a narrative literature review

Paweł Szumilas, Kamila Szumilas, Aleksandra Wilk, Alicja Zawiślak, Beata Karakiewicz


As electronic cigarettes (e-cigarettes, vaping, etc.) are considered a safer alternative to traditional smoking, they are gaining popularity, especially among adolescents (10–14 and 14–18 years) and young adults (18–25 years). They are used by millions of users worldwide, and new generations of e-cigarette devices are being introduced. Some reports have suggested that e-cigarettes have harmful effects on human health, which is why it is important to introduce restrictions on the use of e-cigarettes by young people. The aerosols produced when the e-liquid is heated contain a complex of gases, toxic substances and various types of flavoring chemicals, which are then inhaled by users. In addition, when the products in the e-liquid are thermally degraded, more harmful reactive substances are produced. Exposure to e-cigarette aerosols appears to have harmful effects on human health, but it is critical that our understanding of these effects be expanded and that data be collected on the long-term effects of the substances in e-cigarette aerosols on the human body. Data on the various health risks associated with the use of e-cigarettes are mainly based on in vitro studies using established cell lines or cultured human cells, or on animal models. The substances contained in e-cigarette liquids and their aerosol – including the solvents propylene glycol and vegetable glycerin – are known to cause organ and tissue irritation in the upper respiratory tract when inhaled. The aim of this narrative review is to present our current knowledge on the effects of the chemical components of e-cigarette aerosols on the nasal cavity, trachea, bronchi, and organs of the conducting part of the respiratory system.


e-cigarettes; e-aerosol; chemical components; ciliated columnar pseudostratified epithelium

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