Respiratory Impact of Electronic Cigarettes and Low-Risk Tobacco

Abstract

Electronic cigarettes, handheld devices that generate an aerosol that may contain nicotine by heating a solution or e-liquid, have been increasingly used especially in the young population. The aerosol's composition is determined by temperature, and by the substances contained in the heated liquid: glycerin, propylene glycol, nicotine in variable concentrations, flavoring agents, and other non-nicotine compounds. >80 compounds (including known toxics, e.g., formaldehyde, acetaldehyde, metallic nanoparticles, and acrolein) have been found in e-liquid and aerosols. Airway irritation, mucus hypersecretion, and inflammatory response, including systemic changes, have been observed after the exposure to e-cigarettes, leading to an increase in respiratory symptoms and changes in respiratory function and the host defense mechanisms. E-cigarette has been linked with an increase of symptoms in individuals with asthma, cystic fibrosis, and chronic obstructive pulmonary disease. One of the major concerns in public health is the rise in e-cigarette experimentation among never-smokers, especially children and adolescents, which leads to nicotine addiction and increases the chances of becoming with time a conventional smoker. There is an urgent need to regulate e-cigarettes and electronic nicotine delivery systems, at least with the same restrictions to those applied to tobacco products, and not to consider them as harmless products.

A review of constituents identified in e-cigarette liquids and aerosols

“…EC exposure was associated with an increase in respiratory symptoms and changes in respiratory functioning and host defences, such as airway irritation, mucus hypersecretion, and inflammatory responses 46 . Several constituents listed in this review, such as diacetyl, acrolein, formaldehyde, and acetaldehyde, are known respiratory irritants 47 . E-liquids may be nephrotoxic, as they alter the antioxidant defences present in renal collecting ducts and promote minor changes in renal function 48 .…”

Cinnamon-flavored electronic cigarette liquids and aerosols induce oxidative stress in human osteoblast-like MG-63 cells

“…Several reports associate e-cigarette use with respiratory, gastrointestinal and cardiovascular complications including pulmonary damage [4], relapse of ulcerative colitis [5] and disrupted endothelial function [6]. While many studies focus on the respiratory and cardiovascular systems, the impact of e-cigarette use on the skeletal system is still unknown.…”

The Dark Side of the Force: When the Immune System Is the Fuel of Tumor Onset

“…Their users have high levels of neutrophil elastase, proteinase 3, azurocidin 1 and myeoloperoxidase, as well as other secondary neutrophil granule proteins in their sputum. All of these proteins are related to the innate defense role of leukocytes, bronchial inflammation and structural damage [69,70]. These results suggest that e-cigarettes, considered the safe alternative to tobacco cigarettes, can also induce lung inflammation and could therefore cause lung cancer.…”