Electronic cigarettes—A review of the physiological health effects

Abstract

Electronic cigarettes (ECs) are devices that are used recreationally or as smoking cessation tools, and have become increasingly popular in recent years. We conducted a review of the available literature to determine the health effects caused by the use of these devices. A heating element in the EC aerosolizes a solution of propylene glycol, glycerol, nicotine (optional), and flavouring (optional). These compounds are generally harmless on their own. However, upon heating, they produce various carcinogens and irritants. We found that concentrations of these toxicants vary significantly depending on the type of EC device, the type of EC liquid, and the smoking behaviour of the user. Exposure to these vapours can cause inflammation and oxidative damage to in vitro and in vivo cells. EC aerosol can also potentially affect organ systems and especially cardiovascular and lung function. We concluded that EC use causes acute effects on health but not as severe as those of conventional cigarettes (CCs). These devices could, therefore, be of use for smokers of CCs wishing to quit. However, as EC aerosol introduces new toxicants not found in CCs, long-term studies are needed to investigate possible chronic effects associated with EC use.

Metal/Metalloid Levels in Electronic Cigarette Liquids, Aerosols, and Human Biosamples: A Systematic Review

“…Reviews on e-cigarettes have summarized e-cigarette development (Cooke et al 2015;Glasser et al 2017), their impact on decreasing smoking use (Kalkhoran and Glantz 2016;Rahman et al 2015), health and physiological effects Pisinger and Døssing 2014;Zucchet et al 2017), and effects of vaping on indoor air quality (Fernández et al 2015;Zainol Abidin et al 2017). Some of these reviews reported on metal levels; in addition, two systematic reviews have specifically evaluated metals/metalloids in cig-a-like cartomizers (Mishra et al 2017) and in e-cigarette aerosols (Gaur and Agnihotri 2019).…”

Prevalence, knowledge and attitude toward electronic cigarette use among male health colleges students in Saudi Arabia—A cross-sectional study

“…Regarding the prevalence of ECs users among our students with reference to each college separately, medical students represented the highest (47.4%), followed by dental, pharmacy and nursing participants −40.7, 34.5, and 32%, respectively. This increase in the user rate among medical students is higher than locally and globally reported rates from Al-Faisal University and Qassim University in Saudi Arabia (12.2 and 10.6%, respectively) ( 18 , 19 ) and University of Minnesota (15.3%) ( 36 ). Similarly, the proportion of ECs users among pharmacy students was higher compared to those at Midwestern University in the United States, 34.5 vs. 14%, respectively ( 37 ).…”

“…For example, only 35.44% of the participants knew that ECs were not considered smoking cessation products and only 45.65% agreed that ECs had adverse effects. In addition, 36.03% stated that ECs produce vaporized nicotine only, which contradicts the reality that they contain potentially carcinogenic and non-carcinogenic toxins beside nicotine ( 36 ). It is worth mentioning that smoke from ECs contains far fewer carcinogenic particles than conventional cigarettes smoke ( 37 ).…”