Electronic nicotine delivery systems (ENDS): A convenient means of smoking?

Electronic nicotine delivery systems (ENDS), which are becoming increasingly popular in many parts of the world, have recently become more sophisticated in terms of their more active content and better controlled vaporisation. This review begins by describing how cigarette smoking led to the development of ENDS as a means of combatting nicotine addiction. ENDS are usually categorised as belonging to one of only three main generations, but a fourth has been added in order to differentiate the latest, most powerful, most advanced and innovative that have improved heating efficiency. Descriptions of the principal substances contained in ENDS are followed by considerations concerning the risk of toxicity due to the presence of albeit low concentrations of such a variety of compounds inhaled over a long time, and the increasingly widespread use of ENDS as a means of smoking illicit drugs. We also review the most widely used pharmacotherapeutic approaches to smoking cessation, and recent epidemiological data showing that ENDS can help some people to stop smoking. However, in order to ensure their appropriate regulation, there is a need for higher-quality evidence concerning the health effects and safety of ENDS, and their effectiveness in discouraging tobacco smoking.