Electronic Nicotine Delivery Devices (ENDD, also called electronic-cigarettes or e-cigarettes) are becoming popular, but their safety and efficacy as cigarette substitutes have not been adequately tested. Until these studies are conducted, their marketing poses health and safety concerns, particularly because the many products on the market are not regulated and no oversight of quality control is operated. At this time ENDD are not recommended as an aid to smoking cessation.

An Electronic Nicotine Delivery Device (ENDD) is a battery-powered device resembling a cigarette that contains a microcircuit activated when one draws on the mouthpiece, like taking a puff of a cigarette. With each puff a small amount of a solution (nicotine + humectant to produce vapour), contained in a cartridge, is heated and vapourised (depending on the brand, different flavours are available).

According to pharmacokinetic data from one study (Bullen et al., 2010), demonstrating a blood nicotine maximum concentration (Cmax) of 1.3 (95% CI 0.0-2.6) ng/ml at a time for Cmax (tmax) of 19.6 (95% CI 4.9-34.2) min, ENDD are basically oropharyngeal nicotine delivery devices, like the nicotine inhalator/inhaler used for nicotine replacement therapy. The systemic dose of nicotine obtained with ENDD is thus relatively small, but the amount of nicotine in the cartridge is substantial (from 0 mg, up to 16-18 mg), and could be a problem if a child ingested it, particularly because leakages from cartridges have been reported and seem not uncommon (Trtchounian & Talbot, 2011).

Small amounts of contaminants (e.g. TSNA) have been found in some products and might raise some health concerns, but these are present at much lower levels than in cigarette smoke. More of a concern could be the presence of medicinal drugs (e.g. rimonabant, or amino-tadalafil) (Etter et al., 2011).

No clinical trials have been reported yet, but some case reports, surveys and small studies seem to indicate that it may help smokers to quit smoking (Etter, 2010; Siegel et al., 2011; Trtchounian et al., 2010; Vansickel et al., 2010).

The main problem arising with these ENDD is that they are not regulated and that there is no oversight of quality control. There are already many ENDD products on the market (mostly through internet), and some could be more harmful than others. Standardisation of products (regulatory oversight) and clinical and non-clinical studies are needed before these products can be recommended for smoking cessation (Etter et al., 2011).

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Trtchounian A, Talbot P. Electronic nicotine delivery systems: is there a need for regulation? Tob Control. 2011; 20(1): 47-52.

Etter JF, Bullen C, Flouris AD, Laugesen M, Eissenberg T. Electronic nicotine delivery systems: a research agenda. Tob Control. 2011; 20(3): 243-248.

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Siegel MB, Tanwar KL, Wood KS. Electronic cigarettes as a smoking-cessation tool results from an online survey. Am J Prev Med. 2011; 40(4): 472-475.

Trtchounian A, Williams M, Talbot P. Conventional and electronic cigarettes (e-cigarettes) have different smoking characteristics. Nicotine Tob Res. 2010; 12(9): 905-912.

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