Are electronic cigarettes safe to use?
Compared with smoking regular tobacco cigarettes, using an electronic cigarette is safer. However, in the absence of a thorough clinical evaluation and long term population level surveillance, absolute safety of such products cannot be guaranteed. By comparison, the harm from tobacco smoking is well established.
Toxins have been found in a number of studies of electronic cigarettes, although these are at levels much lower than those found in cigarettes and not at levels which would generally cause concern.
One small study showed that after switching from tobacco to electronic cigarettes nicotine exposure was unchanged while exposure to selected toxicants was substantially reduced. Most of the safety concerns regarding electronic cigarettes relate to the absence of appropriate product regulation and inconsistencies in quality control. The current lack of regulatory oversight means that there is significant variability in device effectiveness, nicotine delivery and cartridge nicotine content, both between and sometimes within product brands.
Research has identified possible concerns about specific products. A recent study by the US Food and Drug Administration (FDA) has raised some safety concerns over the presence of toxins, released in low concentrations, from the vaporisation process of certain cartridges. There is little evidence of harmful effects in the short to medium term from repeated exposure to propylene glycol, the chemical in which nicotine is suspended. One study concludes that electronic cigarettes have a low toxicity profile, are well tolerated, and are associated with only mild adverse effects. More research is needed on long-term impact, particularly on the lungs.