Update – 21st August 2015
Public Health England has recently published an evidence review about e-cigarettes. The main finding of the review is that e-cigarettes are 95% safer than cigarettes and are an effective quitting aid.
Electronic cigarettes are to be licensed and regulated as an aid to quit smoking from 2016, it has been announced.
A dual approach to regulation for e-cigarettes- battery-operated devices that mimic cigarettes – will be introduced in May 2016.
E-cigarettes brands that make medicinal claims, such as “Helps you to quit smoking”, will require authorisation under existing medicines legislation, for which the Medicines and Healthcare Products Regulatory Authority (MHRA) is responsible. And only these types of e-cigarettes would be made available on prescription as a quitting aid, in the same way as nicotine replacement therapy (NRT) patches or gum.
E-cigarette brands that do not make such a claim will not require a medical license but they will have to meet a set of standards for safety and quality, as set out in the revised EU Tobacco Products Directive (TPD).
There will also be a set standard for packaging information so consumers can make an informed choice.
Regulations prohibiting the sale of electronic cigarettes to under 18s, or adults purchasing them on their behalf, will come into force on 1 October 2015 in England and Wales. Scotland and Northern Ireland are seeking to bring forward similar legislation within their respective parliaments.
Are e-cigarettes safe?
We don’t really know until they have been thoroughly assessed and monitored in a large population over time. However, compared with regular cigarettes, they are certainly the lesser of two evils.
A recent Public Health England evidence review concluded that e-cigarettes were 95% safer than "traditional" cigarettes.
First, e-cigarettes don’t contain any tobacco – only nicotine, which is highly addictive but much less dangerous. For this reason, smoking e-cigarettes (known as "vaping") is generally regarded a safer alternative to smoking for those unable or unwilling to stop using nicotine.
Also, while the US Food and Drug Administration (FDA) found the liquid and vapour to contain traces of toxins (PDF, 237kb), including cancer-causing chemicals nitrosamines and formaldehyde, the level of these toxins is about one thousandth of that in cigarette smoke.
We cannot be certain that these traces of toxins are harmless, but tests on animals and a small study of 40 smokers are reassuring, providing some evidence that e-cigarettes are well tolerated and only associated with mild adverse effects (slight mouth or throat irritation, a dry cough).
Public health charity Action on Smoking and Health (ASH) is cautiously optimistic, concluding in its January 2013 briefing (PDF, 447kb) that "there is little evidence of harmful effects from repeated exposure to propylene glycol, the chemical in which nicotine is suspended".
Others are more wary. Some health professionals do not recommend them because they believe the potential for harm is significant. It is worth bearing in mind that nicotine is not altogether harmless – for example, it has been linked to anxiety – and research suggests nicotine plays a direct role in the development of blood vessel disease.
E-cigarettes are banned by other countries and by some UK schools concerned about their influence on adolescents (see What are the other concerns?).
What do e-cigarettes contain, and how do they work?
Most e-cigarettes contain a battery, an atomiser and a replaceable cartridge. The cartridge contains nicotine in a solution of either propylene glycol or glycerine and water, and sometimes also flavourings.
When you suck on the device, a sensor detects the air flow and starts a process to heat the liquid inside the cartridge, so it evaporates to form water vapour. Inhaling this vapour delivers a hit of nicotine straight to your lungs.
Will they help me quit smoking?
We don’t yet know. The evidence so far is promising, but not strong enough to draw any firm conclusions.
A 2011 study and a 2013 survey found that e-cigarettes decreased the number of cigarettes consumed by smokers, and the survey also suggested they reduce cigarette cravings – although participants were recruited from websites of e-cigarette manufacturers, so results may not be representative.
It’s not certain whether e-cigarettes deliver as much nicotine as forms of nicotine replacement therapy such as patches, so they may not be as effective at curbing nicotine cravings.
However, they do have the advantage of looking and feeling like cigarettes: they satisfy the same hand-to-mouth action, give out a smoke-like vapour, and some even have an LED light that resembles the burning tip of a cigarette. This could be why a 2010 study found that even placebo e-cigarettes (with no nicotine) relieved the desire to smoke within the first 10 minutes of use.
If you want to try a safer alternative to cigarettes but are concerned about the uncertainties surrounding e-cigarettes, you may wish to consider a nicotine inhalator. This licensed quit smoking aid, available on the NHS, consists of just a mouthpiece and a plastic cartridge. It’s proven to be safe, but the nicotine vapour only reaches the mouth rather than the lungs, so you don’t get the quick hit of nicotine that comes with e-cigarettes (see box below, which compares e-cigarettes with inhalators).
E-cigarettes vs nicotine inhalators
Is there any risk to others from e-cigarette vapour?
It’s not clear until more studies are done (see Are e-cigarettes safe?). Research to date has not shown the vapour to be harmful – it largely consists of water.
According to ASH: “Any health risks of secondhand exposure to propylene glycol vapour are likely to be limited to irritation of the throat.” To support this, it cites a 1947 study that exposed animals to propylene glycol for 12-18 months at doses 50 to 700 times the level the animal could absorb through inhalation. Compared to animals living in a normal room atmosphere, no irritation was found, and the kidney, liver, spleen and bone marrow were all found to be normal.
What are the other concerns?
Because e-cigarettes can be smoked in public places such as bars, restaurants and public transport, some people feel they may be normalising what has come to be seen as an unacceptable activity.
Also, some argue that e-cigarettes (with their flavourings and clever marketing) are a "gateway to smoking" for children and teenagers, encouraging them to smoke when they wouldn’t otherwise take up the habit.
If they're not a gateway to smoking, they are at least a gateway to nicotine addiction. Cancer Research UK asks whether smokers who may have otherwise successfully conquered their nicotine addiction may be more likely to stay on e-cigarettes (and thus be addicted to nicotine) long term, if they start using them.
However, these are just theories and questions, which need to be properly researched before we can jump to any conclusions, and their potential influence on children will hopefully not be an issue when e-cigarettes are tightly regulated as a medicine.
Where do I buy e-cigarettes, and how much do they cost?
E-cigarettes are widely available online and from newsagents, supermarkets and even some pharmacies. They are currently not available on the NHS.
A single disposable e-cigarette costs about £6. A starter kit costs anything from £17 to £90 (many retail at around £35-£45). For this, you typically get a battery, a charger and two or more replaceable cartridges containing nicotine. When the cartridges run out, a four-pack of refills will cost you £10-£17. In all, they are estimated to be 20% cheaper than cigarettes (this may be an underestimate).
How long do they last?
E-cigarette manufacturers say that a refill cartridge is equivalent to anything from seven to 25 regular cigarettes, depending on its nicotine content – but these may be overestimates, and its duration obviously depends on how heavily you use the device. The battery is said to last between two and five hours.
This page was last updated on August 27 2015.
Edited by NHS Choices