What everyone needs to know about e-cigarettes

[quote__left]What are e-cigarettes (electronic cigarettes), and how do they work?
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E-cigarettes are products designed to deliver nicotine or other substances to a user as an aerosol. Using e-cigarettes simulates smoking cigarettes without burning tobacco. Typically, e-cigarettes are composed of a unit powered by a rechargeable battery, a replaceable cartridge containing liquid and an electronic atomizer that, when heated, converts the contents of the cartridge into an aerosol that the user can then inhale. The liquid contains four main ingredients: propylene glycol and/or glycerine as a base for producing the aerosol, flavours and optional nicotine.
About 500 e-cigarette brands are available today, but only a few have been analysed. A lack of knowledge about the contents of the inhaled mixture is linked to the problem of quality standards. Nevertheless, sufficient evidence shows that e-cigarettes’ aerosol is not just a water vapour, as the industry usually claims.
Variety in the levels of the toxicants and nicotine produced by e-cigarettes
The aerosol usually contains cancer-causing compounds (such as formaldehyde), but at levels 1–2 orders of magnitude lower than those in tobacco smoke. E-cigarettes are therefore likely to be less toxic than conventional cigarettes. Nevertheless, the levels of carcinogenic agents in some of the analysed brands are as high as those in the smoke produced by some cigarettes.
In addition, user behaviour – length of puffs, depth of inhalation and frequency of use – may affect nicotine absorption. Some users modify e-cigarettes at home to alter the delivery of nicotine and/or other drugs. Products vary widely in the ease with which they can be modified or filled with substances other than nicotine solutions.
Still have risks
These devices have become popular over the last 4–5 years. Little is known about the impact of e-cigarettes on health. As they contain fewer toxicants at lower levels than conventional cigarettes, e-cigarettes are likely to be less toxic. Nobody knows, however, how much less toxic they are.
Nevertheless, nicotine can affect brain development in foetuses and in adolescents, may contribute to cardiovascular diseases and may promote tumours, playing a role in malignant diseases. In addition, reports from both the United Kingdom and the United States of America indicate that the incidence of nicotine poisoning has risen significantly as the use of e-cigarettes has increased.
Further, there is evidence of health risks from the toxicants in e-cigarettes’ aerosol. While long-term effects, such as links to cancer and other diseases will not be known conclusively for some years, enough evidence indicates that these toxins are of concern for pregnant women who either use or are exposed to e-cigarettes.
WHO’s view on risks
According to WHO’s 2014 report, “Electronic nicotine delivery systems”, the main health risks from e-cigarette use come from the inhaling of nicotine and other toxic emissions from these products, either directly or second-hand.
Nicotine is the addictive component of tobacco. It can have adverse effects during pregnancy and may contribute to cardiovascular diseases. Although nicotine itself is not a carcinogen, it may function as a tumour promoter. Nicotine seems to be involved in fundamental aspects of the biology of malignant diseases, as well as of neurodegeneration. In addition, foetal and adolescent nicotine exposure can have long-term consequences for brain development. In addition to inhalation, the main health risk from nicotine exposure is overdose by ingestion or through skin contact. Users fill e-cigarettes’ containers themselves, so they, not the manufacturers, set the levels of nicotine. Nicotine poisoning can result from the liquid’s accidentally coming into contact with users’ skin or ingestion by children. The United States and the United Kingdom have already seen a tremendous increase in reported nicotine poisoning, often involving children.
Although e-cigarettes are likely to be less toxic than conventional cigarettes, they produce more than just water vapour. They contain some cancer-causing agents, such as formaldehyde, which in some brands reach concentrations close to those of some conventional cigarettes. E-cigarettes’ impact on health has not yet been determined.
At present, no governmental agency has yet evaluated and approved an e-cigarette product for smoking cessation, although the United Kingdom’s Medicines and Healthcare Products Regulatory Agency is reviewing some products.
Before considering e-cigarettes as a potential cessation aid, smokers should be encouraged to use a combination of already approved treatments. Nevertheless, experts suggest that appropriately regulated e-cigarettes may have a role to play in supporting some smokers who have failed cessation treatment, been intolerant to it or have refused to use conventional medication.
What products should I use to quit smoking?
For adults, WHO recommends licensed forms of nicotine replacement therapy (NRT): a therapeutic nicotine-delivery device produced under strict medical regulations for completely quitting smoking, with clear instructions on dosage, duration and methods of use. NRT (such as nicotine gum and the nicotine patch) delivers nicotine through skin or the lining of the mouth, and at lower levels and a much slower rate than smoking, which involves inhaling nicotine into the lung.
While the nicotine in e-cigarettes does not pose additional health risks for adult smokers, the evidence for the devices’ effectiveness as a method of quitting is limited and requires further research.
(Source WHO, edited.)