Vaping is seen by many as a safe alternative to smoking tobacco, and many people use it as a way to wean themselves off cigarettes. This belief has been reflected in a newly-released government-commissioned report which promotes vapes as an effective “swap to stop” tool to help people quit smoking. The review, ordered by Health Secretary Sajid Javid, is attempting to kill off smoking entirely by banning new generations from buying cigarettes.
But how safe are e-cigarettes, and what does the evidence tell us about their potential health effects?
What are e-cigarettes and what is vaping? E-cigarettes are now a common sight.
There are two main types: an open system, where the liquid that is vapourised can be refilled manually, and a closed system which use ready-made refills that screw directly on to the e-cigarette's battery.
The devices work by heating up a liquid to create a vapour which is then inhaled by the user.
The liquid is commonly referred to as vapour and so the use of an e-cigarette is described as vaping. This vapour usually contains nicotine as well as other components, such as glycerol and flavourings.
There is a variety of styles on offer, from those that look like cigarettes, to vape pens, shaped like a pen or small tube, with a tank to store e-liquid, and "pod systems", compact rechargeable devices, often designed like a USB stick.
How dangerous are e-cigarettes? E-cigarettes usually contain nicotine and are not risk-free. “The liquid and vapour contain some potentially harmful chemicals also found in cigarette smoke” - though these chemicals are found at much lower levels in e-cigarettes, the NHS says.
The World Health Organization (WHO) says that there is growing evidence suggesting that smoking e-cigarettes could be associated with "lung injuries".
"In recent times e-cigarettes and vaping have been linked to an outbreak of lung injury in the USA," the WHO states on its website.
"E-cigarette emissions typically contain nicotine and other toxic substances that are harmful to both users, and non-users who are exposed to the aerosols second-hand."
The global health body has previously warned that e-cigarettes and vapes, which simulate the feeling of smoking, could act as a "gateway" to tobacco consumption.
The charity Action on Smoking and Health (ASH) found recently that 11.2% of 11 to 17-year-olds in Britain had tried vaping last year.
Even though it is illegal in the UK to sell nicotine products to anyone under 18, disposable vapes can be purchased online.
Experts have raised concerns that children are being sold cheap disposable vaping pens online that contain as much nicotine as up to dozens of cigarettes.
Doubts have also been voiced about the lack of data on the long-term risks associated with vaping.
Alizee Froguel, policy manager at Cancer Research UK, told ITV News: “Evidence to date shows that e-cigarettes are far less harmful than smoking tobacco and can help people to stop.
"But we strongly discourage those who have never smoked from using them, especially young people.
"This is because they are a relatively new product, and we don’t yet know their long term health effects."
Why do many experts say e-cigarettes are relatively harmless?
The NHS says vaping is significantly less harmful than smoking nicotine because they don't burn tobacco, and don't produce tar or carbon monoxide - two of the most damaging elements in tobacco smoke.
The regulation of e-cigarettes in the UK, which is far more rigorous than in the US, for example, was established when the UK was an EU member state, and so the UK's regulations are in line with other countries in the bloc.
British public health experts have largely welcomed vaping on the basis that e-cigarettes are about 95% safer than smoking. "At a rough estimate, it is expected to be under 5% of the risks of smoking if vaping continues over the long term," Prof Peter Hajek, Director of the Health and Lifestyle Research Unit at Queen Mary University of London, told ITV News. "Smokers who switch to vaping avoid almost all health risks associated with smoking. It makes sense to recommend such a switch, especially to smokers who find quitting difficult."
Health experts express their views on the safety of vaping
"For anyone who is a smoker, switching to vaping is likely to significantly reduce their risks of heart disease and lung disorders, not increase them," Deborah Arnott, Chief Executive of ASH, added.
Despite some potential harm from vaping, there is an established consensus that smoking traditional cigarettes is far more dangerous.
Almost six million people in England smoke, and tobacco remains the single biggest cause of preventable illness and death, according to the Department for Health and Social Care. One in four cancer deaths are thought to be linked to smoking. Cigarettes release over 5,000 different chemicals when they burn, many of which are poisonous, and up to 70 cause cancer.
Last year, it was announced that e-cigarettes could be prescribed on the NHS for the first time after the UK's medicines regulator updated its guidance for people who wish to give up smoking.
You can find more information about vaping on the NHS website here.
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