E-cigarettes: the burning question

Home Technologist 03 E-cigarettes: the burning question

They definitely help people stop smoking, but they may be just another ticking time bomb. Are they a positive solution or an unhealthy crutch?

Vapour from a cigarette

Every year, 700,000 people in the European Union die of tobacco-related illnesses. Some experts believe that electronic cigarettes could play a major role in fighting this scourge.

“It could eradicate smoking and thus greatly benefit public health,” says Peter Hajek, Professor of Clinical Psychology at the Queen Mary University of London. His review article, published last summer, covered more than 100 studies and emphasised the potential of e-cigarettes to reduce tobacco-induced morbidity and mortality.


Illustration of blue vapour from a cigaretteWhen an e-cigarette is activated, the battery (a) “lights” an atomiser (b) that vaporises an “e-liquid” (c) into aerosols that are then inhaled through a straw (d).

This liquid is made up of water, variable concentrations of tobacco-derived nicotine, propylene glycol (a food additive) or vegetable glycerine, along with flavourings and other additives – and sometimes, impurities.


Concentrations of toxic and carcinogenic substances in e-liquids are far lower than in regular cigarettes.

Nicotine is not toxic, except in pregnant women. It can contain impurities, particularly nitrosamines, carcinogenic compounds found in very small quantities.

Chronic exposure to propylene glycol can cause allergies and respiratory problems in vulnerable individuals.

Vegetable glycerine is in theory benign, but when heated it can produce a toxic substance. Some flavourings can be toxic or allergenic.


2003 Lik Hon invents the e-cigarette in Hong Kong.

2006 E-cigarettes are sold in Europe and the U.S. for the first time.

2013 The market reaches €2.3 billion, a tiny fraction of the global tobacco market, but enough to cut into sales of nicotine substitutes.

Electronic cigarettes deliver vaporised nicotine without burning tobacco, avoiding the production of carcinogens and other substances that harm the lungs and cardiovascular system (see Tobacco-free vapour, at right).

They deliver nicotine to the bloodstream more quickly than patches, and users can still employ the gestures that are part of their regular smoking habit.

“Vaping” e-cigarettes also helps people reduce their consumption of regular cigarettes. Nicotine-free e-cigarettes, however, are not popular.

Worried authorities

Despite these arguments in their favour, e-cigarettes remain a concern for public health authorities. They fear that e-cigarettes will lure non-smokers, thereby undoing the huge effort that has gone into anti-smoking campaigns.

“E-cigarettes renormalise the act of smoking by introducing a new tool that is particularly attractive to young people,” says Hubert Hautmann, a pulmonologist at the Klinikum Rechts der Isar Hospital of the Technische Universität München (TUM). “It’s important to note that the number of cigarettes smoked by young Europeans has been falling consistently since 1965.”

This concern seems unwarranted for the moment, since current studies indicate that e-cigarettes are used primarily by smokers. A study of 26,500 adults published by the University of Crete in June 2014 found that nine out of 10 Europeans who tried e-cigarettes in 2012 were ex-smokers or smokers, often heavy ones.

Many institutions nonetheless remain sceptical and concerned. In August 2014 the World Health Organisation (WHO) recommended banning the promotion of e-cigarettes to non-smokers and youth, as well as their use in workplaces and public areas.

Hajek disagrees with these recommendations. “This is likely to discourage or even prevent smokers from doing what is right for their health. No study has shown that young people go beyond experimentation and develop a habit of regularly vaping e-cigarettes.”

Prevention or cure

TUM’s Hautmann argues for caution. “The health effects of nanoparticles in the vapour are unknown. It took until the 1950s to establish incontrovertible proof of the link between lung cancer and tobacco. We may need 20 years to understand the danger of e-cigarettes.”

Indeed, e-cigarettes expose the body to compounds whose long-term health effects are still not understood (see Hidden dangers). “Even if they seem to provide a useful way of breaking the smoking habit, we still need to evaluate the effects of chronic exposure,” adds Maria Rosaria Gualano, a public-health scientist at the University of Turin.

There is also a small risk of second-hand vapour exposure. A 2014 University of Southern California study showed that although exhaled vapour contained 10 times fewer toxic substances than smoke, it contained more chromium and nickel particles (probably emitted from the cartridges). Establishing stricter manufacturing standards should reduce these uncertainties. “Some studies show that very low quantities of toxic substances are present in e-liquids,” says University of Geneva public health expert Jean-François Etter. “But in my estimation the e-cigarette reduces the risks of cigarettes by 99 per cent.”

Some public health experts worry that tobacco companies will take over the market and develop e-cigarettes that will hook users. “This risk must still be weighed against that of tobacco, which kills half of all smokers,” Hajek argues. Compared to the ravages caused by cigarette smoking, e-cigarettes seem like a lesser evil – at least from what science says in 2014.

LEGISLATION: A fragmented continent

Map showing European legislation on e-cigarettesEuropean countries are not all on the same page when it comes to e-cigarettes. Some treat them as regular consumer products, others as tobacco products subject to special taxes. Still others classify them as health products, such as nicotine replacements.

Since market authorisation is a complex and expensive process, big pharmaceutical and tobacco companies have a distinct advantage.

The revision of the European directive on tobacco products, which will go into effect in 2016, includes e-cigarettes that contain nicotine. It sets a maximum concentration of 20 mg/ml, requires a health warning and bans advertising. It gives individual countries discretion to determine age limits for consumption.

E-cigarettes containing higher nicotine concentrations must be included in the framework of products covered by health regulations.

Some experts deplore this tightening of regulations. “It only reinforces the market for cigarettes by raising obstacles to the development of e-cigarettes,” says University of Geneva expert Jean-François Etter. “The maximum concentration of nicotine is too low for really heavy smokers.”

Photo of Jean-François Etter

In 2013 Jean-François Etter, Professor of public health at the University of Geneva, published a book entitled
La vérité sur la cigarette électronique (“The Truth About E-cigarettes”).

“After a year, half the vapers stopped smoking”

Every tobacco alternative must be considered seriously, says expert Jean-François Etter.

TECHNOLOGIST How do you explain the success of e-cigarettes?

JEAN-FRANÇOIS ETTER Many smokers know about the risks associated with smoking. E-cigarettes are a very similar substitute and five times cheaper. And they deliver nicotine to the bloodstream faster than patches.

TECHNOLOGIST Is it an effective way to stop smoking?

JEAN-FRANÇOIS ETTER Yes, even if there is no definitive proof. Our data indicate that after 12 months half of the “vapers” stopped smoking regular cigarettes. Two random trials showed a small positive effect, but these were e-cigarettes with small nicotine concentrations.

TECHNOLOGIST Why do you consider e-cigarettes a “public health revolution”?

JEAN-FRANÇOIS ETTER Anything that is an alternative to tobacco smoking is beneficial. This is not just the case for e-cigarettes, but also similar devices that heat and vaporise tobacco without burning it, some of which will soon come on the market. The real problem with cigarettes comes from combustion, which produces several toxic and carcinogenic by-products. Nicotine itself is not dangerous. We can deplore nicotine addiction for moral reasons, but the fact remains that it’s a reality in our society.

TECHNOLOGIST What do you think of the tobacco industry’s entry into the e-cigarette market?

JEAN-FRANÇOIS ETTER For now, they’re selling less-powerful models, and only in the U.S. and UK. Eventually they’ll probably dominate the market, thanks to their experience with regulated environments. Not many people will be convinced that they’re true partners, though. They can’t do much to improve their image.

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