Electronic cigarettes
'E-cigarettes' are sold as a healthier alternative to real cigarettes as smokers can get their nicotine fix without inhaling tobacco, tar or carbon monoxide.
First developed in China, e-cigarettes look almost identical to real ones, but are made of stainless steel and run on batteries. Inside is a cartridge of liquid nicotine, which vaporises when heated so the user inhales droplets of the drug and breathes out a mist rather than smoke.
Initially the metal cigarettes were traded mainly online, but they are now appearing in high-street stores and market stalls, satisfying a demand from consumers trying to dodge the smoking ban.
Tests by UK trading standards officers revealed levels of nicotine in some products that were "highly toxic", the level that would normally need a warning label.
The World Health Organisation has raised concerns over a lack of research into the effects of the product.
