The controversial electronic cigarette, which has spread rapidly around the globe in its first six years, may help people quit cigarettes, a world-first study indicates.
Auckland University has reported the first substantial study of the device and found it is as good as a nicotine inhaler at reducing smoker's cravings - but nowhere near as good as a real cigarette.
One of the researchers, Dr Chris Bullen, said yesterday the study of 40 smokers showed the e-cigarette "might have potential" to be effective in helping smokers quit cigarettes, but more research was needed.
The findings are published in the British journal Tobacco Control, in which an editorial says e-cigs have "spread around the globe like wildfire" since the first model was marketed in 2004. They are banned in several countries.
The battery-powered e-cigarette looks like a cigarette and is mounted in a plastic mouthpiece. On inhalation it produces a vapour of propylene glycol solvent and nicotine - the addictive component in tobacco - but with a lower level of harmful chemicals than in tobacco smoke. Nicotine on its own is considered safe at the levels inhaled by smokers.
Some public health specialists want e-cigarettes made easily available as a quit-smoking aid alongside medicinal nicotine patches and gum. But others fear because the device mimics cigarette smoking, it is a path to tobacco addiction for teenagers and undermines attempts to portray tobacco as a dangerous, abnormal consumer product.
A New Zealand pharmacy is selling the device online for $140, plus $7 for nicotine cartridges equivalent to around 75 cigarettes - potentially in breach of the Medicines Act. People can import the cartridges for personal use but they cannot be sold in New Zealand.
Dr Bullen said e-cigarettes were sold at some New Zealand shops, but only with placebo cartridges that contained no nicotine.
He said before they could be recommended as a quit-smoking device, more studies on their effectiveness and safety were needed.
Christchurch public health specialist Dr Murray Laugesen commissioned testing of the same e-cigarette used in the university trial for more than 50 toxic chemicals found in cigarettes. None was found, except for a trace level of one.
He wants the Health Ministry to regulate nicotine e-cigarettes so they can go on sale by next year as a cheaper, safer alternative to tobacco for smokers.
But the ministry agreed more research was needed.
* E-cigarette reduced cravings as much as nicotine inhalers.
* Neither cut cravings as much as a real cigarettes.
* Cigarette produced 10-fold higher level of nicotine in blood than e-cigarette.
What is it
* E-cigarette looks like a cigarette in a mouthpiece.
* Produces mist of nicotine and propylene glycol solvent.
* Contains 100 times less toxic chemicals than cigarette smoke.