Doctors warn more smokers will die and suffer preventable diseases after the medicines regulator decided to maintain a ban on nicotine e-cigarettes.
The Therapeutic Goods Administration has rejected an application to exempt nicotine from the Schedule 7 dangerous poisons list, at concentrations of 3.6 per cent or less, in a bid to reduce the harm caused by tobacco.
In an interim decision on Thursday, the regulator said the ban would remain, arguing e-cigarettes could have a negative impact on tobacco control and may re-normalise smoking.
The decision has been labelled disappointing by e-cigarette campaigners who believe the devices provide a safer alternative to tobacco.
"There will be more potentially preventable deaths and diseases," Dr Alex Wodak, president of the Australian Drug Law Reform Foundation, told AAP.
"Surely any of us would want to see a heavy-smoking loved one switch from smoking to e-cigarettes and reduce their risk and maybe quit."
E-cigarette devices are legal in Australia but the sale and possession of the nicotine used in them is illegal.
Dozens of academics and researchers had written to the regulator in support of the application by the New Nicotine Alliance, calling for the ban to be lifted, including top Cancer Council researcher Ron Borland.
But opponents argued big tobacco would use the devices as another opportunity to get people hooked and normalise smoking again.
New Nicotine Alliance president Dr Attila Danko said the decision was a slap in the face to millions of Australian smokers who had struggled to quit.
"The TGA is essentially saying to the hundreds of thousands of Australians who have already quit smoking by using e-cigarettes: You quit the wrong way. We are not going to let you do this'."
"But you can go and buy a pack of smokes, no problem."
The TGA said the devices were associated with a risk of nicotine dependence, with evidence from the US showing it could encourage young people to take up smoking.
Dr Wodak accused the TGA of taking an ideological position on the devices at a time when Canada, New Zealand and the UK were moving toward them.
He believes the TGA should no longer be responsible for regulating what is a consumer product and wants smokers to be encouraged to use e-cigarettes instead.
"It's good to be open-minded and skeptical even about new developments - that's praiseworthy - but I don't think anyone could sensibly argue that e-cigarettes are anywhere near as risky as tobacco."
University of Sydney public health Professor Simon Chapman said the TGA's decision was commendable in light of recent evidence raising serious concerns about the dangers of nicotine.
He said Australia had achieved one of the lowest smoking rates in the world without e-cigarettes.
"The tobacco industry will unanimously condemn this decision - this is all anyone needs to know about why it should be welcomed," he said.
Liberal backbencher James Paterson told AAP parliament should act to legalise e-cigarettes.
"The TGA's decision today means the ball is firmly in the parliament's court," he said.
"Public health in Australia could be measurably improved if smokers were able to switch to e-cigarettes, as they are in many other similar countries."