Wales could be the first part of the UK to ban smoking e-cigarettes in enclosed public spaces.
Welsh health minister Professor Mark Drakeford said officials were considering a ban amid concerns the products could "re-normalise" the use of conventional cigarettes.
He said there were also concerns that their spread could undermine the ban on tobacco smoking in enclosed public spaces, making it more difficult to enforce.
"We have spent 30 years ... creating a climate in this country where people understand that smoking is not something that is to be regarded as glamorous or desirable. We are concerned that e-cigarettes might reverse that tide," he told the BBC Radio 4 Today programme.
"We are concerned that they might act as a gateway to conventional cigarettes. It contains nicotine, it's highly addictive and you might then find it easier to move on to conventional cigarettes."
A recent study claimed e-cigarettes smoked by young people could lead to them picking up regular cigarettes.
The Health Equalities Group and the Centre for Public Health at Liverpool John Moores University suggests that claims by manufacturers that e-cigarettes prevent heavier smoking of tobacco are not necessarily true, with teenagers seeing them as different things.
The report's participants said e-cigarette use is becoming more common among young people who have never smoked traditional tobacco cigarettes, but the figures suggest the actual number is still very low. Around one in 40 e-cigarette smokers have never actually smoked tobacco.