Burns surgeons are warning of the dangers of electronic cigarettes after treating a string of smokers injured by exploding devices.
The call is being echoed by fire chiefs and trading standards experts who are joining forces to highlight the dangers to consumers tempted to buy cheap or imported vaping kits.
Plastic surgeons at Morriston Hospital's Welsh Centre for Burns and Plastic Surgery in Swansea said they had treated five patients for burns after e-cigarette batteries exploded.
"Before this year we hadn't seen any injuries like this. Now we have had five which reflects the rising popularity of these e-cigarettes," said consultant plastic surgeon Dai Nguyen.
Three of the patients had their devices in their trouser pockets when they exploded.
They include a 25-year-old who was paintballing at the time and a factory worker who suffered thigh and groin injuries as well as burns to his hand when he tried to extinguish the flames.
Surgeons were so concerned they notified trading standards officers and also wrote a paper highlighting the cases and calling for tougher import regulations on e-cigarettes coming into the UK and more guidance for consumers.
"It's not just us, this is something that is starting to be highlighted nationwide. I think we are only seeing the tip of the iceberg," Dr Nguyen said.
"I suspect a lot of A&E departments may also be dealing with these incidents and we're just not aware of them."
The patients she has seen only suffered superficial burns and have made a good recovery, but she said some people have not been so lucky.
"I am aware of other cases which have required surgery and skin grafts," Dr Nguyen said.
"There have also been reports of e-cigarettes exploding in people's mouths which resulted in catastrophic injuries similar to those you would experience if you were shot in the face by a gun."
Swansea Council trading standards officer David Picken urged customers not to be tempted by cheap imports and to always take care when buying.
"These chargers have not been constructed to the correct safety standards and are often counterfeit," he said.
"Take additional care when buying online. Consider carefully if the cheapest is the best, particularly when the goods are coming directly to you from a business outside of the UK and EU."
He said customers need to makes sure the e-cigarette is labelled correctly, check if it has a visible CE mark and ask the shop for information confirming they come from a reputable source.
In the past year Mid and West Wales Fire and Rescue Service have been called out to six house fires caused by e-cigarettes, and they fear there have been dozens of smaller blazes that firefighters were not called to.
Deputy head of community safety Steven Davies said: "We would urge the public to always charge them on a non-flammable surface away from other flammable materials, not to charge them over long periods or leave them unattended when charging."