Tokyo: E-cigarettes contain 10 times the level of cancer-causing agents as regular tobacco, Japanese scientists said Thursday, the latest blow to an invention once heralded as less harmful than smoking.
The electronic devices -- increasingly popular around the world, particularly among young people -- function by heating flavoured liquid, which often contains nicotine, into a vapour that is inhaled, much like traditional cigarettes but without the smoke.
Researchers commissioned by Japan's Health Ministry found carcinogens such as formaldehyde and acetaldehyde in vapour produced by several types of e-cigarette liquid, a health ministry official told AFP.
Formaldehyde -- a substance found in building materials and embalming fluids -- was present at much higher levels than carcinogens found in the smoke from regular cigarettes, the official said.
"In one brand of e-cigarette the team found more than 10 times the level of carcinogens contained in one regular cigarette," said researcher Naoki Kunugita, adding that the amount of formaldehyde detected varied through the course of analysis.
"Especially when the... Wire (which vaporises the liquid) gets overheated, higher amounts of those harmful substances seemed to be produced."
Kunugita and his team at the National Institute of Public Health submitted their report to the ministry today.
In common with many jurisdictions, Japan does not regulate non-nicotine e-cigarettes.
Nicotine e-cigarettes, or so-called Electronic Nicotine Delivery System (ENDS), are subjected to the country's pharmaceutical laws, but they can be bought easily on the Internet, although they are not readily available in shops as they are in some Western countries.
"You call them e-cigarettes, but they are products totally different from regular tobacco," the ministry official said.
"The government is now studying the possible risks associated with them, with view to looking at how they should be regulated."
In August, the World Health Organisation called on governments to ban the sale of e-cigarettes to minors, warning they pose a "serious threat" to unborn babies and young people.
Despite scant research on their effects, the WHO said there was enough evidence "to caution children and adolescents, pregnant women, and women of reproductive age" about e-cigarette use, due to the "potential for foetal and adolescent nicotine exposure (having) long-term consequences for brain development".