Washington: E-cigarettes may be as addictive as traditional ones as they contain nicotine in the most addictive form, researchers say.
Electronic cigarettes or "e-cigs" have been touted as a tool smokers can use to wean themselves off of traditional cigarettes, which many believe are more harmful than their "e" counterparts.
But because e-cig liquid also contains nicotine and emits carcinogens, researchers wonder whether that perception is really true.
Researchers from the American University of Beirut in Lebanon and Virginia Commonwealth University in US found that much of the nicotine in e-cigarettes is the addictive form of the compound.
Although e-cigs don't burn tobacco, they heat and vaporise a liquid that contains nicotine, flavourings and other substances.
Some experts say the nicotine content could lead users to become addicted to e-cigs, or that it could even serve as a gateway to conventional cigarettes and other drugs.
But not all nicotine is created equal, and studies had yet to investigate what kind of nicotine was in the liquids.
Out of three forms, scientists believe "free-base" nicotine is the only one that gets absorbed by the body, making it the most addictive kind.
Researcher Najat Saliba and colleagues wanted to find out which nicotine forms are in e-cigs.
The researchers tested commercial samples of liquids made for the devices and found that, by and large, the nicotine was in the most addictive form.
They also determined that the concentration of nicotine varied and often didn't match the concentrations the labels claimed.
The study was published in the American Chemical Society (ACS)'s journal Chemical Research in Toxicology.