Teens are more likely to use electronic cigarettes if their friends and family view them as cool or acceptable, a new study suggests.
E-cigarettes, first introduced in China in 2004, are battery-powered devices that let users inhale nicotine-infused vapours.
"There is a lot of concern by the public health community that e-cigarettes may be recruiting a whole new group of people who never smoked cigarettes," said lead author Jessica Barrington-Trimis of the University of Southern California in Los Angeles.
Previous studies have found links between use of traditional and electronic cigarettes, Barrington-Trimis said. But the new study suggests some teens picking up e-cigarettes belong to a unique group.
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Many teens in the new study who said they'd recently used e-cigarettes had never smoked traditional cigarettes, the researchers found.
"If you think of e-cigarette and cigarette use as two circles, the overlap isn't as big as expected," Barrington-Trimis said.
Using data collected in 2014 from 2,084 Southern California teens, the authors found that about 25 percent reported ever using e-cigarettes and about 20 percent reported ever using traditional cigarettes.
About 10 percent had used an e-cigarette within the past 30 days, compared to about 6 percent reporting recent traditional cigarette use.
Teens were more likely to use e-cigarettes or traditional cigarettes if either product was used at home, if friends used either product or if peers viewed use of either product positively, the researchers reported in Pediatrics.
Fourteen percent of teens thought e-cigarettes are not harmful, compared to about 1 percent who thought cigarettes are not harmful.
The youngsters' understanding of possible harms from e-cigarettes or traditional cigarettes was tied to their likelihood of using either product.
Overall, the use of e-cigarettes and traditional cigarettes was linked, but about 41 percent of current e-cigarette users had never smoked traditional cigarettes.
The teens felt their peers were more likely to accept their e-cigarette use than traditional cigarette use.
The new study can't say e-cigarette use leads to use of traditional cigarettes, but the researchers suggest the new devices may lead to the "renormalisation" of tobacco products.
"Our findings really suggest there's a lot of kids who are using these e-cigarettes," Barrington-Trimis said.
The lack of research makes it difficult to know what to tell people about e-cigarettes, she added.
She said parents should tell their children that while research into the health effects of e-cigarettes is still in its infancy, nicotine is known to impact youngsters' developing brains.
Also, she said, little is known about the chemicals used to create the different flavors of e-cigarette vapors.
"Parents should just be aware if their teens are hanging out with other who are using these products," Barrington-Trimis said.
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