New research claims that teenagers used to smoking e-cigarettes containing high levels of nicotine are likely to move onto smoking conventional cigarettes.

The Philadelphia Inquirer reports that Adam Leventhal, the director of the University of Southern California Health, Emotion and Addiction Laboratory at the Keck School of Medicine in Los Angeles, conducted a study showing a link between the use of e-cigarettes containing high levels of nicotine and the smoking of conventional cigarettes by teenagers.

“We know that teens who vape e-cigarettes are much more likely to become conventional cigarette smokers,” said Leventhal. “Our study suggests that the nicotine in e-cigarettes may be a key reason why teens who vape progress to more frequent smoking.

Leventhal and his team studied 181 grade-10 students from high schools around Los Angeles who stated that they had used an e-cigarette in the past month and provided Leventhal with the nicotine levels in the e-cigarettes.

Leventhal and his team then contacted the same students six months after the initial research, discovering that the students using e-cigarettes with higher levels of nicotine were more likely to have used e-cigarettes as well as conventional cigarettes in the past month. Approximately 43 percent who had used the higher level nicotine e-cigarettes classified themselves as “frequent smokers” of conventional cigarettes.

In comparison, only ten percent of those that smoked lower-level nicotine e-cigarettes had begun smoking conventional cigarettes on a regular basis.

“While previous research reported that most adolescents were using nicotine-free e-cigarettes, results from our survey and other soon-to-be-published studies show that many more teens are vaping e-cigarettes with nicotine than we originally thought,” Leventhal said in a university news release.

Lucas Nolan is a reporter for Breitbart News covering issues of free speech and online censorship. Follow him on Twitter @LucasNolan_ or email him at lnolan@breitbart.com