The study debunks the popular belief that e-cigarettes are merely a substitute for cigarettes among adolescents.
E-cigarettes, or electronic cigarettes, vaporise liquids that may or may not contain nicotine.
In 2011, about 1.5 per cent of high schoolers had vaped in the past 30 days, according to the US National Youth Tobacco Survey. Four years later, that number skyrocketed to 16 per cent.
A study of 5,490 high school juniors and seniors shows tobacco use among teens in Southern California is on the rise.
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A decade earlier - before e-cigarettes were sold in the US - 9 per cent of surveyed teens in this age group reported that they had smoked, said lead author Jessica Barrington-Trimis, from the University of Southern California (USC).
"If teenagers who vape are using e-cigarettes instead of cigarettes, we would have expected to see the decline in smoking rates continue through 2014," Barrington-Trimis said.
"But what we've seen is a downward trend in cigarette use from 1995 to 2004 but no further decrease in cigarette smoking rates in 2014," she said.
The study followed five groups of high schoolers who graduated in 1995, 1998, 2001, 2004 and 2014.
Researchers collected the history of tobacco use in an individually administered questionnaire.
"An important question in the rapidly evolving landscape of youth tobacco product use is whether e-cigarettes are replacing cigarettes," said Rob McConnell, professor at USC.
"However, use of e-cigarettes by youth who would not otherwise have smoked results in exposure to the hazards of inhaled vaporised liquids and flavourings in e-cigarettes and may result in exposure to nicotine that can damage the adolescent brain," said McConnell.
However, when cigarettes and e-cigarettes were combined, some 14 per cent of high school seniors in 2014 said they had smoked or vaped in the last 30 days.
"Because e-cigarettes are perceived as less harmful and less dangerous than combustible cigarettes, another concern is that teens may be introduced to nicotine use via e-cigarettes," Barrington-Trimis said.