The number of US youths who have tried e-cigarettes tripled from 2011 to 2013, raising concerns about the potential for a new generation of nicotine addicts, US health authorities said Monday.

More than a quarter of a million young people who had never smoked a cigarette used e-cigarettes in 2013, said the findings from the CDC.

That represents a threefold increase over the number that tried the electronic devices in 2011, it said in the journal Nicotine and Tobacco Research.

According to data from the National Youth Tobacco surveys of middle and high school students, 79,000 tried e-cigarettes in 2011, compared to more than 263,000 in 2013.