RENEE MONTAGNE, HOST:

Electronic-cigarettes are often billed as a safe way for smokers to kick the habit. But it's not just smokers who are getting their fix this way. According to the Centers for Disease Control and Prevention, one in five kids in middle school who've tried an e-cigarette say they've never actually smoked a real cigarette. Between 2011 and 2012, e-cigarettes doubled in popularity among kids in middle and high school students.

Youth Radio's Jenny Lei Bolario explores the appeal and possible dangers of smoking e-cigarettes, also known as vaping.

JENNY LEI BOLARIO, BYLINE: At a middle school in the San Francisco Bay Area, 8th grader, Viviana Turincio, noticed some kids smoking in class - or at least, that's what it looked like.

VIVIANA TURINCIO: I was in 8th period and we had a substitute and there was a group at the table and they were just like smoking on the vape pen and the teacher was right there - and the teacher didn't even notice.

BOLARIO: The kids were smoking an electronic cigarette, sometimes called a vape pen. It's a hand-held, battery-powered device that vaporizes a liquid, which is often infused with nicotine. You inhale the vapor through a mouthpiece, and exhale what looks like smoke, which can smell like candy.

TURINCIO: My favorite flavor is gummy bears because it tastes really good.

(LAUGHTER)

BOLARIO: Vapor liquids come in various flavors but teens prefer dessert-inspired ones - like gummy bear - which are more appealing than the nasty smell and taste of burning tobacco.

Marleny Samayoa, also in the 8th grade, has favorite vape flavors.

MARLENY SAMAYOA: I like cotton candy, cherry flavors, vanilla. That's pretty much all I like.

BOLARIO: Have you ever smoked a cigarette before? Have you tried to smoke a cigarette?

SAMAYOA: I have but I didn't like it. It has kind of a weird taste to it, like coffee without sugar.

BOLARIO: E-cigarettes are easier for kids to buy than regular cigarettes. There's no federal age limit for how old you have to be. But some states, including California, prohibit the sale to minors. So middle schoolers turn to sites like eBay, where independent sellers don't ask for your age.

SAMAYOA: So a lot of kids are getting them online and they're just introducing it to a lot of other kids and then it just keeps going from there.

BOLARIO: Marleny noticed the growing popularity of e-cigs on social media sites like Instagram. Hashtag Vapelife and the pictures of people vaping are endless.

SAMAYOA: I take pictures or do tricks, like the O's, blowing O's and blowing them like on flat surfaces and, yeah, making tornadoes.

BOLARIO: Swirling clouds of vapor are touching down in theaters, restaurants and malls, while health professionals are trying to catch up with this new fad.

DR. CATHY MCDONALD: Right now, we don't have as much information as we would like.

BOLARIO: That's Dr. Cathy McDonald. She runs a center for Tobacco Dependence, Treatment and Cessation for Alameda County in California.

MCDONALD: What we know is that in research studies, 10 minutes of smoking an e-cigarette for a person who has never smoked a cigarette does cause a noticeable increase in airway resistance in the lungs.

BOLARIO: Dr. McDonald worries about more people using nicotine. But compared to the old fashioned, combustible tobacco, she feels like e-cigarettes might be an upgrade.

MCDONALD: It's probably better than smoke, and I say that because smoking cigarette is 4,000 chemicals, 400 are poison, 40 cause cancer. I mean it's not great. However, you have to understand that we've been studying cigarettes for years and years and years, you know, so it's really difficult to know.

BOLARIO: Researchers haven't had the time to do long-term studies comparing traditional cigarettes to electronic ones. But at least among my friends, the ones who've made the switch have noticed positive change. My boyfriend, Gray Keuankaew, is one of them.

GRAY KEUANKAEW: Within the two months that I've been vaping, my body feels a little bit more healthy. I'm a runner so I'm able to kind of run a little bit longer without having to catch my breath. So if it's going to be any type of positive benefit, then I'm definitely going to a stick to it.

BOLARIO: I'm glad it's easier for him to run, but he hasn't outrun his nicotine addiction. With e-cigarettes they still have nicotine and you choose what amount you want. The Tobacco Vapor Electronic Cigarette Association estimates that e-cigarette sales will surpass $2.5 billion this year.

Geoff Braithwaite owns Tasty Vapor, a company in Oakland that sells and distributes liquids for e-cigarettes.

GEOFF BRAITHWAITER: Our target customer base is those people who felt doomed to a life of smoking. But there's going to be that novelty around it, it's a brand new thing, it's an electronic device. That kind of stuff is always going to appeal to kids. It would have appealed to me.

BOLARIO: Anti-smoking campaigns spent decades and billions of dollars to make smoking less appealing to youth. But cheap prices for brightly colored e-cigs, sweet flavors, and the ability to vape anywhere is putting nicotine back on the kids menu. The FDA has said it plans to regulate e-cigarettes, but so far the agency hasn't issued any rules.

For NPR News, I'm Jenny Lei Bolario.

MONTAGNE: And that story was produced by Youth Radio.