Transcript for Teen Use of Electronic Cigarettes on Rise
We also have a new headline tonight from the cdc about those electronic cigarettes, e cigarettes they are called. More people are using them, among teens users have doubled. Hollywood stars are inviting them to enjoy the vapor filled with nicotine. Reporter: The first new tv ad from big tobacco in 40 years. Hits the air waves in colorado this month. The product made by r.J. R reynolds that promise the pleasures of smoking without lighting up. Actress katherine heigl recently sold david letterman on the allure. This is remarkable. Reporter: Celebrity smokers have become walking ads for these gadgets which came on the market a few years ago and are now hugely popular. 500 million worth sold last year according to industry estimates, double that this year. People who do it call it vaping, not smoking. They insist it's not secondhand smoke. It's just water vapor. Is it safe? Yes. You hope so. Reporter: The trouble is, no one knows. In the u.S. E cigarettes are completely unregulated. You have no idea what you are actually lighting up. One brand which was tested by the fda a couple of years back showed that it contained antifreeze which is poison. Reporter: No one can say for sure that the vapor is safe. We don't know whether using electronic cigarettes over the long term may predispose you to pneumonia. We just don't know. That's what is dangerous. Reporter: Because they're unregulated people can quietly vap in places where smoking is banned. Ex smokers swear by it saying it's helping them quit. It's helping me to stop. Reporter: It's got to be better than smoking or so they hope. David wright, abc news, los angeles.
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