By John Ostapkovich
PHILADELPHIA (CBS) -- Electronic cigarettes ("e-cigarettes") are marketed as safer than the regular variety, but many places with smoking bans are not taking any chances.
Instead of burning tobacco, an e-cigarette dispenses nicotine vapor, and proponents say what's exhaled is nothing but mist.
There's no standard formula for an e-cigarette. But one of the things found in them is propylene glycol. It's a substance not to be trifled with, according to Tracy Kane, tobacco dependence treatment specialist at Einstein Medical Center in Philadelphia.
"It's something you would find in antifreeze, and it is what's in e-cigarettes," she explains. "That's why I encourage people to use the FDA-approved nicotine replacement therapies instead of the e-cigarettes -- because we know what's in the FDA-approved ones."
Some places, including Einstein's main campus, ban e-cigarettes just as they do the regular ones.
Kane is not a fan of e-cigarettes but neither is she leading the charge to ban them in public.
"Most likely they're safer than regular cigarettes. We just don't know. So I'd like to see more research done with the e-cigarettes, so we know what it is, so before we give anybody advice to use them or not use them, let's find out what they really have in them and if they're safe or not."
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