What Should You Know About E-cigarettes?

Electronic cigarettes, often called e-cigarettes, are battery-operated devices that provide inhaled doses of a vaporized solution of either propylene glycol or vegetable glycerin along with liquid nicotine. An atomizer heats the solution into a vapor that can be inhaled. The process, referred to as "vaping," creates a vapor cloud that resembles cigarette smoke. Some liquids contain flavoring, making them more appealing to users.

"As of right now, there is no long-term safety data showing the impact of repeated inhalation of propylene glycol or vegetable glycerin on lung tissue," cautions Jon Ebbert, M.D., associate director at Mayo Clinic's Nicotine Dependence Center. "There is some short-term data suggesting that e-cigarettes may cause airway irritation, but until we have long-term safety data, we are not recommending e-cigarettes for use among cigarette smokers to help people stop smoking."

So, what is known about electronic cigarettes?

*Manufacturers claim that electronic cigarettes are a safe alternative to conventional cigarettes.

*The Food and Drug Administration (FDA) has questioned the safety of these products.

*FDA analysis of two popular brands found variable amounts of nicotine and traces of toxic chemicals, including known cancer-causing substances (carcinogens).

*The FDA has issued a warning about potential health risks associated with electronic cigarettes, but is not yet regulating their use or standards of manufacture.

"It's an amazing thing to watch a new product like that just kind of appear. There's no quality control," says Richard Hurt, M.D., director of Mayo Clinic's Nicotine Dependence Center. "Many of them are manufactured in China under no control conditions, so the story is yet to be completely told."