E-cigarettes work by heating up a fluid that contains the drug nicotine, producing a vapor that users inhale. The devices are most popular among young adults, ages 18 to 24, a federal survey indicates. iStockphoto hide caption

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Vapor from an e-cigarette obscures the user's face in a London coffee bar. Dan Kitwood/Getty Images hide caption

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Shots - Health News

E-Cigarettes Can Churn Out High Levels Of Formaldehyde

Unexpectedly high levels of the cancer-causing chemical were found in an analysis of the vapor from e-cigarettes, researchers say.

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Jonathan Franzen, pictured here at The New Yorker Festival Fiction Night in 2009, won the National Book Award for his third novel, The Corrections. Joe Kohen/Getty Images hide caption

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A woman tries electronic cigarettes at a store in Miami. Joe Raedle/Getty Images hide caption

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