Marlboro maker Altria is planning to launch MarkTen e-cigarettes

More teens are using these products, even as scientists increasingly raise concerns about the effects of e-cigarettes' "secondhand vapor" on children.

According to Altria more than 90% of adult smokers are using e-cigarettes and about two-thirds have tried them, but only small number use e-cigarettes daily.

Altria controls roughly half of the $100 billion U.S. tobacco industry but is playing catch-up in the estimated $1 billion market for e-cigarettes, battery-powered devices that turn nicotine-laced liquid into vapor.

The popularity of e-cigarettes continue to grow, leading U.S. tobacco companies such as Altria Group Inc. the maker of Marlboro cigarettes are announcing plans to launch their own e-cigarettes as they start to pose a small but growing competitive threat to traditional smokes.

Electronic cigarettes with different flavored E liquid are seen on display at the Vapor Shark store in Miami, Florida.

Julia Boyle enjoys an electronic cigarette at the Vapor Shark store.

Flavored E liquid for e cigarettes are seen on display at the Vapor Shark store.