At North Carolina smoke shops and other retailers, the warning signs are going up.
A law banning the sale of e-cigarettes to minors takes effect Thursday.
Retailers now face the same misdemeanor charge if they sell e-cigarettes to a minor as they already did for other tobacco products. Penalties can be as high as a $1,000 fine.
So retailers say they'll be careful.
E-cigarettes are battery-powered devices that heat a liquid nicotine solution, creating vapor that users inhale. Some are made to look like a real cigarette with a tiny light on the tip that glows.
Devotees tout them as a way to break addiction to real cigarettes.
But public health officials say the safety of e-cigarettes and their effectiveness in helping people quit regular smokes haven't been fully studied.