Electronic cigarettes imported from China have grown in the past many years and which has worried Fed regulators, in part, because so very little is understood about what’s in them. “Some products, which are sold as the same, have wildly variable amounts of nicotine in them,” Sharfstein says. “One of the products has a poison in it that’s diethylene glycol. And what that indicates is that we do not actually know much at all about the way these things are produced.”. Sharfstein claims e-cigarettes depend on FDA approval as a drug or medical device, very similar to nicotine patches, gum and inhalers and thus they are illegal till they’re cleared.