Wow! Great question. The law is lagging behind the technology here. The laws relating to minors and smoking currently read "tobacco and/or cigarette(s)." According to the Texas Tax Code, a tobacco product includes "an article or product that is made of tobacco
or a tobacco substitute and that is not a cigarette." If e-cigs are a tobacco substitute (and I'm guessing some enterprising prosecutor will argue that they are), then they are covered by the same laws as a regular cigarette.
Although it's not a legal issue, please consider this - the active ingredient in those e-cigs is the same as the active ingredient in real cigarettes. Nicotine. It is just as addictive and just as poisonous as the real thing. If you are a minor, please consider whether you want to knowingly inhale a poison. If you're considering giving an e-cig to a minor, please consider whether it is wise to provide a minor with a poisonous, addictive substance.
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