Smoke 'em if ya got 'em. E-cigarettes, Originally marketed as tool to help stop smoking, they are now being used in a more recreational fashion. Their use by adolescents and adults has doubled from 2010 to 2012. While they may not contain all the harmful goodies that tobacco kills you with, they do contain nicotine, and quite a lot of it. It is nicotine that causes acute toxicity in tobacco exposure, most often in kids.
Jennifer Lowry addressed this in her recent commentary in ClinTox. Vomiting is the most common symptom in nicotine poisoning, but in significant ingestions, tachycardia, agitation, and seizures occur early, progressing to bradycardia, dysrhythmias, lethargy, and paralysis a-la the nicotinic acetylcholine receptors (primarily in the autonomic nervous system). She states "While e-cigarettes are believed to be a safer form of 'smoking', this does not equate to safer forms of nicotine." The E-cigarette solutions have a mean nicotine concentrations of 8.5–22.2 mg/mL and are sold in 5 to 20 mL vials. Keep in mind that the estimated lethal dose for nicotine in humans is 1 mg/kg. Even if you math skills suck as much as mine, it's easy to see these vials can be deadly (AKA one 20ml vial may contain 444mg of nicotine?) Add the fact that they can be bought in 'yummy' flavours and you have a potential for significant toxicity.