Unfortunately, it appears my information on using e-cigarettes, or more correctly, personal vaporizers as a method of drug delivery was outdated. As it turns out, further study seems to indicate that any substance that can be dissolved in propylene glycol and absorbed through either the oral/nasal membranes and/or the lungs, AND that boils at the temps at which propylene glycol boils, can be vaped. Propylene glycol itself is harmless. It is used as the carrier vehicle in which nicotine and flavorings are delivered in e-cigs. In fact, it is also used in medicine as the delivery medium for many inhaled medications for asthma, etc. Vegetable glycerine, or VG, is also used in e-cigs, but is a lousy solvent and doesn't seem to be used for illicit drug delivery. Many of the drugs delivered via vaping are the "research chemicals" I mentioned in another posts. These chmicals, are, for the most part, made in China,and for the most part are strong opiods, euphorics, empathics (like molly or ecstacy) or psychedelics. Many of them can be delivered by vaping. The very good news is that China is in the process of cracking down on the producers of these drugs and as of now has banned 160 of them, with more to come. While this doesn't mean that the bathtub chemists won't be working feverishly to stay ahead of the bans, it should put a dent on what is available. That said, for the most part, if you find a personal vaporizer on your 15 year old, odds are still good that they are vaping nicotine. Research Chemicals are,for the most part, the province of slightly older drug users with a knowledge of chemistry, OR younger users with older contacts. The drug world is a LOT scarier than it was when I moved in that world in the 70s and all you had to worry about was getting a hit of bad acid, which was bad enough. What I don''t get at all is that many of us won't feed PET FOODS sourced with Chinese ingredients to our dogs and cats, yet there are people who will put Chinese-made psychoactive chemicals in their bodies?!?! I am continuing to research this subject. As always, questions are welcome for as long as my current level of obsessive fascination can hold out against my sense of absolute horror.