Hey John,
Our conversation has prompted me to do a bit of research, and I'll tell you my now quasi professional opinion. Like I said I have 2 or 3 E-cigs, and have used them off, and on. I actually like them better than a traditional cig. But, being a cigar guy they just don't have the steam, or the bouquet I crave from a big ol' stoggie. Like you said the craving for the real deal is very much psychological. I truly LOVE the flavor of a Partagas black label, or a Punch grand crue #2. If they ever develop the E-quivalent I would be E-lated. Their are a few offerings, but they miss the mark. The E-cig however does do a good job approximating a cigarette. The E-cigars are a bit nappy IMO.
So here's my quasi professional opinion now that I read a few articles pro, and con. The diluent used in the E-juice is as you said PG, VG, or PEG 400. The PG, or propylene glycol is what is used in medical inhalants anway, and is on the FDAs GRAS list. (Generally Regarded As Safe) The nicoteine being "harmless" is a bit of an over simplification. Water is poisonous at the correct dosage. It'll make your electrolytes shift, and squish your brain like a cantaloupe, but you'd have to drink A LOT, and fast.
Nicoteine does in fact boost mental focus, and stimulate the nervous system just like caffeine, just like most other compounds ending in "eine" or "aine." A certain amount is necessary, and without any at all your nerves would not fire at all. We like to boost that effect a bit with more than the amount naturally found in common foods. In moderation you are right no great risk is present with the nicoteine alone. It seems the carriers used in the E-cig is generally regarded as safe. The articles I found discouraging the use of E-cigs could only site the "We just don't know in the long run." argument, which is a weak one in my opinion.
However... dun dun duuunn. My original caveat about potential overdosing still stands. The highest legal concentratin of E-juice is 36 mg/ml. In the advertising they drop the "/ml", and just say 36mg. That is not 36mg for an entire bottle. That is 36 milligrams per milliliter. The largest standard bottle is 30ml. That would contain over 1 gram (1080ml) of nicoteine. Your dosage for lethality is correct at 40-60mg, but it isn't quite that simple either. It is dosage over time. 40mg over a 24 hour period is probably about what a chain smoker takes in. If that same 40mg hit the blood stream all at once, then yes, you are in big trouble. Now vaping, or smoking 30, or 40 mg over an hour or two would be wholly different than orally ingesting 30, or 40mg all at once. Nicoteine is toxic, and by that I mean the literal translation, it is readily absorbed through mucous membranes. The absorbtion rate would be different. So I guess not only is the poison in the dose the poison is also in the route of administration. Orally it would take about 150mg at once to harm you because of the second pass effect through the liver where the liver would process the majority of it before hitting circulation. So you can see that one 30ml bottle of high concentration E-juice has about 8-10 lethal doses of nicoteine if the entire contents were mistakenly ingested. The point being don't let kids or pets anywhere near it. I'm sure that goes without saying, and is just common sense, but I still think that the potential danger should be disclosed better. A bottle of E-juice misused is about 5 times more dangerous than rat poison. Rat poison is required to have a big Jolly Roger on the side, and say "poison." I don't think they should do this with E-juice, but it should have a bit more of a warning on the bottle than what mine has. It just says "Not for oral consumption" in small print on the bottom of the label. It needs to say "Harmful, or fatal if swallowed." Maybe some do, and mine's just lacking.
So used correctly, and with common sense moderation I think it is a much safer alternative. A sensible amount of nicoteine in PG vapor should be fairly safe. Plus there's my #1 rule of thumb. If it works for you then use it!
. If you like Obama, and his policies I appologize again, but please plug your brain in to charge. I
really feel sorry for the uninformed that these new "hopey changes" are going to kill.
