Sigh... there are so many things here that I want to respond to... I'll do my best to go point by point.- Any time you see that something has "trace amounts" of anything, feel free to behave as if nothing was found. Scientifically speaking, when a substance is present in trace amounts, what that literally means is that they found it, but in such low levels that it does not have an effect. There are trace amounts of lithium, arsenic, and countless other chemicals in your tap water, but it is still perfectly drinkable. The mere presence of something is not enough for it to be dangerous; it has to be present in high enough amounts to have an effect. If it is present in negligible amounts, it is listed as trace.
(If anyone uses "trace amounts" of anything as an argument against e-cigarettes, they are grasping at straws to prove a point. Trace amounts of chemicals do nothing other than show where a substance may have come from, e.g. tobacco flavored liquid may have trace amounts of the same chemicals found in tobacco leaves.)
- Aroma and vapor are not the same thing. As for coffee, unless you are literally standing over the coffeepot and inhaling its steam, you are not breathing coffee vapor. Sorry, but you need to find a better comparison.
- Essential oils are not put in our e-liquid, food flavorings are. They are not the same at all and, again, do not compare.
- The sick chihuahua is one case, but we cannot make a broad generalization based on one case. That is bad science. Chances are the animal had a particular sensitivity to the vapor. This does not mean that all animals are sensitive to e-vapor.
- Ingestion and inhalation are not the same thing, and metabolism only applies to things ingested, not inhaled. When something is inhaled, only very small amounts are ingested (as the mouth is part of the airway) and thereby metabolized. In the case of cats and PG, far less PG is inhaled in secondhand vapor than would be ingested if it were an ingredient in the cat's food. Then, as I stated before, and even smaller amount from vapor will actually be ingested. This is essentially the same as the difference between swallowing a few apple seeds (which contain cyanide) and swallowing a gram of pure cyanide.
- Fish don't breathe air, they breathe water. Given the surface area of the tank water plus the amount of air coming into the tank through the pump, and adding in the fact that the vapor is dispersed into the air throughout the room, they would be exposed to far, far less vapor than an air breathing mammal sitting in the same room.
I believe I've covered everything.
