E-liquid begins with the main base, vegetable glycerin. Most manufacturersuse certified organic VG—the glycerin doesn’t carry flavor very well, but does produce a lot of vapor. The next ingredient is propylene glycol—this is usually cited by alarmists as being a “main ingredient in antifreeze.” This is incorrect, as they’re willfully confusing it with diethylene glycol, which has actually been found in mass market e-cig products.
Propylene glycol—or PG—is a main ingredient in albuterol, or asthma inhalers, and is perfectly safe to inhale when vaporized. PG is thinner than VG, and carries flavor very well—the next ingredient, flavorings, are usually suspended in PG. Flavorings are food-grade, can be natural or artificial, and are limited only by the imagination of the juice maker.
A note about these ingredients—the “we don’t know what’s in these things” arguments dissolve in the face of numerous studies like these, showing that not only do we understand completely what’s in these things, but we also have a solid understanding of their (negligible) toxicity when vaporized.
The final ingredient is pharmaceutical-grade nicotine, and all juice manufacturers make their product available in varying nicotine strengths. They range from ridiculous (up to 36 milligrams per milliliter—basically a Lucky Strike with the filter ripped off) all the way down to nothing at all. That’s right, zero. So what’s the point of selling a “tobacco product” with no nicotine, you ask?