E-liquid, also known as smoke juice or e-juice, is a fundamental component of the electronic cigarette. While the tobacco in analogs is burned to create hazardous smoke, the e-liquid in an e-cigarette is heated by the atomizer to produce the vapor.
E-liquid contains a base (usually propylene glycol or vegetable glycerin), food flavorings and/or nicotine. Some e-liquid makers also use distilled water as an ingredient to dilute the fluid, but not all of them. Although a lot of people believe e-liquid contains only water, flavorings and nicotine, the truth is that without a base diluent, the vapor produced just wouldn’t fulfill its purpose. Propylene Glycol (PG) and Vegetable Glycerin (VG) are added for a number of reason:
- their increased viscosity keeps the nicotine molecules in suspension and produce thicker vapor, whereas water would simply evaporate upon exhalation;
- they dilute the mixture to correct nicotine strength and the intensity of the flavor;
- they enhance the throat hit – the sensation smokers get when the smoke hits the back of their throat.
PG, VG and nicotine have no discernible taste, so in order to make e-liquid more pleasant to vape, various flavorings are added. The number of flavor combinations are virtually limitless, from the most basic, like tobacco, menthol or chocolate, to exotic combinations of various fruits, or juices that replicate popular foods and drinks. All e-liquid manufacturers should use food-grade flavorings originally intended for human consumption.
Nicotine is a crucial ingredient of e-liquid, especially for smokers looking to quit tobacco cigarettes, and even for ex-smokers who still crave nicotine, in order to keep them back from relapsing to analogs. However, the vast majority of e-liquid makers also offer zero-nicotine varieties for vapers who have successfully beaten nicotine addiction. The most common e-liquid nicotine strengths are 0 mg/ml, 6 mg/ml, 12 mg/ml, 18 mg/ml and 24 mg/ml.
Until a couple of years ago, most e-liquid on the marked was sourced from China, which sparked quite a bit of controversy regarding safety and quality standards, but in recent years, more and more company have begun making their own e-liquid, adhering to FDA, FCC and USP standards.