PG and VG Explained
PG and VG Explained
The first time I saw PG and VG values on a bottle of ejuice, I had no idea what it meant. At first I thought it was a way of advertising that the particular harmful additive of the week was not present in this particular bottle. Then my imagination kicked in and I thought of it like movie classification ratings. PG stood for Pretty Grown-up and VG stood for Very Grown-up. But none of the labels of any ejuice anywhere had pictures of naked ladies with VG 100% clearly stamped, so the evidence was against my imagination
It turns out that PG stands for propylene glycol and VG stands for vegetable glycerin, the two liquids that make up the bulk of the liquid and provide the mechanism for vapor to be produced from warming a metal coil with a little bit of current from a battery.
Propylene Glycol is a clear, colorless liquid with a slightly sweet taste and a wonderfully intimidating chemical name. I was surprised to find out that as well as being used as a food additive, it is also used in the manufacture of polyester resins. It is an interesting twist of fate that I now love inhaling the stuff now, when in my younger days, I used to curse the styrene gas that curing polyester resin gave off in a fibreglass mold. The stuff used to boil my eyes out. Now I use one of those components to happily boil my tastebuds off.
And it is also used as a preservative for tobacco, ironically enough, since I used my vape to quit smoking in the first place. But unlike a tobacco leaf, the propylene glycol in ejuice is not combusted, and therefore, not causing the chemical stew of carcinogens that tobacco smoke deposits in our bloodstreams.
It is also used as the base liquid for asthma inhalers and it is rated as safe for food use. This begs the question of whether or not it is safe to inhale in aerosol form. Do people suffering from chronic asthma suffer any adverse affects from using their inhalers? Probably, but they have other issues and any problems caused directly or indirectly by inhaling Propylene Glycol are somewhat minor. Icing sugar is also rated as food safe, but it is not pleasant or safe to inhale. We need more and better controlled long term studies to be certain, but logic dictates two things. One is that it is nowhere near as damaging as tobacco smoke, and the other is that we haven’t been at this long enough to certain of anything else.
Vegetable Glycerin is roughly the same creature in its appearance and taste. It is not the same creature chemically. The most interesting thing about Vegetable Glycerin that I found was that it is a byproduct of producing biodiesel fuel. There is going to be a lot of it on the market soon, and ejuice prices may drop as it starts to get difficult to give the stuff away. It is classed as non toxic, but was never intended to be inhaled, which might change the classification some day, if we keep puffing on the stuff.
The two liquids are used in ejuice in a ratio. 70/30 VG to PG is the most common in fruit and dessert flavored juices. Some candy juices may go higher for sweeter flavors. You will see MAX VG on some brands and that total percentage can vary. It simply means that any more VG added to the mix changed the flavor too much and they are not willing to state the exact percentage, or might not even know.
Higher PG values are used in tobacco flavored juices. The Propylene Glycol provides what they call a “throat hit”. I have never liked the term but it will do as explaining it my way takes too much work. “Yeah, that must have been a high VG juice, I never felt it going down and I only tasted it when it went back out.” The throat hit is necessary for former tobacco smokers to feel as if they are actually smoking. A lot of the recreational vapers who never smoked a cigarette in their lives do not care for the throat hit and tend to prefer high VG juices.
The quality of the cloud is also affected by PG/VG ratios if that is important to you. PG produces less visible vapor and less mess on your coils, so you don’t have to replace them as often. VG feels much smoother, provides much more impressive clouds, but is more viscous and leaves much more residue on your coils.
Personal preference and equipment limitations really do dictate the correct choice for you. But there are plenty of choices for you to experiment with and enjoy.