Boy you sure are exposed to a lot of Propylene Glycol.
As the name suggests, it’s made from petrochemicals. It starts with natural gas or crude oil where propylene gas is created. Propylene oxide is then synthesized by making the gas react with chlorine or lye. Mix with water and you then get the alcohol needed to make propylene glycol.
It’s been around for a long time now, nearly 60 years in fact.
It mostly acts as a carriers of artificial flavor and colors in food and beyond food you’ll find it in shaving creams, shampoos and even some vaccines. Of all the worldwide production of the stuff, most of it is use industrially in things airplane deicer and laundry detergent.
It’s flavorless, colorless, less toxic than alcohol and once metabolized, it’s carried right out through your urine.