Vaping is the practice of inhaling an aerosol created by heating a liquid or wax containing substances, such as nicotine, cannabinoids such as tetrahydrocannabinol (THC), cannabidiol, additives, and flavorings such as propylene glycol, glycerol and flavored nicotine.

Vitamin E acetate is an oily chemical commonly added to THC vaping liquids to dilute or thicken them; the substance has been acknowledged as a potential toxin of concern by the Center for Disease Control and Prevention (CDC), due to its ability to remain in the lungs for long periods of time, and therefore cause complications in the lungs.