What is PG?
PG or propylene glycol is an organic compound (a diol alcohol), usually a faintly sweet, odorless, and colorless clear viscous liquid that is hygroscopic and miscible with water and acetone. Propylene glycol is recognized as generally safe for human consumption by the Food and Drug Administration. It is used in food coloring, and flavoring, as an additive to keep food, medicines and cosmetics moist, and in machines that simulate smoke. Propylene glycol functions to provide the vapor mist that looks like smoke and to suspend flavor.
