Propylene glycol is a relatively thick, hygroscopic liquid that is virtually colorless and fully miscible with water and numerous organic solvents. Its low toxicity and high purity make it valuable component in cosmetics. It acts as a carrier fluid by dissolving a broad range of active ingredients, flavorings, and colorants that are otherwise insoluble in water. Acting as a penetration enhancer, it helps deliver active pharmaceutical ingredients (APIs) across the skin barrier. With a boiling point of 188 °C, propylene glycol is considered non-volatile and maintains stability over a wide temperature range.
Propylene glycol is widely used in personal care products, where it functions as a solvent, softening agent, and humectant. It is commonly found in fragrances, topical medications, soaps, facial creams, shampoos, foundations, body washes, and lotions. Keep in mind that “pharma-grade” doesn’t mean a product can be used for oral consumption. In the case of propylene glycol, it means the ingredient meets high purity standards and is safe for use in products that may come into contact with the body.
