What is propylene glycol? It is is a chemical found in personal care products that acts as a penetration enhancer that keeps products from melting in heat and/or freezing when it is cold. It is found in items such as shampoo, conditioner, soap, acne treatment, moisturizer, toothpaste, deodorant, nail polish, mascara; basically anything you could … Continue reading What Is Propylene Glycol And Why You Should Avoid It.