Propylene glycol is often commonly referred to as propane-1,2-diol and it is a synthetic organic compound that contains a chemical formula of C3H8O2. In terms of the appearance of this product, it is a colorless liquid and also possesses very little odor. It does have a fairly sweet taste to it however. As it currently stands, nearly 45% of the propylene glycol that is produced is to be used as chemical feedstock in producing polyester resins. Fortunately, this chemical is going to have very little reaction when it comes into contact with humans in a variety of ways. The toxicity when consumed orally is very low and will only cause problems if it is consumed in large quantities. Additionally, if it comes into contact with your skin or your eyes or you inhale it, it will essentially pose very little risk, especially when it comes to the skin.