Propylene Glycol is a synthetic compound extracted from petroleum refining widely used as a humectant or conditioning agent in skincare like moisturizers and lotions. However, it is considered to be a harmful ingredient and proven to be an irritant. There are cases where contamination of diethylene glycol, a toxic ingredient, were found in inadequate sources of this humectant. The contamination may lead to serious allergies on the skin and eyes, and exposure to the bloodstream can even cause brain damage and affect body functions. Despite that, in normal skin conditions small dosages have not yet provoked any significant effects. Although, we better be safe than sorry, especially for those with really sensitive skin.