Harsh Chemical is a term used to describe a type of chemical that is highly corrosive and can cause severe damage to living tissue. The most common example of this type of chemical is LYE, which is a strong alkaline substance composed of sodium hydroxide or potassium hydroxide. LYE is often used in the production of soaps, detergents, and other cleaning products. It is also used in the manufacturing of paper, textiles, and food processing.