Toluene, also known as methylbenzene, is a clear, colorless liquid with a distinctive sweet smell that is widely used in industrial settings as a solvent. Toluene also is an ingredient in some consumer products such as paints, glues and nail polish removers.
Toluene occurs naturally in crude oil and in the tolu tree. It also is produced when manufacturing gasoline and other fuels from crude oil and in making coke, a type of fuel derived from coal that is used to make steel.