The term 'Benzene Source' can be summarized by two crossword solutions: TAR (3 letters) and COALTAR (7 letters). TAR is a dark, viscous liquid that is produced by the destructive distillation of organic substances such as wood, coal, or peat. Coal TAR is a thick, black liquid that is a byproduct of the production of coke and coal gas from coal. It is composed of hundreds of different compounds, including benzene, and is used in a variety of industrial applications.