A highly volatile and water-soluble benzene derivative that is highly toxic to most forms of life. Its estimated lifespan in air is 60 hours in the case of a photochemical reaction with hydroxyl radical and is eventually oxidized to carbon dioxide. Toluene is used in a variety of industries including the manufacture of TNT, pharmaceuticals, rubbers, and other benzene derivatives, and is also a fuel additive and a paint solvent. Toluene also reaches the atmosphere from natural sources such as coal tar, mineral oils, and forest fires.
Source: Atmospheric Chemistry Glossary