A hydrocarbon with chemical formula C6H6, benzene contains six carbon atoms in a ring structure.
A clear volatile liquid with a strong odor, it is one of the most extensively used hydrocarbons. It is an excellent solvent for fats, waxes, resins, oils, inks, paints, plastics, and rubber, and is a necessary intermediate in the production of many industrial chemicals, including gasoline. Benzene is used in the production of detergents, explosives, and pharmaceuticals. Benzene is found in emissions from coal and oil combustion, motor vehicle exhaust, and gasoline.
United States federal agencies classify benzene as a known human carcinogen based on studies that show an increased incidence of nonlymphocytic leukemia from occupational exposure and increased incidence of neoplasia in rats and mice exposed by inhalation and gavage (force-feeding). Because of these cancercausing properties, benzene has been listed as a hazardous air pollutant under Section 112 of the Clean Air Act (CAA) and has been replaced by the less toxic toluene (C6H5CH3) in some applications. Long-term exposure to benzene can result in the reduction of red blood cells, thus leading to anemia, excessive bleeding, and possibly affecting the immune system by altering levels of antibodies and white blood cells.
See also Explosives ; Leukemia .