Undoubtedly, the greatest risk for high level exposure to benzene is in the workplace. Occupational exposure to benzene is likely to occur in the rubber industry, oil refineries, chemical plants, and the shoe manufacturing industry, as well as in gasoline storage, shipment, and retail stations. However, most individuals are exposed to benzene through tobacco smoke, automobile exhaust and other environmental sources such as gasoline filling stations, industrial emissions, and food products that contain benzene naturally. Indoor exposure can result from glues, paints, furniture wax, adhesives and detergents.
In addition, certain industries may release benzene into the surrounding air. These include ethyl benzene and styrene production facilities, petroleum refineries, chemical manufacturing plants, and recovery plants for coke oven byproducts. Leakage from underground storage tanks or from hazardous waste sites containing benzene can also result in the contamination of well water.