2. Relevance to Public Health 2.1 Background and Environmental Exposures to Styrene in the United States

Styrene is a high production chemical; the production capacity for styrene in the United States was over 12 billion pounds in 2008. Small amounts of styrene are naturally present in foods such as legumes, beef, clams, eggs, nectarines, and spices. It can also be present in packaged foods by migration from polystyrene food containers and packaging materials. Styrene is a combustion product of cigarette smoke and automobile exhaust. Manufactured styrene is primarily used in the production of polystyrene plastics and resins used principally for insulation or in the fabrication of fiberglass boats; production of copolymers such as styrene-acrylonitrile and acrylonitrile-butadiene-styrene, which are used to manufacture piping, automotive components, and plastic drinking glasses; production of styrenebutadiene rubber used to manufacture car tires, hoses for industrial purposes, and shoes; or formulated with unsaturated polyester resins used as fiberglass reinforcement materials. Styrene copolymers are also frequently used in liquid toner for photocopiers and printers.