Hexane is used to extract edible oils from seeds and vegetables, as a special-use solvent, and as a cleaning agent. Normal hexane (n-hexane) is both an anthropogenic and naturally occurring chemical. n-Hexane is a minor constituent of crude oil and natural gas. For practical and economic reasons, hexane is the dominate extraction solvent for oil seeds, used throughout the world. However, hexane is an irritant to the skin and can be absorbed through the skin in harmful amounts. As part of a broader effort to reduce hexane emissions, the U.S. EPA introduced new rules for hexane emissions from seed crushing facilities in 2002. Since gasoline contains hexane, almost everyone is exposed to small amounts of hexane in the air. The hexane in gasoline is released into the air at service stations and in automobile exhaust.