Steel containers may have originated in 14th century Bohemia. In 1809, a Frenchman invented a process to package preserved food in cans. Three years later, tinplated cans were produced in Britain. In 1938, the first steel beer can was produced.

Steel cans are made from tinplate steel, which is produced in basic oxygen furnaces. A thin layer of tin is applied to the can's inner and outer surfaces to prevent rusting and to protect food and beverage flavors. As a result, steel cans are often called "tin cans." However, a chromium wash is replacing tin in the canmaking process.

Most steel cans are used for food products, followed by paint, aerosols and other products. Steel cans account for more than 90 percent of food cans. More than 600 shapes, styles and sizes of containers are used. The steel can recycling rate has skyrocketed, but the amount and percentage of steel cans in municipal solid waste has declined dramatically in the last 40 years due to competition from lighter aluminum and plastic containers.

Electric arc furnaces primarily use scrap steel while basic oxygen furnaces primarily use virgin raw materials.

Chaz Miller is state programs director for the National Solid Wastes Management Association, Washington. E-mail him at: cmiller@envasns.org.

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