Copper is most commonly found in pennies, electrical wiring, and some water pipes. It is also found in many alloys, such as brass and bronze. Copper is extensively mined and processed and is primarily used as a metal or alloy in making wire, sheet metal, pipe, and other metal products. Copper compounds are most commonly used in agriculture to treat plant diseases, for water treatment, and as preservatives for wood, leather, and fabrics. Most copper is released to land by mining operations, agriculture, solid waste, and sludge from sewage treatment plants.
Copper is released to water from soil and industrial and sewage treatment discharge.
Much of this copper is attached to dust and other air particles. Some copper in the environment, however, is less tightly bound to particles and may be absorbed by plants and animals. Dissolved copper compounds commonly used in agriculture, for example, are more likely to threaten human health. Copper can enter the body by ingesting water or food, soil, or other substances that contain copper, or by inhaling copper dust or fumes. Drinking water that contains higher levels of dissolved copper is a common pathway.