The Biological Importance of Copper

International Copper Association (ICA) literature reviews are stored as Adobe Acrobat documents. To view them you must have the Adobe Acrobat reader installed on your computer. Because each year's review is stored as a single file the files are relatively long and may take some time to download.

The International Copper Association (ICA) has conducted annual reviews on the biological importance of copper since 1984. The reviews conducted since 1989 are available here. The reviews have addressed four basic questions:

  • What does copper do to organisms?
  • What are the sources of environmental copper?
  • What happens to copper once it enters the environment?
  • What are the relationships between the chemistry of copper and its biological importance?

Copper is required for the normal functioning of plants, animals and most microorganisms. It is incorporated into a variety of organics which perform specific metabolic functions. Because it is an essential metal, daily dietary requirements have been recommended by a number of agencies. The American Medical Association has recommended 1.2 - 1.3 mg/day as the dietary requirements for copper.

The chemical nature of copper is very important in determining its biological availability, both in the environment and in food. Although evidence of this continues to accumulate, the impact of excess copper is still far too frequently inferred from levels of "total copper" or even the "presence" of copper.

Some of the uses of copper come from its ability to control the growth of organisms. This occurs when copper is biologically available and at concentrations that are detrimental. As a result, copper is used in a range of cidal agents. For example, copper has been demonstrated to be an effective antibacterial, antiplaque agent in mouthwashes and toothpastes. Copper also continues to be widely used for the control of unwanted organisms in fish farming. Evidence in both fresh water and salt water indicates no hazardous effect to consumers of the fish. Copper antifouling agents used on fish net pens have been considered a source of metal to the sediments but there is little evidence that they provide an important source of dissolved copper when there is adequate water exchange for fish farming.