Gold Mining

One of the most controversial uses of cyanide is in the gold mining industry. Gold typically occurs at very low concentrations in ores. To economically extract the gold from the ore at these low concentrations, a complicated chemical extraction process, called leaching, is employed. During this leaching step, the gold must be dissolved in a liquid to be separated from the residues. However, gold is not soluble in water, and therefore a complexant, such as sodium cyanide, is required to dissolve gold.

Environmental groups often criticize the industry's use of cyanide and the potential for contaminating the human water supply and also the potential harm to the plant and animal environment. From 1987 to 1993, according to the Toxics Release Inventory cyanide compound releases to land water totaled 1.5 million lbs. In contrast, the mining industry has argued that the cyanide is diluted and poses very little danger to the environment. However, some states, such as Montana, and other local municipalities across the world have banned the use of cyanide in mining.

At least six of the world's largest gold producers, together with three manufacturers of sodium cyanide have publicly announced their commitment to the International Cyanide Management Code. The Code is a voluntary industry program that provides comprehensive guidance for best practices in the use and management of cyanide at gold mines. This code goes beyond requirements of most governments and regulatory agencies and covers nine key areas: production, transportation, handling and storage, operations, decommission of facilities, worker safety, emeregency response, training, and communications with the public. The Code was developed by a steering committee of multi-stakeholders under the auspices of the United Nations Environment Programme and the International Council on Metals and the Environment.

	Number of Known Cyanide Users, Processors, Manufacturers, Distributors and Cyanide Waste Receivers and/or Generators per 1,000 persons by County