The use of cyanide in the gold-mining industry has been ongoing for a very long time. However, in more recent times, it has resulted in serious environmental damage and health problems for people.

Large numbers of species of flora and fauna have been endangered while people have been lethally poisoned through pollution of natural water systems.

Consequently, the problem has been drawing the attention of environmentalists and international organisations which deal with environmental and health issues and, eventually, an International Gold Mining Code was formulated governing the use of cyanide in the gold mining industry.

According to experts, gold typically occurs at very low concentrations in ores – less than 10 g/t or 0.001% (mass basis). At these levels of concentrations, the use of aqueous chemical (hydrometallurgical) extraction processes is the only economically viable method of extracting the gold from the ore.

Typical hydrometallurgical gold recovery involves a leaching step during which the gold is dissolved in an aqueous medium, followed by the separation of the gold-bearing solution from the residues, or absorption of the gold onto activated carbon.

After elution from the activated carbon, the gold is further concentrated by precipitation or electro-deposition.

Approximately 1.1 million tonnes of hydrogen cyanide are produced annually worldwide, with approximately 6% used to produce cyanide reagents for gold processing. The remaining 94% is used in industrial applications including production of plastics, adhesives, fire retardants, cosmetics, pharmaceuticals, food processing and as an anti-caking additive for table and road salts.

Cyanide is acutely toxic to humans. Liquid or gaseous hydrogen cyanide and alkali salts of cyanide can enter the body through inhalation, ingestion or absorption through the eyes and skin.

The rate of skin absorption is enhanced when the skin is cut, abraded or moist; inhaled salts of cyanide are readily dissolved and absorbed upon contact with moist, mucous membranes.

It is therefore absolutely essential that the use of this very harmful chemical be handled in accordance with safe environmental and health practices.

Here in Guyana, gold mining is a big industry and has been expanding with increasing investments and therefore, greater attention has to be placed on health and environmental safety as mining activities take place in many communities that have a variety of flora and fauna, some of them are rare or endangered species, as well as having a relatively dense population.

On this note, the Guyana Geology and Mines Commission (GGMC) has been increasingly focusing on safe mining practices and has spearheaded, in collaboration with miners, several initiatives such as education and awareness activities. In addition, many outdated laws and regulations governing the mining sector have been revised or updated and new ones have been implemented.
However, there has been a recent landmark agreement clinched between the Canadian International Development Agency (CIDA) and the GGMC. Under the agreement, a grant of Cdn$100,000 to build technical capacity at the GGMC for the introduction of cyanide leaching to improve small-scale gold recovery will be provided by CIDA.
Prime Minister Samuel Hinds noted that the small and medium-scale mining sector faces significant challenges at this time. He said one of the challenges is the need to find lawful ways to recover gold without the use of mercury. The Prime Minister said GGMC is leading the way in terms of research to find ways of improving recovery and using safer methods to mine gold.

The global environmental situation necessitates safer mining methods and practices as the world has been already  plunged into such a polluted state that it cannot handle and adding further pollutants will be an invitation for disaster.