by Lancel Joseph
The destructive extraction of gold is a major source of public health risk worldwide and has caused a high degree of environmental complications as well as societal problems. The negative impact of the “global gold rush” on humanity is particularly witnessed in developing countries that are heavily overwhelmed by poverty and weak economies. Destructive extraction of gold is particularly prevalent in African countries such as Tanzania, where extraction is not only a hazard in mining areas, but also contributes to downstream problems and negatively impacts the ability of communities to earn income.
The amalgamation of gold is a simple extraction process that entails the separation of gold from the gold-mercury amalgam by burning. It produces a vaporized form of mercury that people are exposed to via inhalation.1 This mercury accumulates in the food chain and becomes even more toxic when it transforms into methyl mercury. Methyl mercury pollutes soils, sediments, and lakes, which consequently contaminate fish and other food sources. Fish are a staple food for many developing countries. Over time, mercury becomes absorbed and heavily concentrated within protein-enriched meals and ascends the marine food chain. Community residents consume the fish, resulting in high toxic exposure to mercury. It is estimated that more than 100 million people around the world are exposed to mercury from small-scale mining.2
With the current gold mining process, methyl mercury in the food chain is becoming an invisible epidemic. The deleterious effects of mercury on the human body are well documented and have grabbed the attention of concerned humanitarians worldwide. Exposure to mercury as an adult can cause damage to localized areas of the brain, causing paresthesia (an abnormal tingling sensation), ataxia (a loss of full control of bodily movements), and other sensory abnormalities.4 Mercury poisoning has an even greater detrimental effect on pregnant women. Prenatal exposure to methyl mercury has adverse effects on a child’s cognitive and neuromuscular development.4 Effects are even seen in children breast-fed by mercury-contaminated mothers.
Due to the unstable Tanzanian economy, large mining companies own more than 90% of the mineral-rich land in the Geita region.2 Difficulty in attaining micro credit and money forces poor citizen groups to partake in hazardous and illegal gold mining. In 2007 and 2008, the President of Tanzania urged large mining companies to work in cooperation with the indigenous people. Cooperation would encourage improvement of technology and development of safety protocols that would diminish the hardships being inflicted upon poor small-scale miners. The ultimate goal would have been to combat both the economic shortcomings of his people and reduce health hazards for everyone.3 However, no action has been taken as of yet.
Ironically, some mining companies have switched from using mercury to cyanide.3 Unlike mercury, cyanide does not bioaccumulate. However, it is an extremely dangerous toxin, and it may pose an even greater health risk than mercury. Is this really the best solution? Are these mining industries really concerned about the people of Tanzania?
It is imperative that the public becomes more aware of the implications of small-scale mining in developing countries. Without increasing awareness, the enactment of laws and legislation is unlikely. Mercury contamination due to gold mining not only affects Tanzania, but also affects many other mineral-rich developing countries impeded by industrial exploitation. The onus is not only on industries to change gold amalgamation processes, but also on developing countries to protect the health of current and future generations.
Picture credits: http://blogs.reuters.com/mark-jones/2009/07/02/finbarr-wins-best-photo-in-diageo-awards/;http://blogs.reuters.com/africanews/2009/09/28/can-gold-save-burkina-faso/
1) Onyemaechi et al. “Modern Environmental Health Hazards: A Public Health Issue of Increasing Significance in Africa.” United States 2008.
2) Veiga et al., 2005 “Reducing mercury and responding to the global gold rush.” 2005, pp. 2070–2072.
3) Spiegel, Samuel J. “Occupational health, mercury exposure, and environmental justice: learning from experiences in Tanzania.” American Journal of Public Health, 2009 Nov.
4) Mozaffarian et al. “Fish Intake, Contaminants, and Human Health-Evaluating the Risks and the Benefits.” American Medical Association, 2006 Oct.