Mercury and Ruin

Mercury and Ruin

In many developing countries, a steady income is worth more than its weight in gold in providing for a family and putting food on the table. In Prestea, Ghana, however, the steady income is gold. Over 150 small gold mines can be found in the little town of ~35,000. The miners use liquid mercury to separate the gold from the other elements found in the soil in their backyards. The use of mercury is so extensive that red smog covers the town and paints the local livestock with a light-red hue. Pictures like this can be seen in the 50+ developing countries in Asia, Africa, and South America where approximately 15 million people use mercury to extract gold out of the earth. The neurological and developmental effects of mercury poisoning are concerning especially when considering the ~3 million women and children who work in environments where liquid mercury exposure is not only routine, it is part  of their livelihood. Mercury exposure in children and developing fetuses is especially concerning as it can impair neurological development resulting in losses in cognitive thinking, memory, attention, language skills, and find motor and visual special skills. Certainly not something we would want our children to be exposed to

Artisanal and small-scale gold mining (ASGM) is the largest consumer of Mercury in the world. Not surprisingly, it also is the largest contributor of mercury air and water pollution combined with only coal combustion contributing more than ASGM in air pollution. Clearly, this is an important issue that the United Nations Environment Programme is holding the Minimata Convention on Mercury from the 9^th to the 11^th of Oct. 2013 to address. The aim of this convention is to adopt a global policy that will protect people and the environment from harmful mercury exposures. This topic must be addressed cautiously as ASGM is a powerful way to bring wealth into an impoverished country. Gold can be sold for 70% or more of international prices making it an excellent commodity for international trade and economic growth. Already, ASGM accounts for 15% of the global gold supply and 90% of the gold mining workforce. Reducing mercury levels may be good for the environment and individual exposures to mercury, but what about the 90% of gold miners that would be out of work with no means to provide for their families? Sure they may not die from mercury poisoning, but I would bet that some of them would rather die from that than starvation.

Mercury pollution is a growing national environmental concern. ASGM, unlike industrial gold mining processes, does not typically practice sound waste management. In some cases, the waste is discharged into rivers adding to the growing concern of mercury in aquatic life. Fish species worldwide contain anywhere from 0.05 to 1.4 mg/kg with fish higher in the food chain accumulating the most mercury. This is concerning as the pervasiveness of the problem is doubly complicated as the consumption of mercury-containing fish and aquatic life is considered to cause the most harm to humans. Other forms of mercury can be inhaled as a vapor and cause effects such as tremors, kidney effects, respiratory failure, and death to name a few. The exposure method of inhalation is quite common in areas where ASGM activity is present. The processed used to extract gold with mercury involves evaporating the mercury from a mercury/gold mixture known as an amalgam. Nearly all vapors of this sort produce mercury levels that exceed the WHO limit of 1,000 ng/m³ for public exposure. These exposures could in many instances be chronic in the sense that mercury is an element and cannot be broken down except for nuclear decay.

This economic, health, and environmental issue is not one that can be easily remedied. Many do not know of mercury’s harmful effects and lack the resources or knowledge to use safer techniques. The prospect of a steady gold income is certainly a boon for the many poor who live in developing countries around the world. But at what cost to their health and the environment? How effective would a program be that empowered ASGM workers with safer, more efficient, and more productive techniques? Would it not increase the wealth of the area, encourage local doctors and nurses to stay in the area (thus curbing the brain drain), better facilitate international trade, provide money for food and clean water, provide a safer work environment, and curb mercury pollution? Perhaps we will find out after the Minimata Convention on Mercury that convenes later on this week. Let us hope this works. I really like my sushi.

UNEP. Reducing Mercury in Artisanal and Small-Scale Gold Mining (ASGM). UNEP. http://www.unep.org/hazardoussubstances/Mercury/InterimActivities/Partnerships/ArtisanalandSmallScaleGoldMining/tabid/3526/language/en-US/Default.aspx. Accessed October 6, 2013.

UNEP. Diplomatic Conference for the Minimata Convention on Mercury. UNEP. http://www.unep.org/hazardoussubstances/MinamataConvention/DiplomaticConference/tabid/105832/Default.aspx. Accessed October 6, 2013.

UNEP. Global Mercury Assessment. UNEP Mercury Programme. http://www.chem.unep.ch/mercury/Report/Chapter4.htm#4.2. Accessed October 6, 2013.

EPA. Heath Effects. EPA Mercury. http://www.epa.gov/hg/effects.htm#content. Updated July 9, 2013. Accessed October 6, 2013.

UNEP. Reducing Mercury Use In Artisanal and Small-Scale Gold Mining. UNEP. http://www.unep.org/hazardoussubstances/Portals/9/Mercury/Documents/ASGM/Techdoc/UNEP%20Tech%20Doc%20APRIL%202012_120608b_web.pdf. Accessed October 6, 2013.

M.C. Gold mining in Ghana: Playing with Mercury. The Economist. http://www.economist.com/blogs/baobab/2013/09/gold-mining-ghana?fsrc=scn/fb/wl/bl/playingwithmercury. Published September 30, 2013. Accessed October 6, 2013.