We are sure you would have encountered someone who either works in the gold bush or has plans to go into the gold bush. The gold mining sector contributes significantly to the Gross Domestic Product (GDP) of Guyana, and is a source of income and livelihood for more than 17,000 persons.
Mercury, also known as ‘quicksilver’ or ‘silver’, occurs naturally in the earth’s crust. It is, however, highly toxic when used in gold mining activities to amalgamate or bind gold. If gold mining activities are not properly done, using pits, sluice boxes, a retort etc., mercury can be released directly into the environment. Exposure to hazardous fumes can also result in serious health risks.
Mercury and human health
Exposure to mercury fumes affects the nervous and reproductive systems, and damages brain function. Persons exposed to even small amounts of mercury can suffer from symptoms such as tremors, insomnia, memory loss, and headaches. The severity of the impact from exposure to mercury depends on one or a combination of the following factors:
? The form of mercury (for example, methyl mercury or elemental (metallic) mercury);
? The amount of mercury in the exposure;
? The age of the person exposed (unborn babies & infants are the most vulnerable);
? The duration of the exposure;
? The exposure pathway (how the person is exposed – breathing, eating, skin contact, etc.) and;
? The health of the person exposed.
How does mercury end up in our system?
Mercury readily seeps into water bodies, where it builds up and changes form into a chemical known as methyl mercury. This form of mercury is easily taken up by tiny organisms which are eaten by small fishes. The small fishes may be eaten by bigger fishes, the bigger fishes may be eaten by an even bigger fish, and eventually by people. Therefore, with each fish eaten, methyl mercury builds up in higher amounts. This process is known as bioaccumulation, where the level of toxicity increases as it moves up the food chain.
Additionally, people can eat fish contaminated with mercury which isn’t gotten rid of by cooking.
The Minamata Convention
Due to many issues associated with mercury use, Guyana has been one of the first countries to sign the Minamata Convention on October 10, 2013. The Minamata Convention on Mercury is an international treaty designed to protect human health and the environment from human-induced emissions and releases of mercury and mercury compounds. Over the years, a number of proactive steps have been taken to encourage adoption of safer practices. One such step has been the establishment of a National Working Group to guide the development of a National Action Plan which would aid in institutionalization of measures for the reduction of mercury use. Among the actors on this National Working Group are regulatory agencies, government ministries and non-governmental organisations.
Another important action taken towards better mining practices has been the development and/or promotion of options for mercury-free mining. There are several alternative technologies that do not require the use of mercury, including gravimetric processing, which is the easiest entry option.
Panning, sluices and shaking tables are also applicable, and offer a gold recovery rate of 71-75% free gold.
These methods will not only protect the environment and public health from exposure to mercury, but also contribute to Guyana meeting its obligations under the Convention.
Sources
https://nre.gov.gy/2017/08/18/government-reiterates-its-commitment-to-minamata-convention/
https://www.epa.gov/mercury/health-effects-exposures-mercury
https://www.planetgold.org/guyana#:~:text=planetGOLD%20project%20sites%20in%20Guyana&text=Small%2Dscale%20gold%20mining%20is,exposing%20themselves%20to%20hazardous%20fumes.
