Chacha Mwita an artisanal miner at Ikungi mines in Butiama District, Mara Region extracts gold from muddy water believed to be contaminated with mercury. (Photo: Dickson Ng'hily)
The use of mercury to extract gold poses potential health risk to artisanal miners (ASM) and the environment at Ikungu mines, Butiama District.
Small scale miners use the chemical element as an enhancement to ‘capture’ gold in their operations yet unknowingly they jeopardise their health and pollute the environment.
Speaking to this paper, Chacha Mwita, who is a small miner in the area explained that the use of mercury gives them the ability to have more gold as it has the great capacity to ‘capture’ the metal.
“We have no alternative to mercury in gold mining …we don’t know the side effects and by the way, I have been in this business for some time now, exposing myself to the metal, yet I haven’t had any side effects,” he said with confidence.
He added: “Look at that pile of clay, there’s gold over there…if you don’t use mercury then you will get nothing and since you don’t have any other way of extracting the metal from it you will defiantly come to the dreaded mercury as your solution.”
Another miner, James Wanyancha said: “Our capital is limited, we can hardly manage this business if we don’t use mercury as it help us a lot…if we had enough capital then we would purchase big machines to help us in this extraction business.”
Wanyancha, who also seemed unaware of the risks posed by exposing himself to mercury said: “I joined this business when I was 14, and I am currently 45, therefore, if it at all it was harmful, I would have known long time ago.”
According to him, after they are done with their search for gold, they discharge mercury waste into the lake (Victoria) causing biological processes that transform the chemical substance into methylmercury, a highly toxic and bioaccumulative form.
It is said that fish can absorb methylmercury from their food and directly from water as it passes through their gills—the respiratory organ found in many aquatic organisms that extract dissolved oxygen from water, afterward excreting carbon dioxide.
According to World Health Organisation (WHO) fact sheet, mercury and all of its compounds are toxic, and therefore exposure to excessive levels can permanently damage or fatally injure the brain and kidneys.
It can also be absorbed through the skin and cause allergic reactions while ingestion of inorganic mercury compounds can cause severe renal and gastrointestinal damage.
WHO fact sheet indicates that the organic compounds of mercury such as methylmercury are considered the most toxic forms of the element, therefore, exposures to very small amounts of such compounds can result in devastating neurological damage and death.
For fetuses, infants and children, the primary health effects of mercury are on neurological development, it is said that even low levels of mercury exposure that result from mother's consumption methylmercury in dietary sources can adversely affect the brain and nervous system.
The United Nation News Centre’ post indicates that the use of mercury remains a major global, regional and national challenge in terms of threats to human health and the environment.
The post quote the United Nation Environmental Program (UNEP) Ache Steiner UNEP executive director as saying: “...but today we have many of the alternative technologies and processes needed to reduce the risks for tens of millions of people, including pregnant mothers and their babies,”
Therefore, the need for swift action by government, industry and civil society to strengthen efforts to reduce mercury emissions and releases is needed otherwise the delays in action, according to the UN agency, will lead to slower recovery of ecosystems and a greater legacy of pollution.