Trembling and irritable, at times psychotic, the hat makers of 19th century England were know to be a bit odd, at best.
Separating fur from animal skins, they washed them in a compound called mercury nitrate, a process that released vapours into steaming air already choked with fumes.
In the poorly ventilated workshops of the industrial revolution, prolonged exposure led to mercury poisoning and eventually the phrase, 'as mad as a hatter'.
The types of conditions that put industrial workers at risk of mercury poisoning have long been banned in the west, with the EU going as far as forbidding the sale of mercury thermometers to the public in 2008.
But in Africa, hazardous conditions still exist. Small scale miners use mercury to extract gold across the continent, with the numbers rising as the precious metal has tripled in price, from $513 an ounce in 2005 to $1700 this year.
Used as a cheap and fast method of extracting gold, the mercury attaches itself to the metal, making it easier to separate it from rocks and other material. Fast, simple, and intuitive, it’s a popular and relatively cheap method for miners with little capital.
Most of it is then released into the environment, with 70 per cent of it usually finding its way into water systems, posing long-term risks for mine workers and communities who live downstream or downwind from areas being mined.
'Gold mining communities are especially vulnerable' says Carolyn Vickers of the World Health Organisation. 'It gets into the food chain, into the fish women eat and then passes into the baby in the womb, which impacts the development of their brains and affects their ability to think.'
Communities in Africa are especially vulnerable, says Abiola Olanipekun, Chief Environmental Scientist at Nigeria’s Ministry of Environment, as the gold boom has been most pronounced there.
UN treaty on mercury?
'Africa needs alternatives (to mercury) so that the environment and people's futures aren't jeopardised. ' This week, Olanipekun joined representatives from 120 governments around the world at the headquarter of the United Nations Environment Programme (UNEP) in Nairobi, where negotiations towards a global treaty on mercury, the most poisonous, naturally occurring substance known to man, are taking place.
Known as the Intergovernmental negotiating committee, its main aims are to:
- Reduce the supply of mercury onto the market
- Reduce mercury demand for products, processes and international trade
- Reduce atmospheric emission of mercury
- Addressing mercury-containing waste and remediation of contaminated sites
The participants are working towards a treaty by 2013, and have already drawn up a draft text. Calling for restrictions in the mercury trade and a prohibition on the dumping of mercury waste in developing countries, it emphasised that financial and technical assistance needed to be given to developing countries.
But even then, implementing it is not expected to be easy. The international trade in the toxic metal is largely unregulated, meaning much of it finds its way into Africa through batteries, light bulbs and other products shipped to the continent as waste.
The surge in small-scale gold mining
Meanwhile, most of the 55 countries where small-scale gold mining is widespread lack the political will and the capacity to prevent it from falling into the hands of 10 to 15 million poor miners who use it.
'A lot of countries are still in denial as to the affects of AGSM (artisanal and small scale gold mining)', says Ludovic Bernaudat of the United Nations Industrial Development Organization (UNIDO). Artisanal mining releases 1,000 tonnes of mercury into the environment every year, which accounts for 30 per cent to 40 per cent of the world’s man-made mercury pollution, a situation that has got worse over the past decade.
Like Canada’s Klondike gold rush, which caught the imagination of 100,000 amateur miners during the 1890s, hundreds of thousands of ordinary people across Africa have flocked to gold fields from Tanzania to Nigeria, where they use mercury liberally, often at risk to their own health.
'It occurs in rural areas where few alternatives exist for livelihood options. It’s done mostly informally, so there is little information as to the number of them and the amount of mercury released into the environment' adds Bernaudat.
However, 'It is an attractive alternative income' for a lot of people says Kevin Telmer, a geochemist at the University of Victoria in Canada, meaning that it is unrealistic to expect people to stop using mercury unless realistic alternatives are offered to them.
In Burkina Faso, he says a government survey found that 600,000 people were living on gold mining settlements. Of these about 1/3 were directly involved in gold mining, producing roughly half a gram of gold a day.
'The miners form small groups and get about 75-80 per cent of the international price,' he says, making an average of $5,000 a year. High costs mean they save about 10 per cent he says, which is 'a higher savings rate than in the U.S. or Europe.'
His organisation, the Artisanal Gold Council, is working with small scale gold miners in developing countries such as Burkina Faso to formalise their businesses, helping them to draw up business plans and adopt safer mining practices. It is hoped that doing so will lead to the implementation of pollution prevention measures that limit mercury contamination of water sources.
The introduction of safer gold mining practices such as such as gravity separation, which simply uses gravity to separate heavier gold from the rest of the ore without using chemicals such as mercury, is one such way. Using containers called 'retorts', which capture the mercury vapor, is another method.
However, making the industry more environmentally friendly still does not address another proble: child labour. One million children work in artisanal gold mining in Asia, Latin America, and Africa, according to the International Labour Organisation.
'Governments have done far too little to protect children from mercury exposure and to end child labour in artisanal mining,' says Juliane Kippenberg, senior children's rights researcher at Human Rights Watch.
'The treaty should not only address mercury as a technical environmental issue, but also as a right-to-health issue. With this treaty, governments can save hundreds of thousands of children from mercury exposure, and ultimately, from poisoning.'
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