A 2016 report by researchers for the International Institute for Environment and Development estimated a million people in Ghana make a living in what some call artisanal mining, and 4.5 million more depend on it. Sub-Saharan Africa is home to almost one crore such miners, according to a World Bank estimate: At least 6 crore more are reliant on the sector. As miners go for gold, they are poisoning rivers, farmland - and themselves. Miners inhale fumes from explosives used to loosen rocks, and dust coming off crushing machines, which contains heavy metals such as lead. This weakens the lungs.
They use mercury and nitric acid, which also cause breathing problems, to leach precious ore out of sediment. Then they toss the chemicals to the ground or into rivers.