Gold fever is driving Amazon loss and mercury pollution in Peru

By Martin Leggett - 19 Apr 2011 21:1:0 GMT
Gold fever is driving Amazon loss and mercury pollution in Peru

The soaring price of gold is being held responsible for a massive increase in the deforestation of parts of the Amazon. A rush of impoverished miners are blasting their way through the Peruvian rainforests in the south-east of the country, in the hope of striking their fortunes. A paper published today in PLoS ONE has picked up on a six-fold leap in deforestation in the Madre de Dios region.

Additionally, increasing quantities of toxic mercury, used to extract the precious metal from the river gravels, are poisoning miners, and flowing out into the rivers and oceans. That has long-lasting toxic effects that accumulate up the food chain - and is already causing problems for endangered marine life.

The Madre de Dios area of Peru lies on the western fringes of the Amazon basin, and its river banks have been exploited for gold since the time of the Incas. But in recent years increasing numbers of small-scale 'artisanal' miners have arrived, looking to find a way out of their lives of poverty. That is putting increasing pressure on a previously pristine ecosystem - but getting a handle on the scale of the problem is difficult in such a remote area.

For this paper, a group of scientists, directed by North Carolina's Duke University, has been using NASA satellite images, and economic data, to assess the impact of gold miners on the area. The small-scale independent mines are clustered along river banks, where the gold has accumulated in thick gravel and sand beds. In order to dig up these deposits, the miners are blasting away river banks and leveling tracts of the forest - damage which shows up distinctively on the satellite images.

Around 15,000 acres of forest has been cleared around the two largest mining areas, from 2003 to 2009. That pace of destruction has picked up considerably in the last 3 years - and is clearly linked to recent hikes in the price of gold, says the team. Gold is the ultimate financial refuge, in turbulent times, and has seen its value treble over the last 6 years of war and recession. Recent turmoil in the Middle East, has had gold peaking at over $1400 per ounce.

As well as deforestation, mercury pollution is also an extremely worrying feature of this Peruvian gold rush. This toxic metal is being widely used to extract the gold by poor miners - who often have little knowledge of the environmental impacts - even to the detriment of their own health. Mercury poisoning can have severe effects on the nervous system and on brain development.

The miner's need for mercury may hold the key for improving the situation, however. ''Virtually all mercury imported to Peru is used for artisanal gold mining and imports have risen exponentially since 2003, mirroring the rise in gold prices,'' says Jennifer Swenson from Duke University. If mercury imports were restricted and carefully regulated, that may help bring the small mines under better control, and so slow the needless environmental destruction and pollution.