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"Five and a half kilometres above sea level, Rinconada is the highest shantytown in the world. Rinconada - which means corner in Spanish - has become a hideout for the desperate and those on the run from the authorities. In this town there is no drinking water, there are no toilets and no sewers - just an open trench in the middle of the main road where the rubbish and excrement is deposited in the open air. The smell is unbearable. The situation is now so bad that some observers say the drinking water of over one million people is threatened with contamination.
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The trench at Rinconada can only absorb a tiny proportion of the town's rubbish. The majority is dumped between the houses or in the immediate surroundings of the town. The excrement and rubbish has been piling up day after day, around the houses for dozens of years. Disease is commonplace, especially among children. Assisted by two nurses and a midwife, Hernán Ventura Chambilla is the only doctor in Rinconada. "The population of Rinconada is, without a doubt, the urban population living at the highest altitude in the world," he tells TVE. "Unfortunately, this population lives in the middle of its own excrement and rubbish. It's incredible, but everything is dumped anywhere at all, out in the open.
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In days gone by, the lake was considered a source of pure water. But today it carries the pollution from Rinconada downstream. The mine pollutes the Rio Carabaya which, after travelling 250 km, flows into Lake Titicaca. The authorities seem to think that small-scale mines only cause local pollution. In fact, small-scale mines are having an impact on the ecosystem of the entire country. Mines throughout Peru release 100 tonnes of mercury each year; 80 tonnes in liquid form and 20 in gas. According to the Ibero-American Programme for Science and Technology in Development (Cyted), most of the main rivers in the south of Peru are contaminated by mercury. As yet, there is no official record of contamination levels.
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The gas comes out through chimneys, directly onto the roofs of houses. In contact with cold air, the mercury condenses and is deposited around the chimneys. Between two and three tonnes of gold a year are produced at Rinconada, releasing four to six tonnes of mercury into the air. As there is no drinking water Rinconada, the inhabitants collect the melting snow from their roofs and use it for their personal consumption. The mercury is ingested directly by the miners and their families. The metal attacks the nervous system; commonly making people more aggressive and leading to serious problems in limbs and internal organs. It may be one reason for the appalling levels of domestic violence in Rinconada."
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http://news.bbc.co.uk/1/hi/sci/tech/4032911.stm