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The 10 worst pollution problems in the world

By: chief on Oct. 16, 2009, 11:21 p.m.
Drainage water exits a pipe

Photo: Paul Erickson/iStockphoto

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Contaminated surface water

People need at least 70 liters of fresh water daily for drinking, cooking and cleaning. As populations near or along bodies of water become urbanized, their industrial and agricultural waste often seeps into the nearby freshwater supply, making it either unusable or hazardous.