BBC visits the world’s mining capital for rare earths in China bbc.co.uk/news/resource…: Poisoned water and scarred hills - The price of the rare earth metals the world buys from China. We found man-made lakes full of radioactive sludge and heard claims of polluted water and contaminated soil, which, in the past, have been linked to clusters of cancer and birth defects. These journeys were challenging. Beijing appears sensitive to criticism of its environmental record. We were pulled over by police, questioned by them and stuck in a three-hour standoff with an unidentified mining boss who refused to let us leave unless we deleted our footage.