On the outskirts of Ghana's biggest city sits a smoldering wasteland, a slum carved into the banks of the Korle Lagoon, one of the most polluted bodies of water on earth. The locals call it Sodom and Gomorrah. Correspondent Peter Klein and a group of graduate journalism students from the University of British Columbia have come here as part of a global investigation -- to track a shadowy industry that's causing big problems here and around the world.

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