Thirty-two tonnes of dead fish have been cleared out of the lagoon where Olympic rowing and canoeing events will take place at Rio 2016.

More than 60 people from the Brazilian city's sanitation department have been removing the fish from the Lagoa Rodrigo de Freitas over the past week.

Some experts believe pollution is to blame, while others claim it is down to a sudden drop in water temperature.
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In January, Brazilian government officials admitted they would miss their target of an 80% reduction in water pollution by the start of the Olympics.

http://www.bbc.co.uk/sport/0/olympics/32326025

Unless Brazil makes headway in cleaning up its waters, experts warn the Summer Games could pose health risks to athletes and mar what officials hope will be their global showcase event. Instead of the soaring vistas of Sugarloaf Mountain, the world could instead see old couches in the bay and tons of dead fish floating atop a city lake. Rio's Olympic committee has pledged in writing that the pollution problems will be fixed, and many had hoped the Olympics would force authorities to tackle decades of neglect and poor planning that have blighted waterways.

http://www.democraticunderground.com/112757941