The governing body of world sailing has threatened to move all sailing events out of Rio de Janeiro's polluted Guanabara Bay at next year's Olympics unless the water is made cleaner and floating rubbish is removed.
International Sailing Federation chief executive Peter Sowrey said if the water quality doesn't improve then the Olympic sailing events will be moved further out into the Atlantic Ocean.
Local Olympic organisers and the International Olympic Committee have repeatedly said the water is safe, despite being filled with floating rubbish and untreated sewage that gushes down gullies from hillside favelas.
Sowrey said one course inside the bay used at last week's Olympic test event was closed after floating rubbish hindered racing for two days.
He also complained he received no data during the week-long test from the state body that monitors water quality.
The New Zealand 49er sailors Peter Burling and Blair Tuke won gold at the test event while their team-mates Jo Aleh and Polly Powrie claimed bronze in the 470.