Reducing levels of pollution on the Bay was heralded as one of the great legacy aims of Rio de Janeiro's initial bid for the Games in 2009, with officials aiming to engineer an 80 per cent reduction by the time of the Games. 

But the issue has provoked huge criticisms in recent month, with many concerns voiced over the safety of sailors competing on the Marina da Glória amid some calls for the event to be moved further out to sea into cleaner waters away from the host city.

International Sailing Federation officials have expressed their fears and President Carlo Croce and vice-president Scott Perry met with International Olympic Committee (IOC) officials, including President Thomas Bach, to discuss the issue.

Rio de Janeiro Mayor Eduardo Paes also admitted "an opportunity had been missed" to use the Games as a catalyst to enable a greater reduction of levels.

Speaking here today alongside Rio 2016 President Carlos Nuzman and Brazilian Sports Minister George Hilton, Marco Antônio Cabral, the Secretary for Sport within the State Government responsible for reducing levels, insisted they were doing all they can and, although a "concern", was not a major worry.

"From only 11 per cent in 2007, levels have now been reduced by 50 per cent," he said.

"Of course, what we want is to have it 100 per cent cleaner but there has been a huge effort and it is four-times cleaner now."

"For the Olympic Games, there will be no problem around the Bay. 

"The main problem is the trash floating around the Bay but we have deployed special collection boats and this will all be collected."

As Cabral pointed out, Dutch Research Institute Deltares was appointed earlier this year to conduct a study into the Bay in order to pinpoint areas where rubbish is likely to accumulate, but progress was halted due to a lack of boats to physically collect the rubbish.

This was because the Government had not agreed a contract to purchase them, insidethegames was told.

In April, Rio 2016 communications director Mario Andrada told insidethegames that contracts had still not been agreed and that the Organising Committee "needed to work with the Government and put pressure on them to react".

Cabral revealed today that boats had been purchased and the clean-up operation had begun "last month".

The official, one of five speakers in a presentations highlighting what all claimed were positive aspects of progress in the build-up to Rio 2016, also spoke optimistically about efforts to reduce levels on the Lagoa Rodrigo de Freitas where rowing and canoe sprint competitions will be held.

A major test for sailing will come in August when a second test event is due to take place on the Bay from August 15 to 22.

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