MOSCOW (AP) -- Swimming's governing body FINA has called for virus testing in water which will be used at next year's Olympics following fears for athletes' health.
Until recently, games organizers insisted viral testing was not necessary, despite an independent five-month analysis by The Associated Press showing dangerously high levels of viruses from human sewage at all Rio Olympic water venues.
The AP study showed that the spot where athletes will enter the water on Copacabana Beach for marathon swimming and triathlon events had a minimal reading of over 2 million human adenovirus per liter - 2,000 times the reading that water experts in the U.S. say would be considering highly alarming if seen on beaches in the U.S. or Europe.
"FINA and its Sports Medicine Committee strongly recommend that viral tests should also be performed," says a FINA letter addressed to games organizers and Rio mayor Eduardo Paes, and obtained by the AP.
"It is very important for FINA that all athletes competing in the marathon swimming event in Rio 2016 Games can compete in an environment free from any bacterial or viral contamination."
FINA said it and Rio state institute INEA are "conducting tests on the water of the Copacabana Beach in order to ensure that during Games time, the athletes will have the best conditions to compete, namely concerning their health and safety."
It was not clear which specific tests FINA and the INEA were conducting.
Games organizers agreed to test for viruses earlier this month after earlier insisting that only bacterial testing was required.
Concerns over water quality also affect other outdoor water events, such as sailing, the governing body of which has already said it will test for viruses. Some competitors training in Rio have reported falling sick.
"What I know up until today from the athletes that take part in the test events that there is nobody with any kind of health difficulties after two, three, four weeks or what it is," FINA executive director Cornel Marculescu told the AP on Wednesday.
"We continue to monitor it together with the Brazilian agency, doing regular tests on the quality."
AP Sports Writer Andrew Dampf in Rome contributed.