Fifteen members of the United States Olympic rowing team have taken ill and Rio de Janeiro's polluted waters could have caused it.

According to CNN, the American squad was taking part in the 2015 World Junior Rowing Championship in Rio when 15 of its members fell ill after the tournament. The championships took place at the Rodrigo de Freitas Lagoon.

United States Rowing Chief Executive Glenn Merry said that the athletes' sudden illness could have come from anywhere.

"It would be easy but irresponsible for us to immediately assume that the rowing course is the main or sole point of exposure that caused the illnesses. We are not jumping to this immediate conclusion for two reasons," he stated.

According to Al Jazeera, Rio officials said that the polluted waters are not to blame for the athletes being sick. Extensive tests on the lagoon were conducted and found no abnormal levels of viruses or bacteria in the water.

Rio de Janeiro Mayor Eduardo Paes stated that the city's waters pose no threat to the Olympic athletes and their health.

The only athlete that fell into the lagoon was not one of the athletes that became sick. Reports said that the athletes were treated for diarrhea.

Biologist Mario Moscatelli tested the waters of Rio last year and concluded that there is a "superbacteria" that can cause a number of infections. He stated: "If I fell in this water right now I could contract anything from a conjunctivitis to an intestinal disorder or even hepatitis A."

Rodrigo de Freitas Lagoon will host the rowing games of the Summer Olympics next year.