Athletes, coaches and organizers at a major test event for next year's Olympic Games shrugged off a simmering dispute over safety at watersports venues by diving into the controversial waters off Copacabana Beach on Saturday.

The first day of the triathlon world championship event saw para-athletes swim in the Atlantic waters and bike and run in the streets nearby.

"I'm not concerned about the water," said Alison Patrick, a blind British athlete who won the P-5 women's' triathlon in partnership with her sighted guide Grace France.

"The thing I noticed most was that the water was warm. I'm from Scotland and I'm used to much colder water."

The waters will be used for triathlon, ocean swimming and sailing events during next year's Olympics in Rio de Janeiro, the first to be held in South America.

Elite men's and women's triathlon events, scheduled for Sunday, offer qualifying spots for next year's Games.

Concern over the athletes' health in the waters arose last week after an Associated Press report showed viral and bacterial levels in the water are equivalent to those in raw sewage.

Rio de Janeiro's state environmental agency declared some waters near the swimming site unsuitable for bathing on Friday but the worries did not seem to bother most competitors.

Rodrigo Garcia, director of sports for the Rio Olympic Organizing Committee said bacteria levels in the water is within Brazilian and international standards.

Garcia said the committee has backup plans if heavy rains wash sewage into the venues.

Doug Hiller, medical officer for the International Triathlon Union said he was giving no special recommendations to athletes about Rio water quality.

"If I didn't have to work so hard today, I'd be in the water myself," he said.

Patrick and France said they took antibiotics and vitamins before the event and gargled with mouthwash afterward.

Some athletes, though, just ignored their concerns and fought through to the finish.

Blind U.S. triathlete Patricia Walsh of Austin, Texas who came in third in the P-5 event, was most concerned about the waves.

"The chop worried me most," she said. "It was hard to hear my partner, we usually only get to train in calmer waters," she said.

Her sighted guide Missy Kuck was less sanguine.

"I wasn't really concerned," Kuck said. "But let's be honest, the water was nasty."

(Reporting by Jeb Blount, editing by Gene Cherry)