World Aquatics cancels Olympic practice swim Tuesday amid concerns about Paris' Seine River

Competitors in the Olympics marathon swimming event weren’t allowed to practice and familiarize themselves with the Seine River Tuesday after World Aquatics canceled a test run.

The concern, as it’s been since the Opening Ceremonies, is the water quality in the Seine, which runs through the center of Paris and alongside some of the city’s most stunning landmarks.

The Associated Press reported that the cancellation was because of fluctuating bacteria levels. The Olympics already have seen triathletes swim in the Seine, but not after some issues.

There will be another test Wednesday. Organizers will make a decision then on whether to allow the marathon events for men and women to continue in the Seine. The women’s marathon swim is scheduled for Thursday with the men following Friday.

Both the triathlon and the swimming marathon used the Pont Alexandre III as the starting points. However, the marathon swimmers will stay in the water longer than the triathletes. They’ll do six laps of a mile-long course.

Previously, organizers canceled some of the triathlon test sessions in the Seine. But the events were held. However, the Belgians forfeited its spot in the mixed triathlon event. Claire Michel, one of the competitors, became sick after swimming in the Seine last Wednesday. The Belgian Olympic committee did not blame the Seine for Michel’s infection. But the newspaper De Standaard reported that the triathlete was hospitalized and treated for an E. coli infection.