Multiple athletes competing in the swimming events at the Paris Olympics have reportedly fallen ill after swimming in the Seine river, raising concerns over the water quality. The safety of athletes participating in water-based events has been a growing concern leading up to the Games.

Speculation heightened when the swimming portions of practice sessions were canceled due to water quality concerns. Athletes expressed dissatisfaction with the conditions during the men's and women's individual triathlons on July 31. Amidst these concerns, news broke over the weekend that several competitors had fallen ill after swimming in the Seine.

On August 4, Belgium made the decision to withdraw from the mixed-relay event after one of their athletes, Claire Michel, was reported to have contracted an E. coli infection. While it is yet unclear whether her illness is linked to the other cases, this development underscores the safety concerns expressed by athletes and public health experts since it was announced that Olympic events would be held in the Seine river.

According to microbiologist and professor Bill Sullivan, the Seine river has been notoriously polluted for years due to sewage and soil erosion. The combination of these factors leads to the presence of harmful pathogens such as E. coli, Cryptosporidium, and Giardia in the water.

Contrary to popular belief, heavy rain, like the downpour experienced in the days leading up to the triathlons, actually increases the risk of contamination as it washes all the waste from the land into the river. Despite last-minute test results being deemed compliant by World Triathlon, athletes and experts remain concerned about the reliability of these tests in ensuring swimmer safety.

Although measures like taking probiotics before swimming and thorough disinfection after swimming have been implemented by certain teams, they do not provide a foolproof solution. While probiotics may help reduce the severity and duration of symptoms, they cannot prevent illness entirely. Similarly, disinfection practices are effective in reducing the risk of skin infections, but swimmers are still advised to shower and wash their hands thoroughly with soap and water to minimize the transmission of pathogens.

The marathon swim scheduled for August 8 and 9 in the Seine river is set to proceed, but a contingency plan has been put in place to relocate the event to the Vaires-sur-Marne Nautical Stadium if water quality deteriorates.

The concerns over water quality at the Paris Olympics highlight the need for thorough assessment and robust measures to ensure the safety of athletes participating in water-based events. As the Games continue, health experts and officials must prioritize the well-being of athletes and take necessary steps to mitigate the risks associated with swimming in polluted waters.