PARIS– At the Paris OlympicsI want the water quality in the River Seine is safe enough hosting some swimming events has been a major issue.
Bacteria levels in the river are constantly fluctuating, and daily water samples are tested so organizers can assess the risk and determine whether swimming in the long-polluted Paris waterway should go ahead.
Triathletes ran in the river wednesday, and organizers said on Sunday evening that Monday’s mixed triathlon relay would go ahead as planned with the swimming portion in the Seine. Testing will continue ahead of marathon swims scheduled for Thursday and Friday.
Here are some things you should know about water quality testing in the Seine:
High levels of E. coli and enterococci indicate sewage or fecal pollution in the water. Most strains are harmless and some live in the intestines of healthy people and animals. But others can be dangerous.
Even a sip of contaminated water can cause diarrhea and can result in illnesses such as urinary tract or intestinal infections.
A person’s susceptibility to becoming ill from exposure to E. coli depends on several factors, primarily the person’s age and general health.
“Generally speaking, the healthier you are, the more likely you are to resist any type of pathogen,” said Brian Rahm, an expert in biological and environmental engineering at Cornell University.
Sometimes, not even E. coli itself is a cause for concern, Rahm said. “When we see E. coli in the water, it indicates that other types of pathogens and other bacteria, viruses may also be in the water.”
The tests help organizers assess the risk to athletes, but it’s difficult to quantify the exact risk using this data, said Metin Duran, a professor of civil and environmental engineering at Villanova University.
“Unfortunately, there is not much you can do before exposure to reduce your risk,” Duran said.
Swiss authorities said on Saturday that triathlete Adrien Briffod, who competed in the Seine three days earlier, fell ill with a stomach infection. But they said it was “impossible to say” whether this was related to his swimming in the river and that other delegations had told them that none of their triathletes had reported stomach problems.
The quality of water in the Seine is closely linked to the climate. Heavy rains cause wastewater and runoff to flow into the river, causing bacteria levels to rise, while the sun’s ultraviolet rays can kill bacteria.
And Paris saw several rain during the Games until here.
To deal with these contingencies, Paris allocated 1.4 billion euros ($1.5 billion) to infrastructure improvements ahead of the Olympic Games, including building a giant basin capture excess rainwater and prevent wastewater from entering the river, renewing sewage infrastructure and modernizing wastewater treatment plants.
Paris Deputy Mayor Pierre Rabadan said these improvements made a big difference.
“We will never prevent rain from having an impact on water quality. This is not possible,” he said. “What we did will allow us to return to satisfactory and good water quality, as was the case in the triathlon.”
Organizers canceled several swimming tests this weekend and last week, the aim was to allow triathletes to familiarize themselves with the course due to concerns about water quality following rain. The men’s triathlon was postponed for a day and was held on Wednesday, the same day as the women’s race.
Decisions about canceling an event were usually made in the early morning hours of race day, but organizers announced on Sunday night their decision to go ahead with Monday’s race to give athletes more time to prepare.
Rabadan said infrastructure improvements prevent wastewater from flowing into the Seine. It rained on Wednesday while the triathletes competed. Wastewater entering the river from upstream would take several hours to reach Paris, meaning water quality levels were still safe at the time of the run, he said.
Since then, there was heavy rain on Thursday night and it also rained on Saturday night.
Organizers said they consider samples taken from the river 21 and a half hours in advance to allow time for the cultures to develop in the laboratory.
Daily water quality tests measure levels of fecal bacteria, including E. coli. Triathlon World Cup water safety guidelines and a 2006 European Union Directive assign qualitative values to a range of E. coli levels.
According to World Triathlon guidelines, E. coli levels of up to 1,000 colony-forming units per 100 milliliters can be considered “good” and can allow competitions to advance.
World Triathlon, in an email, called the 2006 European Union directive “the most comprehensive guidelines for bathing water,” based on the range of factors it takes into account. Other organizations, including the U.S. Environmental Protection Agency, set a limit of 126 units per 100 milliliters of water and say higher levels are not suitable for recreational use.
When deciding whether events can be held on the river, World Triathlon’s medical committee said it considers water quality analysis, health inspection and the weather forecast.
One day after Wednesday’s competitions in the Seine, data released by World Triathlon showed that a sample taken at 6am on Wednesday at Pont Alexandre III, the bridge where the swimming segment began and ended, showed a level of 249 units. Samples from other points along the course were at similar levels.
Dan Angelescu, founder and CEO of Fluidion, a water monitoring technology company based in Paris and Los Angeles, says the tests have “deficiencies” and “severely underestimate bacteria.”
Fluidion is testing the water several times a day, and Angelescu said, “What we see is that the water quality is not as good as the measurement data the city publishes,” resulting in “an underestimation of the actual risk.”
The company measures “floating” bacteria in the water and adopts a “comprehensive” level that, according to Angelescu, also includes bacteria attached to fecal or sediment particles. He said the comprehensive count provides a more complete picture than the laboratory testing the city is using.
He compared it to looking at a busy road with pedestrians, motorcycles, cars and buses and trying to count all the people. The city’s method, he said, is similar to counting from a helicopter and weighing each person or vehicle equally, because it is not possible to see how many people are inside each car or bus. He says his comprehensive test is more like a police officer stopping each vehicle and counting each person inside the cars and buses to get a complete count.
Angelescu said he discussed these discrepancies with city officials and that they decided to continue with the standard laboratory method they had been using, which complies with regulations. This was a “fair decision in view of the regulations”, he said. “The problem is that the regulations are wrong.”
Rahm of Cornell University said this ultimately “from a public health standpoint. it doesn’t matter if it flows freely or is trapped inside a speck of dirt. It’s going to get into your body one way or another.”
___
Naishadham reported from Washington. AP journalists Jeffrey Schaeffer in Alfortville, France, and Angela Charlton, John Leicester and Ahmed Hatem in Paris contributed.
___
This story originally appeared on ABCNews.go.com read the full story
