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While one in five Americans admits to peeing in the pool, according to a survey conducted by the Water Quality and Health Council, if former U.S. National Team swimmer Carly Geehr is to be believed that rate of underwater urination skyrockets among Olympians.

"Nearly 100 percent of elite competitive swimmers pee in the pool. Regularly. Some deny it, some proudly embrace it, but everyone does," Geehr said on the website Quora. Indeed, record-breaking Olympic swimmer Michael Phelps admits to regularly relieving himself while swimming.

"I'm sure I've swum directly behind people who were just letting it all out," Geehr added in the statement.

When mere mortals cop to pool peeing, one of the reasons it seems so offensive is that it violates a code of behavior -- to relieve oneself in the pool, around others, is truly antisocial. But given that the practice seems acceptable in the competitive swimming community ("Yeah. Peeing in the pool is commonplace. It doesn't even cross our minds," adds All-American Swimmer Dave Ford on the Quora conversation), is it really harmful?

Yes, according to epidemiologists. In a previous interview with HuffPost Healthy Living, Michele Hlavsa, an epidemiologist and chief of Healthy Swimming and Waterborne Disease Prevention at the Centers for Disease Control and Prevention, explained that pool pee really can cause a sanitation problem.

The nitrogen in urine binds to the chlorine present in pools -- the sanitizing chemical used to destroy pathogens like E. coli, salmonella and other bacteria people carry -- to create a different chemical, chloramine. That's a problem for two reasons. First, binding to the chlorine ties it up, so it becomes a less effective disinfectant. And that leaves way for dangerous bacteria to survive longer in each pool, which can spread common illnesses like diarrhea from chryptospiridium.

What's more, chloramine is irritating to many people, causing respiratory irritation, coughing and stinging, red eyes. Chloramine also creates a strong smell that many of us associate simply with pools. If you smell that "pool smell," according to Hlavsa, you're most likely smelling chloramine rather than chlorine. (It's important to note that the chloramine smell doesn't necessarily indicate that urine is in the pool -- sweat and some personal care projects also contain nitrogen. That's why many pools require a quick rinse before you dive in.)

Next time you're tempted to relieve yourself in the pool, think of your companions -- or competitors.

For more pool hazards and solutions, read on: