You already know that someone (of course not you) is peeing in the local community pool, but just how much urine can be found in there?
Researchers at the University of Alberta in Canada conducted a study to determine the average amount of urine in community pools, and the answer is you don't want to know.
The researchers tested two different-sized public pools over the course of three works for an artificial sweetener called acesulfame potassium (ACE). The sweetener is widely consumed and makes for "an ideal urinary marker" because it can be detected in varying bodies of water with different pH levels and temperatures, according to the study.
In a pool with 110,000 gallons of water, the researchers found that over the three-week period, swimmers released 7.92 gallons of urine. Technically that's only .000079 percent of the liquid in the pool, if that makes you feel better.
In the bigger pool with 220,000 gallons, they found 19.8 gallons of urine.
You're also going to want to keep your mouth closed while swimming or even hanging out in a hot tub. The researchers tested 250 samples from 31 other pools and hot tubs and found the ACE levels were 570 times higher than tap water.
Experts say that a strong smell of chlorine indicates a pool with a higher level of urine. When your eyes turn red from swimming in a community pool, it's not because of the chlorine.
"When we go swimming and we complain that our eyes are red, it’s because swimmers have peed in the water," Michele Hlavsa, chief of the Center for Disease Control and Prevention’s healthy swimming program, told TODAY in May. "The nitrogen in the urine combines with the chlorine and it forms what’s known as chloramine and it’s actually chloramine that causes the red eyes. It’s chlorine mixed with poop and sweat and a lot of other things we bring into the water with us."
Now that you're surely up for a swim, the Centers for Disease Control and Prevention offers tips like showering before getting into the water, avoiding swallowing the water, steering clear of the pool if you have bowel or diarrhea issues, and finally, of course, don't pee or poop in the water. There's apparently already enough other people doing that.
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