It’s a question we all think, but no one wants to ask: How much urine is really in a public swimming pool? In a new study, a team of scientists in Canada recently tested the water in 31 different public pools and hottubs, and their results aren’t for the faint of heart.

The study specifically looked at the amount of artificial sweeteners found in public pools, which they hypothesized could be an indication of urine in the water. This is because these sugars pass through the body undigested and exit in urine. All of the pools and tubs where samples were taken had trace amounts of artificial sweeteners in their water. According to the study, this was enough to conclude that all the pools surveyed had at least some human urine in it. One swimming pool, which was about a third the size of an Olympic-sized pool, had an astonishing 75 liters of urine, while a smaller pool had 30 liters, The Independent reported.

Read: The Dangerous Chemicals That May Form When Urine Mixes With Chlorine

“Even though no one would admit to peeing in a pool, obviously somebody has to be doing it,” said one of the researchers, Lindsay Blackstock, The Independent reported.

This isn’t very surprising, seeing that as many as 19 percent of adults openly admit to peeing in pools (and there’s no telling how many practice this behavior in privacy.)

Okay, so there’s urine in the pool, is it time to worry? Maybe. Chlorine added to pools help to prevent microorganisms from growing in the water. However, when chlorine reacts with the urea in urine it creates trichloramine, a compound that can cause respiratory and eye irritation, Reactions reported.

“Trichloramine in indoor swimming facilities can lead to eye and respiratory irritation and has been linked to occupational asthma,” the researchers told The Independent.

In addition, a 2014 study found that when uric acid, another byproduct of urine, combines with chlorine, it creates something called cyanogen chloride. This gas could be harmful to the central nervous system, heart, and lungs when inhaled.

In addition, it’s not just the chemical reactions between urine and chlorine that can be harmful. Other contaminants in urine, such as ammonia, amino acids, and creatine, are also not good for human health. So, all in all, if you can make it to a toilet to do your business, please do, for the sake of our communal health!

Source: Blackstock LKJ, Wang W, Jaeger BT, Li XF. Sweetened Swimming Pools and Hot Tubs. Environmental Letter, Science and Technology . 2017

See Also:

Is Peeing In The Swimming Pool OK? How Cleaning Products React With Urine

Swimming Benefits: 8 Reasons Why The Sport Good For You

Published by Medicaldaily.com