A unique study from Canadian researchers dove into looking for a way to tell if there is urine in public swimming pools. And in what may be rather unsurprising results, there is a lot of pee in those blue waters – more than anyone would be comfortable with.
The idea that the researchers came up with was pretty simple, and rather ingenuous: an artificial sweetener called acesulfame potassium(ACE), which is an ingredient in many common consumer products, Huffington Post reports.
The human body is unable to break down acesulfame potassium, which means it is excreted in urine but is still detectable in bodies of water, even in different temperatures and pH levels. This includes chlorinated water.
The researchers tracked activity in two public pools for three weeks for the presence of ACE. One swimming pool had 110,000 gallons of water, while the other held 220,000 gallons.
When ACE levels were measured, the research team found that in a three-week period, people put in at least 7.92 gallons of urine in the smaller pool, and close to 20 gallons into the bigger one.
The researchers also measured 250 water samples from 31 more pools and hot tubs, and found that ACE levels were up to 570 times more than the amount of pee present in tap water.
Urine contains nitrogenous compounds like urea, ammonia, amino acids and creatinine, the study says. These compounds can cause eye and respiratory problems when combined with disinfectants. People who spend a lot of time in swimming pools, like professional swimmers and pool workers, have reported developing asthma that has been linked to the time they spend in the pool.
Lindsay Blackstock, lead researcher on the study from the University of Alberta, says there should be more public awareness and education on appropriate swimming hygiene practices.
“We recommend that all pool users should rinse off excess personal care products in the provided showers before entering public pools,” Blackstock says. “Additionally, we should all be considerate of others and make sure to exit the pool to use the restroom.”
The study was published in Environmental Science and Technology Letters.