Swimmers could be surrounded by 50 gallons of urine, study finds

Ace is an artificial sweetener that is widely consumed in sodas, baked goods and other foods, and passes straight through the digestive tract and into human urine.

Another 30 litres of urine was detected in the second pool, which was about half the size of the first.

A new test has been developed which can estimate how much urine is in a large volume of water.

The team estimated that swimmers released more than 32 litres of urine - enough to fill a medium-size trash bin - in a 500,000-litre pool in one instance.

Out of the 31 pools and hot tubs tested, urine was found in every single one.

It found concentrations of ACE in the pools and tubs, which were not named, that were up to 570-fold greater than in normal tap water.

It's a question that's crossed all of our minds while visiting a public swimming pool - are people pissing in the water?

Armed with this new knowledge, she and her team got to measuring and concluded: "Overall our study provides additional evidence that people are indeed urinating in public pools and hot tubs".

In order to do this, we need improved understanding of pool chemistry. "Additionally, we should all be considerate of others and make sure to exit the pool to use the restroom".

Although the researchers were unable to confirm exactly what fraction of visitors were choosing to quietly relieve themselves in the water rather than making the shivery trip to the changing rooms, the results suggest that the urine content was being topped up several times each day.

"Exposure to volatile DBPs... in indoor swimming facilities can lead to eye and respiratory irritation and has been linked to occupational asthma" in professional swimmers and pool workers, the authors write in Sweetened Swimming Pools and Hot Tubs, published American journal, Environmental Science & Technology Letters. "Chlorine kills it, so it's not bad".

Even though urine only generally contains a low level of bacteria, its nitrogenous organics can react with the chlorine in pools to create disinfection byproducts (DBPs), which can be unsafe for swimmers.

'I think everybody pees in the pool, ' he said.

  • Lila Blake