Common Artificial Sweetener Used to Measure Amount of Pee in Swimming Pools -- Find Out How Much!

A team of scientists has developed a new method of determining the amount of urine being discreetly added into swimming pools.

The new technique, described in a paper published in the journal Environmental Science and Technology Letters, utilized an artificial sweetener that can be commonly found in processed foods, like sodas and baked goods.

The sweetener, known as acesulfame potassium (ACE), is widely consumed, chemically stable and can't be processed by the body, which means it passes right through the digestive tract and into the consumer's urine.

"In general, artificial sweeteners have unique characteristics: they are highly stable, consumed widely by the public, are not metabolized by the human body, and only enter the environment from human waste.," said Lindsay Blackstock, a graduate student at the University of Alberta and lead author of the study, in an interview with Research Gate. "This makes artificial sweeteners an effective indicator of human waste impact in environmental water bodies."

Using ACE as an indicator, the researchers developed a rapid, high-throughput analytical technique to test over 250 water samples taken from 31 actively used swimming pools and hot tubs in two Canadian cities. The researchers also used the new analytical technique to test the concentration of ACE in more than 90 samples of clean tap waters.

The researchers found that the concentration of ACE in pools and hot tubs is up to 570 times higher than the levels found in tap water, ranging from 30 to 7,110 nanograms per liter of water. Based on the ACE concentration in the water, the researchers estimated that a 110,000-gallon swimming pool has more than 7 gallons of urine. A swimming pool about a third of Olympic-sized pool, which holds around 220,000 gallons, has nearly 20 gallons of urine.

Most people admit that they have urinated in the pool. These people argue that the chlorine in the pools could clean the urine. However, some chemicals in pee, including urea, ammonia, amino acids and creatinine, could react with the chlorine to create disinfection byproduct. These byproducts, such as trichloramine, can cause eye irritation and respiratory problems.