A new study published in “Environmental Science & Technology Letters” could change how technicians measure urine in a body of water.

Artificial sweeteners can’t be metabolized by humans, so they are excreted in the body’s waste. One such sweetener, acesulfame-K (ACE),is primarily excreted through urine. Researchers have found traces of these chemicals in natural water bodies. Based on information known about ACE, the study hypothesized that testing for the sweetener in pool and spa water would provide a reliable indicator of the amount of urine present. Researchers developed a specialized method to detect and measure ACE in pool and hot tub water samples.

This method was applied to test more than 250 samples collected from 31 pools and hot tubs and more than 90 municipal tap water samples in two Canadian cities. Researchers were able to estimate the urine amount based on ACE numbers. Findings showed an estimated seven gallons of urine in a 110,000-gallon pool and almost 20 gallons in a 220,000-gallon pool.