It's one of those truths of summer you probably don't like dwelling on, but any public pool probably contains some urine. Now a team of chemists at the University of Alberta can quantify exactly how much.
Lead researcher Xing-Fang Li and her colleagues report they can determine about how much pee is in a pool by measuring the artificial sweeteners found in most people's urine. Certain sweeteners can be a good proxy for urine, she told NPR, because they're designed to "go right through you" and don't break down readily in pool water.
By collecting samples of pool water from hotels and recreation centers in two Canadian cities and testing for a sweetener called acesulfame potassium, commonly found in many foods, Li and her team have determined that a 220,000-gallon commercial-size swimming pool contains almost 20 gallons of urine. In a residential pool that means about 2 gallons for a 20-by-40 foot, 5-foot deep pool.
So . . . yuck!
It's also a potential health hazard since chlorine can react with urine to form a host of potentially toxic compounds, including cyanogen chloride, a chemical warfare agent, and nitrosamines, which can cause cancer. You'll be relieved to know there isn't enough evidence to suggest nitrosamine levels in pools are enough to increase the risk of cancer.
One coping strategy? Follow basic pool rules. Shower before entering, as this can remove most of the bodily fluids that react with chlorine. And hold it until you get out of the pool.
