Buzz
A recent study conducted by scientists from China and the United States revealed yet another compelling reason to avoid urinating in swimming pools, focusing more on the chemical reactions than the social faux pas.
The researchers discovered that when urine mixes with chlorine in the right amounts, it forms two byproducts: trichloramine and cyanogen chloride. The latter can be harmful to the lungs, heart, and nervous system. However, even with chlorine levels much higher than those in most swimming pools, the quantity of these chemicals produced in the study was still within the 'safe' range set by the World Health Organization. In short, you’re unlikely to harm yourself by peeing in the pool. Still, the study cautioned that this chemical reaction could 'adversely affect air and water quality' around the pool. Plus, it's simply unpleasant.
At Ars Technica, editor Casey Johnston was left wondering just how much urine it would take to produce a dangerous level of these chemicals in a pool. After crunching the numbers, Johnston concluded that creating a lethal 'pee pool' would require an overwhelming amount of urine.
To accumulate enough chlorine and uric acid in an Olympic-sized pool to reach a toxic level of cyanogen chloride, Johnston suggests you’d need three million people contributing a full day’s worth of highly concentrated urine to water that's more chlorinated than usual.
“If you could somehow enter that pool without suffocating or drowning in the overwhelming amount of urine,” she writes, “you’d likely end up succumbing to cyanogen chloride poisoning or at least slipping into a deep coma.”
Even in this highly improbable scenario, there’s an issue. The researchers found that much of the chlorine was consumed by the uric acid, meaning you’d need an even higher chlorine concentration—about half a liter of chlorine per liter of water—to create enough cyanogen chloride.
“In the end, we’d need a pool with two parts water to one part chlorine, which would likely burn your eyes out and make your skin peel off,” says Johnston. If three million people manage to urinate into that pool without crushing each other or melting like Nazis opening the Ark of the Covenant, you'd have enough cyanogen chloride to kill (and certainly the world’s worst pool party).
You can read Johnston’s complete thought experiment here.
