Sure, peeing in the pool is gross, but most all of us have done it at some point. And as long as no one catches you, it's harmless, right? Well, we don't want to alarm you, but it turns out, that's wrong. Very, very wrong.
As the latest episode of the American Chemical Society's Reactions series explains, urine in the pool, in addition to all the other gross dirt that's on our bodies, can actually have some not-great health effects, including respiratory problems like asthma, and red, stinging eyes.
But first, let's start with a harsh reality, because scientists have shown that public pools contain 30 to 80 mL of urine for every single person swimming in them.
But the problem is that these disinfectants react with pretty much everything on the human body - dirt, sweat, lotion, and even urine. We're just much dirtier than you might think.
When this organic matter interacts with the pool disinfectants, it creates something called disinfection byproducts, or DBPs, which have been linked to some worrying health effects.
Not only are they responsible for the red stinging eyes you get when you're in the pool for a while, but they've been linked to asthma and other respiratory problems, which can be a real issue for professional swimmers.
Showering before you get in the pool can reduce the problem, but the Reactions video explains that up to half the DBPs in a pool are caused by urine... So we really just need to stop letting ourselves go in the water, for our health, if not our self respect.
Check out the video above to find out the chemistry behind your pool, and to find out why common medications might be making the DBP problem worse. We'll never think about that familiar pool smell in the same way again.