By peeing in the pool, you are using up the sterilization capacity already present in the water. The water quality manager then has to increase the rate of chlorination far past what is strictly necessary for bacteria, sweat, skin dust, and sunblock, to account for all the pool-pissers. With over-chlorination and a good particulate filter, some amount of pee in the pool can be absorbed by the system. But if you have the capability to exit the pool and pee in a toilet, that is the civilized and courteous thing to do.
If you recognize NaClO above, you might also know it as bleach. And you might also know that it is very dangerous to mix ammonia with bleach, because it forms respiratory irritants like chloramines and cyanogen chloride. The same types of reactions can occur with the urea in urine.
Also, urine can fertilize algae growth in the pool and screw up your pool pH.
Edit: Wow, what harsh downmodding :) Yes I was wrong and learned something, isn't it still useful to keep my comment here for other's education? I literally heard this "urine is sterile" comment in the last couple of weeks. I stand corrected, thanks!
In normal circumstances getting urine on skin (or drinking small amounts of it for that matter) is not going to cause you any health problem. Urine contains various toxins your liver removed from your bloodstream, so drinking large amounts of it might not be the best idea.
Modern American (and possibly other) cultures have various taboos around cleanliness, including disgust about pee and peeing. But often these are not based on serious health fears.
Don’t pee on wounds though. Urine is not sterile. https://www.sciencenews.org/blog/gory-details/urine-not-ster...
More than 70 percent of the urine samples contained
bacteria, including at least 33 types of bacteria
(at the genus level) in normal urine.
This suggests that 30% were sterile.Where did this myth come from?
And you're only at a medium gray color.