If you're always worried about whether or not there's urine in the pool before you jump in, worry no longer: There definitely is. Here's how much.
This month, the Journal of the American Chemical Society published a study that estimated there might be as many as 76L of urine in a large swimming pool. To test for pee, scientists measured the concentration of an artificial sweetener that's commonly found in processed food and able to pass through the body unaltered, the Guardian reported.
They tested 250 samples in 31 different pools. Seventy six litres of pee sounds like a lot, but keep in mind, this was in a pool with a volume of about 832,790L. Hot tubs had even larger levels of urine, according to the study. One hotel Jacuzzi they sampled had over three times the amount of sweetener than was found in the worst swimming pool.
Oh, and if you've ever taken comfort in the idea that chlorine probably kills any pool pee, there's more bad news:
However, while urine is sterile, compounds in urine, including urea, ammonia, and creatinine have been found to react with disinfectants to form byproducts known as DBPs that can lead to eye and respiratory irritation. Long-term exposure to the compounds has been linked to asthma in professional swimmers and pool workers.
The good news is that scientists think that, in the future, they might be able to use their sweetener test as a way to measure urine in pools to keep them at a hygienic level. In the meantime, beware of the water and know what you're getting into. For more detail, head to the study and link below.