Imagine how many urinary tracts “freshwater” has run through from dinosaurs onward, lol.
The thought has occurred to me. But molecularly speaking (look, I made up a phrase), water is still just water. Once separated from the impurities, it’s just that. The ISS has a water reclamation system, by the way. Although you’re technically drinking most of your own pee, water is still just water. Doesn’t matter where it came from since that has no bearing on its chemical makeup.