Somewhere around one ten millionth of the water you drink is currently ionized. You better hope it is, anyway. Go ask a chemist what pH actually means. Non c

Somewhere around one ten millionth of the water you drink is currently ionized. You better hope it is, anyway. Go ask a chemist what pH actually means. Non chemists seem surprised to discover that essentially all water is partially ionized all the time. Anyway my point is if 1e-7 of the water you drink technically is not a water molecule at that instant, you can draw graphs of how much of the water you drink has been ionized at some point in the past, which requires a lot more motivation to determine the kinetics than I'm capable of. So, no, essentially none of the water you drink was recently "pee water" or whatever. Yes technically the individual hydrogen and oxygen atoms have quite an extensive ownership history, but the average "age" of an individual water molecule as three atoms with polar covalent non-ionized bonds is surprisingly low in your average glass of tap water. A decent shoulder shrugging "meh" estimate is figure the water molecules in your average pH 7 tap water are about half a day old. Its a lot more than a couple hours and a lot less than a couple months, that's for sure. The "age" of water in the linked article is how long that bucket was isolated and sealed off from the general ecosystem which conceptually is a different kettle of fish. Or kettle of dissolved isotopes in this case.