Any question answered...

interestingly if the water remembers the toxin that is no longer in it, it's also going to remember being peed out by Julius Cesar as the odds are about the same that you are drinking water that went through his body.

Or, more likely, a dinosaur

We're all drinking dinosaur piss, and that includes you TM because the oldest ice on earth wasn't formed until about 50M years after the dinosaurs checked out.