Everyone knows about urine-indicator dye, despite the fact that it has 100 percent never existed
If you pee in the pool, it’ll go blue! There’s a special dye in there, designed to detect urine, and it’ll billow around you in a big, embarrassing, pissy cloud, and everyone will know you’ve done it, and you’ll be hounded out of town as a known pool-piddler.
Everybody knows that, right?
Except it isn’t true. It doesn’t even stand up to any scrutiny as an idea — what chemical specifically detects wee-wee? Would something that would react that dramatically to a dribble of micturition be safe to swim in? And if it happened, and someone was suddenly surrounded by a cerulean aura of widdly-woo, what would the protocol be for lifeguards, pool staff and fellow swimmers? If a pool had to be evacuated every time someone leaked in it, nobody would have ever completed a length. Plus, what would happen next — would they pour in an anti-piss substance that returned it to normal? Would they drain the pool and refill it with untainted water? (Answer: Highlyunlikely).
Despite being clearly nonsense, it still persists as an idea. “I’ve heard many people suggest that there’s a chemical that will react with urine to turn a certain color,” says environmental engineer Ernest R. “Chip” Blatchley III of Purdue University, who has spent a lot of his career studying the chemistry of swimming pools, and has become the media’s go-to figure when discussing people relieving themselves in the shallow end. “But as far as I can tell, it’s a myth. I’m not aware of any chemical that’s added to pools for this purpose.”
“I think everyone who works in the pool trade has been asked about it,” agrees Sue Pace of H2O Swimming Pools Ltd. “But unfortunately, it’s a complete myth.”