Have you ever wondered whether there really is such a chemical as a pool urine detector or pool urine indicator dye? Such a dye supposedly clouds the water or produces a color when someone urinates in a swimming pool, as we've seen in movies and on TV. But does a urine indicator really exist?
Is There Truth to the Rumor?
No. There is no chemical which changes color when someone urinates in a swimming pool. There are dyes which could cloud, change color, or produce a color in response to urine, but these chemicals would also be activated by other compounds, producing embarrassing false-positives.
Though there is no such thing as a urine-detecting dye, you can purchase signs that prey upon the misconception that a urine indicator exists. The signs, which warn the pool is being monitored with a chemical "wee alert," are believed to be an effective deterrent against urination in a pool, particularly with adult swimmers.