У лондоні стіни обробляють фарбою від сечовипускання у громадських місцях

Westminster City Council are fighting back against people who urinate in public by treating walls with a pee paint that give perpetrators a nasty surprise if they attempt to relieve themselves on it.
The paint creates a water-repellent layer so that urine and other liquid bounce back onto the perpetrator doing the peeing, leaving them soaked.

https://www.westminster.gov.uk/news/council-installs-pee-paint-stop-visitors-urinating-soho