Caustic Soda Toilet -

This is the closest scientific paper. Urine scale in toilets is mainly and calcium deposits. Caustic soda dissolves organic matter and some scale. Search in Google Scholar: "sodium hydroxide" urine scale toilet removal or "alkaline cleaning" urinal scale

: Caustic soda can soften, warp, or even melt PVC pipes, especially if the solution is too concentrated or remains in the system for an extended period. caustic soda toilet