Deodorizing a Stinky Sink For really terrible sink smells, first get a green scrubby and scrub the sides and especially the drain area which is ofter neglected and builds up quickly.
Run the hot water and spray the sides and drain thoroughly. For stubborn smells, you can pour a 50/50 mix of bleach and hot water down the drain and let it sit for 5 minutes or more before running additional clean hot water down the sink.
Bleach will actually liquefy mold and mildew that's built up in the pipes. If you notice a sewer smell emanating from the sink itself, you can pour some commercial cleaner. If this doesn’t work, there is a more serious problem than simple grime and a professional plumber can help diagnose the problem