Eliminate Cryptic Gutter Odors by Cleaning the Mudguard on the Sink
The underside of the splash guard or rubber flaps in the drain that prevent food and other objects from getting back into the sink when you start the disposal is covered on the underside with food scraps that, well, just rot and smell in a place where most people don’t think to clean. … Clean the splash guard with a toothbrush and a degreasing household cleaner. Lift up the edge of the mudguard and use your toothbrush to knock or wipe away debris. Keep walking until you have bypassed all splash protection. Rinse the splash guard with cold water.
Of course, not all sinks have splash protection that you can wash, but if you have a chute in your home then you can make a fair bet.
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