10 Surprising Items You Must Never Pour Down the Drain

Omelettes

Eggshell myths persist: some people crush them into tiny shards, believing they will scour pipes clean. In reality, jagged particles snag grease, coffee grounds, and hair, knitting a dense mat that elbows its way into joints and traps standing water.
The calcium in shells does not dissolve quickly, so fragments linger for months. Their abrasive edges also erode older metal pipes, creating pinhole leaks behind walls or under floors. Instead, dry shells in the oven, grind them for garden calcium, or drop them in a compost pile where they enrich soil without endangering plumbing.