You can toss bath sponges in the laundry weekly to clean and sanitize them.
-Simply wash as normal with laundry detergent.
-Can be placed in Mesh Laundry Bag.
-Only do this in a Cold water or Warm water wash. NOT hot water.
-Do NOT dry them in the dryer. As this can melt them.
-Replace after 3-4 Weeks or as needed.