In the end, dirt accumulates, and sometimes rots, especially if ceramics are installed in the bathroom.
To make it easier for you, here are 3 great grout cleaning solutions:
Edible bicarbonate: This product, which is frequently used in making recipes, can also be used to clean ceramic mortar. To use, mix ½ cup (125 ml) of baking soda and enough water to make a paste. Then you apply it to the plaster, let it act and scrub it with a sponge.
Edible vinegar and baking soda: If the cole is very dirty, wash it first with a sponge moistened with white vinegar. Then scrub it with an old toothbrush and baking soda.
Epsom salt: It will work wonders at deep cleaning and disinfecting ceramic grout (an excellent anti-bacterial). Scrub it with a damp cloth, and let it act overnight. The next day, your grout will be cleaner than ever.