To clean old toothbrushes, you can soak them in lemon juice, vinegar, bleach or mouthwash. Let them soak for a couple of hours and then rinse thoroughly. This will kill all of the bacteria on the toothbrush itself. After this step, you are ready to use them for many useful purposes.
First of all, toothbrushes are small enough that they are great to use to clean things in your kitchen. Use an old toothbrush to clean a cheese or vegetable grater. The small bristles will easily clean these types of things. Use it to clean your waffle iron in those hard to clean areas.
Toothbrushes are also great to clean some types of food. Think about corn on the cob, and how hard it is to remove the little silk hairs. Next time you make corn on the cob, try cleaning the cobs with a toothbrush. You may be surprised by how easy the hairs will come off. Toothbrushes are also great for cleaning vegetables, such as potatoes. You can scrub the veggies off with the toothbrush, which is an ideal size for small vegetables.
Of course toothbrushes are also ideal for many other purposes. You can literally use a toothbrush to clean any small area in your home. Use it to clean around the faucets in your sinks, or to scrub floor tiles. By keeping your old toothbrushes, you can have the ideal tools for numerous cleaning activities in your home.