Question: How do cola pop and toothpaste affect eggs?

Materials:

• 250 mL (1 cup) cola pop
• Drinking glass or open jar (clean jelly, olive, or pickle jars work)
• White shelled egg
• Old toothbrush
• Fluoride toothpaste (check on the tube to be sure it contains fluoride)
• Clock or timer
• Adult helper

Procedure:

1. Place an egg in a glass or jar filled with cola pop. (Make sure you notice the colour of the egg before you put it in the pop.)
2. Leave the egg for 30 minutes to an hour.
3. Remove the egg and notice the brown color which covers the egg.
4. Use a toothbrush and toothpaste to brush the egg back to its original color.

What Happened - and Why?

Sugar (in the pop) combines with bacteria in your mouth to form acid. This acid, along with the extra acid (in the pop as well), attacks the teeth. Over time, these acid attacks weaken tooth enamel, the hard outer covering of your teeth, causing discolouration of your teeth as well as holes in your teeth (called cavities).

The fluoride treatment (your toothpaste) protects the egg's shell from the acid. Your teeth need to be protected from the acids in your month with fluoride too. In order to keep your teeth healthy, you need to keep them clean by brushing with a toothpaste which contains fluoride… and floss your teeth regularly too!