Difference Between Fluoridation and Defluoridation

The key difference between fluoridation and defluoridation is that fluoridation is the process of increasing the fluoride content, whereas defluoridation is the process of decreasing the fluoride content in drinking water.

Both fluoridation and defluoridation are very important processes regarding the quality control of municipal water we use as drinking water. Defluoridation is the opposite process of fluoridation, and both these processes can be helpful in different situations. Thus, it is important to know the exact difference between fluoridation and defluoridation.

CONTENTS

1. Overview and Key Difference
2. What is Fluoridation 
3. What is Defluoridation
4. Side by Side Comparison – Fluoridation vs Defluoridation in Tabular Form
5. Summary

What is Fluoridation?

Fluoridation is the process of increasing the fluoride level in drinking water. It is the controlled adjustment of the fluoride level to maintain the appropriate fluoride levels in the water. This is very important to prevent tooth decay. The fluoride in water can prevent the formation of tooth cavities. In this process, a chemical compound containing fluoride ions is added to drinking water. However, fluoridation does not change the colour, smell or taste of water

Figure 01: Fluoridation does not Change the Colour, Smell or Taste of Water

Earlier, people used sodium fluoride for this purpose. However, it is an expensive chemical compound. Today, the compound USA uses for this process is fluorosilicic acid, which is inexpensive. Another compound we can use for fluoridation is sodium fluorosilicate.

What is Defluoridation?

Defluoridation is the process of decreasing the fluoride level in drinking water. In groundwater, fluoride ion is very abundant. Further, this ion is present in high amounts in groundwater compared to surface water. It is due to the leaching of minerals. Since excessive fluoride ion content in drinking water can cause different health issues, defluoridation is an important process. The health problems that occur due this high levels of fluoride include dental fluorosis and skeletal fluorosis.

Figure 02: Mild Dental Fluorosis

Although there are different techniques for defluoridation, there are a few limitations as well. The major problem is the high cost. Sometimes, these processes may release even contaminants to the water. Besides, the major techniques we can use for defluoridation include adsorption, precipitation, ion exchange, membrane processes, etc. All these processes are very effective in removing fluoride ion, but the disposal of fluoride-containing sludge is problematic.

What is the Difference Between Fluoridation and Defluoridation?

Defluoridation is the opposite process of fluoridation. The key difference between fluoridation and defluoridation is that fluoridation is the process of increasing the fluoride content, whereas defluoridation is the process of decreasing the fluoride content in drinking water. When considering the techniques of these processes, fluoridation can be done via the addition of chemical compounds such as sodium fluoride, fluorosilicic acid and sodium fluorosilicate and defluoridation can be done via adsorption, precipitation, ion exchange, membrane processes, etc.

The following infographic summarizes the difference between fluoridation and defluoridation.

Summary – Fluoridation vs Defluoridation

Both fluoridation and defluoridation are very important water-treating processes. Defluoridation is the opposite process of fluoridation. The key difference between fluoridation and defluoridation is that fluoridation is the process of increasing the fluoride content, whereas defluoridation is the process of decreasing the fluoride content in drinking water.