Biological Oxygen Demand (or BOD):
- The amount of oxygen required by the microorganism to digest all of the organic materials in the water is referred to as BOD (Biological Oxygen Demand).
- Aerobic bacteria are engaged in the breakdown of organic materials. It decomposes organic materials in water by using oxygen.
- The presence of less organic matter in water implies that it is less contaminated, but greater BOD indicates that the water is more polluted due to the presence of more organic matter.
- As a result, it serves as an indicator of the level of pollution in the water. However, it only tells the contamination level of water based on organic materials.