What does biochemical oxygen demand (BOD) measure?

Biochemical oxygen demand (BOD) specifically measures the amount of oxygen that microorganisms require to decompose organic matter in a water sample over a specified period, typically five days. This measurement is crucial for assessing the level of organic pollution in water, as it indicates how much oxygen will be consumed by bacteria as they break down this material.

High BOD values suggest that there is a significant amount of organic material present, which can lead to oxygen depletion in the water, negatively affecting aquatic life. Conversely, low BOD values indicate cleaner water with less organic matter, which is favorable for maintaining healthy aquatic ecosystems. This focus on microbial activity and its oxygen consumption makes BOD an essential parameter in evaluating water quality and the effectiveness of wastewater treatment processes.