Biological Oxygen Demand (BOD) is a measure of the amount of dissolved oxygen required by aerobic microorganisms to break down the organic material present in a water sample. It is a commonly used parameter for assessing the level of organic pollution in water bodies.
BOD is usually determined by measuring the dissolved oxygen (DO) concentration in a water sample at the beginning and after a certain incubation period (usually 5 days) at a specific temperature (usually 20°C). The difference between the initial and final DO concentration is used to calculate the amount of oxygen consumed by microorganisms during the incubation period.
BOD is expressed in milligrams of oxygen per liter of water (mg/L), and the higher the BOD value, the greater the amount of organic matter present in the water sample, and the more polluted the water is considered to be. High levels of BOD can lead to a depletion of dissolved oxygen in the water, which can harm aquatic life and make the water unsuitable for drinking and other uses.
