Term: biochemical (biological) oxygen demand (BOD)
https://doi.org/10.1351/goldbook.B00653

Definition:
The amount of oxygen, divided by the volume of the system, taken up through the respiratory activity of microorganisms growing on the organic compounds present in the sample (e.g. water or sludge) when incubated at a specified temperature (usually 20°C) for a fixed period (usually 5 days, BOD5). It is a measure of that organic pollution of water which can be degraded biologically. In practice, it is usually expressed in milligrams O2 per litre.

Related Terms:
1) litre (http://doi.org/10.1351/goldbook.L03594).

Source: PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 148 (https://doi.org/10.1351/pac199264010143)

Citation: 'biochemical (biological) oxygen demand (BOD)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.B00653

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