Title: dissolved organic carbon
Long Title: IUPAC Gold Book - dissolved organic carbon
DOI: 10.1351/goldbook.14595
Status: current

Definition
Amount concentration of carbon found dissolved in water samples from aquatic systems, measured as total elemental carbon.

Notes
1) The "dissolved" fraction of organic carbon is an operational classification. Operationally, DOC is defined as the organic matter that is able to pass through a defined filter (filters generally range in size between \(\pu{0.7 \upmu m}\) and \(\pu{0.22 \upmu m}\)). Conversely, particulate organic carbon (POC) in water is that carbon that is too large and is filtered out of a sample.
2) The DOC in marine and freshwater systems is part of the greatest cycled reservoir of organic matter on Earth and consists mostly of humic substances.
3) DOC is important in the transport and bioavailability of pollutants in aquatic systems.
4) Metals may form strong complexes with DOC, increasing metal solubility and concentration in water, while also reducing metal bioavailability.

Related Terms
- dissolved organic matter: https://goldbook.iupac.org//terms/view/14597
- pollutants: https://goldbook.iupac.org//terms/view/14928

Source
- PAC, 2009, 81, 829. 'Glossary of terms used in ecotoxicology (IUPAC Recommendations 2009)' on page 868 (https://doi.org/10.1351/PAC-REC-08-07-09)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/14595/html
- json: https://goldbook.iupac.org/terms/view/14595/json
- xml: https://goldbook.iupac.org/terms/view/14595/xml

Citation: Citation: 'dissolved organic carbon' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.14595
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Accessed: 2026-04-18T03:37:55+00:00