Octanol-Water Partition Coefficient (K_OW)

The octanol-water partition coefficient is the ratio of the concentration of a chemical in octanol and in water at equilibrium and at a specified temperature. Octanol is an organic solvent that is used as a surrogate for natural organic matter. This parameter is used in many environmental studies to help determine the fate of chemicals in the environment. An example would be using the coefficient to predict the extent a contaminant will bioaccumulate in fish. The octanol-water partition coefficient has been correlated to water solubility; therefore, the water solubility of a substance can be used to estimate its octanol-water partition coefficient.

More Information

• The search for reliable aqueous solubility (S_W) and octanol-water partition coefficient (K_OW) data for hydrophobic organic compounds--DDT and DDE as a case study : U.S. Geological Survey Water-Resources Investigations Report 01-4201
• How Reliable are Chemical Property Data in the Literature?
• Landmark Book Published on the Fate of Contaminants in the Environment: Partition and Adsorption of Organic Contaminants in Environmental Systems
• Estimating the Environmental Behavior of Inorganic and Organometal Contaminants: Solubilities, Bioaccumulation, and Acute Aquatic Toxicities : Water-Resources Investigations Report 99-4018B, p 447-482
• Assessing the reliability of physico-chemical property data (K_ow , S_w ) for hydrophobic organic compounds: DDT and DDE as a case study, Eganhouse, R.P., Pontolillo J., 2002, SETAC Globe -- A series of articles that appeared in the SETAC Globe Newsletter
• The K_ow Controversy, Renner, Rebecca, 2002, Environmental Science and Technology, v. 36, no. 21, p. 411A-413A.

More Information

• Chiou, C.T., 2002, Partition and adsorption of organic contaminants in environmental systems: New York, John Wiley & Sons, Inc., 257 p.
• Pontolillo, J., and Eganhouse, R.P., 2001, The search for reliable aqueous solubility (SW) and octanol-water partition coefficient (KOW) data for hydrophobic organic compounds--DDT and DDE as a case study: U.S. Geological Survey Water-Resources Investigations Report 01-4201, 51 p.
• International Union of Pure And Applied Chemistry (IUPAC), 1993, Glossary For Chemists Of Terms Used In Toxicology: Pure and Applied Chemistry, v. 65, no. 9, p. 2003-2122 (on-line version posted by the U.S. National Library of Medicine).
• IUPAC, 1996, Glossary of Terms Relating to Pesticides: Pure Applied Chemistry, v. 68, no. 5, p. 1167-1193.

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