Dissolved organic matter, water solubility

S solubility in water Kqw- Octanol water partition coefficient Koc Organic matter water partition coefficient K qq Dissolved organic matter - water partition coefficient. Data from Raber and Kogel-Knabner, 1997. 

Dissolved organic matter can be thought of, for simplicity, as soluble organic matter present in soil solution. However, although some workers have measured dissolved organic matter in soil leachates or extracted soil solutions, many use the extract from a 1 2 w/v soil/water extraction... 

The remarkable fact of the presence, in the watery solution, of phosphate of ]imo, usually considered an insoluble compound, is explained by the observation of Wohler, that bone-dust, moistened will, a little water, in the course of a fow days yields to water a considerable quantity of phosphate of lime, and tins solubility rapidly increases with the putrefaction of the gelatine of bones. Hence, wherever earthy phosphates exist with organic matter, water will invariably dissolve a portion, progressively with the decomposition of the organic matter by fermentation. This fact is of the utmost importance to agriculture. 

A basic requirement for uptake of a chemical species from water is bioavailability. Normally uptake is viewed in terms of absorption from true water solution. Biouptake may be severely curtailed for substances with extremely low water solubilities or that are bound to particulate matter. Dissolved organic matter may also bind to substances and limit their biouptake. 

Enhancement of the Water Solubility of Organic Pollutants Such as Pyrene by Dissolved Organic Matter... 

The Stringfellow Superfund site in California poses analytical problems similar to those encountered with most waste sites across the United States and that may be best addressed via LC/MS based methods. Most of the organic compounds in aqueous leachates from this site cannot be characterized by GC/MS based methods. Analysis of Stringfellow bedrock groundwater shows that only 0.78% of the total dissolved organic materials are identifiable via purge and trap analysis (IQ). These are compounds such as acetone, trichloroethylene etc, whose physical properties are ideally suited for GC/MS separation and confirmation. Another 33% of the dissolved organic matter is characterized as "unknown", i.e., not extractable from the aqueous samples under any pH conditions and thus not analyzed via GC. Another 66% is 4-chlorobenzene sulfonic acid (PCBSA), an extremely polar and water soluble compound that is also not suitable for GC analysis. This compound, a waste product from DDT manufacture, is known to occur at this site because of the history of disposal of "sulfuric acid waste from industrial DDT synthesis. 

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