Dissolved organic matter compounds

Kan, A.T., Tomson, M.B. (1990) Ground water transport of hydrophobic organic compounds in the presence of dissolved organic matter. Environ. Sci. Technol. 9, 253-263. 

Once a sample of dissolved organic matter has been isolated, it is still seldom in a form that permits simple analysis. In most cases, there are far too many compounds present and some form of fractionation must take place to remove interferences and simplify analytical procedures. 

When released to surface waters, mirex will bind primarily (80-90%) to the dissolved organic matter in the water with a small amount (10-20%) remaining in the dissolved fraction, because mirex is a highly hydrophobic compound (Yin and Hassett 1989). Mean mirex concentrations in sediments, collected at four basins in Lake Ontario between 1982 and 1986, ranged from 30 to 38 pg/kg in three of the basins within the water circulation pattern of the lake. A fourth basin outside the pattern showed much lower concentrations (6.4 pg/kg), indicating that mirex was being transported with the lake water (Oliver et al. 1989). The residence time for mirex in Lake Ontario water was estimated to be 0.3 years. This indicated that mirex was either scavenged by particles or was chemically reactive and, therefore, was rapidly removed from the water column (Arimoto 1989). 

Amal et al., 1992). A sample of dissolved organic matter from a swamp and also two weakly acidic, organic model compounds (polyaspartic and polyacrylic acid) induced a stable sol of hematite (60 nm particles) to form at pH 4.0 and 6.3, respectively (Tiller and O Melia, 1993). 

It is also recognized that the sorption of hydrophobic organic compounds onto dissolved organic matter can significantly increase the solubility of the compounds under aqueous conditions. The importance of solubility in determining the fate of PPCPs will be discussed in Section 3.3.2. Where available, the sorption data can be htted to the Freundlich equation [Eq. (3.17)] to derive sorption parameters for the matrix ... 

Lang, F. Kaupenjohann, M. 2003. Effect of dissolved organic matter on the precipitation and mobility of the lead compound chloropyromorphite in solution. European Journal of Soil Science, 54, 139-147. 

Sorption of Neutral Compounds to Dissolved Organic Matter (DOM)... 

Hence, in principle, we could explain the discrepancies between predicted and observed BAFt values by the reduction of the bioavailability of the compounds caused by sorption to colloidal organic matter present in the culture media. We should note, however, that depending on the nature of the dissolved organic matter (i.e., molecular size distribution, aromaticity, polarity, etc.), the KiDOC value of a compound may vary considerably (see Section 9.4). 

The experimental techniques available to determine AWPCs and their limitations have been discussed by Staudinger and Roberts [2]. These authors also evaluated the effects of pH, compound hydration, compound concentration, cosolvent, cosolute, and salt effects, suspended solids, dissolved organic matter, and surfactants. The experimental data have been compiled by a number of different authors [2-11]. 

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