Volatile organic matter distribution

Pollutant Distribution. Of particular importance for the aquatic ecosystem is the distribution of volatile substances, eg, gases and volatile organic compounds, between the atmosphere and water, and the sorption of compounds at soHd surfaces, eg, settling suspended matter, biological particles, sediments, and soils (41,42). 

These examples indicate that aggregation and pore-size distribution parameters affect volatilization of petroleum products from a contaminated subsurface. Fine and Yaron (1993) report that kerosene volatilization depends on the type of soil. Tests on four soils with a clay content increasing from 0.3% to 74.4%, and organic matter... 

A study of the Isua organic matter is still in progress (McKirdy Hahn, 1982)s>. Volatile organics have been found to occur chiefly in quartzites and in silicate-rich BIF. Alkane distributions show great variability, even over distances of a... 

PROBABLE FATE photolysis inhibited by presence of oxygen, but possibly the only degradative pathway for highly chlorinated PCB s oxidation not important hydrolysis not important volatilization slow volatilization distributes PCB s globally, but is inhibited by adsorption sorption PCB s are rapidly adsorbed onto solids, especially organic matter, and are often immobilizaed in sediments, but may reenter solution biological processes strong bioaccumulation... 

Each of these oxidation methods which have been used for analysis of dissolved organic matter in sea water have advantages and disadvantages which are summarized in Table IV. Oxidation by the persulfate method appears to be incomplete the photo-oxidation method seems to incompletely oxidize particles the dry oxidation method results in loss of volatile fraction during evaporation and drying steps. However, if proper precautions are followed and sample contamination is prevented, any of these oxidation methods can probably be used with confidence to measure organic carbon in sea water and to study the distribution of DOC in sea-water systems (Fig. 9). 

DHS can significantly affect the environmental behavior of hydrophobic organic compounds and lower the possibility of direct contact of such organic compounds with various solid phases. The rate of chemical degradation, photolysis, volatilization, transfer to sediments/soils, and biological uptake may be different for the fraction of organic pollutant that is bound to DHS. If this is the case, the distribution and total mass of a pollutant in an ecosystem depends, in part, on the extent of humic matter-hydrophobic binding. 

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