Biodegradation of organic contaminants

The most sophisticated model available for predicting biodegradation of organic contaminants in subsurface systems is the biofilm model, presented by Williamson and McCarty149,150 which has been refined over several years by researchers at Stanford University and the University of Illinois/Urbana.151157... 

It cannot remediate metals, although the presence of metals does not appear to limit the biodegradation of organic contaminants. 

Berg, J. D. Eggen, T. (1991)- Enhanced composting for cold-climate biodegradation of organic contamination in soil. In Proceedings, Third EPA Forum on Innovative Hazardous Waste Technologies, Dallas, Texas, June 11-13, pp- 17-36. 

Cerniglia C. E. (1991) Biodegradation of Organic Contaminants in Sediments overview and examples with polycyclic... 

Biodegradation of organic contaminants can be carried out by a single microbial species in pure cultures, but in nature the efforts of a mixture of microbes (a consortium) are usually required. The degradation process ranges from only minor structural changes to the parent molecule, known as primary degradation, to complete conversion to mineral constituents, for example C02 or H20, and termed mineralization ... 

Several studies have examined the effects of rhamnohpid on the biodegradation of organic contaminants especially focussing on various hydrocarbons... 

Yaniga, P. M., and W. Smith. 1984. Aquifer Restoration via Accelerated In-Situ Biodegradation of Organic Contaminants, Ground Water Technology, Chadds Ford, PA. 

Electrokinetic transport is a patented, in situ, commercially available technology for the bioremediation of organic contaminants in aquifer soils and groundwater. The technology involves the application of a direct electrical current across the area to be treated to facilitate the movement of biodegrading bacteria to the site of contamination. 

OXY I is an oxygen injection system for remediation of organics-contaminated groundwater. The oxygen enhances biodegradation of the contaminants, particularly methyl tertiary butyl ether... 

The interaction of bacteria with solid surfaces including soil may have a variety of indirect and direct impacts on the cell (van Loosdrecht et al., 1990). Direct impacts result from changes in microbial membranes (e.g., permeability to various substrates) resulting from a surface interaction. Indirect impacts related to microbial activity are a result of modification of the immediate environment of the cell (e.g., alteration of substrate availability) (Harms Zehnder, 1994). The influences of soil colloids on general microbial processes (Stotzky, 1986) and biodegradation kinetics of organic contaminants (Scow, 1993) have been summarized. However, two areas specifically pertinent to bioremediation will be described. 

Fig. 4.30 Changes in toxicity and mobility of organic contaminants caused by biodegradation and biotransformation. SOM, soil organic matter.

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