Trichloroethylene soil pollution

Biotransformation was also strongly indicated as a factor in the degradation of trichloroethylene in a case of soil and groundwater pollution (Milde et al. 1988). The only ethylenes at the point source of pollution were tetrachloroethylene and trichloroethylene however, substantial amounts of known metabolites of these two compounds (dichloroethylene, vinyl chloride, and ethylene) were found at points far from the source. Data from laboratory studies by the same group supported the study authors contention that degradation was due... 

Interest in the bioremediation of chlorinated solvents is widespread. It is impractical to consider all the excellent efforts underway. An example will be given for both a chlorinated alkane and a chlorinated alkene. Both compounds, dichloromethane and trichloroethylene, are commonly used industrial solvents and degreasers that are important soil and water pollutants. 

Chlorinated hydrocarbons are persistent volatile organic compound (VOC) pollutants that infiltrate soil from disposal of dry cleaning fluids, degreasing solvents, food extraction solvents, and paint strippers. Trichloroethylene (TCE) is illustrative of these compounds. 

Since the mid-1980s, electrokinetics (EK) has been widely used as a soil remediation method, especially for low-permeability soils. Numerous studies have demonstrated the effectiveness of EK in the removal of soil contaminants. At first, most investigations focused on metals and only a few targeted relatively soluble organic pollutants, such as gasoline hydrocarbons, phenols, and trichloroethylene. In the case of hydro-phobic organic compounds (HOCs) with low solubility in water, but with a high tendency to be adsorbed onto soil, electrokinetic remediation was previously considered as not applicable because transport by electroosmosis and/or electrophoresis was not to be expected (Acar et aL, 1995 Virkutyte, SiUanpaa, and Latostenmaa, 2002). Therefore, methods to increase the solubility of HOCs had to be coupled with electrokinetic remediation. 

In recent years, several studies have evaluated the benefits of the abovementioned, applying an electric field to enhance the biodegradation process in polluted soil samples with different compounds, aromatic compounds, herbicides, gasoline hydrocarbons, or trichloroethylene [5-8]. With the aim to increase the solubility of the organic-forming complexes and/or increase the electroosmotic flow, the use of chemical or biological surfactants has been assayed in some studies [9, 10]. 

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