Superfund Research Program
Bioremediation of Chlorinated Solvent Compounds: In Situ Remediation Strategies and Predictive Tools for Controlling Contaminated Plumes
Project Leader: John Ferguson
Grant Number: P42ES004696
Funding Period: 1995 - 2006
In the past year, studies of parchloroethylene (PCE) dechlorination in environmental samples from marine sediments and PCE-contaminated groundwater, using enrichments with lactose and PCE, and molecular tools to investigate the presence and concentrations of specific dehalogenators were concluded, and abstracts have been submitted to an international conference on bioremediation of chlorinated organics. Principal findings include detections of most genera of known dehalogenators, but not necessarily linked to dehalogenating activity. Notably, several enrichments, showing the PCE-to-ethene dehalogenator, D. ethenogenes, did not in fact completely dehalogenate PCE. Quantitative PCR and clone libraries have been used to quantitate and identify the dehalogenating bacteria. An vinyl chloride (VC)-degrading culture has been studied using 13-C and 14-C isotopes to identify the metabolic fate of VC and to isolate DNA from organisms growing on VC. Preliminary work has been started on degradation of endocrine disrupting chemicals, examining the hypotheses that these compounds can be degraded cometabolically by microorganisms with non-specific oxygenase enzymes and that degradation can occur at very low concentrations. Two students completed their Master’s theses.