We are developing bioremediation/phytoremediation technologies for heavy metals, radionuclides, and organic pollutants. Organic pollutants such as polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and dibenzofurans, and chlorinated compounds are ubiquitous originating from incomplete combustion of fuels and forest and grass fires and as industrial chemicals, and petroleum inputs.

Microorganisms native to soils and sediments have shown the potential for degradation of a wide variety of organic pollutants (bioremediation) into benign compounds. Bioremediation is cost effective, noninvasive leaving the ecosystem intact and a permanent solution providing for complete mineralization of the pollutant.

Compared to the conventional chemical/physical processes of remediation involving excavation, dredging etc., it is critical for sustaining the environment. Heavy metals such as cadmium, lead, copper, zinc, arsenic, chromium although essential to microbes and plants in trace amounts are toxic at higher concentrations. Microbes using redox processes can convert these trace pollutants to their non-toxic forms.

Radionuclides (actinides) such as uranium, techentium, neptunium contaminate soils, and sediments at radionuclide milling sites, subsurface environs of former US weapons complexes and at many DOE sites and are of even greater concern than the heavy metals due to their long half lives of the order of billions of years.  We are developing strategies based on radionuclide/heavy metal removal via phytoremediation and immobilization of radionuclides via reduction by dissimilatory metal reducing bacteria.