Nick Fetty | February 17, 2015
A team of researchers from the University of Iowa’s civil and environmental engineering department have discovered a way to remove harmful PCB’s from the soil using a native prairie grass.
The findings were published in a report in the journal Ecological Engineering, authored by professor Jerry Schnoor and associate professor Tim Mattes. Yi Liang, Richard Meggo, and Dingfei Hufrom from the civil and environmental engineering department also worked on the project.
During lab experiments, the researchers found that switchgrass (panicum virgatum) was successful in removing up to 40 percent PCB’s from contaminated soil. When coupled with a PCB-oxidizing organism, the PCB removal rate was as high as 47 percent.
“The possibility of synergistic interactions between the switchgrass and the bioaugmented PCB-degrading bacteria suggests that employing both plants and bacteria in PCB remediation strategies holds promise for enhanced removal of these recalcitrant compounds from contaminated sites,” Mattes said in an interview with the UI’s news service, Iowa Now.
PCB’s – or polychlorinated biphenyls – are toxic chemical compounds once found in coolant fluids and other industrial products. PCB’s were banned by U.S. Congress in 1979 but remain in soil, water, and other parts of the atmosphere at varying levels.
Switchgrass has also been used as a biomass fuel source. The Chariton Valley Biomass Project is an Iowa-based project consisting private entities as well as the U.S. Department of Energy “seeking to demonstrate the technical and commercial feasibility of producing power from locally-grown and harvested renewable fuel resources.”
Funding for the UI research was provided by the National Institute of Environmental Health Sciences Superfund Research Program. The UI’s Comment Center for Biocatalysis and Bioprocessing provided the funding for Yiang’s fellowship.