Plant Microbe Match

University of Minnesota researchers pair plants with microbes to remove arsenic from contaminated soils.

by MaiLei Meyers

The contamination of soil with heavy metals like arsenic is a lasting legacy of the industrial age. In fact, the World Health Organization has identified arsenic as one of 10 chemicals of major concern. Minnesota, like other industrial states, had its fair share of arsenic-contaminated land, including the South Minneapolis Contamination Superfund and Perham Arsenic Superfund sites. Cleanup efforts traditionally involve the removal of contaminated soil and its long-term storage in a designated landfill. University of Minnesota scientists Michael Sadowsky and Cara Santelli are working on a sustainable alternative using hyperaccumulator plants that remove toxic metals from soil and incorporate them into plant tissue.  

“You can harvest and burn plants to collect the metal from their contents. In environmental clean-up, it’s called phytoremediation,” explains Michael Sadowsky, Director of the University of Minnesota’s BioTechnology Institute and an expert on plant-microbe interactions. Santelli, his partner on the project, is a geomicrobiologist in the Department of Earth Sciences. Together, they plan to augment the natural uptake of toxic metal using a class of soil microbe called rhizobacteria, which form symbiotic relationships with plants.

The research began in the greenhouse with a study of two plants capable of accumulating metals at a different rate. Using soil from EPA Superfund sites, the labs will measure the amount of metal absorbed by the plants when paired with microbes capable of immobilizing toxic metals in the soil or making them more accessible for natural uptake.

With that knowledge in hand, Santelli and Sadowsky will move on to local contaminated sites and test their findings in the field.

The Minnesota Pollution Control Agency and the Department of Agriculture granted access to Superfund sites during the pilot project funded with a seed grant from the MnDRIVE Environment initiative. The UMN team has partnered with Geosyntec, a national consulting firm with expertise in environmental engineering and the cleanup of contaminated metals. Geosyntec will assist in scaling successful field trials.

Seed Grant Funding

Projects like Sadowsky’s current phytoremediation research could help increase visibility for seed funding programs like MnDrive.  “Without seed funding, the ability to generate foundational data for federal funding is limited,” says Sadowsky, who also serves as Co-Director of MnDRIVE’s bioremediation initiative.

In addition to seed funding, MnDRIVE promotes collaboration with local industry and government agencies. “We’re providing research that can help drive Minnesota’s economy and protect its environmental legacy. Since its inception five years ago, MnDRIVE has played a crucial role in developing new technologies and promoting collaboration between research institutions, industry, and government.”

MaiLei Meyers is a double major in Film and Journalism with an emphasis in Strategic Communications and Public Relations at the University of Minnesota’s College of Liberal Arts and an intern in the BioTechnology Institute’s Science Communications Training Program.