Cleaning Up

From: University of Washington
Published October 16, 2007 08:21 AM

Scientists ramp up ability of poplar plants to disarm toxic pollutants

-Environmental News Network

Scientists since the early '90s have seen the potential for cleaning up contaminated sites by growing plants able to take up nasty groundwater pollutants through their roots. Then the plants break certain kinds of pollutants into harmless byproducts that the plants either incorporate into their roots, stems and leaves or release into the air.

The problem with plants that are capable of doing this is that the process is slow and halts completely when growth stops in winter. Using plants in this way, a process called phytoremediation, often hasn't made sense given the timetables required by regulatory agencies at remediation sites.

Scientists led by the University of Washington's Sharon Doty, reporting in this week's Proceedings of the National Academy of Sciences, say that genetically engineered poplar plants being grown in a laboratory were able to take as much as 91 percent of trichloroethylene, the most common groundwater contaminant at U.S. Superfund sites, out of a liquid solution. Unaltered plants removed 3 percent. The poplar plants � all cuttings just several inches tall growing in vials � also were able to break down, or metabolize, the pollutant into harmless byproducts at rates 100 times that of the control plants.