The future is looking cleaner and greener thanks to the efforts of a group of UW scientists.

Researchers have increased poplar trees' ability to neutralize hazardous pollutants in soil and air 100 times its natural capability.

The group's breakthrough, detailed in a paper published Monday, is regarded as a first in the use of plants to clean up pollutants from the environment, or phytoremediation.

Plants can naturally clean the soil and air of substances harmful to humans by absorbing them into their roots, stems and leaves. Once inside, plants break the pollutants down into harmless byproducts. Phytoremediation is, however, still not widely utilized by regulatory agencies for decontamination.

"Compared to conventional methods, it is often too slow, is only seasonally effective or removes only small amounts of pollutant from the environment," said Sharon Doty, professor of forest resources and leader of the group. "Our attention has focused on ways to enhance the phytoremediation potential of plants using transgenic methods."

The UW group found success in increasing the trees' cleansing ability by inserting a gene ordinarily found in rabbits into the poplars' genetic material. The unaltered gene functions to pump up the trees production of the enzyme responsible for breaking down cancer-causing pollutants such as trichloroethylene, benzene and chloroform.

"Genetic code is the same between bacteria, plants, animals and all life as we know it," Doty said. "Since plants and animals can read the same language, the rabbit gene can be read by the plant cell so it makes the proper enzyme."

The transgenic poplars developed by Doty's group were able to remove up to 91 percent of pollutants from a liquid solution, 100 times greater and 53 times faster than unmodified poplars.

Despite their success, some scientists have expressed reservations.

"The idea of the research is commendable," said Doug Gurian-Sherman, a senior scientist with the Union of Concerned Scientists. "However, there are some hard questions left to be answered before these plants can be used widely for their intended purpose."

Some scientists worry the trees will spread the added gene into wild poplars. Little is known of the transgenic trees' effects on insects and animals that feed on them.

"We need to make sure that in solving one problem, we don't create others," Gurian-Sherman said. "Scientists need to think creatively about how this can be done safely."

Doty acknowledged these anxieties, stating that further research will sort out residual questions. She also cited a strict regulatory framework instituted by the US: Department of Agriculture, the agency responsible for regulating biotechnology.

"It is our hope that by developing trees that can remove carcinogens from the water and air in a fast and economical way, people will be more likely to use them than abandon the property," Doty said. "There is much research left to be done before we reach that stage."

[Reach reporter Brian Smoliak at news@thedaily.washington.edu.]