Air Date: Week of November 16, 2007

Poplar trees, also known as aspens or Balm of Gileads, turn a dazzling gold during fall in the Ottawa Valley of Eastern Ontario, Canada. (Photo: Flickr/Valley Vistas)

Genetically engineered trees could be used to absorb toxins in water. Alexandra Gutierrez reports.

Transcript

[EMERGING SCIENCE THEME]

GUTIERREZ: What do you get when you cross a tree with a rabbit? A sponge, apparently. By taking a poplar tree, and inserting an enzyme-producing gene from one of the forest’s faster creatures, scientists at the University of Washington have developed a plant that can rapidly soak up toxins from polluted water. These genetically modified trees can then convert the contaminants into harmless byproducts through a process called “phytoremediation” – a word that literally means “restoring balance through plants.”

Researchers have long seen the potential for plants to do this sort of dirty work, but no naturally occurring species could get the job done. In lab trials, poplar trees without the spliced gene removed only a fraction of pollutants from contaminated water. But the modified plants were able to extract more than 90 percent of toxins, and they did it 100 times faster. What’s more is that these special poplars could dramatically reduce the cost of ground water clean up.

But while these plants may be an effective solution to cleaning up hazardous spills, it may be a while before poplar forests are planted in polluted areas. Federal laws do not permit commercial growing of genetically modified trees, as there is some concern that they could spread into regular forests.

For now, these poplars will stay in the lab or perhaps monitored government sites. But if University of Washington scientists have their way, a forest of poplars could one day mean cleaner streams.