Narrator: This is Science Today. Selenium is a problem around the world -- a toxic pollutant that poisons wildlife wherever it collects. And it collects wherever there's heavy industry or agricultural drainage containing pesticides. Biologist Norman Terry says there are several ways to clean up selenium, using plants that absorb it and thus take it out of the ecosystem.

Terry: But perhaps the most interesting aspect that our laboratory's concerned with is the idea of volatilizing selenium.

Narrator: Volatilizing means turning it into a gas. The best way to do that is plant artificial wetlands, or swamps, containing plants that are champion volatilizers.

Terry: We are interested in looking at which plant species in wetlands are able to take up selenium and volatilize it best. And by selecting those species that do take up and volatilize selenium the best, and planting wetlands with those species, we may be able to increase volatilization.

Narrator: Scientists in Terry's lab are also genetically engineering plants to improve the rate at which they absorb selenium and make it harmless. For Science Today, I'm Steve Tokar.