Atrazine -- and TNT -- Cleaned Up by Native Grasses

Native grasses like switchgrass and gammagrass have been known to break up the herbicide atrazine, converting it into carbon dioxide.

Atrazine is a popular weed killer used to treat corn and myriad other crops. Unfortunately, because of its extensive usage, it is a common contaminant in the nation's surface water. Degrading it through natural means like grasses is an appealing, inexpensive and environmentally sound solution.

The scientists who had first studied the effects of the grasses on atrazine recently extended their research to include other soil-bound substances with structures similar to atrazine.

They looked into how the grasses interacted with TNT and RDX. TNT is a suspected carcinogen and leads to immune disorders, allergic reactions and birth defects. RDX can cause seizures if inhaled or eaten in large quantities (pdf).

According to the Department of Defense, the two explosives have contaminated 538 sites in the U.S. between them. Twenty of these are Superfund sites.

In lab tests, the grasses rendered the explosives harmless. All that was left of them was carbon dioxide and water.

The next step is to test the grasses outdoors in actual contaminated sites. Sometimes Nature provides the best solutions.

(Photo of native grasses by Chung-Ho Lin, assistant professor of forestry, University of Missouri.)