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Native Grasses Destroy Explosives Pollution06-19-09 | News

Native Grasses Destroy Explosives Pollution

Scientists added RDX and TNT to cup-size soil samples and planted switchgrass and Eastern Gamagrass. In just weeks, the toxic chemicals degraded harmlessly into carbon dioxide and water. Initial tests show that the amount of RDX in soil is reduced by 50 percent in a matter of weeks and TNT drops by 95 percent.

TNT contaminates hundreds of sites, from military firing ranges to old production dumps to waterways, and poses a threat to the human nervous system and to the liver and kidneys. It?EUR??,,????'?????<

Mounting evidence has already shown that native grasses could render atrazine harmless. Atrazine is the second most common herbicide used in the U.S. and has been a stubborn pollutant in the nation?EUR??,,????'?????<

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Trinitrotoluene, or TNT, and cyclotrimethylene trinitramine, also called RDX, began creeping into U.S. soil and waterways decades ago, before the manufacturers of explosives came under stricter regulation. Of the 538 locations identified by the Department of Defense with RDX or TNT contamination, 20 are Superfund sites. Congress rejected a Pentagon proposal in 2005 to exempt the military from regulations for pollution from munitions.

To clear a field tainted by those explosives by hauling away the dirt for incineration can run from $100,000 to $1 million an acre. But soil samples doped with explosives and planted with two species of grass caused the explosives to practically disappear. And the cost might run less than $3,000 per acre.