U.S. Army scientists have invented a new cleaning product that can decontaminate surfaces tainted with nerve gas, anthrax spores and other nasty substances — and they say it’s environmentally friendly to boot.
Until now, chemical and biological warfare agents such as mustard gas, the nerve agent VX, anthrax spores or radioactive isotopes have each required their own cleaning agents, says research chemist George Wagner of the U.S. Army’s Edgewood Chemical Biological Center in Aberdeen, Md. “There wasn’t really any broad-spectrum decontaminant,” he says. And some of the cleaners that are typically used, such as products containing chlorine bleach, aren’t very environmentally friendly.
So Wagner and his colleagues set out to make a general purpose, greener cleaner. After a decade in the test kitchen, they came up with Decon Green. Not only does Decon Green work — “If the decontaminant comes into contact with the agent, it will destroy it,” says Wagner — but it’s also environmentally friendlier than the disinfectants it is meant to replace.
“Everything just seems to click with this one system,” Wagner says.
The main ingredient in Decon Green is hydrogen peroxide, the familiar disinfectant that makes cuts fizz and a common component of household cleaners and detergents. All but one of the other ingredients, which include the food and drug additives potassium citrate and propylene glycol, are benign enough to be found in everyday cosmetics and foods, Wagner notes. The exception, Triton-X 100, is used as a dispersant in some insecticides.
The reactive oxygen in the hydrogen peroxide provides much of the cleaner’s might. In some instances, such as with the nerve agent VX, it attacks a susceptible phosphorous bond. In other cases the reactive oxygen may substitute one chemical group for another, rendering an agent nontoxic.
Wagner and his colleagues tested their product on several surfaces, they report in the April 7 Industrial & Engineering Chemistry Research, including plain panels of aluminum and panels covered in a chemically resistant paint typically used on military vehicles. Each surface was dosed with a chemical warfare agent such as the nerve agent VX, sulfur mustard gas or a G-nerve agent (the class that includes Sarin). After sitting for an hour, Decon Green was applied.
On the plain aluminum panels “we got stellar marks,” says Wagner. Decon Green reduced contaminant levels to well below what is considered “clean.” But several washes were required to remove the chemicals from the rough surfaces of the painted panels. Testing also revealed that Decon Green kills spores of Bacillus anthracis, or anthrax. It also completely removed a radioactive isotope of cobalt from glass, though it was less successful in clearing the radioactive metal from rubber and steel.
Any addition to the decontamination toolbox is welcome, says Ellen Raber, an environmental decontamination specialist at Lawrence Livermore National Laboratory in California. But she notes that any cleaner needs to be tested on several surfaces. “For chemical warfare agents it makes a really big difference if you are dealing with say, a concrete floor or one covered in linoleum tile.” Outdoors, where surfaces such as soil get sullied, cleanup can be even more problematic.
“We’ve looked at one-size-fits-all decontaminants,” says Raber, cleaners that tackle both chemical and biological agents. Decon Green’s anthrax-fighting powers fit with previous work. But its ability to fully clear chemical criminals will need further testing. “It’s very difficult,” Raber says, “to find something that does both.”
