Early in the recent war with Iraq, sandstorms buffeted U.S. troops, choking lungs, guns, and tanks. But it was the potential presence of invisible threats in the air–sandstorm or not–that was most worrisome. At any time or place, it seemed, nerve gas could be lurking. Or anthrax. Or maybe some brand new chemical or biological weapon. Such concerns go beyond the battlefield. Back home, while on “orange alert” during the combat phase of the Iraq war, subway riders wondered how safe, exactly, was the air underground.
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While the tanks waited in the sand this March, scientists at a national meeting of the American Chemical Society in New Orleans paused in front of convention-hall monitors tuned to CNN. They had a special interest in the situation’s complications. “There is this clear and present danger that only analytical chemistry will be able to do something about,” said Anthony Czarnik, a researcher at the Germantown, Md., company Sensors for Medicine and Science.