Analytical Technique Could Detect U.S. Currency Smuggling

Tens of billions of dollars of U.S. currency are smuggled from the U.S. to Mexico each year, primarily by illegal-drug dealers, and only a small fraction is found at the border. To reduce currency smuggling and hamper drug gangs, researchers have developed a device that analyzes volatile emissions from paper money. Customs officials now use trained dogs to sniff out hidden money. But dogs find only a small proportion of secreted currency, require expensive training and handling, and aren’t always available. Suiqiong Li and Joseph R. Stetter of KWJ Engineering, in Newark, Calif., described a new system to address this issue, the Bulk Currency Detection System. The researchers found a set of trace aldehydes, furans, and organic acids that is characteristic of U.S. currency. The system uses thermal desorption, solid-phase microextraction, and GC/MS to extract, preconcentrate, and analyze gases from traveler clothing and property and detect the trace substances in seconds or minutes. It could be ready in two to three years, the researchers said.