New invention to detect caches of cash

Soon people will be looking for ways to mask it.

Drug traffickers who ship profits abroad in suitcases of cash are not apt to be thrilled with some new inventions being developed by federal scientists at the Idaho National Laboratory.

One sniffs the air for currency's chemical signature -- it can pick up a stack of bills from about 10 feet away. Another device beams electrons through packages or luggage to detect trace metals in the green ink.

And a third project, not yet started, would actually scan serial numbers of individual bills into a database.

The lab's lead scientist, Keith Daum, says the goal is to intercept cash used in illegal drug or terrorism transactions.

"When Joe the Druggie gets his $20 from an ATM and spends it on a (drug) pickup, and the money is later traced to a drug seller -- to me, that's evidence," Daum said in an interview.

It's unclear whether the legal system would view such evidence as admissible, and privacy advocates fear such inventions would infringe on civil liberties if adopted.

The cash sniffer is actually a gas chromatograph about the size of a cordless hand vacuum.

Here's how it works: Take a crisp $20 bill out of your wallet and put it up to your nose. That sweet, slightly acidic aroma is actually microscopic molecules of ink and paper landing on the nerve receptors inside your nose.

The device works in nearly the same way, but with much higher sensitivity. Airborne molecules land on a sensor. If enough molecules are detected, the device emits an alert.

Daum said a trained dog can do the same thing -- even better -- but not consistently and not over a long period.

The second device is simply called the "physics-based" detector. About the size of a small airport X-ray scanner, it scans an interior space for elemental metals used in the green ink. Radioactive rays strike the metals and turn into gamma rays, which are then measured by the machine. The more gamma rays detected, the higher the volume of cash bills.

Although the test machine is small, Daum said it could be built large enough to scan a shipping container.

The two machines were developed with funding from U.S. Immigration and Customs Enforcement agency. Its parent, the Department of Homeland Security, is currently analyzing them and submitting them to additional testing.

Of course, carrying cash -- even large amounts of it -- is not illegal; though there is a limit of $10,000 in cash anyone may carry in or out of the United States.

Still, intercepting large sums of money would at least put a dent in the drug trade, argued lab spokesman Ethan Huffman.

"Money is always the incentive to bring drugs across the borders," Huffman said. "If we can devise solutions to aid customs and border patrols in stopping that, then that limits it."

The third project, a relatively new device, is on loan to the INL from another agency. It looks like a typical bill counter used by banks to count stacks of cash. But on the back of the machine, an add-on box about the size of a file folder reads and stores the serial numbers of every bill it counts.

The machine is of little strategic value by itself. But if it was distributed worldwide, and if there was a database of serial numbers, it would become possible to trace money across the globe.

That worries people like Melissa Ngo of the Washington-based Electronic Privacy Information Center.

"This is just another step toward a complete lack of anonymity," Ngo said.

"There are many reasons people wouldn't want information about where they spend their money," Ngo said. "From stopping mass marketers to people thinking it's nobody's business what books or CDs they buy."

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