Criminals are smuggling billions in US bank notes into Mexico every year, but help could be on the way for border guards.
A machine that can “smell” dollars – like a sniffer dog senses narcotics – is being developed.
For the first time, chemists have captured the unique fragrance of US paper money.
“Money sniffing is an unknown art. No-one had ever tried to find these aromas,” said Dr Joseph Stetter, of KWJ Engineering.
“We found that US currency emits a wide range of volatile organic compounds that make a ‘fingerprint’ we can identify in less than a minute.”
His firm is developing a handheld cash detector for border police, called the Bulk Currency Detection System (BCDS).
In the past fiscal year, US officials seized more than $106m in smuggled cash heading to Mexico – the bulk of it laundered drug money.
But that’s only a whisker of the estimated $39bn that crosses the border undetected every year – hidden in clothing, baggage and vehicles.
Current checks are done by guards with dogs – but training is expensive and time-consuming.
