An unfakeable test for cocaine use that only requires a single fingerprint has been developed by scientists.

It is the first of its kind to test for ingestion of the drug, and is sufficiently developed that its creators expect it to be miniaturised into a portable device and in the hands of law enforcement agencies within ten years.

By using mass spectrometry, the test is able to detect the presence of chemicals excreted as cocaine metabolises in the body, providing immediate confirmation of a suspect’s cocaine use.

Such a device would be a revolution for law enforcement, as it would enable police, prison officers and other agents to establish if a person had taken the drug at the scene, without the need for invasive blood or urine tests.

It would also remove the need for specialists and safe storage and disposal of bodily fluids, reducing costs and rapidly speeding up the process.

It is likely become a commonly used device, akin to the breathalyser, that police use during standard stop-and-searches and raids.

The test, which was developed by scientists from the University of Surrey with support from researchers from the Netherlands Forensic Institute, the UK’s National Physical Laboratory, King’s College London and Sheffield Hallam University, is notable for ability to test for ingestion of cocaine, rather than just skin contact.

“When someone has taken cocaine, they excrete traces of benzoylecgonine and methylecgonine as they metabolise the drug, and these chemical indicators are present in fingerprint residue,” explained study lead author Dr Melanie Bailey, from the University of Surrey.

“For our part of the investigations, we sprayed a beam of solvent onto the fingerprint slide (a technique known as Desorption Electrospray Ionisation, or DESI) to determine if these substances were present. DESI has been used for a number of forensic applications, but no other studies have shown it to demonstrate drug use.”

The scientists verified the test’s efficacy by comparing its results to standard saliva tests, thus demonstrating that it would be reliable enough to use in real-world situations.

As it tests using a fingerprint, the device could also simultaneously verify the subject’s identify, meaning it would be – at least in theory – impossible to fake.

“The beauty of this method is that, not only is it non-invasive and more hygienic than testing blood or saliva, it can’t be faked,” said Bailey.

“By the very nature of the test, the identity of the subject is captured within the fingerprint ridge detail itself.”

Detailed in research published today in the journal Analyst, the test only requires miniaturisation before it can be used by law enforcement. And due to advances in this area, the researchers are confident this will be a quick process.

“We are only bound by the size of the current technology. Companies are already working on miniaturised mass spectrometers, and in the future portable fingerprint drugs tests could be deployed,” added Bailey.

“This will help to protect the public and indeed provide a much safer test for drug users.”

However, the public reaction to the device remains to be seen.

In a world where increasing police powers and control are a genuine concern, a fingerprint scanning device of this type could be met with considerable suspicion and resistance.