Drug dealers have one less plea to make in court after new research shows virtually every bank note in circulation in Britain is contaminated with cocaine - and to roughly the same degree, writes Dick Ahlstrom.
The finding will make it more difficult for drug dealers to plead that notes found in a particular area are more likely to be highly contaminated by drugs. The study and how it helps counter drug dealers was presented yesterday to the BA festival of science.
Gavin Lloyd, Karl Ebejer and colleagues from the University of Bristol and Mass Spec Analytical Ltd described how all bank notes, even new ones that have just entered the cash system, were contaminated by drugs, findings that put a whole new meaning on the term "drug money".
They used mass spectrometry to analyse thousands of £10 and £20 notes taken from areas across Britain. "Pretty much all the bank notes were contaminated with cocaine," Ebejer stated.
This finding mirrors work from an ongoing research project at Dublin City University. PhD student, Jonathan Bones, working under the supervision of Prof Brett Paull at DCU's National Centre for Sensor Research showed that 100 per cent of a sample of bank notes collected in the greater Dublin area were contaminated with cocaine.
The UK researchers took notes from a mix of urban and rural, well off and less well off and from ports of entry for drugs such as an airport or ferryport. They added a random "dummy" condition, whether the person collecting the notes for testing wore their watch on the left or right wrist, Lloyd said.
"We found that none of these factors were significant. They were all as significant as whether the watch was on the right or left hand," he added. "Across the country the contamination [ level] was more or less the same." This data is significant in that it counters the defence by some suspects that notes recovered from a drug-ridden area will have higher contamination levels.
Money seized in an investigation would typically be tested for drug contamination and the suspect would argue high levels were because drug use was prevalent in an area, and not because of cross-contamination caused by physically handling drugs and then the notes.
"The fact that it comes from Heathrow or 'drugville', the contamination of the cash and the general circulation are the same case anywhere in the UK," Ebejer declared. "We still get faced with that in court but now we do have the scientific evidence to back it up," he added.
The research data has been used in a variety of cases taken under the UK's Proceeds of Crime Act, money laundering cases and regular drug supply cases, Ebejer indicated. Contamination levels on seized money are compared with notes in general circulation and if there is a significant disparity it represents circumstantial evidence of value to the prosecution. "If 90 per cent of the notes seized are above the line, this is very unusual," says Lloyd.
While cocaine is found on virtually all notes, other drugs also leave a signature, Ebejer says. Traces of ecstasy and amphetamines are found on almost 50 per cent of notes and heroin and cannabis are detected on about 5 per cent of notes sampled.
The traces are absolutely minute, says Ebejer. "We are talking in the area of nanograms," or a thousand-millionth of a gram. The mass spectrograph detectors are able to pick up these very low levels.
There is a lot of speculation related to why cocaine is so prevalent compared with other drugs. Ebejer suggested as a powder it adheres very well to the fabric-like notes, aided both by the ink used in printing and the oils in the skin.
Once on a note, its passage from hand to hand via transits through bank counting machines helps to contaminate both equipment and adjacent notes.