Low levels of cocaine have been found on all the Irish bank notes tested in a recent survey.

As part of a major study into illicit drug use within Ireland, Brett Paull and colleagues at Dublin City University have taken advantage of recent developments in liquid chromatography coupled with mass spectrometry to detect contamination on Irish euro notes. Traces of cocaine were found on every one of the 45 used notes analysed, and traces of heroin were found on three notes.

Higher levels of cocaine were found on the higher denomination notes, and of the 45 used bank notes, two showed levels that would suggest direct contact with the drug, probably from being used to inhale the cocaine, Paull suggested. The team suspects that the cocaine found on the other bank notes is due to cross-contamination between notes in the counting processes in financial institutions.

According to Paull, the presence of drugs on these bank notes could be an indication of the presence of the narcotics within the local community. Media reports suggest that the use of illegal drugs in Ireland has escalated dramatically recently.

'An annual survey of this type may be carried out to evaluate any changes in the average degree of euro note contamination,' said Paull.

The research also illustrates the high performance of newly available chromatography equipment for this sort of work.

Linking the findings of this study back to drug use statistics is a challenge to be approached cautiously, said Paull. 'What do these results really tell us about the subject of community drug use and do these results act to stimulate debate or stir up concern?' he asks.

Caroline Moore