Contaminated Currency - in The United Kingdom

In The United Kingdom

Forensic scientists have said that around 80% of all British banknotes contain traces of drugs. A 1999 study found even higher levels of contamination in the London area; of 500 notes tested, only four had no traces of cocaine. Most of the banknotes showed only low levels of contamination, suggesting they had merely been in contact with contaminated notes, but 4% of the notes in the study showed higher levels, which the researchers suggested was the result of either being handled by people under the influence of cocaine (which is excreted in skin oils), or by being used directly to snort the drug.

There are drug levels above which banknotes need to be taken out of circulation, and over £15 million worth of notes are destroyed annually for this reason. The destruction is more often done as a precaution than because the money poses a serious health hazard.

Cocaine is the drug most commonly found on banknotes. Heroin and ecstasy are found less often, though the frequency of ecstasy contamination rose in the years leading up to 2002. Joe Reevy of Mass Spec Analytical, a company which analyses confiscated banknotes for the police, pointed out that heroin and ecstasy degrade more rapidly than cocaine, and that a single note which had been used to snort cocaine could subsequently contaminate many others when placed in a sorting machine, to explain the frequency of cocaine contamination.

Money recovered from police raids on the drugs trade are often heavily contaminated. In one raid in 2002, £465,000 was found which had been stored in a room where heroin was being prepared, and was so heavily contaminated that officers were advised not to touch it without protective equipment, while during Operation Uproar, an investigation into Colombian money laundering, $1 million in contaminated banknotes was destroyed after being seized.

Prior studies found that the level of contamination - i.e., the concentration of the contaminants - was different between those notes suspected to be used in the drug trade and those of proximity transfer levels. Subsequent tests have confirmed this determination, and serve as the basis for court cases against drug dealers, since the basic level of drug contamination remains fairly constant throughout the UK, despite factors that might immediately be thought to affect levels, like rural or urban environments, rich or poor or areas with high or low crime rates.