COACAINE CONTAMINATION IN BANK NOTES

In what researchers describe as the largest, most comprehensive analysis of cocaine contaminatin in bank notes reporting that cocaine is present in up to 90 per cent of US bank notes
The scientists found traces of cocaine in 95% of the bank notes analysed from Washington D.C. alone. Scientists tested bank notes from more than 30 cities in five countries, including the US, Canada, Brazil, China, and Japan, and found "alarming" evidence of cocaine use in many areas.
The US and Canada had the highest levels, with an average contamination rate of between 85 and 90 percent, while China and Japan had the lowest between 12 and 20 percent contamination. The study is the first report about cocaine contamination in Chinese and Japanese currencies.
Scientists have known for years that paper money can become contaminated with cocaine duing drug deals and directly through drug use such as snorting cocaine through rolled bills. Contamination can spread to bank notes not involved in the illicit drug culture because bills are processed in banks' currency-counting machines.
"To my surprise, we're finding more and more cocaine in bank notes," said study leader Yuegang Zuo, of the University of Massachusetts in Dartmouth.