A study that tested paper money from 30 big cities in five countries—including the U.S., Brazil, Canada, China and Japan—found that big metropolitan areas in both Canada and the U.S. have an alarmingly high presence of cocaine on their currency, with traces of the narcotic on 85-90% of bills. Brazil, coming in just behind the North American nations, had contamination on 80% of paper money. On the other end of the spectrum, in China and Japan, cocaine was present on a much lower 12-20% of banknotes.
