Flashback Friday: How Much Cocaine Is in Your Wallet?

By Seriously Science | February 9, 2018 6:00 am

Image: Flickr/Tax Credits

Image: Flickr/Tax Credits

Urban legend has it that “all” of our paper currency is tainted with cocaine. These scientists decided to test whether this is true, and if so, how much of the drug is there. By testing over four thousand bills of various denominations gathered from 90 locations over more than a decade, they estimate that the “average” bill carries only 2.34 ng of cocaine (a tiny, tiny amount), but any given bill has ~15% chance of having more than 20 ng… which is still a tiny amount, but it’s there! Um… yay?!

The quantitation of cocaine on U.S. currency: survey and significance of the levels of contamination.

“It has long been suspected that the illicit distribution of cocaine in the United States has led to a large-scale contamination of the currency supply. To investigate the extent of contamination, 418 currency samples (4174 bills) were collected from 90 locations around the United States from 1993 to 2009. The extent of their cocaine contamination was quantitated via gas chromatography/mass spectrometry or liquid chromatography/mass spectrometry. The level of cocaine contamination was determined to average 2.34 ng/bill across all denominations ($1, $5, $10, $20, $50, and $100). Levels of cocaine contamination on currency submitted to the Federal Bureau of Investigation Laboratory in criminal cases over the 1993-2001 timeframe had significantly higher contamination than currency in general circulation. A mathematical model was developed based on the background survey that indicates the likelihood of drawing a bill in specific concentration ranges. For example, there is a 0.8349 likelihood that random bill will have contamination less than 20 ng.”

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  • OWilson

    Was there a greater cocaine contamination on the $100 dollar bills to validate the common culture perception?

  • http://www.mazepath.com/uncleal/EquivPrinFail.pdf Uncle Al

    Easily detect populations using what and how much via sewage assays of drugs’ metabolites.

    … 1) War on Drugs Federal drug control budget request for Fiscal Year 2018 is $27.57 billion.
    … 2) National Science Foundation request for Fiscal Year 2018 is $6.653 billion: 24% of the War on Drugs.
    ,,,3) End the War on Drugs tomorrow. Street prices crash. Drug cartels go bankrupt. The War on Drugs is the war on citizenry.

  • Not_that_anyone_cares, but…

    Has anyone published a procedure form ”literally” laundering my money to wash off any residue?

    Disclaimer: Query out of curiosity only. I don’t think I have any currency and have never done any street drugs.


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