LONDON — Sober? That doesn’t necessarily mean that you’ll pass a drug test, a new study finds. That’s because one in every eight people are walking around with traces of cocaine on their hands — and there’s a good chance they have no idea where it came from.

Researchers at the University of Surrey in the UK recently tested the fingerprints of 65 volunteers, 50 of whom reported not using drugs, to determine whether regular citizens could mistakenly test positive. Perhaps so: 13 percent of participants who self-reported being clean had traces of cocaine on their fingertips, while another one percent had minute levels — about one metabolite — of heroin, the researchers found.

Person holding out their hand
A new study finds one in eight people are walking around with traces of cocaine on their hands — and they likely have no idea where it came from.

A subsequent part of the experiment had the group’s drug-free volunteers shake hands with its drug-using subset, which allowed the researchers to analyze the sober volunteers’ fingerprints afterwards. The fingerprint analysis showed that tests could still reliably differentiate between actual use and secondary contact, findings that law enforcement could use in criminal proceedings.

In case you’re wondering, that magic cut-off point is one metabolite.

“Believe it or not, cocaine is a very common environmental contaminant— it is well known that it is present on many bank notes. Even so, we were surprised that it was detected in so many of our fingerprint samples,” says researcher Dr. Melanie Bailey, a lecturer in forensic analysis, in a university media release. “[However], we can give those tested the piece-of-mind of knowing that whatever the result of the test may be, it was not affected by their everyday activities or shaking hands with someone that had taken drugs.”

The results held true even after participants washed their hands.

Although most drug tests are still done through more traditional means, such as blood or urine, the researchers firmly believe that fingerprint testing is the wave of the future.

“There are many factors that set fingerprint testing apart — it’s non-invasive, easy to collect and you have the ability to identify the donor by using the sample,” explains Mahado Ismail, the study’s lead author. “Our study will help to add another robust layer to fingerprint drug testing.”

Ismail et al. published their findings in the Sept. 2017 edition of the journal Clinical Chemistry.

About Daniel Steingold

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  1. centexfan says:

    And those folks are in Houston, Miami, Ft Lauterdale, Chicago, NY, LA…dubuque Iowas…not so much

  2. Dr. Billingsgate says:

    Throw them all in jail and let God sort them out.

  3. Moose says:

    legalize it.

    1. centexfan says:

      I don’t care what they do in thier hoes..I jsut want to make sure they staff of the roads…if there is a test for impairment like a breathalyser for booze…have at.

  4. Mr Happy Man says:

    Cocaine found on dollar bills? I never knew that was a possibility!

  5. plebian says:

    Well, here is another article to promote the end of cash. People!!!! little articles like this eventually become Democrat talking points to bring on a cashless society

    1. republican_jeezus says:

      The business sector brings on the cashless society. Demand due to convenience and efficiency. Democrats do not run the business world.

  6. RLABruce says:

    All cash tests positive for drugs. If your money is ever taken as evidence of a crime, kiss it goodbye, because it will be confiscated as drug money, whether you are ever charged or not. They will no doubt use it to fund their anti-drug programs.

  7. david4041 says:

    My friend was a govt. accountant. One of his jobs was to count the money seized in drug busts (for possible tax evasion charges). One time, he got so high off the cocaine on the money he was sent home.

  8. David Mowers says:


    ….and while you are at it end the other TWO wars on the impoverished; Gambling and Prostitution.

    Victimizing the poor is what capitalism is all about.

  9. RINOSHaveAbusedBase4LastTime says:

    Nay…not me. My hands are in Palmolive dish soap w/Oxy too many times a day. The rest of the time is spent luxuriating in Goats Milk Lotion!!!

  10. Littleredtop says:

    Dirty money. Paper bills are covered with questionable substances including cocaine. The dirtiest bills are those collected in strip clubs. Those bills are laced with perfume, after shave, drugs of all sorts, perspiration, all forms of bodily fluids and feces.

    1. Tim Reynolds says:

      Aren’t you just a bundle of joy…

      1. Littleredtop says:

        it’s a fact – a woman in California even claims to have been impregnated by a soiled bill when she stuck it in her panties for safe keeping.

    2. Dr. Billingsgate says:

      Now I know why my wife makes me take a shower after I go to Cheetahs.

      1. Littleredtop says:

        That’s important too but remember to always leave all your paper money there before you go home. I like to take all my paper bills and fold each into an origami swan and have the girls pick them up without using their hands. They seem to enjoy that.

  11. David Mowers says:

    Is it time to legalize drug use or should we continue to ruin lives, waste billions and prosecute activity that is personal behavior?

    Time to end the charade here, everyone, I mean everyone you meet anymore is a drug user, has used drugs or knows someone using them. This has become a joke.

    Armed with this information a police officer can charge you with possession of drug paraphernalia just for carrying cash. Can you imagine not having to ingest illegal substance because they are legal and people can just use drug-oriented paraphernalia instead of dollar bills to snort their drugs? Or do you need to wait until an overzealous cop forces you to pay for lab tests to prove how old the cocaine on your bills was? Expected to spend thousands of dollars defending yourself because you committed the crime of carrying cash.

    1. acronymous says:

      Opioid overdoses are killing more than 50K Americans per year and you want them made street legal? Let’s go for 100K, hey? Why not 200K? Already we’re losing people faster than we were in WW2.

      Some of this stuff has to remain illegal. I’ll take my chances being convicted on such thin evidence as that it looks as though I handled cash recently, and that might have been because I was sniffing green ink.

      1. Doug Wakeman says:

        Aren’t the people dying from Opioids taking them voluntarily? I think many thousands of people die each year from voluntarily engaging in risky activity. That’s their business, not the Feds.

      2. BIoodEagle says:

        The difference is negligence. Is your customer fully informed of the ingredients? Purity? Deadly contaminants? This is why you can’t “legalize” street drugs. You’d have to re-write mountains of liability laws or end up right back where you started with a regulated market.

      3. Doug Wakeman says:

        Sorry, if someone wants to partake of “street” drugs that is their business and theirs alone. They must take the risk of impurity and contaminants upon themselves. That is the nature of individual freedom. That is the bedrock of liberty. In order for the people to be free to pursue their creative urges as they see fit to achieve their goals in this one life we live we must also allow people to travel down whatever destructive path that their flawed humanity drives them. To restrict one is also to restrict the other. It is the sad result of the tragedy of human nature that in order to allow the best to flourish and achieve we must also allow the worst to flounder, fail and fall by the wayside.

        By the way, I don’t care if “street drugs” are legalized or not. I am only concerned that the cancerous pit of filth and corruption that is Washington DC has no say in the matter. The Constitution gives the central government no authority in these matters. That means it is left up to the states. And each state should be allowed to legislate drug policy in whatever manner they wish. But if the matter came up in my state I would support allowing people to ingest, smoke or inject into their own bodies whatever the Hell they wanted. They are the owners of the own bodies and lives and let them do as they wish and let the chips fall where they may.

      4. BIoodEagle says:

        That’s the beauty of American government. Americans are free to govern themselves however they see fit. It is wrong to force laws for or against drugs on communities who reject them. This is the function of jury nullification, which has been upheld by the Supreme Court as a legitimate check by the people against government overreach.

        I’m not disagreeing with your philosophy, there is nothing stopping your state from legalizing whatever they want. How many states have to legalize cannabis before people begin to realize that there is no such thing as federal prohibition? It doesn’t exist. That is a power not granted to the fed, which becomes a states right by default.

        There is however, a clause allowing the federal government to regulate interstate commerce. I don’t see how drugs are some kind of special that should be exempt. Why should every other tax-dodging smuggler go to jail if we give drug dealers a free pass? How will the people collect all those taxes they were promised for legalizing weed if there’s nothing stopping you from crossing their border with tons of it? Not to mention the legitimate growers and dispensaries who follow the rules and pay their taxes having their prices undermined. If you support states rights then why wouldn’t you want the federal government to arrest smugglers?

      5. acronymous says:

        The thing about addiction is that the first pill is voluntary, perhaps, but what about people who get hooked by prescription opioids?

        In any case, eventually it’s not all that voluntary. The opioids conscript the brain’s reward and pain system and the addict is next to helpless.

        These people are being murdered by their suppliers, and it isn’t even legal, and you want it legalized the rest of the way. Shameful, really.

      6. David Mowers says:

        Who makes and prescribes those opiods?

        According to 60 minutes the day of the Super Bowl THIS CURRENT CONGRESS voted AGAINST prosecuting doctors, distributors, HMO’s and clinics for over-prescribing opiod painkillers.

        Congress voted to addict and kill your children.

      7. centexfan says:

        Try to keep up. That saw that it is big pharma and the docs that did this evil thing is is the governmnet…by requiring that patients who complain of “pain”” to be managed and if the dc does not meet the patient’s expectations then the doc is sanctioned. SO every lazy freeloadign SOb with “back pain goes in and gets his prescription and stays on disability for decades. Got one in my neighbohood been disability for 20 years..but manages to mow his lawn, prune his hedge, and build a deck aroudn his pool. By keeping the f’ing border open they are importing the heroin that is cheaper by far and way more available than any prescription drug.

      8. acronymous says:

        You have a point. I would rather see the law changed so as not to yank the rug out from under people who had reason to think that what they were doing was legal. Pharm lobbied hard for rules that no doctor may ever tell a patient in pain to suck it up a bit. So for the time being, MDs are a bit stuck between a prudent concern over addiction, and fear of being disciplined for letting a patient suffer, even if it’s bearable and transient pain. For my own part I’d rather just suck it up. If I had severe chronic pain I might not look at it the same way, though.

      9. David Mowers says:

        The State of Virginia a few years back voted to allow the same pill-mill pain clinics that Florida shut down.

        I can go use the same prescription and get it filled three times and when I am so addicted that it no longer works any doctor in Virginia will write me a new prescription for a harder drug.

        I know people getting 180 pills a week of morphine prescribed to get them OFF Oxycontin.

        Tell how that is legal, moral or ethical.

        It’s about selling drugs and making money of another person’s misery the only difference is whether or not the drug dealer funds political campaigns.

      10. acronymous says:

        On this point, we are in agreement. You have been treated horribly, and it’s criminal to allow it.

      11. David Mowers says:

        One distributor sold 23 million pills in a single town in WV “legally.”

      12. Alf says:

        My son is a heroin addict, I’d rather see him die from OD, than be put in prison based upon his personal decision to inject himself with lethal drugs. The biggest drawback from drug abuse and use is prison.

        Look, these people are already ruining their lives, why help them in that endeavor and why should we tax payers have to pay for it?

      13. David Mowers says:

        Why destroy people for being depressed and self-medicating by throwing them into pens with violent psychopaths?

        Unless you want to create more psychopaths.

      14. RLABruce says:

        What about the harm drug users do when they kill or injure people by driving under the influence, or turn to prostitution or burglary to fund their drug habit? Druggies are not employable, so even if the “legal” cost of their drug of choice is lower than the illegal cost, they will still commit crimes to finance their “legal” habit.

        Hell, let’s go whole hog and make EVERYTHING legal! Murder, rape, assault, mugging. All these people, the criminals, are already ruining their lives, so why should we taxpayers have to pay for it?

      15. republican_jeezus says:

        Drug users are generally committing non-violent offenses. To consider moving money from enforcement and prison to treatment is not a crazy idea at all. It would save an incredible amount of money. Even if people went to clinics to get their drugs and they were free, still way cheaper than the ccops-courts-private prison system racket.

        People still kill people while driving under the influence of alcohol, over the counter medications and legal prescriptions. Sometimes just from being too tired.

        You either haven’t thought it through, or you are a cheerleader for the current system which has failed. America is number one in incarcerated people of any nation in the world, and the majority of the prisoners are non-violent drug offenders. It’s a money racket.

        People should be open to new solutions that save money and improve people’s lives.

      16. Alf says:

        WHat about, what about what about…

        How about this…

        What about all the gun owners that could go and kill a bunch of people, but, don’t?

        How about all the people that drink alcohol that could go out driving around but instead stay home act responsible?

        See how that works?

      17. centexfan says:

        NOpe it is and blood borne disease form Hepatitis to AIDs..and an absolutley wasted life.

      18. lngshirt says:

        My daughter is also and I agree completely. Her life is on course for the time being but if she would have been jailed her life would have been over. No doctor or drug company got her hooked on heroin. It was the drug the dealer had when she went to get weed, coke,or whatever drug happen to be on the market.

      19. BIoodEagle says:

        If you’re telling the truth then you are enabling his addiction. I had a nice long conversation last week with a sergeant at the local PD about the addict in my house. Why? Because that’s how you get an addict into rehab who doesn’t want to go. Not that it will make them get clean right away, if ever, the point is to put them in a safe place with positive vibes even if it’s only for a short time. Less likely to OD, get shot, arrested, steal from family, etc while you’re in rehab, ya know? Bonus points if your private insurance covers it, that way you can save the taxpayers some money if that’s what’s important to you.

        I find it very unusual that you would rather your son OD than have to go through the system. Better to get a year in county now than 20 years in prison down the road, addicts get worse the more time you give them. If you haven’t learned that the biggest “drawback” from drug abuse is the emotional devastation they inflict on the people who love them then you must be new to the game.

        Listen to people who have been through it and have years of sobriety behind them instead of the activists who would just as soon sell you drugs than give you honest advice.

      20. Alf says:

        You have no idea about my life, or where my son lives… You assume a lot to make yourself look like a fugkin’ idiot.

      21. BIoodEagle says:

        The only thing I’m assuming is that you made up the entire story.

      22. Alf says:

        Yes, because, people just want to make up stories about their heroin addicted kids to share with anonymous strangers on the internet.

        Grow a fugkin’ brain, would yah, finally?

      23. BIoodEagle says:

        Anybody who supports the legalization of filthy impure street drugs is a person of extremely low moral character. Likely drug addicts themselves. All they do is tell lies. Lie about the laws, lie about statistics, lie about the dangers, lie about their own drug use. Lie about human nature. Act like nobody would ever make up a dramatic story that promotes the legalization of drugs.

        If your post was more about your “son” than it was about legalizing deadly substances it might have been more believable.

      24. Alf says:

        Yeap and welcome to mute… I am done with talking to an ignorant insultive douchebag.

      25. 40_rods_to_the_hogshead says:

        Bless your heart, you’re just a dumb dumb who thinks he has a moral compass.

      26. BIoodEagle says:

        Is that the best you can do?

      27. Pat says:

        This entire “losing people faster than world war two” is absurd statistics usage. What matters is trends with all variables including per capita considered. EI vehicular deaths are down 20% per capita the past 25 years, gun murder per capita is down about 60% ( a vast majority think it is up), and drug/alcohol deaths are slightly elevated at about 22% increase — but almost all of that increase is because the AGE of the population is increasing and there are more elderly people dying. For example lifelong drinking or lifelong drug abuse is marked by CDC as drug/alcohol causal if an elderly person dies of liver failure/disease (eg. cirrhosis or hepatitis).

      28. republican_jeezus says:

        It’s White Folk hysteria. No one batted an eye at the Crack and Cocaine epidemics of the 1990s, because it was happening in inner cities. But heroin is a white suburban drug and once it caught a little, the privileged folks have gone into hysterics.

      29. Alan C says:

        You say that as if it’s a bad thing.

      30. 40_rods_to_the_hogshead says:

        “But heroin is a white suburban drug” Uh no, its an everywhere drug.

      31. BIoodEagle says:

        “It’s White Folk hysteria. No one batted an eye at the Crack and Cocaine epidemics of the 1990s”

        I guess all the black people who complained about it were “no one”.

      32. acronymous says:

        Lifespan among whites with less than college is falling. That’s not because they’re living longer. It’s falling even though murder and auto accidents are abating. It’s falling even though we now have better treatments for cancer and heart disease.

        Opioids, and alcohol abuse, are problems that are growing so rapidly that they offset and overpower all the other good trends.

      33. 40_rods_to_the_hogshead says:

        “Opioid overdoses are killing more than 50K Americans per year” Absolute bullshit.

      34. acronymous says:

        Fine. Go ahead and make it 50001. I do care about those who fall into it. But those who think they can play Judas goat and slip free? Not so much.

      35. 40_rods_to_the_hogshead says:

        I don’t take any, the point is the numbers are bullshit. In no way shape or form are 50,000 people a year dying of opioid abuse. Your stat is garbage.

      36. acronymous says:

        The most recent numbers seem to be behind a paywall. But Wikipedia article has the death rate at 10 or 11 per 100K in 2015. That would make for about 33000 opioid overdose deaths a year then. There’s a graph and it’s steeply rising. This makes 50K not that implausible.

      37. 40_rods_to_the_hogshead says:

        Wikipedia said that? Well now I don’t know WHAT to think!

    2. Charles_Miller says:

      No. “Legalizing” drugs has never been an answer.

      1. republican_jeezus says:

        It sure was when the prohibition on alcohol was lifted in the early 1900’s. Knowing one’s own history is always helpful.

      2. David Mowers says:

        God made them legal when The Lord made the plants.

      3. David Mowers says:

        Three Hundred Years of failure and counting…I suppose we need to lose another three hundred years or revenue before you grow the f_ck up.

  12. Mr. H says:

    as to cocaine on your hands goes, all that means is you have handled paper money since you last washed your hands well. All of our circulated paper money has traces of cocaine. That is probably true world wide for all paper money.

  13. sirlanse says:

    If they use it, they can convict 1 of 8 people, without any other proof. How wonderful as a negotiation tool. We have coke on your hands, that is 5-15years, what can you tell us about your boss?

    1. Steve Hardy says:

      Not sure what the laws are where you are from but here in the United States it takes a lot more than trace amount of cocaine on your hands to lead to a conviction.

      1. Alf says:

        yeh, Britain is ridiculous.

      2. David Mowers says:

        Nope. A trace amount found on bills automatically makes those bills drug paraphernalia. Ask any attorney or police officer. Good Luck fighting the charges…90% of all convictions are due to plea agreements where the person charged is too poor to fight it and accepts a reduced charge in lieu of bankruptcy.

        That’s tells you what “justice,” is in America and it wholly explains the rage fomenting among minorities.

      3. republican_jeezus says:

        It’s true. You can buy justice in America. Ugly but true.

      4. David Mowers says:

        In China I can murder people and pay rural farmers two million dollars to serve my sentence.

        Mitt Romney-style justice huh?

      5. Chris Atwell says:

        Years ago, I heard about a case in the US where a lawyer entered in to evidence that a lot of dollar bills in the US have trace amounts of cocaine. I think the evidence swayed the judge. Don’t ask me any questions because that is all I recall.

      6. David Mowers says:

        Los Angeles….I live in North Carolina. In rural north carolina you are going to prison for having cocaine residue on your bills. End of story son, tell it to the judge.

    2. david4041 says:

      Or they can use the presence of trace amounts of cocaine on money to seize (and keep) the money seized under the practice of civil forfeiture. You don’t even have to be charged by law enforcement for them to keep the money. Then you have to go into court and prove that the money wasn’t connected to drugs in order to get the money back.

  14. nick says:

    I’m feeling a little run down. Excuse me while I snort my fingertips….

  15. Bigg Bunyon says:

    Mama always said don’t put you fingers in your mouth. Looks like once again the old advice is the best advice.

    1. WardCleaver says:

      Mama from the third world never gave anyone this advice.