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Disappearing Fingerprints

07 Jun

Fingerprints have undoubtedly been the most successful method of absolute identification in history. No two people have the same fingerprints, including identical twins. We carry our fingerprints with us everywhere we go, we leave them on surfaces that we touch, they are easily collected and analyzed, and there is a national fingerprint database (Automatic Fingerprint Identification System or AFIS) that allows law enforcement to compare prints collected from widespread locations. Fingerprinting has a long history and was first used in a criminal case in Argentina in 1892. Since then it has found its way into courtroom after courtroom and has helped solve innumerable criminal cases.

Why do we have fingerprints? Are they just for identification or do they serve some purpose? Actually, they’re critical to many of the things that we do on a day-to-day basis. Here’s an experiment for you: smear butter on your fingers and then try to pick up a glass full of water. Not easy to do and will likely create one heckuva mess. Our fingerprints give us traction and grip and allows us to hold on to things. In technical terms they are called friction ridges.

Certain cancer drugs, like capecitabine (trade name Xeloda), can eradicate fingerprints. When someone takes this medication for several years, it can rarely cause what is called hand-foot syndrome. This is a drug-induced inflammatory process that involves the hands and feet. The skin becomes inflamed, and then swells, blisters, cracks, and bleeds. Over time, this recurrent damage to the skin can result in a complete loss of fingerprints or at least a significant attenuation of them so that they are difficult to detect. This has led to problems for some cancer patients when trying to get through airports around the world.

Could you use this in a novel as a way for your bad guy to eradicate his fingerprints? Not likely. It appears that for someone to develop hand-foot syndrome they must be on the medication for a number of years, which makes it impractical. Plus, this is a chemotherapeutic agent, and as such, possesses numerous other side effects. Things like fever, chills, diarrhea, nausea, abdominal pain, weight loss, and stomatitis (inflammation and erosions of the mouth and throat). Wouldn’t that make for a pleasant villain? Also hand-foot syndrome is rare so there is no guarantee that your villain, even if he did take the drug for a couple of years, would lose his fingerprints. In fact, the odds are against him.

For years, criminals have attempted to remove their fingerprints by various methods. The infamous John Dillinger used acid while others have used fire, hot pokers, and all kinds of cutting instruments to try to cut away or alter their fingerprints in such a way that they cannot be identified. Actually, the exact opposite is the case. When someone adds cuts and scrapes and burns to the pads of their finger, they are actually adding even more unique identification marks. It is similar to a car tire that has picked up cuts and scrapes from the road, or rocks or bits of glass embedded into its treads. If a tire impression found at a crime scene reveals these types of wear patterns and foreign bodies and if a car is then located whose tire exactly matches the pattern, then that is very strong evidence that it was this tire that laid down the crime scene impression and that no other tire could have had the same constellation of wear patterns and foreign bodies. In other words, this only makes the tire more identifiable. The same is true with fingerprints. If an individual has scars on his prints that exactly match those of prints left at the crime scene, then he has done the police a favor by adding these very unique and individualizing characteristics to his fingerprints.

Here are a couple of articles on this drug and one on the history of fingerprinting:

Vancouver Sun Article

Natural News Story

The History of Fingerprinting

 

19 responses to “Disappearing Fingerprints

  1. Pat Browning

    June 7, 2009 at 10:32 am

    How reliable are ffingerprints left at a scene? How long do they last?
    Pat Browning

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    • D.P. Lyle, MD

      June 7, 2009 at 11:14 am

      Fingerprints found at crime scenes come in all flavors. Some are smudged or smeared or laid down on a poor surface and are basically unusable. Others are clean and clear and left on smooth surfaces like glass and tiles. And anywhere in between. Some are only partial, some only a single finger, and others are a full set. So how useful any print is depends upon how clear it us, what surface it is left on, and whether the environment has damaged or removed it before its discovery. In a protected place such as a house or garage or tomb, if the print is deposited on a smooth, clean surface it can remain for many years and even decades.

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  2. Pat Browning

    June 7, 2009 at 11:22 am

    Can fingerprints be lifted from a victim’s skin?
    Pat Browning

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    • D.P. Lyle, MD

      June 7, 2009 at 11:33 am

      Not very often. On a living human you have about 90 minutes or less under ideal circumstances, while on a corpse as long as 24 hours or so. But this is under ideal conditions and with a bit of luck. This is a simple, everyday print. If the print is left with blood, paint, grease, or something else that might last a while, then all bets are off. Such prints could last for days on the living and for many days or weeks on a corpse. If left in paint, for example, the print might remain visible until the corpse decays enough to destroy the skin beneath the print.

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  3. Pat Browning

    June 7, 2009 at 11:47 am

    Makes you wonder how the cops solved cases before fingerprinting! Thanks for the good informatrion.

    Pat Browning

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  4. Leann Sweeney

    June 8, 2009 at 8:58 am

    I recently had to be fingerprinted to renew my nurse’s license. (This is new for the state). I do not have any matchable fingerprints–a little different than having NO fingerprints. I was printed twice and they ended up having to do a criminal background check by name instead because all I really create when printed are black blobs. You can see a few swirls but not many. When I blogged about this, I heard from 3 latent print experts that indeed, someone who has washed their hands with strong disinfectants for years and years may actually render their fingerprints unmatachable. I was very surprised by this but it explains why I am always dropping things, right? LOL (at least that’s what I tell my husband).

    Leann, who plans to somehow include this in an upcoming novel

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  5. Joann Breslin

    June 9, 2009 at 4:24 pm

    Don’t forget about food preparers and most especially nurses. I’ve read where some nurses fingerprints have totally disappeared!!

    Joann

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    • D.P. Lyle, MD

      June 10, 2009 at 6:02 am

      Never heard of either of those occupations leading to fingerprint loss. Not sure why they would. I’ll look into it.

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  6. Marie Nagy

    June 9, 2009 at 7:31 pm

    Last year I got a job for city working the kilns for their ceramics studio. Since the job also deals with public I was send to the police station to be fingerprinted. After one hour and approximately 40 attempts The policewoman given up and send me home. I gather that both continuous handwork with rough materials and the chemo I just came off could make my fingerprints disappear. And talking about murder What temperature does it take to burn up human body? We fire up to cone 10 which is 2350 F. And I keep thinking I got enough room in the kiln for a human body, the kiln is often fired overnight and over weekend thus no people are around and thus if I was so inclined I might take advantage of the facilities for more than firing ceramics. In any case I think if we reach high enough temperature that could work in fiction.

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    • D.P. Lyle, MD

      June 10, 2009 at 6:20 am

      Yes, working with high heat and/or abrasives can wear down fingerprints—not really remove them but flatten the ridges so that standard fingerprinting techniques aren’t always useful. During cremation, the crematorium is heated to 1500 degrees or greater for around 2 hours. This will destroy the corpse though teeth and some bone fragments might survive. Yes a walk-in kiln could be used to get rid of a corpse.

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      • Joe Macatelli

        December 26, 2009 at 7:50 pm

        Really??? Does anyone not find it odd that Marie is asking about the temperature needed to burn a corpse? Especially since she says that she might take advantage of the opportunity…..

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      • D.P. Lyle, MD

        December 27, 2009 at 10:17 am

        No, not odd. It’s just how crime writers think.

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  7. handfacts

    June 13, 2009 at 3:42 am

    This fascinating research!

    The source below includes some additional details about the findings of Roland Ennos & the research that preceeded his work:
    http://www.handresearch.com/news/fingerprints-unlikely-increase-hand-grip-friction.htm

    Including a few more quotes made by Roland Ennos:

    “So what are these prints for? My preferred theory is that they allow the skin to deform and thus stop blistering. That is why we get blisters on the smooth parts of our hands and feet and not the ridged areas: our fingerpads, palms and soles.”

    The human skin behaves like ‘rubber’, despite that fingerprints help do not to give our hands more grip they do help us to make a better grip!

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    • D.P. Lyle, MD

      June 13, 2009 at 8:27 am

      Thanks for this. It is interesting. Not sure I agree with him completely since the ability to grasp and hold things would be an advantageous evolutionary development. Less blistering would be too but grip would be even more important. I’m sure this is argued about among those that research this type of thing.

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  8. G

    August 3, 2013 at 8:32 am

    FYI you say being a nurse would not cause fingerprints to disappear? My friend cannot get hired in state of florida even a FBI agent cannot get her prints thirty years experience down the drain…she can collect unemployment…we cannot afford to start losing these nurses.

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    • D.P. Lyle, MD

      August 3, 2013 at 8:41 am

      Not sure what you are saying but all the nurses I now have fingerprints. So being a nurse will not make your prints disappear. I suspect you mean she had some other condition but the way this is worded sounds like her being a nurse is what caused whatever the problem is.

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    • Leann Sweeney

      August 3, 2013 at 9:18 am

      Yes, after 35 years as a nurse they could not get my prints. The fingerprinter actually groaned when she saw my profession. It is NOT an uncommon problem. What they did is certify me as “not printable” and had my “smudges” on file to prove that I made the effort (three times!)

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      • Leann Sweeney

        August 3, 2013 at 9:22 am

        Oh, and I had to have a criminal background check, too, to renew my license.

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  9. Carroll Tilghman

    September 4, 2013 at 6:47 am

    Interesting following that link. The Boy Scouts have a fingerprinting merit badge. Who knew?

    Like

     

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