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Science

Aerosol Spray to Identify Bombing Suspects 191

RedHanded writes "Forensic chemists at the Hebrew University of Jerusalem have developed a color-changing spray that can identify people suspected of making or planting bombs. The chemical turns from yellow to bright red when it comes into contact with urea nitrate, an explosive residue that may be left behind on the hands of someone who has handled an improvised device."
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Aerosol Spray to Identify Bombing Suspects

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  • Basic hygiene (Score:5, Insightful)

    by LiquidCoooled ( 634315 ) on Wednesday September 19, 2007 @08:24PM (#20675203) Homepage Journal
    How many false alarms are they going to get after people don't wash their hands after visiting the bathroom?

    Maybe that is what they are looking for - poor hygiene = terrorist?

    Perhaps this chemical is the same one which makes the purple cloud of shame in the swimming pool (I know its a legend but still..)
    • by Anonymous Coward on Wednesday September 19, 2007 @08:26PM (#20675231)
      From the article:

      Spraying this substance in the air will show the farts of anyone in the room as a blue haze.

      Ha ! Finally some way to track down the lactose intolerant!
    • Re:Basic hygiene (Score:5, Interesting)

      by Upaut ( 670171 ) on Wednesday September 19, 2007 @08:43PM (#20675413) Homepage Journal
      Only if this person with bad hygiene sweats nitric acid...

      I'm more worried about, well, me... I use urea nitrate in my tropical orchid mix...
      • I use urea nitrate in my tropical orchid mix...

        Sure, sure, whatever you say.

        Just don't be offended if I don't shake your hand buddy.

        • Re: (Score:2, Funny)

          by Anonymous Coward
          Just don't be offended if I don't shake your hand buddy.

          He has a hand buddy? That's awesome. But yeah, I don't suggest you shake it.

      • Sweats Nitric Acid you say...

        *Goes to put on more Anti-Sweat Deodorant before heading off to the Airport*
      • Re:Basic hygiene (Score:5, Informative)

        by Rutulian ( 171771 ) on Thursday September 20, 2007 @12:01AM (#20676997)
        Unless you make it yourself, I think it is unlikely you have urea nitrate in your fertilizer. You probably have urea + potassium nitrate (or ammonium nitrate). To form urea nitrate, you need a strongly acidic conditions.

        From the article, the "amazing" new molecule is just commercially available p-dimethylaminocinnamaldehyde. The chemistry involved is already well-known. It is used for, among other things, indirectly detecting biotin (by way of the urea in the molecule). Basically you mix your urea-containing compound with a strong acid (sulfuric acid works), which promotes enol tautomerization and makes the normally unreactive nitrogens of the urea reactive toward electrophiles. One of the nitrogens will react with the aldehyde to form an imine, and due to the availability of a quinoid resonance contributor, turn color (red in the case of dimethylaminocinnamaldehyde and yellow in the case of dimethylaminobenzaldehyde).

        What's special here, and why this won't result in a thousand false positives from detection of any urea-containing compound, is that urea nitrate is a stable salt and acidic enough on its own to react with dimethylaminocinnamaldehyde without the addition of acid. So a wipe test, drop it in isopropanol, add some of the aldehyde and see if it changes color. It's a fairly elegant application of old chemistry to forensic analysis.
        • by ashitaka ( 27544 )
          Thanks for the extremely well-written, detailed and informative comment.

          Complete gibberish to anyone but chemistry majors but a good post nonetheless. :-)
      • Heart medication (Score:3, Interesting)

        by phorm ( 591458 )
        I remember somebody I know telling me about how she was stopped and searched, etc at the airport because she had traces of nitro on her hands and in her purse. Now why would she have that? Well her husband used it as a medication [medicinenet.com] for his bad heart.

        You'd be surprised at the rather harmless (explosion-wise anyways) uses many of these chemicals have, and I'm sure the airport guards may be as well. I've heard many cases of funky medications giving weird results in various situations. Did you know that taking
      • Now before I get started, bear in mind that not only I'm not a chemist, but Chemistry is one of the things I understand the least. So major talking out the arse follows. If anyone who knows chemistry better wants to correct me, please do, it's very much appreciated.

        That said, looking at the illustration of the mollecules interacting in TFA, it looks to me like their dye binds to just the nitrate anion, and there is no trace of urea to be seen at all there. I.e., what is so funnily coloured is their mollecul
    • Re: (Score:2, Interesting)

      How many people in their lifetime ever actually handle urea nitrate anyways? In my previous career I used to handle explosives and most explosives your don't want to handle with your bare hands since most of them are a health hazard also, not to mention the blasting power. The nitrates in the most explosives are basal dilators so you turn bright red because all of the blood vessels in your body are opening up. You may identify people that handle explosives this way but alcohol does the same thing so don't c
    • Re: (Score:3, Interesting)

      by Kingrames ( 858416 )
      More importantly, are there going to be people who walk around in airports spraying random people?
      This is why I stay away from certain areas of the mall.

      And more importantly, what will happen when someone yells "Security! This man is assaulting people with aerosol spray!" and the airport undergoes lockdown?

      Or more feasibly, what happens when the terrorists use the aerosol as an opportunity to walk around the airport spraying people's hands, infecting them with SARS or some other horrifying disease?

      Seriously
      • Re: (Score:3, Funny)

        by bloobloo ( 957543 )
        Don't you think it's more likely to be used when you go through security? You don't get random people walking up to you in the airport and pulling out an x-ray machine, do you?
    • by mrmeval ( 662166 )
      Just spray surfaces all over the place with some.
      Sheesh the morons.
    • Re:Basic hygiene (Score:4, Informative)

      by reverseengineer ( 580922 ) * on Wednesday September 19, 2007 @11:27PM (#20676767)
      Well, according this earlier abstract [astm.org] by the same group (the paper from two years ago where they originally propose the dye- the paper linked to the article is really just about using X-ray crystallography to study the structure of the dye/urea nitrate complex):

      Urea itself, which is the starting material for urea nitrate, does not react with p-DMAC under the same conditions. Other potential sources of false positive response e.g., common fertilizers, medications containing the urea moiety and various amines, do not produce the red pigment with p-DMAC. Exhibits collected from 10 terrorist cases have been tested with p-DMAC. The results were in full agreement with those obtained by instrumental techniques including GC/MS, XRD and IR.

      From what I know of the chemistry of aldehydes (there's a great icebreaker at parties...), this dye should react with any primary or secondary amine- like regular old urea, ammonia, amino acids, etc. What this group claims, however, is that there is a particular color change reaction for this dye which occurs for urea nitrate which does not occur for other amines.

      I think what the article's confusing picture of the dye and urea nitrate interacting is suggesting is that the hydrogen bonds between the nitrate and urea moieties remain intact even after the urea has bonded to the dye, so the nitrate moiety affects the dye complex and the color it appears. I'd still be concerned about false positives, personally, particularly from different amine salts. The color produced might be uniquely identifiable to a spectrophotometer, but for a visual test I'd be worried about anything that turns "reddish" enough to produce a false positive.

    • Re:Basic hygiene (Score:4, Interesting)

      by rve ( 4436 ) on Thursday September 20, 2007 @12:21AM (#20677131)
      The Birmingham six were convicted largely based on the result of such a test.

      http://en.wikipedia.org/wiki/Birmingham_Six/ [wikipedia.org]

      Indicator tests are nothing new by the way, and they're not inherently useless, as long as you realize that they tend to be non-specific, and usually react with a whole range of compounds. If you have a sample that you know may contain either substance A or B, and you know only substance B reacts with your color spray, then the reagent is a quick and reliable way to tell the difference.

      If on the other hand you start spraying it on people who may have been in contact with any number of substances, and then accuse anyone with a positive reaction of terrorism, innocent people are going to end up in jail.
    • by Kagura ( 843695 )
      There have long been Russian-produced explosives circulating in Iraq from cold war times that have a strong, yellow-orangish dye in it. A person handling it using their bare hands will be stained until their skin sloughs off. At one point, this was a method used to identify less savvy bomb-makers in Iraq.
  • bomb makers or... (Score:5, Insightful)

    by Jherico ( 39763 ) <bdavis@saintandreas . o rg> on Wednesday September 19, 2007 @08:26PM (#20675221) Homepage
    Bomb makers or maybe farmers who handle fertilizer? I don't envy being a false positive in Iraq.
    • The chemical turns from yellow to bright red when it comes into contact with urea nitrate

      Yet another excellent reason to wash your hands when you go to the toilet...

      ...actually, let me clarify that. A good reason to wash your hands after you go to the toilet.

      Washing them when you go is disgusting.

    • Re: (Score:3, Informative)

      I believe said farmer would have to urinate on their hands after handling fertilizer, not wash, and actually probably need to vigorously rub their hands together until they were hot to generate a positive on this test.
      • by julesh ( 229690 )
        I believe said farmer would have to urinate on their hands after handling fertilizer

        Urea is present in sweat, almost certainly in enough quantity to trigger this test. Besides, urea nitrate _is_ a fertilizer. See here [roguesci.org].

        not wash,

        You're likely to accumulate a similar quantity of buildup of nitrates on your hands handling an explosive compared to handling fertilizers. The test is almost certainly designed to catch people who have washed their hands after handling the explosives, so is likely to be very sensi
      • by hey! ( 33014 )
        Yes, but why take the risk?
  • great (Score:2, Insightful)

    by Anonymous Coward
    zillion dollar spray defeated by less than a cent disposable rubber gloves.
  • by Anonymous Coward on Wednesday September 19, 2007 @08:26PM (#20675237)
    It's a good thing that terrorists never wash their hands.
  • I recall that troops in Iraq had already started using silly string to detect IED's. Now we're going to spray paint people to try to find who made the bombs? I'm waiting to see what 7-11 product shows up on the battlefeild next...
  • I guess that means everyone boarding a plane will have yellow hands. I suspect they'll use up the plane's water reservoir trying to wash the crap off, too.
    • I'd hope no one thinks about massively aerosolizing this stuff (like spraying it throughout an airport to find terror suspects). From this Material Safety Data Sheet [sciencelab.com] for para-dimethylaminocinnamaldehyde, the dye in question: Potential Acute Health Effects: Hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion, of inhalation. That's why what's suggested in the article is to sample a suspect through swabbing, then testing the swab- not spraying directly on people.

      In additi

  • Congratulation! (Score:5, Insightful)

    by Daimanta ( 1140543 ) on Wednesday September 19, 2007 @08:28PM (#20675257) Journal
    Terrorists will now use gloves to make bombs. Innocent people will be falsely identified as being a terrorist.

    Mission accomplished!
    • Re: (Score:3, Insightful)

      by sumdumass ( 711423 )
      It will be on their shirts, or clothing from attempting to conceal it. Gloves won't hide the stuff either. If anything it would hid the person manufacturing it but then again a shower would do as much as gloves do.

      As for false positives, it isn't likely to be a problem. The stuff shows who the likely people are not who the person is. If you have a legitimate reason for the chemicals on you, you get to go. If you don't, then they look to see why you have it.

      It sounds like your pissed because they have found
      • Re: (Score:3, Insightful)

        by DaedalusHKX ( 660194 )
        You don't think it will be used on American civilians sooner or later? Kicking doors in and oppressive military tactics have come back to roost, look at abusive SWAT and cops... tazer usage is going out of hand, being used in the western work to nail kids (when I was a kid we used to get our ears boxed, not blasted with a tazer, and it worked better).

        If you're an American, and you hang out at the range, and the local scumbags decide to make that illegal, suddenly, having gone plinking or hunting is a crime
        • Re: (Score:3, Insightful)

          by sumdumass ( 711423 )
          Don't you think you are blowing things out of portion?

          Swat doesn't get called unless there is a barricade, ongoing threat of life or hostage situation. Cities don't have swat teams on standby to assist at traffic stops. They have cops on patrol that come off patrol when the swat team is called. Sometimes they go back and get their gear and sometimes their gear is loaded on a truck waiting for them on the scene. Swat forces havn't been abused in over 50 years so what makes you all the suddent think they will
          • Comment removed based on user account deletion
            • This violates the sprit of the posse comitatus act, and probably the letter of the law as well.

              Then you'd better quote some of this other "law," because local SWAT teams, no matter how they're equipped, have fuck-all to do with posse comitatus. That was enacted specifically to prevent federal troops - Army, Navy, Air Force, Marines - from engaging in the enforcement of federal law on US soil. It has nothing to do with their equipment or their training, and everything to do with who's giving the orders.

          • A doctor in upstate New York (who happened to have a carry permit) was issued a "warrant" by the locals, which was served by SWAT... one of the SWAT boys was a bit trigger happy (he was cleared of course) and mistook the doctor reaching into his coat to get his ID with him reaching for his weapon... (which he wasn't even carrying at the time). Shot him dead. The warrant in question?? A warrant in DEBT... no reason for SWAT... whatsoever.

            A bouncer at a club in Virginia Beach (I was going to college nearby
          • by sholden ( 12227 )
            Swat doesn't get called unless there is a barricade, ongoing threat of life or hostage situation

            Or they want to exercise a plain old search warrant.

            http://www.washingtonpost.com/wp-dyn/content/article/2006/01/26/AR2006012602136.html [washingtonpost.com]

            """
            But police officials acknowledged that the tactical team, using bulletproof vests, high-powered weapons and other police tools, serves nearly all of the warrants after an investigation has found probable cause to seize evidence
            """
          • Swat doesn't get called unless there is a barricade, ongoing threat

            Like some moron that caught by 'To Catch a Prevert'?

            If you do something and they make it illegal, and then commit that illegal act, suddenly you can get hassled by the cops. So what, your doing something illegal. Now there are ways to contest unjust laws and unconstitutional laws. If you think the answer is to just violate the law instead of taking care of it properly, then you deserve what you get.

            That is the way to contest the law.

            • Like some moron that caught by 'To Catch a Prevert'?

              I'm not sure what your saying here.

              That is the way to contest the law. Feeling lucky?

              No, you challenge it in court. that is the way to contest it without breaking the law.

              1. Lie detectors aren't admissable in a court and 2. presumption of innocence.

              Yep, that's my point. There are reasons why things we already have availible isn't used i ways the parent described. There isn't any reason to think it would be different with this.

              Newsflash: we traine

              • I'm not sure what your saying here.

                TCAP has had the cops using swat teams to take down the perverts they entrap, even though they are, as a rule more pathetic than they are dangerous.

                No, you challenge it in court. that is the way to contest it without breaking the law.

                You have to show standing- this means you can't protest the law until you're punished for breaking it.

                • Not being able to do an activity you want to do should be standing. Just saying it is unconstitutional doesn't give you standing. But saying you are forbidden to do something you intend to do is standing.

                  Look at how they go after certain provisions of laws today. As soon as they are passed and signed into law, someone is starting the challenging process. I would admit that a good majority of laws are challenged because people were arrested for violating them. But it doesn't make it the only way to get stand
      • It will be on their shirts, or clothing from attempting to conceal it.

        You don't think that a terrorist would be able to obtain a plastic bag to hold their bomb?


      • As for false positives, it isn't likely to be a problem.

        Without knowing the false positive rate, you can't say anything about if it's a problem or not. If the rate is even 1 in 10,000, this is going to be a useless test. Airports have 10s of thousands of people going through them each day. What are you going to do when you have multiple false positives every day?
        • Re: (Score:3, Insightful)

          by sumdumass ( 711423 )
          1 in 10,000 isn't that bad for a false positive rate. But the false positive isn't conclusive evidence to anything. It is just one more way or reason to look at someone. I would be more worried about what it missed and no one looked at because it didn't go off then I would about having someone delayed an extra 20 minutes for whatever reason.

          You do realize that your 1 in 10,000 rate would only be one or two false positives a day in an airport that sees 10s f thousands of people. But I don't think this is the
          • by SL Baur ( 19540 )

            You do realize that your 1 in 10,000 rate would only be one or two false positives a day in an airport that sees 10s f thousands of people.

            Only smaller airports see that level of traffic and the USA has many airports. It is a ludicrous figure for a nation that used to preach "innocent until proven guilty".

            Comparing a nation with a real terrorist problem like the Philippines which has three "major"[1] airports (probably only NAIA reaches >10k passengers a day) - the Davao City airport terminal has been bombed twice[2] since 2003 and NAIA domestic terminal bombed once. I'll leave out the SuperFerry bombing a few years back which was blamed

            • Only smaller airports see that level of traffic and the USA has many airports. It is a ludicrous figure for a nation that used to preach "innocent until proven guilty".

              Innocent until proven guilty doesn't mean that you will go scott free until someone catches you red handed. It means that there needs to be a reason why they are looking at you and you need to be adjudicated before punished.

              I don't know where you think your going with this but it isn't making the effect you might think it is. if there are 1

              • It means that there needs to be a reason why they are looking at you and you need to be adjudicated before punished.

                Which means that they need PC before spraying you down. Being in the airport isn't really enough. You seem to be advocating a blanket policy, which isn't justified by the threat and would screw airports even more.

                if there are 10 false positives a day, it wouldn't be that troublesome either. Why? Because no one it suggesting using this stuff as definitive proof of wrong doing.

                No, you jus

                • Which means that they need PC before spraying you down. Being in the airport isn't really enough. You seem to be advocating a blanket policy, which isn't justified by the threat and would screw airports even more.

                  Lol.. I'm advocating nothing of the sorts. If anything, I'm only saying I can see where it would be helpful as one more part of an ongoing investigation. You know, 900 people walk through the gate but security stops 50 of them because they look mean, look like arabs or look like some one they can

                  • You might ask, why do you think that? And I would answer with, you don't need to listen to government propaganda to find this out. Al Qeada releases video often saying what they would be looking to do.

                    Whoopty do. Al Queda isn't enough of a threat to justify half the shit done in its name. They've managed one (admittedly very well done) terrorist attack and killed a few thousand. That's a month's worth of driving deaths. If we implemented the locking doors in cockpits, that'd be enough to stop repeats - w

                    • Whoopty do. Al Queda isn't enough of a threat to justify half the shit done in its name. They've managed one (admittedly very well done) terrorist attack and killed a few thousand. That's a month's worth of driving deaths. If we implemented the locking doors in cockpits, that'd be enough to stop repeats - we already had bomb sniffing equipment in the airports. The bulk of the TSA stuff is completely pointless.

                      Lol.. So should we take down the metal detectors and all because the deaths arising from shootin

                    • Lol.. So should we take down the metal detectors and all because the deaths arising from shooting in public places like court houses or hijacked airplanes are far less then the number of people that Die from car accidents?

                      Don't be a jackass. I'm saying that the security reaction to 9/11 is almost wholly innefective and that it should be scrapped. I'm also saying that Al Queda is a pissant.

                      The idea is to not let the death occur in the first place is there is something that could be done to stop them. No


          • You do realize that your 1 in 10,000 rate would only be one or two false positives a day in an airport that sees 10s f thousands of people

            The 1 in 10,000 number is just a dumb number I made up. It's totally irrelevant to whether this is a good test or not.

            Anyway, my point is really that even a 1/10,000 rate is poor evidence the person has done anything wrong. It's not even enough evidence to strip search someone when you're getting several people at each airport every day. What are you going to do at the
      • by mstahl ( 701501 )

        As for false positives, it isn't likely to be a problem. The stuff shows who the likely people are not who the person is. If you have a legitimate reason for the chemicals on you, you get to go. If you don't, then they look to see why you have it.

        Funny story... once I got put on a watch list for having trace amounts of TNT on one of my sandals. We're talking old worn-in dirty hippie leather sandals here . . . with trace amounts of TNT on them. Someone at some point probably thought the same exact thing about the little machine that sniffs around your stuff at the airport, but what happened to me is that I had absolutely no clue whatsoever how the TNT got on my sandals, much less a legitimate reason for it.

        I don't think anyone's pissed off about a

    • "Terrorists will now use gloves to make bombs."

      Yeah, in theory. Also, in theory, you can wear gloves to prevent your fingerprints from being left at the scene of a crime. Yet, in a lot of cases, they're found anyway.
  • by davidsyes ( 765062 ) on Wednesday September 19, 2007 @08:28PM (#20675261) Homepage Journal
    piss-poor detector...

    (captcha: enrage)

  • That is why... (Score:5, Insightful)

    by j. andrew rogers ( 774820 ) on Wednesday September 19, 2007 @08:35PM (#20675329)
    ...smart terrorists only use peroxide-based explosives (like the London subway bombing et al), oxidized halide based explosives (e.g. chlorate), and various other dirt cheap and ubiquitous explosives. While many of the most famous explosive chemistries might be subject to nitrate tests, the range of explosive chemistries that have been used at various times is far more diverse than nitrates. First World War mortar explosives are as dangerous today as they were back then, even if some of them do not contain nitrates.

    The fixation on the detection of nitrate and related chemistry is a bit of a blind spot in explosive detection technology.
    • I think they are focusing on IEDs and what they have to work with presently i Iraq and so on.

      While I would agree that it would create a blind spot in the detection, we are having serious problems with a certain types of IEDs right now. Even if we are 10% closer to detecting and punishing those behind the stuff, that is 10% further then yesterday. And I think that is a good thing.
    • The fixation on the detection of nitrate and related chemistry is a bit of a blind spot in explosive detection technology.
      On who you're trying to sell it to.
  • by Anonymous Coward on Wednesday September 19, 2007 @08:49PM (#20675467)
    In the UK, the Birmingham Six [wikipedia.org] were falsely imprisoned for 16 years (one chap died in prison) largely because of the Griess test [wikipedia.org]. The trouble is, anything nitrated will give a positive. The playing cards the men had been using on the train when they were arrested were probably what set it off. Ping pong balls certainly would. Imagine Forrest Gump in the Twenty First Century, "And then I met the President again, then they tasered me, then I went to prison for life." The Griess test is now completely discredited. Its re-introduction would be on a par with admitting polygraphs, or examining chickens' giblets as evidence, whether it's packaged as an aerosol or anything else.
    • Well said, and even if it didn't yeild false positives, spraying half of the population of Palestine or Iraq yellow will obviously help us along the road to peace.
  • by feepness ( 543479 ) on Wednesday September 19, 2007 @08:51PM (#20675485)
    I think labeling people as terrorists because of their color is just wrong.
    • by antic ( 29198 )
      Kid busted spraying graffiti: "Sir, I was just helping in the hunt for terrorists!"
  • by jo7hs2 ( 884069 )
    Is this going to be another GSR-like useless test? Because that's just what I wanted for Christmas.
  • by Looshi ( 1038712 ) on Wednesday September 19, 2007 @09:23PM (#20675761)

    ...when your first thought is the effect on the rights of the bomb makers.

  • marking spin (Score:4, Insightful)

    by drDugan ( 219551 ) on Wednesday September 19, 2007 @09:23PM (#20675763) Homepage
    someone got the marketing spin engine revving to 50K RPM today:

    "that can identify people suspected of making or planting bombs."

    Bullshit. Using the spray may detect a chemical, (not people) which then people may use to suspect one another.
    Big difference.

    • Re: (Score:2, Insightful)

      by E++99 ( 880734 )
      "that can identify people suspected of making or planting bombs."

      Why would you even need a spray to identify people suspected of making or planting bombs? If they're already suspected, then surely you know which people you suspect! Why is precise writing so hard for professional writers??? How about this -- It identifies people who have been in recent contact with certain types of possible explosives residue.
  • Urea nitrate? And this article was from the "spray-the-terror-away" department?

    Why, that should have been from the "pissing-the-night-away" department. Any Chumbawamba fan should have thought of it.

    "I get blown up, I get up again,
    And you're never gonna keep me down
    I get blown up, I get up again,
    And you're never gonna keep me down..."
  • by argent ( 18001 ) <{moc.agnorat.6002.todhsals} {ta} {retep}> on Wednesday September 19, 2007 @09:33PM (#20675863) Homepage Journal
    The test for iron to tell if someone has handled a gun, or a grenade, or ... a wrench, or a wrought-iron railing, no?
  • This guy [okstate.edu] showed us a clear liquid that turns bright blue when it reacts with peroxide based explosives about four years ago in my chem for Engineers class. If this stuff is so useful, I kind of wonder why THIS chemical hasn't come into popular use. It was also sprayable, non-toxic, etc etc. He was always bragging about meeting with generals and executives to discuss it.

    Makes me wonder why they're bothering to develop more when they're not coming into widespread use.
  • *sprays person's hands*
    Is it red? Is it red?
    Is it- BOOM!
  • Try new "Bombs Away!" anti-fumblementalist aerosol.

    Just spray in the air and terrorists fade away like bad gas.

    New, from Ryan Industries.
  • The chemical turns from yellow to bright red when it comes into contact with urea nitrate, an explosive residue that may be left behind on the hands of someone who has handled an improvised device

    ..... or someone who has planted up some flower bulbs, smoked a cigarette, handled a pet, inserted or removed a white 13 amp plug, played a few games with a brand new pack of playing cards, been to the toilet and not washed their hands, touched a formica table top, or done any of a million and one other innocuous

  • Go down to your local airport. Pick something that lots of people will handle, say the luggage trollies, or the paper towels in a bathroom, and sprinkle with urea nitrate. Leave before the avalanche of false positives at the security checks.
  • ...And yet I have not heard anyone say anything about being caught red handed. :p

    (Although on that note, I did not scroll through ALL the responses for this story)
  • As someone who has had kidney failure (now had transplant) I happen to know that there is an increase in Blood Urea Nitrate as it cannot be cleaned out by the failed kidneys.

    This will escape through sweat glands and will show up as a positive test for "explosive residue". hmm somewhat stuck there. Honest, I'm on dialysis guv.

    p.s. Osama Bin Laden also has kidney failure. How they going to cope with that one!

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