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Aerosol Spray to Identify Bombing Suspects
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."
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..)
liqbase
Bomb makers or maybe farmers who handle fertilizer? I don't envy being a false positive in Iraq.
Jherico
What can the average user can do to ensure his security? "Nothing, you're screwed"
zillion dollar spray defeated by less than a cent disposable rubber gloves.
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...
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
Terrorists will now use gloves to make bombs. Innocent people will be falsely identified as being a terrorist.
Mission accomplished!
Knowledge is power. Knowledge shared is power lost.
piss-poor detector...
(captcha: enrage)
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
...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.
In the UK, the Birmingham Six were falsely imprisoned for 16 years (one chap died in prison) largely because of the Griess test. 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.
I think labeling people as terrorists because of their color is just wrong.
I recall that troops in Iraq had already started using silly string to detect IED's.
I wonder if a light spray of this stuff would make a hidden IED stand out as a bright red spot?
And perhaps with red trails marking how it arrived and where the people who delivered it went when they left?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
...when your first thought is the effect on the rights of the bomb makers.
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.
The test for iron to tell if someone has handled a gun, or a grenade, or ... a wrench, or a wrought-iron railing, no?
Quote "When was the last time anyone heard about an ANFO bomb going off somewhere anyway?" Depending on the minesite, from once a week to twice a day. Ammonium Nitrate(urea) and Fuel Oil explosives are the backbone of the industrial explosives. There are legitimate uses for explosives, and legitimate uses for ammonium nitrate. A chemical sensor that detects firearm propellants would be more useful for finding criminals - except we are talking about the USA and its miltiary adventures anyway. Just because I work around explosives, and have a beard, does not make me a bomb hurling radical.
Big Brother watching us has got to be better than us having to watch Big Brother
*sprays person's hands*
Is it red? Is it red?
Is it- BOOM!
You have got to be kidding me!!! Laws are not made to oppress, but because we, I say WE have seen in the past where someone or something infringed on someone else's rights and caused harm to innocents... Laws are placed for that not to happen... In the free society you speak of I would be allowed to come over there and kick the hell out of you and expect no consequences, or purchase the high explosives that I want and create a crater of glass around you!! I'm not even saying you are wrong but the utopian society you speak of will never exist we need laws to keep control of the idiots down the road and prevent future crimes... I do however have a problem with you thinking that it is a miniscule threat, PEOPLE dieing is not very miniscule... the false positives are worth it... if it saves 15 or 20 American's lives it will be worth it.. You call this a "witch hunt" it's not a witch hunt it is a serious problem.
Touchy subjects I know but worth a thought... Would you like to know that every postman could get their hands on high explosives? Could you imagine what would have happened if the kids in Columbine could have gotten their hands on high explosives?
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 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 a breathalizer test shortly after pumping ventalin (for asthma) will often result in a false positive?
My friend heard this and decided to test it with a police officer (first by passing the test, then by puffing and taking it again). They were both quite surprised at how much it skewed the reading. The officer basically stated he'd never heard of such a thing, but he'd definitely keep it in mind and pass it along to others for future reference as in a situation where he had not watched her puff and taken the earlier reading my friend would have been on her way down to the station on DUI charges.
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 mollecule after stealing a nitrate anion from _any_ nitrate whatsoever.
It could be that other mollecules don't give their nitrate as gladly as urea nitrate, or whatever. Again, I don't know enough chemistry to rule that out.
But unless I forgot chemistry completely, _any_ salt will split into a number of ions in a solution. Heck, even water doesn't stay H2O, a number of mollectules split into HO- and H3O+ ions. Ph 7 is basically just the equilibrium point for that mix.
So basically even if you handled potassium nitrate for your orchids, or made a sandwich with ham cured with that (preservative E252 _is_ potassium nitrate), or just are a chain smoker (tobacco is quite commonly treated with it too), or made a model rocket recently, etc, etc, etc... you'll have plenty of nitrate anions on your skin for this thing to bind to. Heck, it's increasingly used in toothpaste too.
And that's just one nitrate. Another common one that comes to mind is ammonium nitrate. Ok, so that one _can_ be used for an ANFO bomb, but is also used by the ton by farmers and even by miners.
So I'm, you know, _curious_ what their miracle aerosol does in the presence of those. Did they spray it on a slice of cured ham and it _didn't_ turn purple, for example? Did they check it on ammonium nitrate too? On a pingpong ball? Basically which nitrates _does_ it react with, and which not? Because again, my uninformed interpretation of their drawing is that it would react with any nitrate whatsoever.
A polar bear is a cartesian bear after a coordinate transform.
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)