I was watching The Jackle on USA today and Bruce Willis sprays some chemical on the handle of his car, then the bad guy trys to open the door but when he touches the handle he feels the chemical and wipes it off on his pants, then he dies, some white stuff starts comming out of his mouth, the whole death took about half a minute, from the time he touches the chemical till he is on the ground motionless. My question is whether or not any chemical like this really exists? It seems kinda scary? Anyone know what this was based on?
::WAG::
DMSO and any fast acting poison?
What I would question is whether such a small point of contact would cause such rapid death?
Something along the lines of the alleged CIA plot to assassinate Castro with a poison-impregnated wetsuit might deliver enough poison through the skin to work very rapidly by sheer virtue of the area of contact, but I’m not so sure about door handles.
What about the poisoned Dress of Death in Elizabeth?
From an about.com website, I can go back and find it if you need it.
NERVE AGENTS
Tabun (GA), Sarin (GB), Soman (GD), GF, VX - The most toxic of the known chemical agents. Nerve agents are extreme hazards in their liquid and vapor states and can cause death minutes after exposure.
(Disclaimer: I have not seen the scene in question, so I haven’t had a good look at the symptoms. Hollywood probably screwed them up anyway.)
Well, there’s hydrocyanic acid, which exhibits dermal toxicity with symptoms of cyanide poisoning (including increased salivation and shortness of breath, which might make for slightly foamy white spit). It’s unlikely that he could have gotten enough of the stuff into his blood stream through his skin to kill him, though.
The nerve agents waxteeth mentions are far more deadly (VX has an estimated skin LD50 of around 10 mg in humans), but even inhalation of the gas takes several minutes to kill–skin contact can take hours. I’m not sure it would produce the foaming-at-the-mouth symptom, either.
AFAIK, no existing contact poison will produce the effects shown in the movie. LifeWillFall, I think you can relax…at least until you catch a whiff of bitter almonds…
Fun facts: The plant from which tapioca is made, Manihot esculenta contains hydrocyanic acid, which must be removed in the processing of the plant.
I used to work for a company that manufactured chemical warfare agent test kits for the US military. At one point we were working on developing a kit to test for the presence of T2 toxin, also known as “Yellow Rain”. Yellow rain may or may not have been used during the Vietnam War, depending on who you believe.
I’m not sure about the number given above for VX, as LD50 are usually shown as mg per kg body weight. The LD50 oral for T2 is 4mg/kg in rats. No LD50 dermal is shown, only that it is fatal via dermal exposure (source: [Merck](http://mycoherbicide.net/HEALTH/MYCOTOXINS/index.htm#T-2 Toxin)). At the time I was working with this, I was told that T2 was far more toxic via dermal exposure than oral, as the acidity of saliva destroyed some of its activity. The link I provide shows a subctaneous (injected beneath the skin) LD50 of half to one quarter the oral for animals tested, so it may be true. I would guess that it might be possible for T2 to have an affect similar to what you saw in the film. I don’t know too many people who can prove otherwise, anyway. 
We had VX in the test lab (an amount too small to kill even one person, huge security measures anyway) and I seem to recall foaming at the mouth as a symptom of nerve gas exposure. No idea what the symptoms of T2 would be though.