A much revised question I’ve been mulling over for awhile: what would chemical weapon exposure do to a corpse?
(And, granted, right off the bat, the sheer variety of different chemical agents in the world would make this question something with no single answer)
So, say you take a man who suddenly has a heart attack, and keels over dead. An hour later, you spray the corpse with VX. If you autopsied the body later, would it look like the guy had died or been injured by the nerve gas while alive, or just be a pile of inert dead meat covered with poison? And—to record the obvious, if nothing else—what about other agents, like mustard gas, chlorine, etc.?
One thing I can say with certainty is that the poison may be absorbed through the skin, but it won’t be inhaled or circulated. That leads me to think that nerve, blood, and respiratory agents would essentially be physiologically inert. As for blister agents, I’m not sure. Certainly they would damage the skin tissue. Blistering depends on fluid moving thru the lymphatic tissues via osmosis and passive pressure, IIRC, so I will guess there might be some of that response on an extremely recently deceased corpse, but the likelihood of that would drop off very rapidly if it even existed at all.
Now, now, lissener…that’s just the kind of scenario my question hopes to prevent.
And—by my notes, nerve agents like VX or Sarin can actually absorb through the skin, so you wouldn’t have to inhale them to be affected. But again, I don’t know if that makes any difference when the “victim” is still just a side of dead meat.
Aaaand…my 7,000th post, over 9 years on the SDMB. “And the crowd goes wild.” [sub]“Yaaaaaay.”[/sub]
This is just based on my reading and not on any experience with the dead or (undead). I am pretty confident in my answer though.
During an autopsy, a coroner would definitely be able to tell whether a poison was injected, sprayed, etc, onto a body before or after death. A persons circulatory/respiratory system, while alive, would have carried the poison through the body in a way that a corpse would be unable to. Even if the toxin still damaged the tissue of a corpse, it would not damage it in the same way, because living tissue would react to the damage in some way that could be easily detected.
According to wikipedia, nerve agents work by blocking the neurotransmitter which tells muscles to relax, so when a person moves a muscle, the muscle wants to keep moving and every little move builds up into violent spasms. I would think this would cause muscle damage which would be noticeable during an autopsy. Mustard gases actually bond to DNA and kill cells, which I would think also would be noticeable.
Unless it was very quickly after death there wouldn’t be any ATP around to power the muscles. Without that the muscles won’t do anything with or without neurotransmitters. As well, without blood flow, the nerve agent might seep into the skin but it won’t travel very far.
PS It’s my understanding that nerve agents block acetylcholinesterase which breaks down the neurotransmitter acetylcholine. So, they don’t block something that makes muscles relax; they prevent the breakdown of a neurotransmitter that makes muscles contract.
Basically, that’s it. Taking the example of persons removed from a fire, those who were alive when the fire took place will have elevated bloodstream CO levels, and perhaps soot in the upper airway, whereas a person who had died beforehand will not display those signs.