Murder by nitrogen

“The older bald guy” would have been Dr. Roy Walford. No one by the name of Story Muskgrove or anything similar was in either of the two biosphere 2 crews.

I don’t think this is a particularly good way to kill someone. I don’t think I could be successfully prosecuted as an accessory, either. What if we were talking about which kitchen knives we liked to cook with?

Concentrations of oxygen, carbon dioxide and nitrogen can be measure by electrical probes. They had a few in the lab where I was doing my biomechanical engineering thesis, but I couldn’t give you the details.

okay, I’m going to kill you via the use of nitrogen

sure, no problem, I’m just going to put you in a relatively air tight room and flood it with nitrogen in order to drop the concentration of oxygen below the level needed to sustain life

Sure peace, no problem, excuse me as I get started on the room. Know a good place to buy a large amount of nitrogen?
I’d also like to hear your spin on things sense you’ve decided that all of our opinions on this subject are wrong.

Ain’t easy, is it? We don’t like to close threads very much. When we do so, we weigh factors including “how likely is someone to actually do this” and “how helpful are the responses here.”

Not only do I trust that matt will not actually try to kill someone by nitrogen poisoning, I am confident that lurkers will also not take this as inspiration to do anything of the sort.

Accordingly, I am leaving this thread open.

But if anyone kills anybody with nitrogen poisioning from ideas in this thread there’s gonna be big trouble!

And yes, insulting fellow members is still prohibited in this forum.

Hehehehe… If it were to happen, a truly dedicated Doper would post the results, whether or not the person noticed it occuring, and how long it took…

Personally, if I’ve got access to a bunch of Nitrogen, I would just mix up some Ammonia, and try for a big ol’ ANFO bomb.

But that’s me, King of the Bodycounts!!

I’d seen old newsreel-class footage of CO[sub]2[/sub] and N[sub]2[/sub] tests they made on dogs in the 50’s. They were testing for a number of things, but the key one was what to watch out for in high-flying fighter jets of the day.
The footage showed that going from 1/2% CO[sub]2[/sub] in a sleeping dog would wake him up with reddened tissues. Conversely, going from 80% N[sub]2[/sub] to 90% would put him to sleep and eventually kill him.

OK, Man, since now on, I’ll trust you experience and judgement more and will post no more cautions. Nobody’s gonna kill nobody.
I’ll actively participate in the thread instead.
I can think of many “cons” in nitrogen killing. Despite its relative availability (compared, say, to highly poisonous halogen gases), I have never heard of “nitrogen” murder. As a matter of fact, liquefied or compressed gases are not popular in this country as murder weapons. Even ubiquitos, accessible heating gas. On the other hand, numerous “perfect” or hardly traceble ways to kill a human being are known. A skillful executioner is hard to find, though.

Time to come clean:

I’ve gotten into the habit of watching Diagnosis Murder every day when I eat my lunch. I’m not proud of it, okay? But that’s British daytime TV for you. Gets me thinking along murder mystery lines, anyway.
(My question a couple of weeks ago about whether you could be charged with murdering a corpse was lifted from the show, although their scenario was rather different.)

The nitrogen question stems from the use of nitrogen in my lab, which is usually bubbling through solutions all day long. Nobody’s going to use our nitrogen tanks to kill anyone though - they’re five feet tall, weigh 250 lbs and hiss like hell if you open the regulators up. (Well, I guess you could drop them out the window on someone!) We have quite enough cyanide and thallium for the truly murderous to indulge themselves.

Peace: from your answers in the neck-cracking thread, I’m guessing you have some expertise in forensics and/or medicine. I’d be grateful if you could elaborate on the mistakes in the previous posts in this thread?

Mixing carbon dioxide in the air at the same concentration as in exhaled air would still cause acidosis, since the levels of carbon dioxide would still be higher in the blood due to the hypoxia. In fact, if anything it would diffuse out of the lungs less quickly.

I was a bit worried, but now I’m releived that we don’t have to worry about you killing anyone with nitrogen.

Thanks for clearing that up.

I knew that name seemed familiar, Story Musgrave is an older, bald NASA astronaut. AFAIK he was never associated with Biosphere 2 let alone did he ever live inside the apparatus.

I think that murder via Nitrogen was the idea behind the Robin Cook book “Coma” in the 70’s. It was later made into a movie with Michael Douglas and Genvieve Bujold (spelling?). The eye-catching thing was the bodies hanging by strings in a warehouse-like environment…

or maybe it was carbon dioxide or carbon monoxide?

Dr Paprika: "Mixing carbon dioxide in the air at the same concentration as in exhaled air would still cause acidosis, since the levels of carbon dioxide would still be higher in the blood due to the hypoxia. In fact, if anything it would diffuse out of the lungs less quickly."

My mistake, I was thinking along different lines. Specifically, I was thinking that lowered levels of blood CO[sub]2[/sub] would occur, since you could still breathe it out but your body would be running short of the oxygen necessary to produce more of it. So my suggestion was to prevent CO[sub]2[/sub] depletion rather than its build-up, which I’m guessing is the cause of acidosis.

donnydon: carbon monoxide was the gas used in coma. Good movie! Not so great book though. Robin Cook has some truly nasty ideas, but I don’t like his writing much.

DrMatrix: glad to set your mind at rest!

The original point seems to be mostly settled, so perhaps I can hijack the thread. I too think of wierd ideas that might someday be incorporated into crime stories/murder mysteries.

One that I had thought of before is back in my mind because of the current stunt by magician David Blaine: Will someone die if they are left in a room full of ice? Let’s say an ice floor 1 m. , 1m thick walls 5m high, with or without some kind of ice roof.

Do people that get locked into walk-in freezers (what are those, 10 degrees F?) die if they are not rescued in X hrs?

Would liquid N2 make a better murder weapon, since you could pour it/pump it (?) without it hissing like a gas and waking up the victim?

We probably see more hypothermia in Canada than in the US.

Tissue freezes at -4 degrees. When it thaws, it ain’t the same. There is some debate on how cold to keep experimental cadavers without changing physical properties.

With a central temperature below 28 degrees celsius, the old heart gives way.

A central temperature below 32 degrees celsius is dangerous. Craziness sets in (cold people remove all their clothes!) and the heart rhythms become funny.

So it depends on how long it takes for the central temperature (rectal) to go below 35 degrees celsius, which can be approximated by Newton’s law of Cooling. The rate of change in temperature is proportional to the difference between the body and ambient temperatures.

Matt, you asked you question correctly and almost answed it, too. I read about one half of the thread, then the authors began to discuss their wrong answers, I lost interest. Anyway, one does not have to know forensics to understand your scenario. Just one thing: forensic experts do no work in vacuum. Actually, the autopsy is one of the last steps in forensic investigation. The cause of death will be evident to the first officer at the sceen, the one who discovers the (compressed or liquid) nitrogen tank. In general, the case of death could be mysterious in cases of natural death.In cases of violent death police tells the medical examiner what the cause of death was, not the other way around. The medical examiner must confirm that the actual cause of death is, e.g. that the person drowned, and was not poisoned before the body was dumped in the river, etc.
In you scenario, I assume that the victim was breathing room air in a regular room. The concentration of nitrogen would probably, be ~90-95%. Therefore, the oxygen concentration would be 5-10%. This is incompatible with life. The victim will die of asphyxia, before any acidosis will develop (experts here assumed that there will be acidosis; why?). So, to answer your questions:

  1. Yes. Newcomers to Lima, Peru, cannot walk more than a few hundred yards without shortness of breath. The partial pressure of oxygen is lower there. Not exact analogy, but lack of oxygen is perceived as such (“lack of air”).
    2)Yes, they will.
  2. The autopsy findings would be those of asphyxia.

I can understand your interest in detective books and TV shows, but take them with a grain, no, with a sack of salt. They are not documentaries, their purpose is to keep your attention. They can do that.

just a followup I promised I would give info on. Yesterday per my paramedic program requirements I spent a day at OMI. I asked about the concentrations of O2 and CO2 in the blood post death.

Given you find the body before the blood has clotted…
levels of O2 would be low, levels of CO2 would be high

this is due to the fact that cellular death and death of the organism do not occur at the same time. Once apena (respatory arrest) and then caradic arrest occur the body continues to function at the cellular level. This means that the O2 reserves held in the blood get used up, CO2 is created but cannot be blown off by the lungs.

Many thanks, everyone!

**Padeye **:

Padeye, I’d be very interested in reading more about your experience (probably not in this thread).

I was never very interested in Biosphere 2, but then at the 1999 Mars Society convention I met one of the Biospherians, the attractive fortyish blonde ocean lady. She participated in a panel about colonies on Mars.

And then still later I read Roy Walford’s book The Anti-Aging Plan, which discusses many of the Biospherians’ (dietary) experiences.

So, if you start an MPSIMS or IMHO thread about Biosphere 2 from your perspective, I’m there.