Re: Carbon Monoxide Poisoning in the home
From: wpenrose@interaccess.com (William R. Penrose) 
Date: Jul 20 1995
newsgroups: sci.misc

In article <3ui1cg$9b@news.iastate.edu> dhanwada@iastate.edu (C Dhanwada)
writes:

>As I recall cyanide (KCN) also kills due to same reason: KCN has a
>greater affinity than oxygen to bind with the iron atom in hemoglobin.

Cyanide actually doesn't bind to hemoglobin at all.  It binds to the final 
enzyme in the mitochondrial electron transport chain, cytochrome oxidase.  
There isn't much cyt ox in the body, so only a little cyanide is needed.  The 
antidote, in fact, is to take or breathe a little nitrite which reduces the 
iron in hemoglobin (methemoglobin), which *does* bind cyanide, and competes 
with the cyt ox for the circulating CN.  With large doses, though, CN kills so 
quickly that there is not time for the antidote to help.

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives,sci.chem
Subject: Re: Dynamite and gasoline
Date: 8 Nov 1995 07:27:23 GMT
Organization: Consulting Chemist
Lines: 23

In article <47l9ch$k39@news.sas.ab.ca>, mwo@freenet.edmonton.ab.ca () says:

>Acutally you can, Cyanide has a very pungent odour to it when it gets to 
>lethal levels.  I work with it a non lethal levels and HCN still stinks...

The problem is that about 15 percent of the people 
cannot smell cyanides at all. It is apparently a genetic
trait. I can smell them, but I have been blacked out 
momentarily by a whiff I would not describe as pungent.

Even as a non-smoker I occasionally used cigaret smoke
in my mouth as an early warning detector for loose
HCN, (CN)2 and CNX (X= halogen) in the lab. I had a friend
who got a whiff one day and awoke in the hospital. 
Thereafter he became extremely sensitive to and aware of
the cyanide which occassionally rose from our communal
drain system. One day he was using a wrench on a small 
steel HCN cylinder when the valve broke off and he was 
doused with the liquified gas. The poor guy ran in circles
on that roof for a long time to keep a headwind blowing
until he was sure it had all vaporized and been blown away.


Jerry

From: REMOVE_THISdwilkins@means.net (Don Wilkins)
Newsgroups: rec.crafts.metalworking
Subject: Re: isocynate vapor: any experts out there?
Date: Fri, 28 Aug 1998 03:14:24 GMT

On 26 Aug 1998 23:59:10 -0700, Bill Westfield
<billw@flipper.cisco.com> wrote:

>Doesn't Hydrogen Cyanide have a recognizable "almond-like" odor?  (I wonder
>who figured that out!)

Yes it does but that "almond-like odor" is in fact hydrogen cyanide
contained in the almond.

One pound bottles of potassium cyanide were common in the lab and
every time you removed the cover you got a sniff of the "almond-like"
odor.

No big deal if you just get a small sniff. Bigger sniff could be a big
problem. One treats it with respect.

It is also used in the heat treatment of steels. (just to stay on
topic)