At 8:22 PM -0400 5/19/02, Jim L'Hommedieu wrote:
>Huh? Are you saying that because our bodies produce a substance, it
>therefore can't be a poison? Our digestive system uses some mighty powerful
>acids (sulfuric if I remember right) but you don't want your children
>washing their eyes with stomach acid! Likewise for ammonia. Ammonia is in
>horse urine, right? That stuff will dance all over lung tissue. Or did I
>misunderstand?
Yes. The above examples are of corrosion, not poisoning. The body does not
produce sulphuric acid, it's hydrochloric acid that is generated in the stomach.
The question is not if you would want somebody to wash their eyes with stomach
acid -- of course not. The question is what would happen if they by chance got
some in their eyes. It has to have happened that many a sick child got some
vomit into their eyes. I bet it hurt, but I've never heard of a child being
blinded or even damaged by such a thing. And the problem will come from the
digestive enzymes activated by the hydrochloric acid, not from the acid itself.
If on the other hand, someone drank stomach acid, at its normal concentration,
exactly nothing would happen, though it would taste very sour. As noted
before, if concentrated enough, these chemicals are corrosive, but it does not
follow that they are poisons when dilute enough that they don't chew a hole in
something.
Another common chemical that's dangerously corrosive and yet not poisonous is
sodium hydroxide, also known as lye. Sodium hydroxide reacts with the
hydrochloric acid in the stomach to yield sodium chloride (ordinary table salt)
and water. People (usually toddlers) that eat lye suffer because their
esophagus and perhaps stomach is terribly burned, but are not poisoned. Next
time you are in the grocery store, read the text on a can of lye. One of the
standard uses is to "sweeten" slops fed to swine. "Slops" is table scraps,
food waste, etc that's been fermented to soften it up, but it becomes acid in
the process. Lye (sodium hydroxide) is then added to neutralize the acid,
making the slops palatable to the pigs.
By the same token, many real poisons are tasteless and non-corrosive, don't
even upset the stomach, and are all the more lethal for it. For instance, the
lead oxide that used to be used in white oil paint reportedly tastes sweet, and
arsenic trioxide is tasteless. Remember Arsenic and Old Lace?
Joe Gwinn
>----- Original Message -----
>From: "Joe Gwinn" <joegwinn@xxxxxxxxx>
> > This may seem strange, but Hydrochloric acid (the principal ingredient of
>tinners flux) is not a poison. How can I be so sure? Because our own
>bodies make it, in the stomach. Likewise, ammonia is not a poison, it's a
>normal byproduct of our protein metabolism. These are corrosive if
>concentrated enough, but although unpleasant they pose exactly zero threat
>when dilute.
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