On Thu, 07 May 2009 13:07:15 -0500, spaco
wrote:

Uh-oh. I should be dead from the copper water lines.

Pete Stanaitis
------------------

Hi Pete, water-soluble copper *ions* (give a blue or blue-green
solution in high enough concentration) are indeed poisonous. Copper
*metal* water lines are usually no problem because copper is pretty
inert as metals go (tin is even more so). That's one of the reasons
copper is so great for plumbing.

But if the fluid in the copper metal is sufficiently acidic, small
amounts of copper ions can be formed. At low concentrations there's a
nasty metallic taste to the water. Higher concentrations are
doubleplusungood.

This points to a universal truth: a metal (or nonmetal) in its
*element* form is radically different in both physical and chemical
properties from the same element in a compound or in ionic form.
Potassium and sodium (ions) are both necessary to life, but if you
swallowed either metal, life would be....interesting. And quite
short.

OTOH, a child may swallow a steel ball bearing with little hazard
apart from an unusual subsequent bowel movement. But iron poisoning
(from supplements, ferrous ions) is one of the leading causes of death
among young children.

Best -- Terry
....sorry about that, I can't help trying to teach...