Is copper oxide as poisonous as copper?

Question

How easy is it to get poisoned from copper? In powdered form it is easily lethal if ingested, with similar consequences to that of arsenic... but what about water running through pipes? Does it spall off into the water as it passes though? It would seem that copper pipes that have oxidized inside must more readily spall the oxide into the water.

The reason I ask- I'd like to buy a vintage coffee grinder- but the hopper is copper, which is oxidized to almost green. My oily coffee beans would be in contact with this surface all the time. Does this pose a health hazard? Is it any less hazardous than non-oxidized copper?

I drink a lot of coffee- and I am usually fairly committed to the household appliances I invest in- I don't want to wind up a mad hatter in a few years!

Answer 1

EVERYTHING is poison, it's a question of quantity.  Also there is some, however small, amount of everything in everything.  Arsenic is present in water but at very low levels it is not a problem.  Many poison metals are nutrients in small quantities.  Take zinc, which is illegal for industries to discharge into the sewer but is used to prevent colds.

Copper oxide does not spall and copper pipes are used just because they don’t corrode. Copper will normally dull (patina) and if it were bright that would indicate that some was being rubbed off in use. If the corrosion is green it’s not the oxide.  I’d scrub it out and hen figure that anything left is going to stay there.  Copper is often used in food contact applications such a candy making.  Strohs beer (not made anymore) was advertised o be made in copper kettles and I understand it was about 6ppm copper.  Most city sewer plants won’t let you discharge more than 1-2 ppm in the sewer!  I drank a lot of Strohs and I’m not dead yet.  I’m thinking alcohol and coffee aren’t good for us, so forget about a little copper.

As for the Mad Hatter that was mercury from it being used as a preservative in the beaver fur used to make the hats.  SOME mercury is in the water and air but again, how much makes ALL the difference.