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cobalt leaching at c

updated fri 6 mar 98


Monona Rossol on thu 5 mar 98

-------------------- Forwarded message ----------
Date: Wed, 4 Mar 1998 08:57:12 EST
From: Numo Jaeger and Michael Miller
Subject: Re: Cobalt leaching at cone 10
---------------------------Original message----------------------------
Hi Craig,
Thanks for the reply! Do you know of a source book or article where I can
read further on leachability levels of cobalt (and other metals) and what
is harmful?

I was thinking and curious about healthy amounts of trace metals and how
this relates to clay pots and the leachability issues.
For instance: cooking in cast iron ware is supposed to be healthy for
you because of the small amounts that the pot or cookware releases.
What is the threshhold level of cobalt for humans? What amount is ok if any?

Numo Jaeger
Studio One Art Center
365 45th Street
Oakland, CA 94606
This is such important a question!

Even iron, for example, in cookware can be a problem for health. The natives
of certain areas in Africa who use iron cooking pots develop a form of
hemochromatosis from excessive iron in the diet. I even know of a lawyer in
Chicago who developed this disease from his wife's iron-glazed coffee cups!

The answer to how much of any metal should leach out of ceramicware is still:
as close to ZERO as possible. The public--your customers---are getting their
minerals from their diets and dietary supplements. They do not need ANY
uncontrolled sources of metals and minerals--that are not as PURE or are in
FORMS THAT ARE NOT AS GOOD FOR YOU as those in dietary supplements--coming
from their ceramics.

Monona Rossol, industrial hygienist
Arts, Crafts and Theater Safety
181 Thompson St., # 23
New York NY 10012-2586 212/777-0062