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degusse toxic?

updated thu 31 jul 97


Lesley Alexander on tue 15 jul 97

I had to ask! Monona Rossol's reply to my direct email about
encapsulated cadmium pigments (DeGusse) seems worth repeating. Now I wish
someone would test these pigments under some clear glazes, and mixed in
glazes, and mixed in clay under clear glazes. Sure would like to use those
pigments on plates!

"The only tests of the encapsulated cadmium pigments I've seen were for
ingestion of the powdered incapsulated pigments. And they were very poor
studies. Besides, the bioavailability of the powdered glaze is absolutely
unrelated to the leaching characteristics of the fired glaze.

Did you see the new lead and cadmium decal and decoration standards for glass
and mugs? They are going to spill over into ceramics, mark my word. FDA is
planning to treat both lead and cadmium as food adulterants at even lower

In any case, you just can't rely on any of the hype about encapsulation.
There are too many variables in application and firing. Any ceramicist that
uses glazes that contain lead or cadmium on a food surfaces has to have a
regular documented laboratory testing program. People using lead and cadmium
on food ware shouldn't *speculate.* They must test and *know* what their
ware leaches."

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