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manganese worries

updated tue 28 apr 98

 

amy parker on sun 26 apr 98

All this talk about manganese is worrying me. I have bought several bags
of speckled and "black" clay to experiment with. The specks are granular
manganese, and the "black" is i guess more finely powdered. NONE of the
clay bodies are labeled as Toxic or even Hazardous by the makers in their
catalogs, so, I have been using these freely. SHOULDN'T LABELING BE
REQUIRED???

I have two cats & two kids. The kids, 10 & 12, are learning to throw. They
are messy. The cats, (Nikki,"Mr. Inspector") in particular, are very
curious. Nikki already has cystic kidney disease, and i found him sipping
the throwing water the other day, PLUS, I had left a "black" bowl on the wheel
head the other day & came back to find the side caved in (altered) with much
fur embedded. Apparently, he had come to check out the bowl & put his face
over the edge. I have two same-colored Himalayans, so I had to round up both
to find the dirty one. I washed him off thoroughly, I THOUGHT, and later found
a fine black powder in the bottom of his water bowl. Maybe he got a drink &
rinsed some off before I caught up to him.

SO - I guess I won't be buying any more clay with manganese in it!!! But,
do I need to consider chelation for the cat ;-)? And what about all the residual
film & splatters from the "black" clay? It was fun, but the end result looked
like I had poured Hershey's syrup all over the place & was a real Bitch to
clean up!!! It is still all over one of my favorite T-shirts :-(((.

Amy in Greater Atlanta where I am turning the goldfinches the brightest ever
and also the Indigo Buntings so the rest of you can enjoy them for the summer.
amy parker Lithonia, GA
amyp@sd-software.com

Dannon Rhudy on mon 27 apr 98


Amy, manganese is really toxic, although in theory the granular
form is too large/heavy a grain to be floating around. The
problem there is that, once in the form of studio dust, it is no
longer granular.

Studios in general are very hazardous to cats, because they
wash their feet with their tongues. There is no way to prevent
them picking up small amounts of whatever is in your glazes and
clays.

For children, it would definitely be best to let them learn to
throw with stoneware or other clays that do NOT contain manganese.
They mayn't wash their feet with their tongues, but you've already
noticed that any clay they are working with gets all over their
skin, face, hair, etc.

For myself, I permit no manganese in the studio; there are other
ways to get speckles (try shaving a little rust into the clay or
the glaze, for instance).

Don't get too excited about what's been and gone. But- manganese
is a very toxic heavy metal, absorbed through the skin as all
heavy metals are, breathed in as dust in the air, carried on
clothes/skin/hair/shoes into the house. In my opinion, it would
be best to use something else.

Get a new favorite tee shirt.

Regards,

Dannon Rhudy
potter@koyote.com

----------------------------Original
message----------------------------
All this talk about manganese is worrying me. I have bought
several bags
of speckled and "black" clay to experiment with. The specks are
granular
manganese, and the "black" is i guess more finely powdered. NONE
of the
clay bodies are labeled as Toxic or even Hazardous by the makers
in their
catalogs, so, I have been using these freely. SHOULDN'T LABELING
BE
REQUIRED???

I have two cats & two kids. The kids, 10 & 12, are learning to
throw. They
are messy. The cats, (Nikki,"Mr. Inspector") in particular, are
very
curious. Nikki already has cystic kidney disease, and i found him
sipping
the throwing water the other day, PLUS, I had left a "black" bowl
on the wheel
head the other day & came back to find the side caved in (altered)
with much
fur embedded. Apparently, he had come to check out the bowl & put
his face
over the edge. I have two same-colored Himalayans, so I had to
round up both
to find the dirty one. I washed him off thoroughly, I THOUGHT,
and later found
a fine black powder in the bottom of his water bowl. Maybe he got
a drink &
rinsed some off before I caught up to him.

SO - I guess I won't be buying any more clay with manganese in
it!!! But,
do I need to consider chelation for the cat ;-)? And what about
all the residual
film & splatters from the "black" clay? It was fun, but the end
result looked
like I had poured Hershey's syrup all over the place & was a real
Bitch to
clean up!!! It is still all over one of my favorite T-shirts
:-(((.

Amy in Greater Atlanta where I am turning the goldfinches the
brightest ever
and also the Indigo Buntings so the rest of you can enjoy them for
the summer.
amy parker Lithonia, GA
amyp@sd-software.com

Stuart Ridgway on mon 27 apr 98

Hi Amy
Extracted from the 63rd edition of the Handbookl of Chemistry and
Physics, page B-25, the section on the elements:

"... The permanganate is a powerful oxidizing agent and is used in
quantitative analysis and medicine. Manganese is widely distributed
throughout the animal kingdom. It is an importantant trace element and may
be essential for the utilization of vitamin B1. Exposure to manganese
compounds as dust, fume, and compounds should not exceed 5 milligrams/cubic
meter for even short periods because of the toxicity of the element in
larger quantity."

Not too much help. A little is essential, too much is poisonous.
Flashlight batteries contained lots of manganese dioxide, and I, at the
tender age of ten or eleven, disassembled many of them to retrieve the
carbon rods that were the central element and if I got manganese poisoning
I didn't know it. I also remember doctor provided little pills of potassium
permanganate that were dissolved in water to be applied to fungus
infections, but were not intended to be taken internally.
In chemistry lab at college when we made chlorine by adding Hydrochloric
acid to manganese dioxide, we were instructed to be very careful not to
breathe the chlorine, but no particular precautions were demanded in the
handling of the manganese dioxide.

I wish I could tell you where to get more modern and detailed
information.

Stuart Ridgway





>----------------------------Original message----------------------------
>All this talk about manganese is worrying me. I have bought several bags
>of speckled and "black" clay to experiment with. The specks are granular
>manganese, and the "black" is i guess more finely powdered. NONE of the
>clay bodies are labeled as Toxic or even Hazardous by the makers in their
>catalogs, so, I have been using these freely. SHOULDN'T LABELING BE
>REQUIRED???
>
>I have two cats & two kids. The kids, 10 & 12, are learning to throw. They
>are messy. The cats, (Nikki,"Mr. Inspector") in particular, are very
>curious. Nikki already has cystic kidney disease, and i found him sipping
>the throwing water the other day, PLUS, I had left a "black" bowl on the wheel
>head the other day & came back to find the side caved in (altered) with much
>fur embedded. Apparently, he had come to check out the bowl & put his face
>over the edge. I have two same-colored Himalayans, so I had to round up both
>to find the dirty one. I washed him off thoroughly, I THOUGHT, and later found
>a fine black powder in the bottom of his water bowl. Maybe he got a drink &
>rinsed some off before I caught up to him.
>
>SO - I guess I won't be buying any more clay with manganese in it!!! But,
>do I need to consider chelation for the cat ;-)? And what about all the
residual
>film & splatters from the "black" clay? It was fun, but the end result looked
>like I had poured Hershey's syrup all over the place & was a real Bitch to
>clean up!!! It is still all over one of my favorite T-shirts :-(((.
>
>Amy in Greater Atlanta where I am turning the goldfinches the brightest ever
>and also the Indigo Buntings so the rest of you can enjoy them for the summer.
>amy parker Lithonia, GA
>amyp@sd-software.com
>