Karl P. Platt on sat 10 nov 01
This is one repost concerning the use of BaO in ceramic glazes. I'm disheartened to see that discussion on this topic remains so poorly resolved
and would suggest that half-truths and nonsense prevail over any meaningful discussion of the topic.
A single fact (of many) needs to be reiterated. There is no history anywhere of anyone ever being physically compromised for having consumed food or drink from a BaO bearing Glaze.
I repeat never, ever, anywhere.
I don't have time to discuss the use of barium in any serious way right now and will refer anyone to the archives which may be searched at the following URL: http://lsv.ceramics.org/scripts/wa.exe?S1=clayart
Date: Wed, 9 Apr 1997 08:58:16 EDT
Reply-To: kplatt@glass.com
Sender: Ceramic Arts Discussion List
From: "Karl P. Platt"
Organization: Universidade Federal de Santa Catarina (UFSC)
Subject: Our Fat Friend -- Barry the Barium ion
Content-Type: text/plain; charset=iso-8859-1
Content-Type: TEXT/PLAIN; charset=US-ASCII
----------------------------Original message----------------------------
Subject: Re: Ba leaching (long and picky) From: Bill Walker
>>I suspect that BaSiO3 is not the only crystalline barium compound
found in glazes, considering the wide range of formulations that people
might try.<<
Others are (thermodynamically speaking) a lot less likely to be seen.
Formulations vary more in style than substance. The palette of elements
present in potter's glazes is, in fact, quite limited. BaSiO3 is, in a
large majority of cases, far more likely than any other combination one
might find.
>>agitating would increase the release rate<<
Significantly.
>>Food is frequently stored or cooked in ceramic containers.<<
Cooking is of far greater concern that storage. The (already slow)
reaction rates are retarded by low temperatures and elevated at high
temperatures. This is particularly true for the case of Ba as has been
noted in an earlier posting.
>>Potters often use barium because of its influence on color and
texture <<
So? -- >when used in large amounts it produces beautiful effects that
would >not be considered appropriate for chemical vats or the food
processing >industry where a smooth, usually white surface is desirable.
The glazes in question which I made were colored using a Cr-Fe-Zn stain
-- if I recall it was Pemco's GS-514 (which makes a very cool orange in
high ZnO glazes). Mason's Saturn Orange is of the same class of pigments.
>Out of the Millions of items of trouble >free tableware made by US
producers, the only documented cases of >leaching problems (poisoning)
have been with foreign products.
>>Because the importers did not have the stuff tested! >>And probably
did not know that they should!
Of course they didn't and it's not that they didn't know -- they didn't
care. And the US makers get penalized with the burden of yet more
regulatory overhead that increases consumer costs without providing any
measurable benefit -- remember there wasn't and hadn't been a problem
with the US made goods.
>>But you still have to test!
For what and why? There is _no_ Ba leaching standard because there is no
Ba leaching "problem". It doesn't exist. Nco Existe!
No one in the history of humanity has become ill from Ba leached off of
a dinnerplate or coffee cup. The odds of having anyone taken ill by a
plate with Ba bearing glaze on it are about the same as winning the NY
State Lootery -- er, lottery.
>>Are you suggesting 0.02 ppm as the safe level?
I made no such suggestion. This is, however, no less arbitrary as any
other standard that has been suggested. Note that 0.02 ppm is equivalent
to .02 grams in a metric ton. This would exist in most places as a
consequence of nature. But then didn't I hear the EPA was looking for a
way condemn God for putting it there in the first place -- this is their
secret plan for dealing with the Federal Debt. They're going to sue God
for all he's got and we'll all get rich.
>>The extreme cases being those glazes that release 3000ppm that no one
>>ever tested because someone doubted, was ignorant of or chose to
>>ingnore the
Please, please, please forward to me by FAX 55.48.234.0059 any and all
details as to this incident including the name and address of the person
who was taken ill, their physician, and the potter so that I can verify
these utterly historic precedents for our collective posterity. I am
also extremely interested to see the formula and firing conditions used
to make this glaze.
>>Or are we only considering glazes that are in thermodynamic
equilibrium?<<
Nothing is in equilibrium --- for long -- Entropy happens.
Karl P. Platt -- still extremely worried about the pernicious presence
of Dihydrogen monoxide and hovering over the Fax machine.
Edouard Bastarache on sun 11 nov 01
Hello Karl,
Right on.
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://www.absolutearts.com/portfolios/e/edouardb/
----- Original Message -----
From: Karl P. Platt
To:
Sent: Saturday, November 10, 2001 12:26 PM
Subject: Barium Repost from 4 years ago
> This is one repost concerning the use of BaO in ceramic glazes. I'm
disheartened to see that discussion on this topic remains so poorly resolved
> and would suggest that half-truths and nonsense prevail over any
meaningful discussion of the topic.
>
> A single fact (of many) needs to be reiterated. There is no history
anywhere of anyone ever being physically compromised for having consumed
food or drink from a BaO bearing Glaze.
> I repeat never, ever, anywhere.
>
> I don't have time to discuss the use of barium in any serious way right
now and will refer anyone to the archives which may be searched at the
following URL: http://lsv.ceramics.org/scripts/wa.exe?S1=clayart
>
>
>
>
>
>
>
> Date: Wed, 9 Apr 1997 08:58:16 EDT
> Reply-To: kplatt@glass.com
> Sender: Ceramic Arts Discussion List
> From: "Karl P. Platt"
> Organization: Universidade Federal de Santa Catarina (UFSC)
> Subject: Our Fat Friend -- Barry the Barium ion
> Content-Type: text/plain; charset=iso-8859-1
> Content-Type: TEXT/PLAIN; charset=US-ASCII
>
> ----------------------------Original message----------------------------
> Subject: Re: Ba leaching (long and picky) From: Bill Walker
>
>
> >>I suspect that BaSiO3 is not the only crystalline barium compound
> found in glazes, considering the wide range of formulations that people
> might try.<<
>
> Others are (thermodynamically speaking) a lot less likely to be seen.
> Formulations vary more in style than substance. The palette of elements
> present in potter's glazes is, in fact, quite limited. BaSiO3 is, in a
> large majority of cases, far more likely than any other combination one
> might find.
>
> >>agitating would increase the release rate<<
>
> Significantly.
>
> >>Food is frequently stored or cooked in ceramic containers.<<
>
> Cooking is of far greater concern that storage. The (already slow)
> reaction rates are retarded by low temperatures and elevated at high
> temperatures. This is particularly true for the case of Ba as has been
> noted in an earlier posting.
>
> >>Potters often use barium because of its influence on color and
> texture <<
>
> So? -- >when used in large amounts it produces beautiful effects that
> would >not be considered appropriate for chemical vats or the food
> processing >industry where a smooth, usually white surface is desirable.
>
> The glazes in question which I made were colored using a Cr-Fe-Zn stain
> -- if I recall it was Pemco's GS-514 (which makes a very cool orange in
> high ZnO glazes). Mason's Saturn Orange is of the same class of pigments.
>
> >Out of the Millions of items of trouble >free tableware made by US
> producers, the only documented cases of >leaching problems (poisoning)
> have been with foreign products.
>
> >>Because the importers did not have the stuff tested! >>And probably
> did not know that they should!
>
> Of course they didn't and it's not that they didn't know -- they didn't
> care. And the US makers get penalized with the burden of yet more
> regulatory overhead that increases consumer costs without providing any
> measurable benefit -- remember there wasn't and hadn't been a problem
> with the US made goods.
>
> >>But you still have to test!
>
> For what and why? There is _no_ Ba leaching standard because there is no
> Ba leaching "problem". It doesn't exist. Nco Existe!
>
> No one in the history of humanity has become ill from Ba leached off of
> a dinnerplate or coffee cup. The odds of having anyone taken ill by a
> plate with Ba bearing glaze on it are about the same as winning the NY
> State Lootery -- er, lottery.
>
> >>Are you suggesting 0.02 ppm as the safe level?
>
> I made no such suggestion. This is, however, no less arbitrary as any
> other standard that has been suggested. Note that 0.02 ppm is equivalent
> to .02 grams in a metric ton. This would exist in most places as a
> consequence of nature. But then didn't I hear the EPA was looking for a
> way condemn God for putting it there in the first place -- this is their
> secret plan for dealing with the Federal Debt. They're going to sue God
> for all he's got and we'll all get rich.
>
> >>The extreme cases being those glazes that release 3000ppm that no one
> >>ever tested because someone doubted, was ignorant of or chose to
> >>ingnore the
>
> Please, please, please forward to me by FAX 55.48.234.0059 any and all
> details as to this incident including the name and address of the person
> who was taken ill, their physician, and the potter so that I can verify
> these utterly historic precedents for our collective posterity. I am
> also extremely interested to see the formula and firing conditions used
> to make this glaze.
>
> >>Or are we only considering glazes that are in thermodynamic
> equilibrium?<<
>
> Nothing is in equilibrium --- for long -- Entropy happens.
>
> Karl P. Platt -- still extremely worried about the pernicious presence
> of Dihydrogen monoxide and hovering over the Fax machine.
>
>
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Ron Roy on sun 11 nov 01
Just tell us where we can see the results of studies on leached barium on
living organizms - if there are any.
If there are no such studies - of course you would not have heard the results.
RR
>This is one repost concerning the use of BaO in ceramic glazes. I'm
>disheartened to see that discussion on this topic remains so poorly
>resolved
>and would suggest that half-truths and nonsense prevail over any
>meaningful discussion of the topic.
>
>A single fact (of many) needs to be reiterated. There is no history
>anywhere of anyone ever being physically compromised for having consumed
>food or drink from a BaO bearing Glaze.
>I repeat never, ever, anywhere.
>
>I don't have time to discuss the use of barium in any serious way right
>now and will refer anyone to the archives which may be searched at the
>following URL: http://lsv.ceramics.org/scripts/wa.exe?S1=clayart
Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513
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