Lily Krakowski on mon 19 may 03
And here I thought Galena was Salvator Dali's wife!
Survival is not the issue with lead. It is cumulativew poison and like
other heavy metals sort of nibbles at the body. One gets aches and pains,
one's nails turn blue, one's teeth loosen, one's brain cells take early
retirement. In a world where people died at 40 or so, and no one was
expected to be in good shape into old age, this sort of thing was "accepted"
I think it was EP Thompson who wrote that people started work as children
and were through by 40--exactly because of poisonings, breathing cotton
dust, coal dust and so on. Do read Mrs Gaskell's "North and South" as well
as some books on the Luddites to get an insight on the health damages caused
by the Industrial Revolution.
However. The older books do mention Galena, and I think Leach does too.
Bun Bun writes:
> I am very aware what Galena is. I live in the Lead Belt of Missouri. If I
> wanted information on the dangers of lead I would have asked "that"
> question. I can't help but wonder just HOW the human race got by using
> lead
> in glaze for 5000 years without distroying itself. No intelligent person
> would use it on food containers because of the modern day warnings. This
> is
> not SARS, it won't jump up and kill you in a moments contact. People have
> been injesting lead in this area for generations, and yes some of the
> residents are surely brain dead but cancer is the formost killer here.
> Safety precausions must be taken even when cooking dinner. God forbid
> anybody does anything considered dangerous by the FDA.
>
> I would recommend not walking across a street, see a doctor if you need a
> band aide, don't drink milk if its out of date, don't use wood for
> heating,
> etc, etc.
>
> _________________________________________________________________
> Add photos to your e-mail with MSN 8. Get 2 months FREE*.
> http://join.msn.com/?page=features/featuredemail
>
> __________________________________________________________________________
> ____
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
Lili Krakowski
P.O. Box #1
Constableville, N.Y.
(315) 942-5916/ 397-2389
Be of good courage....
Bun Bun on mon 19 may 03
I am very aware what Galena is. I live in the Lead Belt of Missouri. If I
wanted information on the dangers of lead I would have asked "that"
question. I can't help but wonder just HOW the human race got by using lead
in glaze for 5000 years without distroying itself. No intelligent person
would use it on food containers because of the modern day warnings. This is
not SARS, it won't jump up and kill you in a moments contact. People have
been injesting lead in this area for generations, and yes some of the
residents are surely brain dead but cancer is the formost killer here.
Safety precausions must be taken even when cooking dinner. God forbid
anybody does anything considered dangerous by the FDA.
I would recommend not walking across a street, see a doctor if you need a
band aide, don't drink milk if its out of date, don't use wood for heating,
etc, etc.
_________________________________________________________________
Add photos to your e-mail with MSN 8. Get 2 months FREE*.
http://join.msn.com/?page=features/featuredemail
Earl Brunner on mon 19 may 03
Lead may have not caused the human race to go extinct
in 5000 years, but it has caused LOTS of problems,
lead use has been associated with the fall of the
Roman Empire.....
If you want information, go to some of the OLD books,
say pre 1970. Look into the legal issues, since you
are sooooo smart.
--- Bun Bun wrote:
> I am very aware what Galena is. I live in the Lead
> Belt of Missouri. If I
> wanted information on the dangers of lead I would
> have asked "that"
> question. I can't help but wonder just HOW the
> human race got by using lead
> in glaze for 5000 years without distroying itself.
> No intelligent person
> would use it on food containers because of the
> modern day warnings. This is
> not SARS, it won't jump up and kill you in a moments
> contact. People have
> been injesting lead in this area for generations,
> and yes some of the
> residents are surely brain dead but cancer is the
> formost killer here.
> Safety precausions must be taken even when cooking
> dinner. God forbid
> anybody does anything considered dangerous by the
> FDA.
>
> I would recommend not walking across a street, see a
> doctor if you need a
> band aide, don't drink milk if its out of date,
> don't use wood for heating,
> etc, etc.
>
>
_________________________________________________________________
> Add photos to your e-mail with MSN 8. Get 2 months
> FREE*.
> http://join.msn.com/?page=features/featuredemail
>
>
______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change
> your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be
> reached at melpots@pclink.com.
=====
Earl Brunner
e-mail: brunv53@yahoo.com
claybair on mon 19 may 03
Dear Bun Bun,
Don't get your knickers in a twist :-)
Without stating that you were aware of the dangers
no one could respond responsibly without
a proper warning.
All levels of potters write to and read this forum.
One thing I didn't know that I learned for this forum
is that you can contaminate your kiln by using lead glazes.
If you are planning to fire functional work in the same kiln
you might want to look up the info. in archives.
Gayle Bair
Bainbridge Island, WA
http://claybair.com
-----Original Message-----
From: Clayart Bun Bun
I am very aware what Galena is. I live in the Lead Belt of Missouri. If I
wanted information on the dangers of lead I would have asked "that"
question. I can't help but wonder just HOW the human race got by using lead
in glaze for 5000 years without distroying itself. No intelligent person
would use it on food containers because of the modern day warnings. This is
not SARS, it won't jump up and kill you in a moments contact. People have
been injesting lead in this area for generations, and yes some of the
residents are surely brain dead but cancer is the formost killer here.
Safety precausions must be taken even when cooking dinner. God forbid
anybody does anything considered dangerous by the FDA.
I would recommend not walking across a street, see a doctor if you need a
band aide, don't drink milk if its out of date, don't use wood for heating,
etc, etc.
_________________________________________________________________
Add photos to your e-mail with MSN 8. Get 2 months FREE*.
http://join.msn.com/?page=features/featuredemail
____________________________________________________________________________
__
Send postings to clayart@lsv.ceramics.org
You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/
Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
Suzanne Wolfe on tue 20 may 03
On Mon, 19 May 2003, Lily Krakowski wrote:
> And here I thought Galena was Salvator Dali's wife!
Lily -- She was Gala -- and Dali did a cookbook especially dedicated to
her. Never tried the recipes.
Suzanne
Janet Kaiser on tue 20 may 03
WHAT an ATTITUDE?!? Apart from being one of the silliest posts in a long
time, everyone was supposed to understand by some sort of symbiosis that
you know "all about" lead? That the FDA are out to get you, not protect you
and that you don't care for THEM telling US what to do or not do. It is a
remarkably cavalier attitude to such a very serious issue. You prefer lead
poisoning to cancer, if you are not already brain dead? Fine. All advice
will obviously, be unwanted and considered "unnecessary". Point taken.
But FYI it is not the ingestion from the glaze on finished functional ware
which is dangerous to the MAKER, it is working with raw lead day-in,
day-out. Breathing, touching, ingesting and skin contact through the whole
glaze mixing, application and firing process. In an environment which is
already laden with lead, just adding a little more won't hurt YOU, right?
And who are WE to worry about YOUR health? Don't worry, your sarcasm will
cure many of that unforgivable sin against your personal freedom to do what
the hell you want.
And if you are so hell bent on using Galena anyway, I suggest you get hold
of some pre 1940 books on ceramics... Even 1950s and 1960s still published
a wide range of recipes for White Lead which I am sure in your infinite
wisdom you will be able to adapt easily. Good luck to you!
Sincerely
Janet Kaiser
*** IN REPLY TO THE FOLLOWING MAIL:
>I am very aware what Galena is. I live in the Lead Belt of Missouri. If I
>wanted information on the dangers of lead I would have asked "that"
>question. I can't help but wonder just HOW the human race got by using
lead
>in glaze for 5000 years without distroying itself. No intelligent person
>would use it on food containers because of the modern day warnings. This
>is
>not SARS, it won't jump up and kill you in a moments contact. People have
>been injesting lead in this area for generations, and yes some of the
>residents are surely brain dead but cancer is the formost killer here.
>Safety precausions must be taken even when cooking dinner. God forbid
>anybody does anything considered dangerous by the FDA.
>
>I would recommend not walking across a street, see a doctor if you need a
>band aide, don't drink milk if its out of date, don't use wood for
heating,
>etc, etc.
*** THE MAIL FROM Bun Bun ENDS HERE ***
**********************************************************************
TRUTH is too precious to tell every fool who asks for it...
****** This post was sent to you today by Janet Kaiser *******
The Chapel of Art / Capel Celfyddyd
8 Marine Crescent, Criccieth LL52 0EA, Wales, UK
Tel: ++44 (01766) 523570 URL: http://www.the-coa.org.uk
**********************************************************************
Ron Roy on sun 17 oct 04
Jon said
"----the quite stiff unleaded glazes
>commonly crammed down our throats by people who don t think potters are
>capable of using lead safely. I hope that doesn t sound too opinionated."
What a strange thing to say - who crammed what down whos throat?
It only takes a few to ruin it for everyone - and even some table ware
manufactures were apparently incapable of making lead glazes that didn't
leach lead into food.
I would be interested in knowing if you know any potters who are capable of
making a lead glaze that will not leach lead into food - can you?
I certainly would have to do a lot of experimenting and testing and even
then - if I published the glaze - would it be fired properly.
There are good reasons to make sure potters who use lead on functional ware
are checked up on.
Then there is the danger to the potter from dust and firing.
RR
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Jon Pacini on mon 18 oct 04
Greetings All----Hi Ron---- You seem to always want to put these discussions
in the context of functional tableware. Not all people who work in ceramics
work in functional tableware. And to my knowledge there are a great many
items made of clay and glaze that never come into contact with food. Yet the
big lead bug-a-boo looms over the entire ceramics field. It is an
emotionally charged, knee-jerk topic.
I would hold that it is much better to understand the minerals we have
available to us, their benefits as well as hazards, rather than put a
blanket prohibition on them. Which is effectively what has been done with
lead. Yes it's toxic, yes it can be mishandled, but I don't believe in
prohibiting the use of a mineral for those reasons. I believe if you are
knowledgeable a person can successfully use this type of mineral with out
putting themselves or their customers in harms way.
Because of the toxicity issues surrounding lead and the misuse potential
that you have pointed out, you won't find much, if any of it, in
commercially produced glazes. It can no doubt be justified in not allowing
this type of glaze to contain lead because of it's potential for misuse. So
potters who use commercially prepared glazes are in effect stuck with what
is supplied to them. And that is particularly the case in the Low fire range
where lead was once prevalent. That is what I meant by 'crammed down our
throats'.
The fact that you are concerned that someone may misuse a glaze you have
developed and published is a good thing. And that you feel so strongly about
not using Lead in tableware is very prudent. Making the world safe from
possible hazards is a wonderful Ideal to live by. But I think we're much
better off teaching about the proper use of the materials than slapping
peoples hands and saying "no-no, you can't touch that".
Yes, potters can develop their own lead glazes, but the publics' phobia of
lead poisoning whether there is actually any lead release or not from the
ware, precludes many from trying. Also a potter who wants to develop lead
glazes for uses other than for tableware has great obstacles in education to
over come. When I was in school there was still lead in the classroom and
teachers that knew how to use it. They were not ignorant of the hazards, but
neither were they hysterical about it. Today you will not find lead in many
classrooms because of the prohibition on it and you won't find many ceramic
teachers who know much about lead's proper use and handling. I would think
that without that knowledge, the potential for misuse is actually greater.
We can argue this forever -----The bottom line is you can't take minerals
away from the potters' palette because they have the potential for misuse.
Ceramics is full of toxic and/or hazardous minerals. You can't prohibit the
use of them all. Well you could, but you'd end up with next to nothing to
use for clay or glaze. The State of California has legislated that Silica is
a cancer causing mineral and that all materials manufactured in California
that contain free silica must carry a cancer warning label. If at some point
the Legislature decides that silica is potentially too hazardous a material
to allow the public to handle, then what do potters do???
Sure, it sounds silly, but that's the road you go down. Where do you draw
the line on minerals that are potentially hazardous?
Do you stop with Lead? How about Barium, Manganese, Copper or Silica. And
the list doesn't end there.
So---- I'll remain convinced that we're better off educating potters on the
hazards and the benefits of the minerals that we have available to us rather
than prohibit any of them from use.
Best regards
Jon Pacini
Clay Manager
Laguna Clay Co.
-----Original Message-----
From: Ron Roy [mailto:ronroy@ca.inter.net]
Sent: Sunday, October 17, 2004 11:27 AM
To: Clayart
Cc: Jon Pacini
Subject: Re: lead glazes
Jon said
"----the quite stiff unleaded glazes
>commonly crammed down our throats by people who don t think potters are
>capable of using lead safely. I hope that doesn t sound too opinionated."
What a strange thing to say - who crammed what down whos throat?
It only takes a few to ruin it for everyone - and even some table ware
manufactures were apparently incapable of making lead glazes that didn't
leach lead into food.
I would be interested in knowing if you know any potters who are capable of
making a lead glaze that will not leach lead into food - can you?
I certainly would have to do a lot of experimenting and testing and even
then - if I published the glaze - would it be fired properly.
There are good reasons to make sure potters who use lead on functional ware
are checked up on.
Then there is the danger to the potter from dust and firing.
RR
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Edouard Bastarache Inc. on mon 18 oct 04
"When I was in school there was still lead in the classroom and
teachers that knew how to use it. They were not ignorant of the
hazards, but neither were they hysterical about it."
Jon Pacini
Hello all,
Leaded wares spend most of their time in the cupbord and the dishwasher,
and we do a 24-hour vinegar extraction test.
In the Old Europe (G'day Mr. Rumsfeld) lead is not used in wares intended
for communities such as restaurants customers, hospital patients, etc.
But, I still believe lead can be used safely if proper formulation,
information
are available, and if lead leaching testing is conducted regularly.
If I recall correctly 4 metals must be tested over there :
-cadmium,
-lead,
-arsenic,
-chromium.
but, these tests applied to all types of containers intended to store food,
not only ceramic wares, whatever the materials used and whatever the
lenght of time foodstuffs will remain in the containers.
In Quebec only quartz, not cristobalite trydimite or tripoli , is
considered a "suspected carcinogen".
Later,
"Ils sont fous ces quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.digitalfire.com/education/toxicity/
Louis Katz on tue 19 oct 04
Hi Edouard,
I want to make sure i am clear about something. Do you think that
leached chromium from glazes is a cause for concern?I looked for your
article and found:
http://www.digitalfire.ab.ca/cermat/education/182.html
Thank you.
I assume that the chromium leached from a glaze would be trivalent or
become so in the gastro intestinal tract prior to absoption. Is this a
reasonably good assumption? I read the toxic does and noticed that it
was relatively high but wonder how much chrome might be considered a
problem when leached from a glaze.
Thank you for your time I have printed out your materials on the
digital fire sight and keep them near the MSDS sheets. They are much
more useful and provide a valuable service.
Louis
>
> If I recall correctly 4 metals must be tested over there :
> -cadmium,
> -lead,
> -arsenic,
> -chromium.
Louis Katz
WIKI site http://www.tamucc.edu/wiki/Katz/HomePage
Edouard Bastarache Inc. on tue 19 oct 04
Hello Louis,
a few statements before I answer your questions:
1-Chromium is an essential trace element and is present in tissues in =
its trivalent state.
2-In the industry, workers may be exposed to trivalent and hexavalent =
chromium compounds
whose metabolic handling and toxicity are strikingly different.
3-Trivalent chromium is absorbed poorly by inhalation and throught =
intact skin,=20
resulting in a low order of systemic toxicity. However, should trivalent =
chromium gain=20
access to the systemic circulation, toxic effects may develop.
4-Trivalent chromium salts are absorbed after ingestion, but only 1% to =
25% of the=20
dose ingested is absorbed.=20
5-Trivalent salts are poorly absorbed through intact skin but, once the =
dermal barrier=20
is broken, however, absorption may occur.
6-Trivalent chromium only penetrates with much difficulty into the skin =
and the risk=20
of sensitizing is thus weak. Chromium metal is not in theory an allergen =
7-The risk of lung cancer appears non-existent among tanners using =
mainly trivalent=20
chromium compounds.
8-Trivalent chromium per se is not genotoxic as demonstrated in =
epidemiologic
studies among which one conducted among exposed tannery workers.
Your questions now :
"I want to make sure i am clear about something. Do you think that
leached chromium from glazes is a cause for concern?I looked for your
article and found:
http://www.digitalfire.ab.ca/cermat/education/182.html
Thank you.
Louis"
My answer is no considering the low order of toxicity of green chromium =
oxide
generally used to color glazes.
Secondly the amounts used are very low if you compare them to the =
amounts of
lead compounds used in leaded glazes (EB)
-------------------------------------------------------------------------=
-----------------------------
"I assume that the chromium leached from a glaze would be trivalent or
become so in the gastro intestinal tract prior to absoption. Is this a
reasonably good assumption? I read the toxic does and noticed that it
was relatively high but wonder how much chrome might be considered a
problem when leached from a glaze.
Louis"
Indeed, green chromium oxide is trivalent, I can not tell you how much=20
may leach from a glaze, too many different glaze recipes are available.
Chromium in glaze leaching is not regulated in North America for the=20
above reasons, I do not know of any standard; but I would not worry
about its presence in my "french pea soup"(EB)=20
-------------------------------------------------------------------------=
----------------------------
=20
" Thank you for your time I have printed out your materials on the
digital fire sight and keep them near the MSDS sheets. They are much
more useful and provide a valuable service.
Louis"
=20
Welcome(EB)
-------------------------------------------------------------------------=
----------------------------=20
There are other componds than green chromium oxide that can be used in=20
ceramics:
-iron chromite (trivalent, confirmed carcinogen during ore processing =
only,
exposure limit=3D0.05 mg/m=B3),=20
-potassium dichromate (soluble hexavalent, exposure limit=3D0.05 =
mg/m=B3,
confirmed human carcinogen)=20
-stains (?).=20
Later,
"Ils sont fous ces quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.digitalfire.com/education/toxicity/
Louis Katz on tue 19 oct 04
Edouard,
Thank you very much, we are lucky to have you on this forum.
Louis
On Oct 19, 2004, at 2:32 PM, Edouard Bastarache Inc. wrote:
> Hello Louis,
>
>
>
> a few statements before I answer your questions:
>
>
>
>
>
> 1-Chromium is an essential trace element and is present in tissues in =20=
> its trivalent state.
>
> 2-In the industry, workers may be exposed to trivalent and hexavalent =20=
> chromium compounds
>
> whose metabolic handling and toxicity are strikingly different.
>
> 3-Trivalent chromium is absorbed poorly by inhalation and throught =20
> intact skin,
>
> resulting in a low order of systemic toxicity. However, should =20
> trivalent chromium gain
>
> access to the systemic circulation, toxic effects may develop.
>
> 4-Trivalent chromium salts are absorbed after ingestion, but only 1% =20=
> to 25% of the
>
> dose ingested is absorbed.
>
> 5-Trivalent salts are poorly absorbed through intact skin but, once =20=
> the dermal barrier
>
> is broken, however, absorption may occur.
>
> 6-Trivalent chromium only penetrates with much difficulty into the =20=
> skin and the risk
>
> of sensitizing is thus weak. Chromium metal is not in theory an =20
> allergen
>
> 7-The risk of lung cancer appears non-existent among tanners using =20
> mainly trivalent
>
> chromium compounds.
>
> 8-Trivalent chromium per se is not genotoxic as demonstrated in =20
> epidemiologic
>
> studies among which one conducted among exposed tannery workers.
>
>
>
> Your questions now :
>
>
> "I want to make sure i am clear about something. Do you think that
> leached chromium from glazes is a cause for concern?I looked for your
> article and found:
> http://www.digitalfire.ab.ca/cermat/education/182.html
> Thank you.
> Louis"
>
> My answer is no considering the low order of toxicity of green =20
> chromium oxide
> generally used to color glazes.
> Secondly the amounts used are very low if you compare them to the =20
> amounts of
> lead compounds used in leaded glazes (EB)
>
> =
-----------------------------------------------------------------------=20=
> -------------------------------
>
> "I assume that the chromium leached from a glaze would be trivalent or
> become so in the gastro intestinal tract prior to absoption. Is this =
a
> reasonably good assumption? I read the toxic does and noticed that it
> was relatively high but wonder how much chrome might be considered a
> problem when leached from a glaze.
> Louis"
>
> Indeed, green chromium oxide is trivalent, I can not tell you how much
> may leach from a glaze, too many different glaze recipes are =
available.
> Chromium in glaze leaching is not regulated in North America for the
> above reasons, I do not know of any standard; but I would not worry
> about its presence in my "french pea soup"(EB)
>
> =
-----------------------------------------------------------------------=20=
> ------------------------------
>
> " Thank you for your time I have printed out your materials on the
> digital fire sight and keep them near the MSDS sheets. They are much
> more useful and provide a valuable service.
> Louis"
>
> Welcome(EB)
>
> =
-----------------------------------------------------------------------=20=
> ------------------------------
> There are other componds than green chromium oxide that can be used in
> ceramics:
> -iron chromite (trivalent, confirmed carcinogen during ore processing =20=
> only,
> exposure limit=3D0.05 mg/m=B3),
> -potassium dichromate (soluble hexavalent, exposure limit=3D0.05 =
mg/m=B3,
> confirmed human carcinogen)
> -stains (?).
>
>
>
> Later,
>
>
> "Ils sont fous ces quebecois"
> Edouard Bastarache
> Irreductible Quebecois
> Indomitable Quebeker
> Sorel-Tracy
> Quebec
> edouardb@sorel-tracy.qc.ca
> www.sorel-tracy.qc.ca/~edouardb/Welcome.html
> http://perso.wanadoo.fr/smart2000/index.htm
> http://www.digitalfire.com/education/toxicity/
>
> =
_______________________________________________________________________=20=
> _______
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at =20
> melpots@pclink.com.
>
Ron Roy on wed 20 oct 04
Hi Jon,
Your original statement did not mention any qualification - like for non
functional use - so why bring it up now? Seems as if you deliberately
wanted to talk about this - I'm just accommodating you.
I agree about informing potters about the proper use of materials - but in
the meantime - what do you suggest we do? So far only our book addresses
the issue.
So we agree again - education is needed - what are you doing about it?
In the meantime - I see examples of potters and teachers working in
hazardous conditions and they don't even realize it - and producing ware
that - in some cases - is dangerous. The net effect is a damaged market
place and all potters suffer the consequences.
It is easy to complain about restrictions - perhaps that gives us the
excuse to do nothing about the problems. There is plenty of denial in our
business and the net result is the attitude of - lets not talk about the
problems - nobody will get upset - and life will be easy. Well thats why it
happened with lead - uninformed people playing with toxic materials - a
sure way to end up with more restrictions.
RR
>Greetings All----Hi Ron---- You seem to always want to put these discussions
>in the context of functional tableware. Not all people who work in ceramics
>work in functional tableware. And to my knowledge there are a great many
>items made of clay and glaze that never come into contact with food. Yet the
>big lead bug-a-boo looms over the entire ceramics field. It is an
>emotionally charged, knee-jerk topic.
>
>I would hold that it is much better to understand the minerals we have
>available to us, their benefits as well as hazards, rather than put a
>blanket prohibition on them. Which is effectively what has been done with
>lead. Yes it's toxic, yes it can be mishandled, but I don't believe in
>prohibiting the use of a mineral for those reasons. I believe if you are
>knowledgeable a person can successfully use this type of mineral with out
>putting themselves or their customers in harms way.
>
>Because of the toxicity issues surrounding lead and the misuse potential
>that you have pointed out, you won't find much, if any of it, in
>commercially produced glazes. It can no doubt be justified in not allowing
>this type of glaze to contain lead because of it's potential for misuse. So
>potters who use commercially prepared glazes are in effect stuck with what
>is supplied to them. And that is particularly the case in the Low fire range
>where lead was once prevalent. That is what I meant by 'crammed down our
>throats'.
>
>The fact that you are concerned that someone may misuse a glaze you have
>developed and published is a good thing. And that you feel so strongly about
>not using Lead in tableware is very prudent. Making the world safe from
>possible hazards is a wonderful Ideal to live by. But I think we're much
>better off teaching about the proper use of the materials than slapping
>peoples hands and saying "no-no, you can't touch that".
>
>Yes, potters can develop their own lead glazes, but the publics' phobia of
>lead poisoning whether there is actually any lead release or not from the
>ware, precludes many from trying. Also a potter who wants to develop lead
>glazes for uses other than for tableware has great obstacles in education to
>over come. When I was in school there was still lead in the classroom and
>teachers that knew how to use it. They were not ignorant of the hazards, but
>neither were they hysterical about it. Today you will not find lead in many
>classrooms because of the prohibition on it and you won't find many ceramic
>teachers who know much about lead's proper use and handling. I would think
>that without that knowledge, the potential for misuse is actually greater.
>
>We can argue this forever -----The bottom line is you can't take minerals
>away from the potters' palette because they have the potential for misuse.
>Ceramics is full of toxic and/or hazardous minerals. You can't prohibit the
>use of them all. Well you could, but you'd end up with next to nothing to
>use for clay or glaze. The State of California has legislated that Silica is
>a cancer causing mineral and that all materials manufactured in California
>that contain free silica must carry a cancer warning label. If at some point
>the Legislature decides that silica is potentially too hazardous a material
>to allow the public to handle, then what do potters do???
>
>Sure, it sounds silly, but that's the road you go down. Where do you draw
>the line on minerals that are potentially hazardous?
>Do you stop with Lead? How about Barium, Manganese, Copper or Silica. And
>the list doesn't end there.
>
>So---- I'll remain convinced that we're better off educating potters on the
>hazards and the benefits of the minerals that we have available to us rather
>than prohibit any of them from use.
>
>Best regards
>Jon Pacini
>Clay Manager
>Laguna Clay Co.
>
>
>
>-----Original Message-----
>From: Ron Roy [mailto:ronroy@ca.inter.net]
>Sent: Sunday, October 17, 2004 11:27 AM
>To: Clayart
>Cc: Jon Pacini
>Subject: Re: lead glazes
>
>Jon said
>
>"----the quite stiff unleaded glazes
>>commonly crammed down our throats by people who don t think potters are
>>capable of using lead safely. I hope that doesn t sound too opinionated."
>
>What a strange thing to say - who crammed what down whos throat?
>
>It only takes a few to ruin it for everyone - and even some table ware
>manufactures were apparently incapable of making lead glazes that didn't
>leach lead into food.
>
>I would be interested in knowing if you know any potters who are capable of
>making a lead glaze that will not leach lead into food - can you?
>
>I certainly would have to do a lot of experimenting and testing and even
>then - if I published the glaze - would it be fired properly.
>
>There are good reasons to make sure potters who use lead on functional ware
>are checked up on.
>
>Then there is the danger to the potter from dust and firing.
>
>RR
>
>Ron Roy
>RR#4
>15084 Little Lake Road
>Brighton, Ontario
>Canada
>K0K 1H0
>Phone: 613-475-9544
>Fax: 613-475-3513
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Jon Pacini on thu 21 oct 04
Greetings All-----Hi Ron --- I truly appreciate your accommodation Ron, and
we really have to stop agreeing so much--- people may get the impression we
are one and the same person posting under different e-mail addresses.
My intentions for the present are to continue talking/writing in this forum
and elsewhere about how we as crafts men and women shouldn't be afraid of
our materials. About how respect should be given to hazardous materials, but
being afraid of them is of no value. And encouraging potters to try things
that others say can't be done.
As exhibited---this is a good forum for that dialog.
If I can fill up enough posts on these and other subjects then maybe I too
will have enough material for a book. Though I doubt I could do one as
technically proficient as yours.
I hate to beg off our dialog, but I've got a lot to get accomplished here at
the plant and I'm leaving shortly for Phoenix Ariz. I'll be attending the
Potters Olympics being held Saturday at Marjon Ceramic Supply. It will be a
dual role for me, as a participant and a representative of a sponsor. The
Blindfolded Throwing is my favorite event with Throwing With Your Feet a
close second.
-------- I trust everyone will hang on to their seats till we continue at a
later date : )
Best regards
Jon Pacini
Clay Manager
Laguna Clay Co.
Where it's been raining for 3 days and everyone has forgotten how to drive.
-----Original Message-----
From: Ron Roy [mailto:ronroy@ca.inter.net]
Sent: Wednesday, October 20, 2004 1:02 PM
To: Clayart
Cc: Jon Pacini
Subject: Re: lead glazes
Hi Jon,
Your original statement did not mention any qualification - like for non
functional use - so why bring it up now?
Seems as if you deliberately
wanted to talk about this - I'm just accommodating you.
I agree about informing potters about the proper use of materials - but in
the meantime - what do you suggest we do? So far only our book addresses
the issue.
So we agree again - education is needed - what are you doing about it?
In the meantime - I see examples of potters and teachers working in
hazardous conditions and they don't even realize it - and producing ware
that - in some cases - is dangerous. The net effect is a damaged market
place and all potters suffer the consequences.
It is easy to complain about restrictions - perhaps that gives us the
excuse to do nothing about the problems. There is plenty of denial in our
business and the net result is the attitude of - lets not talk about the
problems - nobody will get upset - and life will be easy. Well thats why it
happened with lead - uninformed people playing with toxic materials - a
sure way to end up with more restrictions.
RR
>Greetings All----Hi Ron---- You seem to always want to put these
discussions
>in the context of functional tableware. Not all people who work in ceramics
>work in functional tableware. And to my knowledge there are a great many
>items made of clay and glaze that never come into contact with food. Yet
the
>big lead bug-a-boo looms over the entire ceramics field. It is an
>emotionally charged, knee-jerk topic.
>
>I would hold that it is much better to understand the minerals we have
>available to us, their benefits as well as hazards, rather than put a
>blanket prohibition on them. Which is effectively what has been done with
>lead. Yes it's toxic, yes it can be mishandled, but I don't believe in
>prohibiting the use of a mineral for those reasons. I believe if you are
>knowledgeable a person can successfully use this type of mineral with out
>putting themselves or their customers in harms way.
>
>Because of the toxicity issues surrounding lead and the misuse potential
>that you have pointed out, you won't find much, if any of it, in
>commercially produced glazes. It can no doubt be justified in not allowing
>this type of glaze to contain lead because of it's potential for misuse. So
>potters who use commercially prepared glazes are in effect stuck with what
>is supplied to them. And that is particularly the case in the Low fire
range
>where lead was once prevalent. That is what I meant by 'crammed down our
>throats'.
>
>The fact that you are concerned that someone may misuse a glaze you have
>developed and published is a good thing. And that you feel so strongly
about
>not using Lead in tableware is very prudent. Making the world safe from
>possible hazards is a wonderful Ideal to live by. But I think we're much
>better off teaching about the proper use of the materials than slapping
>peoples hands and saying "no-no, you can't touch that".
>
>Yes, potters can develop their own lead glazes, but the publics' phobia of
>lead poisoning whether there is actually any lead release or not from the
>ware, precludes many from trying. Also a potter who wants to develop lead
>glazes for uses other than for tableware has great obstacles in education
to
>over come. When I was in school there was still lead in the classroom and
>teachers that knew how to use it. They were not ignorant of the hazards,
but
>neither were they hysterical about it. Today you will not find lead in many
>classrooms because of the prohibition on it and you won't find many ceramic
>teachers who know much about lead's proper use and handling. I would think
>that without that knowledge, the potential for misuse is actually greater.
>
>We can argue this forever -----The bottom line is you can't take minerals
>away from the potters' palette because they have the potential for misuse.
>Ceramics is full of toxic and/or hazardous minerals. You can't prohibit the
>use of them all. Well you could, but you'd end up with next to nothing to
>use for clay or glaze. The State of California has legislated that Silica
is
>a cancer causing mineral and that all materials manufactured in California
>that contain free silica must carry a cancer warning label. If at some
point
>the Legislature decides that silica is potentially too hazardous a material
>to allow the public to handle, then what do potters do???
>
>Sure, it sounds silly, but that's the road you go down. Where do you draw
>the line on minerals that are potentially hazardous?
>Do you stop with Lead? How about Barium, Manganese, Copper or Silica. And
>the list doesn't end there.
>
>So---- I'll remain convinced that we're better off educating potters on the
>hazards and the benefits of the minerals that we have available to us
rather
>than prohibit any of them from use.
>
>Best regards
>Jon Pacini
>Clay Manager
>Laguna Clay Co.
>
>
>
>-----Original Message-----
>From: Ron Roy [mailto:ronroy@ca.inter.net]
>Sent: Sunday, October 17, 2004 11:27 AM
>To: Clayart
>Cc: Jon Pacini
>Subject: Re: lead glazes
>
>Jon said
>
>"----the quite stiff unleaded glazes
>>commonly crammed down our throats by people who don t think potters are
>>capable of using lead safely. I hope that doesn t sound too opinionated."
>
>What a strange thing to say - who crammed what down whos throat?
>
>It only takes a few to ruin it for everyone - and even some table ware
>manufactures were apparently incapable of making lead glazes that didn't
>leach lead into food.
>
>I would be interested in knowing if you know any potters who are capable of
>making a lead glaze that will not leach lead into food - can you?
>
>I certainly would have to do a lot of experimenting and testing and even
>then - if I published the glaze - would it be fired properly.
>
>There are good reasons to make sure potters who use lead on functional ware
>are checked up on.
>
>Then there is the danger to the potter from dust and firing.
>
>RR
>
>Ron Roy
>RR#4
>15084 Little Lake Road
>Brighton, Ontario
>Canada
>K0K 1H0
>Phone: 613-475-9544
>Fax: 613-475-3513
>
>___________________________________________________________________________
___
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Ron Roy on sat 23 oct 04
Hi Jon,
Thanks for the compliment on our book.
Having a heathy regard for the materials we use is not a bad idea -
especially for those who have not bothered to inform themselves about what
dangers are inherent in their use. Call if fear if you want - or you could
also call it respect or even consideration for others. It all depends on
the position you assume. You could even say - knowing which materials are
problematic reduces the apprehension in a way that allows greater
flexibility.
It's all to easy to inject language that makes it easy for potters to
decide there is nothing to worry about - like "hysterical" and "fear."
We have much to learn about the materials we use - and that understanding
can lead to new ways of using them - understanding does not limit
creativity - nor does it guarantee it. Creativity is in the mind of the
maker - not in the materials they use - or don't use.
RR
>Greetings All-----Hi Ron --- I truly appreciate your accommodation Ron, and
>we really have to stop agreeing so much--- people may get the impression we
>are one and the same person posting under different e-mail addresses.
>My intentions for the present are to continue talking/writing in this forum
>and elsewhere about how we as crafts men and women shouldn't be afraid of
>our materials. About how respect should be given to hazardous materials, but
>being afraid of them is of no value. And encouraging potters to try things
>that others say can't be done.
As exhibited---this is a good forum for that dialog.
If I can fill up enough posts on these and other subjects then maybe I too
will have enough material for a book. Though I doubt I could do one as
technically proficient as yours.
I hate to beg off our dialog, but I've got a lot to get accomplished here at
the plant and I'm leaving shortly for Phoenix Ariz. I'll be attending the
Potters Olympics being held Saturday at Marjon Ceramic Supply. It will be a
dual role for me, as a participant and a representative of a sponsor. The
Blindfolded Throwing is my favorite event with Throwing With Your Feet a
close second.
Best regards
Jon Pacini
Clay Manager
Laguna Clay Co.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Overall's on sun 21 jan 07
A friend of mine who shops regularly at the dollar
stores has been buying pots made in China, and
elsewhere, with labels that state something about
Proposition 65 and may or may not contain lead in the
glazes.
If these type wares are prolific now in the states,
how can consumers test to see if there is lead in the
glaze? The same way we test for copper, barium, etc.?
I'll pass it on to her; but I kinda would like to know
myself.
Kim Overall
http://www.kimoverall.com
Bill Merrill on tue 17 may 11
Lead can still be used safely in a glaze if you use Mellors ration
between lead and silica. Lead of course still is potentially dangerous
by handling it raw, breathing the lead dust, etc. Lead also volatizes
in a kiln and will coat the interior of a kiln eventually like a soda or
salt
kiln.
=3D20
The early English potters used lead. I wonder how many of those
potters had health problems from the lead since they probably didn't
know the hazards of lead.
=3D20
Lead is used in what Carlton Ball called "Tizzie glazes. The firing
range of a particular could range from low fire to cone 10. If you are
interested in seeing the Tizzie glaze formulas they are in the Carlton
Ball book "Making Pottery without a wheel". There are also lots of Cone
10 and cone 5 glazes in his book. The cone 10 glazes are very good.
=3D20
I am not trying to convince anyone of using lead, just pointing out how
white lead was used by a contemporary potter at one time during his long
illustrious career.
=3D20
=3D20
Suchman ceramics on wed 18 may 11
How about Yellow lead?..... Litharge?
On Tue, May 17, 2011 at 10:18 AM, Bill Merrill wrote:
> Lead can still be used safely in a glaze if you use Mellors ration
> between lead and silica. Lead of course still is potentially dangerous
> by handling it raw, breathing the lead dust, etc. Lead also volatizes
> in a kiln and will coat the interior of a kiln eventually like a soda or
> salt
>
> kiln.
>
>
>
> The early English potters used lead. I wonder how many of those
> potters had health problems from the lead since they probably didn't
> know the hazards of lead.
>
>
>
> Lead is used in what Carlton Ball called "Tizzie glazes. The firing
> range of a particular could range from low fire to cone 10. If you are
> interested in seeing the Tizzie glaze formulas they are in the Carlton
> Ball book "Making Pottery without a wheel". There are also lots of Cone
> 10 and cone 5 glazes in his book. The cone 10 glazes are very good.
>
>
>
> I am not trying to convince anyone of using lead, just pointing out how
> white lead was used by a contemporary potter at one time during his long
> illustrious career.
>
>
>
>
>
--
-e-in-o'side-
pagan by nature
>http://www.flickr.com/photos/42169721@N04/
Steve Mills on wed 18 may 11
On 17 May 2011, at 18:18, Bill Merrill wrote:
>=3D20
> The early English potters used lead. I wonder how many of those
> potters had health problems from the lead since they probably didn't
> know the hazards of lead.
>=3D20
>=3D20
>=3D20
They took it as one of the hazards of the job!=3D20
Some Manufacturer's paid attention to the risk, but there was no legal cont=
r=3D
ol on raw Lead use until the 1944 Potteries Act.=3D20
Fritted Lead became the norm after that, and was enforced rigerously by Fac=
t=3D
ories Act Inspectors.=3D20
We employees were all required to consume a pint of milk provided by the ow=
n=3D
ers every morning as a preventative!!!!
Steve M
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my Ipod touch
>=3D20
Edouard Bastarache on wed 18 may 11
Steve,
"We employees were all required to consume a pint of milk provided
by the owners every morning as a preventative!!!!
Steve M"
The Universal Antidote !!!
The 1,000 welders at our local shipyard were offered milk twice a day.
Since it was not worth S..., we convince the company to stop that and
use the money to buy safety boots instead; some were even working wearing
running shoes. And that was in 1979!!!
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://edouardbastarache.blogspot.com/
http://www.facebook.com/edouard.bastarache
http://blogsalbertbastarache.blogspot.com/
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my Ipod touch
>
ivor and olive lewis on thu 19 may 11
Suchman Ceramics,
Litharge is one of the oxides of Lead and will have adverse effects if
ingested or adsorbed.
Under the various headings, including Low Sol, Frank Hammer covers the topi=
c
pretty well. From my reading I would accept that the best starting point fo=
r
all who wish to use Lead as a low temperature glaze ingredient should emplo=
y
Lead Bisilicate Frit. This is stabilised to give minimal leaching by
incorporating Aluminium oxide in the melt.
From what I can gather Global production of Lead was more that 3.860.000
Tonnes in 2009 of which an estimated 3% was used by ceramic industries. Giv=
e
or take a few metric tons that would be near 115,800 tonnes of the metal.
But could be wrong, I am no statistician.
Regards,
Ivor Lewis,
REDHILL,
South Australia
Edouard Bastarache on thu 19 may 11
"High-Alumina Lead Bisilicates" are the least toxic.
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://edouardbastarache.blogspot.com/
http://www.facebook.com/edouard.bastarache
http://blogsalbertbastarache.blogspot.com/
----- Original Message -----
From: "ivor and olive lewis"
To:
Sent: Thursday, May 19, 2011 1:42 AM
Subject: Re: lead glazes
> Suchman Ceramics,
> Litharge is one of the oxides of Lead and will have adverse effects if
> ingested or adsorbed.
> Under the various headings, including Low Sol, Frank Hammer covers the
> topic
> pretty well. From my reading I would accept that the best starting point
> for
> all who wish to use Lead as a low temperature glaze ingredient should
> employ
> Lead Bisilicate Frit. This is stabilised to give minimal leaching by
> incorporating Aluminium oxide in the melt.
> From what I can gather Global production of Lead was more that 3.860.000
> Tonnes in 2009 of which an estimated 3% was used by ceramic industries.
> Give
> or take a few metric tons that would be near 115,800 tonnes of the metal.
> But could be wrong, I am no statistician.
> Regards,
> Ivor Lewis,
> REDHILL,
> South Australia
>
Edouard Bastarache on fri 20 may 11
Sorry Eric,
I do not teach.
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.flickr.com/photos/30058682@N00/
http://edouardbastarache.blogspot.com/
http://www.facebook.com/edouard.bastarache
http://blogsalbertbastarache.blogspot.com/
----- Original Message -----
From: "Eric Hansen"
To: "Edouard Bastarache"
Cc:
Sent: Friday, May 20, 2011 6:06 AM
Subject: Re: [Clayart] lead glazes
>I would absolutely NOT use lead ceramic materials around students -
> have you worked with students lately??? However if proper cautions
> are taken, the end result MIGHT be safe -
>
> - h -
>
>
> On Thu, May 19, 2011 at 1:02 PM, Edouard Bastarache
> wrote:
>> "High-Alumina Lead Bisilicates" are the least toxic.
>>
>> Gis,
>>
>> Edouard Bastarache
>> Spertesperantisto
>>
>> Sorel-Tracy
>> Quebec
>>
>> http://www.flickr.com/photos/30058682@N00/
>> http://edouardbastarache.blogspot.com/
>> http://www.facebook.com/edouard.bastarache
>> http://blogsalbertbastarache.blogspot.com/
>>
>>
>>
>>
>>
>> ----- Original Message -----
>> From: "ivor and olive lewis"
>> To:
>> Sent: Thursday, May 19, 2011 1:42 AM
>> Subject: Re: lead glazes
>>
>>
>>> Suchman Ceramics,
>>> Litharge is one of the oxides of Lead and will have adverse effects if
>>> ingested or adsorbed.
>>> Under the various headings, including Low Sol, Frank Hammer covers the
>>> topic
>>> pretty well. From my reading I would accept that the best starting poin=
t
>>> for
>>> all who wish to use Lead as a low temperature glaze ingredient should
>>> employ
>>> Lead Bisilicate Frit. This is stabilised to give minimal leaching by
>>> incorporating Aluminium oxide in the melt.
>>> From what I can gather Global production of Lead was more that 3.860.00=
0
>>> Tonnes in 2009 of which an estimated 3% was used by ceramic industries.
>>> Give
>>> or take a few metric tons that would be near 115,800 tonnes of the
>>> metal.
>>> But could be wrong, I am no statistician.
>>> Regards,
>>> Ivor Lewis,
>>> REDHILL,
>>> South Australia
>>>
>>
>
>
>
> --
> Eric Alan Hansen
> Stonehouse Studio Pottery
> Alexandria, Virginia
> americanpotter.blogspot.com
> thesuddenschool.blogspot.com
> hansencookbook.blogspot.com
> "Simplify, simplify, simplify" - Thoreau
>
Eric Hansen on fri 20 may 11
I would absolutely NOT use lead ceramic materials around students -
have you worked with students lately??? However if proper cautions
are taken, the end result MIGHT be safe -
- h -
On Thu, May 19, 2011 at 1:02 PM, Edouard Bastarache wr=
ote:
> "High-Alumina Lead Bisilicates" are the least toxic.
>
> Gis,
>
> Edouard Bastarache
> Spertesperantisto
>
> Sorel-Tracy
> Quebec
>
> http://www.flickr.com/photos/30058682@N00/
> http://edouardbastarache.blogspot.com/
> http://www.facebook.com/edouard.bastarache
> http://blogsalbertbastarache.blogspot.com/
>
>
>
>
>
> ----- Original Message -----
> From: "ivor and olive lewis"
> To:
> Sent: Thursday, May 19, 2011 1:42 AM
> Subject: Re: lead glazes
>
>
>> Suchman Ceramics,
>> Litharge is one of the oxides of Lead and will have adverse effects if
>> ingested or adsorbed.
>> Under the various headings, including Low Sol, Frank Hammer covers the
>> topic
>> pretty well. From my reading I would accept that the best starting point
>> for
>> all who wish to use Lead as a low temperature glaze ingredient should
>> employ
>> Lead Bisilicate Frit. This is stabilised to give minimal leaching by
>> incorporating Aluminium oxide in the melt.
>> From what I can gather Global production of Lead was more that 3.860.000
>> Tonnes in 2009 of which an estimated 3% was used by ceramic industries.
>> Give
>> or take a few metric tons that would be near 115,800 tonnes of the metal=
.
>> But could be wrong, I am no statistician.
>> Regards,
>> Ivor Lewis,
>> REDHILL,
>> South Australia
>>
>
--
Eric Alan Hansen
Stonehouse Studio Pottery
Alexandria, Virginia
americanpotter.blogspot.com
thesuddenschool.blogspot.com
hansencookbook.blogspot.com
"Simplify, simplify, simplify" - Thoreau
| |
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