Cathleen McGowan on sat 7 nov 98
------------------
Hello
I am a potter/sculptor who sometimes uses wet lead commercial glazes i.e.
Duncan. My toxic kiln is in a shed which people rarely stay in. I never =
fire
dinnerware in this kiln. However, what is the risk of firing items such as =
oil
candle lamps and massage oil bottles in it. If one covers the inside =
surface
with a watersealing agent such as Thompson's, after firing, does this help
minimize exposure? Are the fired items safe to even handle? What can I do =
to
protect myself from the glazes besides gloves and a smock? How much =
exposure is
really bad?
-Wondering
Cat cmcgowan2=40loyola.edu
Bob Wicks on sun 8 nov 98
Cathleen:
I suggest that you get in touch with Monona Rossol regarding the use of lead
glazes. I just threw out 40 bottles of lead glazes and our Art Center is in
the process of forming a policy of absolutely no lead glazes. You are the one
that is in the most dangerous position because you are working with glazes
every day. Once lead glaze gets spilled on the floor and is ground in the
dusty foot prints, you are putting your self in jeopardy. For the most part
lead stays in the system and is not excreted like other substances, so it is
accumulative. If you place your good fortune of a healthy life at risk, that
is a decision you must make.
Monona Rossol's address is 75054.2542@CompuServe.com
Bobwicks@aol.com
Earl Krueger on sun 21 dec 03
I did a google search for "Lead test kits" and found;
http://www.dhs.cahwnet.gov/childlead/tableware/twtest.html
Here's what they have to say:
Quote:
The only way to determine if certain tableware represents a lead hazard
is to test it for lead. This includes tableware that is:
> purchased outside of the United States
> hand-crafted
> older or no longer available for purchase
> purchased in a small independent retail
outlet (like a neighborhood store)
> acquired in any other situation where the
manufacturer cannot be contacted
End quote:
Which of the above DO NOT describe studio potters?
Which DO describe large corporate manufacturers?
Why the difference?
This is an image problem that can not be ignored !!
Damned soap box came out again.
Earl...
Bothell, WA, USA
Nancy Udell on thu 9 dec 04
Date: Thu, 9 Dec 2004 10:39:20 -0600
From: Kate Johnson
Subject: Re: lead in traditional honey glaze
> You said they were new books. What is or are their copyright dates?
Hello all,
Robbin Hopper's Ceramic Spectrum also includes recipes for lead glazes,
and his brand new book Making Marks (2004) includes a sensible
discussion of lead the use of lead. Just like everything else, it
should be used with full understanding of the dangers and not on
functional ware. But it can be used for getting quite vibrant colors
that cannot (according to Robin Hopper) otherwise be achieved.
Consider Aaron Wildavsky's interesting statement: "The secret of safety
lies in danger." Perhaps if we attempt to eliminate all risk, then we
grow inept at navigating danger and lose in the process some of life's
richness.
Nancy, in Maryland and gearing up for massive sculptural glaze testing
phase with certain Brian Gartside inspired ideas that may very well
include lead.....
Jon Pacini on fri 10 dec 04
Greetings All-- Hi Nancy-- you wrote
Robbin Hopper's Ceramic Spectrum also includes recipes for lead glazes,
and his brand new book Making Marks (2004) includes a sensible
discussion of lead the use of lead. Just like everything else, it
should be used with full understanding of the dangers and not on
functional ware. But it can be used for getting quite vibrant colors
that cannot (according to Robin Hopper) otherwise be achieved.
I m glad to see someone with the stature of Robin Hopper has included this
in his new book. It will add some fuel to the fire. I ll have to get copy
and see what he has to say---thanks.
Best regards
Jon Pacini
Clay Manager
Laguna Clay Co.
Ron Roy on sat 11 dec 04
And perhaps the secret to danger lies in safety.
What you do to yourself is one thing - but are we right to subject others
to danger - without them knowing - so they or we might be safer?
Most of what I read about lead in pottery books indicates a lack of
understanding about this material - before advising others we should know
what we are talking about. The result is - most potters are not fully
informed about toxicity, glaze stability and the dangers of fuming in our
kilns.
We should know what the possible dangers are and which are serious - so we
can make informed choices for ourselves and others.
Messing with carcinogens for instance - what safety do we find in that danger?
RR
>Consider Aaron Wildavsky's interesting statement: "The secret of safety
>lies in danger." Perhaps if we attempt to eliminate all risk, then we
>grow inept at navigating danger and lose in the process some of life's
>richness.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Url Krueger on sat 11 dec 04
I don't know about the rest of you but when
I put 1000g of frit in a glaze I never end
up with all of that 1000g being on my pots.
Some goes down the drain, some gets scraped
up and put in the trash and I'm sure some
gets in the dust on my shoes and tracked
around.
So, if that frit contained appreciable
quantities of lead then I would be polluting
the drainage system, which in my case is the
back yard, my garbage can, the dump truck,
the dump site, my studio and my house.
I'm not willing to do that just to obtain a
certain look in a glaze.
Some say that you can not achieve that look
in any other way. I don't believe that. I
think we have just not yet learned how to
do it. Test, test, test, ....
Earl...
--
Earl K...
Bothell WA, USA
"You may be disappointed if you fail,
but you are doomed if you don't try."
Beverly Sills (1929 - )
pdp1@EARTHLINK.NET on sat 11 dec 04
Hi Ron, all...
My own fantasies, or other thoughts, see me one day having
two kilns...
One, for the exclusive fireing of Works which may be for the
table...
The other, for Works which will not be for the table, and
these, may include the use of Glazes which contain Lead or
other ingredients which prudence recommends be kept from our
foods and beverages.
Too, vessels which may have a Lead Glaze on their outsides,
need not have a lead Glaze on their insides, where, we may
wonder then how to protect the insides form the vapors in
fireing, when the outside Glaze does have something to it
which we do not want any of on the inside.
I aspire one day, to make Ink Wells, humane Roach-Traps,
Insense Burners, curious small totems or other figurines,
and whatever other arcane little charmers, whose Glazes will
be any number old faithful ash, and dug from-the-earth,
combines.
And I will keep these in their own Kiln, so ambient
re-animated vapors of the Kiln's history itself, may stay
where they belong, with the class of Work I intend them for.
...whatcha think?
Love,
Phil
el ve
----- Original Message -----
From: "Ron Roy"
> And perhaps the secret to danger lies in safety.
>
> What you do to yourself is one thing - but are we right to
subject others
> to danger - without them knowing - so they or we might be
safer?
>
> Most of what I read about lead in pottery books indicates
a lack of
> understanding about this material - before advising others
we should know
> what we are talking about. The result is - most potters
are not fully
> informed about toxicity, glaze stability and the dangers
of fuming in our
> kilns.
>
> We should know what the possible dangers are and which are
serious - so we
> can make informed choices for ourselves and others.
>
> Messing with carcinogens for instance - what safety do we
find in that danger?
>
> RR
>
>
>
>
> >Consider Aaron Wildavsky's interesting statement: "The
secret of safety
> >lies in danger." Perhaps if we attempt to eliminate all
risk, then we
> >grow inept at navigating danger and lose in the process
some of life's
> >richness.
>
> Ron Roy
> RR#4
> 15084 Little Lake Road
> Brighton, Ontario
> Canada
> K0K 1H0
> Phone: 613-475-9544
> Fax: 613-475-3513
>
>
____________________________________________________________
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at melpots@pclink.com.
Ron Roy on mon 13 dec 04
Hi Phil,
The only thing I can think of is a cover - so even if the kiln is
contaminated the inside would not get a coating. Maybe make the cover into
a roach trap and sell it separately - or with the pot as the inside will be
lead free if there is a lead free glaze on it. Can't be a humane trap if
it's lead glazed inside though.
All this about leaching lead glazes and I know they can be made not to
leach significant amounts - just don't know any potters who know how to do
it.
Interesting article I was reading today - how some French made dinnerware
was poisoning a 10 year old - seems abrasion was affecting the glaze enough
to allow leaching into food. Tricky business this pottery.
I like the "ambient re-animated vapors of the Kiln's history " - potters
will know what you are talking about - I think!
Best regards Phil - see you in Baltimore - a long drive this time - RR
>My own fantasies, or other thoughts, see me one day having
>two kilns...
>
>One, for the exclusive fireing of Works which may be for the
>table...
>
>
>The other, for Works which will not be for the table, and
>these, may include the use of Glazes which contain Lead or
>other ingredients which prudence recommends be kept from our
>foods and beverages.
>
>Too, vessels which may have a Lead Glaze on their outsides,
>need not have a lead Glaze on their insides, where, we may
>wonder then how to protect the insides form the vapors in
>fireing, when the outside Glaze does have something to it
>which we do not want any of on the inside.
>
>I aspire one day, to make Ink Wells, humane Roach-Traps,
>Insense Burners, curious small totems or other figurines,
>and whatever other arcane little charmers, whose Glazes will
>be any number old faithful ash, and dug from-the-earth,
>combines.
>
>And I will keep these in their own Kiln, so ambient
>re-animated vapors of the Kiln's history itself, may stay
>where they belong, with the class of Work I intend them for.
>...whatcha think?
>Love,
>Phil
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
bonnie staffel on tue 14 dec 04
I traveled to China back in the 70's with an art tour of several cities.
This was back when China first opened their country to visitors. At each
commune center they set up a visitor's shop which showed the handiwork of
that area. One particular commune interested me very much as it was wher=
e
the famous multicolored horse statues were being reproduced. The room wa=
s
full of tables with decorators sitting side by side, a horse being
decorated in front of them, a tea cup with tea on the table and a brush.
They were coating the horses with what looked to me like red lead. This
powder was all over the floor and tables, no ware boards were used so eac=
h
horse had to be handled to take it to the next station. No precautions w=
ere
being taken for the decorators' safety. Many times I heard that the peop=
le
were expendable.
Young teenage girls were taught the fine art of embroidery on silk and wh=
en
their eyes deteriorated new teenagers took their place. The Cloisonn=E9
demonstration factory was fascinating as well with the tiny raised copper
walls holding probably lead based enamels. A Jade factory showed the
intricate work of that grinding by Chinese artisans. No attention to
personal safety with masks here either. On one stop my friend and I brok=
e
away from the planned stop to visit a real department store a short dista=
nce
away. I was looking for a hat so with sign language indicating what I wa=
s
looking for, size, price, came back to the tour bus with my hat in hand.
I have no plans of ever revisiting China but there are those of you who h=
ave
in more recent years. Can you set me straight as to whether their artist=
s
are being protected better now?
Warm regards,
Bonnie Staffel
http://webpages.charter.net/bstaffel/
http://vasefinder.com/bstaffelgallery1.html
Charter Member Potters Council
Jackson Gray on sun 15 may 11
While we're on the subject... I had a pitcher with a cone 10 glaze that
I wasn't too happy with, so I reglazed it with a commercial low fire
glaze and refired it to cone 06. It is lovely - however the glaze I
used has lead in it - silly me, I thought they had all been taken off
the shelves years ago. My first indication was to take a hammer to it,
since it is a functional piece albeit lovely, but after reading your
comments, I wonder if it is worth sending it to the lab to test for
leaching. Do you all think it might be food safe after all? Worth the
test? The glaze is all gone and discontinued (now I guess my earlier
presumption might be correct) and the pot is probably never going to be
worth the additional cost of the test - but like I said, it is lovely.
Thanks for you input,
Jackson
www.jackpots-pottery.com
Paul Lewing on mon 16 may 11
On May 15, 2011, at 10:42 PM, Jackson Gray wrote:
While we're on the subject... I had a pitcher with a cone 10 glaze that
I wasn't too happy with, so I reglazed it with a commercial low fire
glaze and refired it to cone 06.
Did you put that glaze on the inside or just on the outside? It
matters not at all what's on the outside.
Paul Lewing
www.paullewingtile.com
www.paullewingart.com
David Finkelnburg on tue 17 may 11
Jackson,
You ask a good question! I suspect that every person on this list has
eaten and drunk, at one time or another and more likely many, many times,
from lead-glazed dishes and cups. Commercial manufacturers in the US, under
close scrutiny by both federal and state agencies, produced a lot of
unquestionably foodsafe "hotel China" that used lead in the glazes. At leas=
t
one manufacturer I am aware of still does.
Lead got bad press because of its potential hazard to people mixing an=
d
applying the glazes, and because of misuse (usually out of ignorance or
inability to control firing temperatures) in small, unregulated potteries.
Classic cases with low-fire ware made in Mexico and central America got a
lot of publicity because bad news sells so well. Same media has given
little coverage to the extensive outreach by American artists and scientist=
s
to Mexican and central American potteries teaching how to make low-fire
glazes using boron instead of lead...but that's a different rant! :-)
So, if you used a properly formulated glaze and fired it high enough t=
o
melt fully it is quite possibly foodsafe. What you do with it now is
something only you can say.
Dave Finkelnburg
http://www.mattanddavesclays.com
-------------------------
On Sun, 15 May 2011 22:42:34 -0700, Jackson Gray
wrote: I had a pitcher with a cone 10 glaze that
I wasn't too happy with, so I reglazed it with a commercial low fire
glaze and refired it to cone 06. It is lovely - however the glaze I
used has lead in it - silly me, I thought they had all been taken off
the shelves years ago. My first indication was to take a hammer to it,
since it is a functional piece albeit lovely, but after reading your
comments, I wonder if it is worth sending it to the lab to test for
leaching. Do you all think it might be food safe after all? Worth the
test? The glaze is all gone and discontinued (now I guess my earlier
presumption might be correct) and the pot is probably never going to be
worth the additional cost of the test - but like I said, it is lovely.
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