Dan Semler on mon 10 dec 07
Hi Richard,
I've had Jeff's Red tested and for the purpose of discussion it =20
leached 0.056 mg/L barium and 0.091 mg/L of copper. Please don't =20
assume my numbers and anyone else's are related to your own - not =20
speaking to you necessarily on this Richard but to anyone who reads =20
this. It was done on a specific body and a specific firing. People =20
need to have their glazes tested, fired in their own kiln on their own =20
body. All that said this is not a lot of either metal. Of course its a =20
well melted gloss glaze with very little barium carbonate in it to =20
begin with. Also remember that this test was an acid test. I have data =20
about extraction in an alkali solution such as would arise in a =20
dishwasher.
Hope this is of some help.
Thanx
D
> Hello again,
> In referring to my posting of Jeff Zamek's article on Barium Carbonate
> Toxicity and Use, I wonder if all of you barium users out there would be
> willing to share some information with the group.
> I don't necessary want you to share your glaze recipes, but rather whether
> or not you have had them tested for barium release, and whether the test
> results encouraged or discouraged you from using the glaze.
> If you have not had them tested, why not?
> Once again, I'm not backing any particular side in this debate, just tryin=
g
> to get some information flowing that can shed some light on the subject.
> Best,
> Richard Aerni
> Rochester, NY
>
> __________________________________________________________________________=
____
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, or change your
> subscription settings here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots2@visi.=
com
>
Richard Aerni on mon 10 dec 07
Hello again,
In referring to my posting of Jeff Zamek's article on Barium Carbonate
Toxicity and Use, I wonder if all of you barium users out there would be
willing to share some information with the group.
I don't necessary want you to share your glaze recipes, but rather whether
or not you have had them tested for barium release, and whether the test
results encouraged or discouraged you from using the glaze.
If you have not had them tested, why not?
Once again, I'm not backing any particular side in this debate, just trying
to get some information flowing that can shed some light on the subject.
Best,
Richard Aerni
Rochester, NY
John Sankey on tue 11 dec 07
To add to Richard's request, in the glaze database I am currently
marking all glazes with more than 10% molar barium as toxic, as
an initial precaution. I'd greatly appreciate having any
information that might help me to refine that to be as accurate
as possible. All glaze recipes that have been tested for barium
release would be welcome.
--
Include 'Byrd' in the subject line of your reply
to get through my spam filter.
John Hesselberth on tue 11 dec 07
Hi Richard,
For all practical purposes mg/L and ppm are the same thing. Just a
different name brought about when the scientific community tried to
standardize things a few year back.
Regards,
John
On Dec 11, 2007, at 6:42 PM, Richard Aerni wrote:
> I wonder if one of the scientists out there, or someone with the
> knowledge,
> would provide a conversion so that we can compare mg/Liter with p
> (arts)
> p(er) m(illion).
John Hesselberth
www.frogpondpottery.com
"Man is a tool-using animal....without tools he is nothing, with
tools he is all" .... Thomas Carlyle
pdp1@EARTHLINK.NET on tue 11 dec 07
Hi Rick,
I think you meant in place of the Baking Soda or Baking Powder -
The Cook's substitution, was more likely to have somehow used Barium
Carbonate ( in those days, likely called 'Witherite', and used in or as Rat
Poisons, as you say ) , in place of what at that time would have probably
been 'Saleratus', ( derived from a Root, then made synthetically, or
otherwise,
which was a form of Bi-Carbonate of Soda, or what we now call 'Baking
Soda' ), than to have used it in place of the Flour...
Then again, the substitution might have been intentional, too...as both
would have likely come in similar size and shape containers...
Possibly, the gesture or 'Rat Poison Bisquits' was poetic or
figurative...from the Cook's point of view.
As most of us know, it is not a good idea to offend a Cook...!
An interesting scene involving ( non-poison ) Bisuits...was in the Book "The
Hawkline Monster" by Richard Brautigan...not that is has to do with Barium,
but...just came to mind...
That was a good Book...
Phil
l v
----- Original Message -----
From: "Ric Swenson"
<<>>
I did some research at Dartmouth College Med School Library in the 1980s
and found scant evidence of toxic effects of Barium Carbonate. I wrote about
that to CLAYART in a posting in the early 1990s.
The only death documented in LANCET at that time happened in India many
years ago...turn of century? ....to an elderly British officer who was fed
Biscuits that mistakenly had been mixed by the native cook with Barium Carb.
instead of the labeled 'flour'. Several became ill...one died.
Barium Carb. was used as a rat poison...and in massive doses caused rats to
expire. Thus our fears?
>>>>snip<<<<
Ric
John Britt on tue 11 dec 07
Richard,
I would be happy to share.
I use barium carbonate in a blue celadon and have had it tested several
times at both Alfred Labs and Brandywine Labs with very low leach level. I
will have to look for the paperwork but I think it was definitely below
the levels for safe drinking water. One reason that the level is low is
that the glaze has plenty of silica and alumina. I have tried the same
glaze without it and the color was not as good or was sporadic.
Blue Celadon cone 10
25 Custer Feldspar
35 Silica
20 Whiting
20 Grolleg
1 Tin Oxide
2 Barium Carbonate
3 Barnard (optional)
Hope it helps,
John Britt
www.johnbrittpottery.com
Ric Swenson on tue 11 dec 07
=20
=20
I first became concerned about barium Carb during the 'Tylenol scare' many =
years ago. We (at Bennington Potters, Vermont) used 2 % in terracotta body=
to prevent scumming....and had the terracotta bakers checked for release. =
Trace only. No problem ...at that time. U.S Test Labs in PA did the testi=
ng I believe.
=20
I did some research at Dartmouth College Med School Library in the 1980s a=
nd found scant evidence of toxic effects of Barium Carbonate. I wrote about=
that to CLAYART in a posting in the early 1990s.
=20
The only death documented in LANCET at that time happened in India many yea=
rs ago...turn of century? ....to an elderly British officer who was fed Bi=
scuits that mistakenly had been mixed by the native cook with Barium Carb. =
instead of the labeled 'flour'. Several became ill...one died. =20
=20
Barium Carb. was used as a rat poison...and in massive doses caused rats to=
expire. Thus our fears?
=20
Barium Sulfate is used commonly to do Barium enemas to detect digestive dis=
orders I believe. Solubility is obviously different and now other tests ar=
e available other than x-rays?=20
=20
Can we hear from our Canadian Doctor friend?
=20
Not a good idea to ingest the material, and breathing any dust is harmful. =
=20
=20
Anyone else find incidents of toxicity documented by the medical community?=
Has it been tested,as lead was tested, for solubility in acidic solutions,=
etc.? We used to believe lead was not so harmful....now we know better.
=20
my 2 cents.
=20
Ric
=20
=20
"...then fiery expedition be my wing, ..." Wm. Shakespeare, RICHARD III, Ac=
t IV Scene III Richard H. ("Ric") Swenson, Teacher, Office of Internationa=
l Cooperation and Exchange of Jingdezhen Ceramic Institute, TaoYang Road, E=
astern Suburb, Jingdezhen City.JiangXi Province, P.R. of China. Postal code=
333001. Mobile/cellular phone :13767818872 < RicSwenson0823@hotmail.com>
> Date: Mon, 10 Dec 2007 22:27:10 -0500> From: raerni@ROCHESTER.RR.COM> Sub=
ject: Barium recipes...has anyone tested theirs?> To: CLAYART@LSV.CERAMICS.=
ORG> > Hello again,> In referring to my posting of Jeff Zamek's article on =
Barium Carbonate> Toxicity and Use, I wonder if all of you barium users out=
there would be> willing to share some information with the group.> I don't=
necessary want you to share your glaze recipes, but rather whether> or not=
you have had them tested for barium release, and whether the test> results=
encouraged or discouraged you from using the glaze.> If you have not had t=
hem tested, why not?> Once again, I'm not backing any particular side in th=
is debate, just trying> to get some information flowing that can shed some =
light on the subject.> Best,> Richard Aerni> Rochester, NY> > _____________=
_________________________________________________________________> Clayart =
members may send postings to: clayart@lsv.ceramics.org> > You may look at t=
he archives for the list, post messages, or change your> subscription setti=
ngs here: http://www.acers.org/cic/clayart/> > Moderator of the list is Mel=
Jacobson who may be reached at melpots2@visi.com
_________________________________________________________________
Share life as it happens with the new Windows Live.Download today it's FREE=
!
http://www.windowslive.com/share.html?ocid=3DTXT_TAGLM_Wave2_sharelife_1120=
07=
Edouard Bastarache Inc. on tue 11 dec 07
"Acute intoxications are rare and generally due to
suicidal attempts with the chloride or the
carbonate. Some cases of collective food
intoxications were reported, related to food
contamination, and to confusion between carbonate
and barium sulphate at the time of radiological
examinations. Barium carbonate having been
substituted accidentally for potato flour during
the preparation of sausages, 144 people were
poisoned in Israel in 1963. Two patients died."
Gis la revido,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.orange.fr/smart2000/livres.htm
http://www.pshcanada.com/Toxicology.htm
http://www.ceramique.com/librairie/
http://www.flickr.com/photos/30058682@N00/
http://myblogsmesblogs.blogspot.com/
----- Original Message -----
From: "Ric Swenson"
To:
Sent: Tuesday, December 11, 2007 2:11 AM
Subject: Re: Barium recipes...has anyone tested
theirs?
I first became concerned about barium Carb during
the 'Tylenol scare' many years ago. We (at
Bennington Potters, Vermont) used 2 % in
terracotta body to prevent scumming....and had the
terracotta bakers checked for release. Trace
only. No problem ...at that time. U.S Test Labs
in PA did the testing I believe.
I did some research at Dartmouth College Med
School Library in the 1980s and found scant
evidence of toxic effects of Barium Carbonate. I
wrote about that to CLAYART in a posting in the
early 1990s.
The only death documented in LANCET at that time
happened in India many years ago...turn of
century? ....to an elderly British officer who
was fed Biscuits that mistakenly had been mixed by
the native cook with Barium Carb. instead of the
labeled 'flour'. Several became ill...one died.
Barium Carb. was used as a rat poison...and in
massive doses caused rats to expire. Thus our
fears?
Barium Sulfate is used commonly to do Barium
enemas to detect digestive disorders I believe.
Solubility is obviously different and now other
tests are available other than x-rays?
Can we hear from our Canadian Doctor friend?
Not a good idea to ingest the material, and
breathing any dust is harmful.
Anyone else find incidents of toxicity documented
by the medical community? Has it been tested,as
lead was tested, for solubility in acidic
solutions, etc.? We used to believe lead was not
so harmful....now we know better.
my 2 cents.
Ric
"...then fiery expedition be my wing, ..." Wm.
Shakespeare, RICHARD III, Act IV Scene III
Richard H. ("Ric") Swenson, Teacher, Office of
International Cooperation and Exchange of
Jingdezhen Ceramic Institute, TaoYang Road,
Eastern Suburb, Jingdezhen City.JiangXi Province,
P.R. of China. Postal code 333001. Mobile/cellular
phone :13767818872 < RicSwenson0823@hotmail.com>
> Date: Mon, 10 Dec 2007 22:27:10 -0500> From:
> raerni@ROCHESTER.RR.COM> Subject: Barium
> recipes...has anyone tested theirs?> To:
> CLAYART@LSV.CERAMICS.ORG> > Hello again,> In
> referring to my posting of Jeff Zamek's article
> on Barium Carbonate> Toxicity and Use, I wonder
> if all of you barium users out there would be>
> willing to share some information with the
> group.> I don't necessary want you to share your
> glaze recipes, but rather whether> or not you
> have had them tested for barium release, and
> whether the test> results encouraged or
> discouraged you from using the glaze.> If you
> have not had them tested, why not?> Once again,
> I'm not backing any particular side in this
> debate, just trying> to get some information
> flowing that can shed some light on the
> subject.> Best,> Richard Aerni> Rochester, NY> >
> ______________________________________________________________________________>
> Clayart members may send postings to:
> clayart@lsv.ceramics.org> > You may look at the
> archives for the list, post messages, or change
> your> subscription settings here:
> http://www.acers.org/cic/clayart/> > Moderator
> of the list is Mel Jacobson who may be reached
> at melpots2@visi.com
_________________________________________________________________
Share life as it happens with the new Windows
Live.Download today it's FREE!
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______________________________________________________________________________
Clayart members may send postings to:
clayart@lsv.ceramics.org
You may look at the archives for the list, post
messages, or change your
subscription settings here:
http://www.acers.org/cic/clayart/
Moderator of the list is Mel Jacobson who may be
reached at melpots2@visi.com
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Richard Aerni on tue 11 dec 07
Hi Dan,
This will expose my ignorance for all to see, but I'm no expert on any of
this...just an interested observor!
I wonder if one of the scientists out there, or someone with the knowledge,
would provide a conversion so that we can compare mg/Liter with p(arts)
p(er) m(illion).
Best,
Richard
On Mon, 10 Dec 2007 22:41:03 -0600, Dan Semler wrote:
>Hi Richard,
>
> I've had Jeff's Red tested and for the purpose of discussion it
>leached 0.056 mg/L barium and 0.091 mg/L of copper. Please don't
>assume my numbers and anyone else's are related to your own - not
>speaking to you necessarily on this Richard but to anyone who reads
>this. It was done on a specific body and a specific firing. People
>need to have their glazes tested, fired in their own kiln on their own
>body. All that said this is not a lot of either metal. Of course its a
>well melted gloss glaze with very little barium carbonate in it to
>begin with. Also remember that this test was an acid test. I have data
>about extraction in an alkali solution such as would arise in a
>dishwasher.
>
>Hope this is of some help.
>Thanx
>D
>
Dan Semler on tue 11 dec 07
Hi Richard,
Many web refs suggest these are the same thing mg/L and ppm. One
more technical site suggested they are "somewhat similar". But if
consider the relative density of the thing your testing for and the
solution its in then they'd differ. 1 mg/Kg is 1 ppm if its all the
same liquid. 1kG of water is a litre, so 1 ppm is 1mg/L if its all
water. So I would say that there would have to be a correction to take
density into account but I don't know the details myself. A post at
onlineconversion.com does use the relative density to perform the
conversion.
Having said that I looked at the results from the lab and they
appear to consider ppm and mg/L equivalent. This seems odd to me so
perhaps one of the chemists here could explain why relative density
can be neglected. If it can't be then perhaps this is simply a
convenience shorthand that is commonly used but not actually correct.
Anyone ?
thx
D
John Hesselberth on tue 11 dec 07
Hi Richard,
The most extensive work in this area I am aware of was done by Janet
DeBoos and was published on page 66-77 of Ceramics Technical, issue
3, 1996. She found that very stable barium containing glazes could be
made, but also that some leached very badly. She measured barium
leaching as low as 0.02 ppm and as high as 258 ppm in the 30 samples
that are detailed in the article. In general -- and I am paraphrasing
here -- she found that if you have enough silica and alumina and
fire hot enough barium leaching levels are fairly low. She did not
reach a definitive conclusion on the importance of barium level
itself. Too many other things were being changed at the same time.
To me this was a good initial study which pointed to the opportunity
to do so more designed experimentation.
It is one of the very few articles in the literature, though, where
anyone has studied the leaching of anything other than lead. I think
it is too bad the study has not received more publicity--in my
opinion it should be required reading for anyone who uses barium in
their glazes.
Regards,
John
On Dec 10, 2007, at 10:27 PM, Richard Aerni wrote:
> Hello again,
> In referring to my posting of Jeff Zamek's article on Barium Carbonate
> Toxicity and Use, I wonder if all of you barium users out there
> would be
> willing to share some information with the group.
> I don't necessary want you to share your glaze recipes, but rather
> whether
> or not you have had them tested for barium release, and whether the
> test
> results encouraged or discouraged you from using the glaze.
> If you have not had them tested, why not?
> Once again, I'm not backing any particular side in this debate,
> just trying
> to get some information flowing that can shed some light on the
> subject.
> Best,
> Richard Aerni
> Rochester, NY
>
> ______________________________________________________________________
> ________
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, or change
> your
> subscription settings here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com
John Hesselberth
www.frogpondpottery.com
"Man is a tool-using animal....without tools he is nothing, with
tools he is all" .... Thomas Carlyle
Ivor and Olive Lewis on wed 12 dec 07
Dear Richard Aerni,
Most theories have a life span equal to the life of the last person to =
adopt them before they are superseded. Everything is subject to =
refutation. Even if that is difficult to accomplish we should retain our =
scepticism. After all, there may be a flock of White Crows in the =
paddock over the hill. Just because all the Crows we have seen are black =
is no proof white ones do not exist. Scepticism is a healthy pastime.
About Concentrations.... Milligrams per litre represent things in =
Aqueous Solution. Approximately one litre of water weighs a =
kilogram...1000 grams......1,000,000 milligrams. So one milligram per =
litre is one part per million. At Olympic Dam they are recovering Gold =
at the rate of 3 grams per metric tonne of spoil, 3 parts per million.
Enjoy the day,
Best regards,
Ivor
Ric Swenson on wed 12 dec 07
Yes....whitherite...I remember that word...rat poison.
=20
maybe the substitution was an accident of language/reading.... or whatever.=
...the cook's idea.....by accident because he didn't speak English or becau=
se he hated the British?
=20
=20
the point is that is caused toxic problems for those soldiers. So read fo=
r yourself in LANCET.=20
=20
The Canadian Doctor Edouarde....has now offered another example from 1963 =
Israeli army experiences.
=20
I am not a professional cook nor do I pretend to be....just a simple potter=
.
=20
Flour......baking soda...powder? who gives a sh..?
=20
a me es egual.=20
=20
an ingredient....so it affected the eaters.
=20
HA!
=20
picky picky picky
=20
Barium can cause problems...... no matter what you call the ingredient you=
intended.
=20
Right...never offend the cook!!.
=20
Ric> > I think you meant in place of the Baking Soda or Baking Powder -> > =
The Cook's substitution, was more likely to have somehow used Barium> Carbo=
nate ( in those days, likely called 'Witherite', and used in or as Rat> Poi=
sons, as you say ) , in place of what at that time would have probably> bee=
n 'Saleratus', ( derived from a Root, then made synthetically, or> otherwis=
e,> which was a form of Bi-Carbonate of Soda, or what we now call 'Baking> =
Soda' ), than to have used it in place of the Flour...> > > Then again, the=
substitution might have been intentional, too...as both> would have likely=
come in similar size and shape containers...> > Possibly, the gesture or '=
Rat Poison Bisquits' was poetic or> figurative...from the Cook's point of v=
iew.> > > As most of us know, it is not a good idea to offend a Cook...!> >=
> An interesting scene involving ( non-poison ) Bisuits...was in the Book =
"The> Hawkline Monster" by Richard Brautigan...not that is has to do with B=
arium,> but...just came to mind...> > > That was a good Book...> > > > Phil=
> l v> > > ----- Original Message -----> From: "Ric Swenson"> > > > > <<ip>>>> > I did some research at Dartmouth College Med School Library in the=
1980s> and found scant evidence of toxic effects of Barium Carbonate. I wr=
ote about> that to CLAYART in a posting in the early 1990s.> > The only dea=
th documented in LANCET at that time happened in India many> years ago...tu=
rn of century? ....to an elderly British officer who was fed> Biscuits that=
mistakenly had been mixed by the native cook with Barium Carb.> instead of=
the labeled 'flour'. Several became ill...one died.> > Barium Carb. was us=
ed as a rat poison...and in massive doses caused rats to> expire. Thus our =
fears?> > >>>>snip<<<<> > > Ric> > ________________________________________=
______________________________________> Clayart members may send postings t=
o: clayart@lsv.ceramics.org> > You may look at the archives for the list, p=
ost messages, or change your> subscription settings here: http://www.acers.=
org/cic/clayart/> > Moderator of the list is Mel Jacobson who may be reache=
d at melpots2@visi.com
_________________________________________________________________
Get the power of Windows + Web with the new Windows Live.
http://www.windowslive.com?ocid=3DTXT_TAGHM_Wave2_powerofwindows_122007=
Ivor and Olive Lewis on wed 12 dec 07
Dear John Sankey,
You say <<.... am currently marking all glazes with more than 10% molar =
barium as toxic, as an initial precaution. >>.
Precisely what does that mean ? Is that one tenth of the gram molecular =
mass, that is 13.7 grams of elemental Barium in the batch of glaze, or =
are you speaking of the oxide (15.3 g)or the usual commercial =
ingredient, Barium carbonate (19.7 g).
Knowing that it is possible to make transparent glossy glazes contain =
20% or more Barium Carbonate I would like to know your reasons for =
making such a sweeping generalisation.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
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