Edouard Bastarache on sun 28 apr 02
=20
Hello John,
Here is also what I have said twice on Clayart recently:
=20
"As a general rule, the smaller the diameter of particles, the more
efficient is the pulmonary clearance by the bronchi and acini.=20
The bronchial and alveolar retention of particles is the result of=20
two opposing factors, deposition and clearance. Retention of dust=20
will be at its peak, depending on the nature of dust, for the particles=20
whose diameter ranges from 0.5 to 3 microns."
What is the equivalent in microns for mesh sizes?
I have never heard of any study concerning particle size distribution
in studio-potters' workshops, so it is very hard to conclude.
In the database I use most often, there is not a single case of
manganese-related neurological disorder described among pottery=20
workers or craftman/artists, and this chemical has been around for
quite many decades.
Let us be cautious but not alarmist.
Naturally there are smaller particles with the larger ones,
but I believe that most of the particles are large,
otherwise we would not use them to have specks.
Later,
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
=20
=20
=20
Ron Roy on wed 1 may 02
My answer was in response to a dark clay coloured with manganese and iron -
sounds like power to me - I do agree - the granular would not present to
same problem.
Just so everyone knows - they have choices to make and - some times -
prices to pay.
RR
>Naturally there are smaller particles with the larger ones,
>but I believe that most of the particles are large,
>otherwise we would not use them to have specks.
Ron Roy
RR #4
15084 Little Lake Road
Brighton
Ontario
Canada - K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Edouard Bastarache on wed 1 may 02
Hello Ron,
the first question asked on this matter was from Ababi and the use of =
0.2%=20
granular manganese in clays.
So, that is why I put some emphasis on the use of this granular material =
and I took this opportunity to give comprehensive information on =
different=20
toxicological aspects of manganese.
Later,
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
My answer was in response to a dark clay coloured with manganese and =
iron -
sounds like power to me - I do agree - the granular would not present to
same problem.
Just so everyone knows - they have choices to make and - some times -
prices to pay.
RR
>Naturally there are smaller particles with the larger ones,
>but I believe that most of the particles are large,
>otherwise we would not use them to have specks.
Ron Roy
RR #4
15084 Little Lake Road
Brighton
Ontario
Canada - K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
I would like to hear ( to read) from Edouard Bastarache.
You wrote about it last week, I think. I use granular manganese in one
of the claybodies I use, 0.2%. The way I do it is adding the manganeses
to a slurry of clay slip actually. I work lately a lot with paperclay,
so when it is wet, I add the manganese. no hands Electric drill. Ron
Roy offered me once to wash the manganese from the small particles, but
I did not succeed. In general, I think it is a very small amount.
Another question in the spirit of the days, Is this claybody can be
used for food? I know it might be sound a stupid question, but I prefer
to be stupid before rather than after
Ababi Sharon
Kibbutz Shoval- Israel
Glaze addict
ababisha@shoval.org.il
Ababi on fri 3 may 02
Even so you must be carful because there is dust in the granular shape.
Yet I add it to a slurry and mix with a drill . Ababi
---------- Original Message ----------
>Hello Ron,
>the first question asked on this matter was from Ababi and the use of
>0.2%
>granular manganese in clays.
>So, that is why I put some emphasis on the use of this granular
>material
>and I took this opportunity to give comprehensive information on
>different
>toxicological aspects of manganese.
>Later,
>Edouard Bastarache
>Irreductible Quebecois
>Indomitable Quebeker
>Sorel-Tracy
>Quebec
>edouardb@sorel-tracy.qc.ca
>http://sorel-tracy.qc.ca/~edouardb/
>http://perso.wanadoo.fr/smart2000/index.htm
>My answer was in response to a dark clay coloured with manganese and
>iron -
>sounds like power to me - I do agree - the granular would not present to
>same problem.
>Just so everyone knows - they have choices to make and - some times -
>prices to pay.
>RR
>>Naturally there are smaller particles with the larger ones,
>>but I believe that most of the particles are large,
>>otherwise we would not use them to have specks.
>Ron Roy
>RR #4
>15084 Little Lake Road
>Brighton
>Ontario
>Canada - K0K 1H0
>Phone: 613-475-9544
>Fax: 613-475-3513
>I would like to hear ( to read) from Edouard Bastarache.
>You wrote about it last week, I think. I use granular manganese in one
>of the claybodies I use, 0.2%. The way I do it is adding the manganeses
>to a slurry of clay slip actually. I work lately a lot with paperclay,
>so when it is wet, I add the manganese. no hands Electric drill. Ron
>Roy offered me once to wash the manganese from the small particles, but
>I did not succeed. In general, I think it is a very small amount.
>Another question in the spirit of the days, Is this claybody can be
>used for food? I know it might be sound a stupid question, but I prefer
>to be stupid before rather than after
>Ababi Sharon
>Kibbutz Shoval- Israel
> Glaze addict
>ababisha@shoval.org.il
>________________________________________________________________________
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