Ron Roy on wed 10 dec 03
Hi Stephen,
The fumes are the biggest danger - but that fuming manganese will condence
out on all surfaces as it cools - that means all the dust lying around is
contaminated with manganese - when there is air movement the contaminated
dust becomes airborn and is a problem again - and again and again. How long
you spend in that area becomes the factor to how much you are exposed to.
So it's not just the fumes.
I heard someone say here - but they are putting Manganese in gas - I don't
know if the implication was that it was not a danger - I think it is and it
will eventually be banned. Spraying it all over the place with auto
emmissions is probably the best way to contaminate everything.
Think back - they used to put lead in gas - they thought that was safe -
actually did the testing - turns out the instruments they used to measure
the problem were not sensitive enough - so thay say.
Read Monona's book - she lists the symptoms - once it starts you can't stop
it - degenerative nerve disease. There have been a few potters on this list
who think they have it - had to give up pottery - David Shaner thought
Manganese is what killed him.
RR
>So what are the dangers of manganese? I mean the actual results of
>manganese poisoning? Would the fumes linger after several hours of cooling?
>Stephen
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 wed 10 dec 03
Ron,
checking Quebec's exposure limits for manganese we find that fumes
are about 5 times more toxic than dust:
1-Manganese Fumes = 1 mg/m3
2-Manganese Dust = 5 mg/m3.
So, it depends on many factors, if we refer to the study conducted in BC
where all of the studios had some kind of ventilation, and even in studios
not
very well ventilated but ventilated, the exposure was nearly insignificant
when compared to exposure limits. The data published were in "µgs"
not in "mgs". 1 µg =1/1000th of a mg.
Maybe BCfers are more disciplined than us when it comes to using
ventilation.
Later,
"Ils sont fous ces quebecois"
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
http://www.digitalfire.com/education/toxicity/
Ron Roy on sat 13 dec 03
And maybe the work areas were extra ventilated because they knew they were
going to be tested - and maybe the accumulated condenced manganese from the
fuming which had accumulated over the years was not sampled.
Maybe there was very little manganese being used in the glazes and clay.
Maybe the equipment used to measure the manganese was not state of the art.
I say - don't be lulled into thinking it's safe because you like using
manganese. It is a very serious toxin and you can't undo the results to
your health.
If you want to believe that there are no problems with government limits
that is up to you - but understand - governments guess low until the uproar
is so loud they have to change em.
RR
>checking Quebec's exposure limits for manganese we find that fumes
>are about 5 times more toxic than dust:
>1-Manganese Fumes =3D 1 mg/m3
>2-Manganese Dust =3D 5 mg/m3.
>
>So, it depends on many factors, if we refer to the study conducted in BC
>where all of the studios had some kind of ventilation, and even in studios
>not
>very well ventilated but ventilated, the exposure was nearly insignificant
>when compared to exposure limits. The data published were in "=B5gs"
>not in "mgs". 1 =B5g =3D1/1000th of a mg.
>
>Maybe BCfers are more disciplined than us when it comes to using
>ventilation.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
=46ax: 613-475-3513=20
Edouard Bastarache Inc. on sun 14 dec 03
"And maybe the work areas were extra ventilated because they knew they were
going to be tested - and maybe the accumulated condenced manganese from the
fuming which had accumulated over the years was not sampled.(RR)"
A-I have no reason to doubt the sincerity, honesty and knowledge of the
people who
conducted this research. Most of the authors belonged to the Department of
Health Care and Epidemiology of the University of British Columbia and one
belonged to the Occupational Hygiene Program of the same university. This
project was funded by the British Columbia Medical Services Foundation.
As you see it was not funded by some industrialists or capitalist
organizations.
The workplaces and potters sampled had nothing to do with any type of
ownership in the hands of investors.
The ceramists sampled worked in 5 categories of workplaces:
-professional studios,
-recreation centres,
-elementary schools,
-secondary schools,
-colleges.
I do not think that any of these ceramists had any interest in
over-ventilating
their workplaces during the study, it was in their personal interest to
participate
in a project defined to establish their exposure to a myriad of chemicals in
order to improve their working conditions.
B-Now, as for the deposited manganese on different surfaces in workshops my
answer is that what counts is the amount inhaled. (EB)
"Maybe there was very little manganese being used in the glazes and
clay.(RR)"
They had the freedom to use the amounts of manganese they wanted to use.(EB)
"Maybe the equipment used to measure the manganese was not state of the
art.(RR)"
I also doubt that very much, the chemical analyses were done by the
University of British Columbia Occupational Hygiene Laboratory, not a
capitalist contractor.EB
"I say - don't be lulled into thinking it's safe because you like using
manganese. It is a very serious toxin and you can't undo the results to
your health.RR"
Well, I know more about the toxicology of manganese than you do. You
probably know
more than me in ceramics technology but, we are talking toxicology in this
post.EB.
"If you want to believe that there are no problems with government limits
that is up to you - but understand - governments guess low until the uproar
is so loud they have to change em.RR"
The lawmakers in our specialty always base their decisions on specialists
teaching at our universities or working for government agencies, these
people are not paid by the industrialists.EB
Later,
"Ils sont fous ces quebecois"
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
http://www.digitalfire.com/education/toxicity/
Kathi LeSueur on mon 15 dec 03
edouardb@SOREL-TRACY.QC.CA wrote:
>"And maybe the work areas were extra ventilated because they knew they were
>going to be tested - and maybe the accumulated condenced manganese from the
>fuming which had accumulated over the years was not sampled.(RR)"
>
>A-I have no reason to doubt the sincerity, honesty and knowledge of the
>people who conducted this research......
>
>B-Now, as for the deposited manganese on different surfaces in workshops my
>answer is that what counts is the amount inhaled. (EB)>>>>
>
I alway pay attention to the discussions on manganese since my most
popular glaze uses this chemical. After years of listening to the
discussions I have to come down on the side of Edouard for the following
reason.
In 1998 I lost my sense of smell. A brain tumor was ruled out (in the
process they did find I had a brain-something others had questioned). So
they started to look at my work environment. I mentioned the concerns of
manganese poisoning so they consulted a toxicologist. She decided to
test for it and other heavy metals. By then I had been using this glaze
in the studio for ten years. The tests all came back negative.
I believe that all materials can be used safely if good studio practices
are applied. My glaze area is totally separated from the throwing area.
I damp mop often. Never sweep. I have excellent ventilation. A large
hood over the kiln and two turbines in the roof that take away
additional heat and fumes. The over head doors can be opened and the
whole are hosed and scrubbed.
I don't take toxic materials lightly, but neither do I let them control
my life. Common sense is key.
Kathi
>
>
>
Ron Roy on thu 18 dec 03
Hi Kathi,
I never said it was not possible to work with toxic materials in a safe way
- but you need to know about their toxicity so you can take the proper
precauctions.
Will you tell us where you learned that manganese is dangerous?
I got a phone call from a woman in California yesterday - urging me to keep
posting on this subject.
She used to work with a Manganese glaze - used to scrape it off the rims -
which produced dust. She now has Parkinsons and tremors and restless legs -
and is sure it came from working with Manganese. She is in her mid 60's so
it looks like her disability is not attributable to old age.
I have asked her to write about her experience and post it to ClayArt but
she does not have much energy and it will be difficult for her.
RR
> I alway pay attention to the discussions on manganese since my most
>popular glaze uses this chemical. After years of listening to the
>discussions I have to come down on the side of Edouard for the following
>reason.
>
>In 1998 I lost my sense of smell. A brain tumor was ruled out (in the
>process they did find I had a brain-something others had questioned). So
>they started to look at my work environment. I mentioned the concerns of
>manganese poisoning so they consulted a toxicologist. She decided to
>test for it and other heavy metals. By then I had been using this glaze
>in the studio for ten years. The tests all came back negative.
>
>I believe that all materials can be used safely if good studio practices
>are applied. My glaze area is totally separated from the throwing area.
>I damp mop often. Never sweep. I have excellent ventilation. A large
>hood over the kiln and two turbines in the roof that take away
>additional heat and fumes. The over head doors can be opened and the
>whole are hosed and scrubbed.
>
>I don't take toxic materials lightly, but neither do I let them control
>my life. Common sense is key.
>
>Kathi
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 fri 19 dec 03
Hello Brian,
it is not an easy task to diagnose Manganism
Here is a proposition for the medical surveillance
and diagnosis of this disease.
I would like to know more about the medical file
of this lady before concluding:
Medical surveillance :
Often times the only aid to diagnosis is a history of manganese exposure.
1-Pre-employment medical examination :
It aims at searching for the presence of a neurological and/or pulmonary
impairment likely to
be worsened by exposure to manganese, and it will be used as reference
making it possible
to better analyze the results of periodical examinations.
Here are some suggested elements;
1-Complete history taking and physical examination,
2-Neurological assessment,
3-Spirometry,
4-A few psychomotor tests(for instance: evaluation of extremities tremor and
reaction
(response) time
5-Blood and urinary manganese measurements.
2-Periodical examination :
Its frequency depends on the severity of exposure and on the legislation in
force. It consists
in seeking, if possible, with the aid of a well standardized questionnaire,
early symptoms of
neuropsychological and pulmonary impairment, in repeating the pre-employment
examinations
and comparing them with the latter in order to detect any risk of excessive
impregnation .
It is important to practise this comparison, not only at the individual
level but, also at the
level of the group of workers.
Urinary manganese levels may be indicative of recent exposures, days to
weeks.
Tissue burden and serum concentrations of manganese do not correlate with
symptomatology,
and symptoms can occur and progress even after excess metal is cleared from
the tissues.
Therefore, serum, whole blood, and urine levels of manganese may be normal
in acute or chronic
intoxication and cannot be used to predict severity of disease or future
progression.
This is contrast with lead encephalopathy.
Among workers, kept away from their job on a temporary basis, and from
exposure to
manganese dioxide, a good correlation was observed between urinary and blood
levels
and the index of cumulative exposure, on an individual basis(Lucchini and
al.).
A correlation was also found between these tests and different
neurobehavioral tests.
Tanaka & Lieben however observed a correlation between the urinary excretion
and
the intensity of exposure, and Japanese authors suggested that manganese
excretion
higher than 40-50 micrograms/liter corresponds to a level of exposure where
lesions
can occur (Horiuchi & al.) .
3-Synopsis of Laboratory Surveillance :
Laboratory and diagnostic testing in manganese toxicity
____________________________________________________________________________
__
Laboratory or diagnostic test
Abnormal findings
____________________________________________________________________________
__
Urinary levels
>10 mg/L. (normal reference, range 0.5 to 9.8 mg/L; up to 50 mg/L. for
occupational exposure)
Whole blood levels
>19 mg/L. (normal reference, range 8.0-18.7 mg/L.)
Serum levels
>1.3 mg/L. (normal reference, range, 0.3-1.3 mg/L.
Electroencephalographic
Low-amplitude, weakened rhythms.
parameters.
Neuropsychiatric testing
Decreased memory, decreased reaction time, decreased motor coordination.
CT scan, magnetic resonance imaging Radiodense
accumulations of manganese in affected areas, abnormalities in globus
pallidus, caudate nucleus, putamen.
Positron emission tomography
Normal fluorodopa scan.
____________________________________________________________________________
__
Later,
"Ils sont fous ces quebecois"
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
http://www.digitalfire.com/education/toxicity/
Brian Molanphy on fri 19 dec 03
ron roy wrote in part:
'...Will you tell us where you learned that manganese is dangerous?
I got a phone call from a woman in California yesterday - urging me to
keep
posting on this subject.
She used to work with a Manganese glaze - used to scrape it off the rims =
-
which produced dust. She now has Parkinsons and tremors and restless =
legs
-
and is sure it came from working with Manganese. She is in her mid 60's =
so
it looks like her disability is not attributable to old age...'
ron, this question may not be directed to all of us, but i would like to
venture that many of us who began making ceramics in past 5-10 years =
heard
that manganese is dangerous on account of david shaner. -brian
Ron Roy on sun 21 dec 03
Hi Edouard,
So what you are saying is - the province (BC) funded the study - and part
of the study was done at provincial institutions - and you have no
questions to ask?
Well I have a few - perhaps you can direct me to the site where I can get
the information about how and when the testing was done and get the names
of the potters who took part.
When looking at data on toxicity I have learned - I am often looking at
only the tip if the iceberg.
I have also learned that not all toxicologists are equal.
The question about how much manganese was being used has nothing to do with
how much the potters could obtain but how much was in the clay and glazes
they are using. It has a profound effect on how much would be found.
Actually - a capitalist contractor would have the same chance of having the
latest equipment - it is an important factor in evaluating toxic levels.
You say - "The lawmakers in our specialty always base their decisions on
specialists teaching at our universities or working for government
agencies, these people are not paid by the industrialists.EB"
Do you actually think they have never made any mistakes or have had to toe
the line to keep their jobs. Would it not be more prudent to listen to
independent workers in the field as well?
RR
>"And maybe the work areas were extra ventilated because they knew they were
>going to be tested - and maybe the accumulated condenced manganese from the
>fuming which had accumulated over the years was not sampled.(RR)"
>
>A-I have no reason to doubt the sincerity, honesty and knowledge of the
>people who
>conducted this research. Most of the authors belonged to the Department of
>Health Care and Epidemiology of the University of British Columbia and one
>belonged to the Occupational Hygiene Program of the same university. This
>project was funded by the British Columbia Medical Services Foundation.
>As you see it was not funded by some industrialists or capitalist
>organizations.
>The workplaces and potters sampled had nothing to do with any type of
>ownership in the hands of investors.
>
>The ceramists sampled worked in 5 categories of workplaces:
>-professional studios,
>-recreation centres,
>-elementary schools,
>-secondary schools,
>-colleges.
>I do not think that any of these ceramists had any interest in
>over-ventilating
>their workplaces during the study, it was in their personal interest to
>participate
>in a project defined to establish their exposure to a myriad of chemicals in
>order to improve their working conditions.
>
>B-Now, as for the deposited manganese on different surfaces in workshops my
>answer is that what counts is the amount inhaled. (EB)
>
>"Maybe there was very little manganese being used in the glazes and
>clay.(RR)"
>
>They had the freedom to use the amounts of manganese they wanted to use.(EB)
>
>"Maybe the equipment used to measure the manganese was not state of the
>art.(RR)"
>
>I also doubt that very much, the chemical analyses were done by the
>University of British Columbia Occupational Hygiene Laboratory, not a
>capitalist contractor.EB
>
>"I say - don't be lulled into thinking it's safe because you like using
>manganese. It is a very serious toxin and you can't undo the results to
>your health.RR"
>
>Well, I know more about the toxicology of manganese than you do. You
>probably know
>more than me in ceramics technology but, we are talking toxicology in this
>post.EB.
>
>"If you want to believe that there are no problems with government limits
>that is up to you - but understand - governments guess low until the uproar
>is so loud they have to change em.RR"
>
>The lawmakers in our specialty always base their decisions on specialists
>teaching at our universities or working for government agencies, these
>people are not paid by the industrialists.EB
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 sun 21 dec 03
Hi Ron,
So what you are saying is - the province (BC) funded the study - and part
of the study was done at provincial institutions - and you have no
questions to ask?(RR)
I will send the file containing the article I am refering to in .pdf format.
This should settle the question.
Thanks to Taylor Hendrix from wacky Waco (hehehehe) who supplied
me with the article while I only had the abstract(EB)
Also, those you want it, let me know and I will send it(EB)
Do you actually think they have never made any mistakes or have had to toe
the line to keep their jobs. Would it not be more prudent to listen to
independent workers in the field as well?(RR)
All those working in universities and governmental agencies are rather
independant by nature, take me as an exemple. Quebec has maybe the most
stringent
laws and by-laws in the field of the environment and occupational health and
safety.
In the case of occupational health and safety I am the one who conducted the
pilot
projects so these laws could be passed while Rene Levesque was in power.
He never believed we could pass them but, we succeded in conducting these
projects in the industrial region of Sorel-Tracy with the help of the unions
because big business did not want to hear about them.(EB
Later.
"Ils sont fous ces quebecois"
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
http://www.digitalfire.com/education/toxicity/
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