Rafael Molina on wed 28 jul 99
-------------------
Clayarters:
Can anyone on the list enlighten me about the specific hazard of vapors from=
hot
paraffin wax? What is the specific material in the vapor, toxicity, etc,...
TIA.
Rafael
Tom Buck on fri 30 jul 99
Rafael M:
I hope Edouard B (a medical doctor) treats us to his rundown on
this hazard. But from my purely chemical viewpoint, this stuff presents a
real hazard to our lungs.
The paraffin wax, aka microcrystalline petroleum wax, is
characterized in most chem books as being -(CH2)-n where n=1000 (lowest)
to 10,000 (expected highest chain length) units.
When this polymer is heated there is every likelihood that the
chain will break here and there, and oxo compounds will be formed, some
low voltility some high volatility (low could be acetone, high could be a
glycol with a big chain length, eg, radiator/engine coolant). Some oxo
compounds our bodies can handle but some a strong poisons.
I decided some years back to stop using paraffin wax resist; I
felt the risks were unwarranted given today's excellent vapor-free (when
applying) emulsion wax resists.
Tom Buck ) tel: 905-389-2339
(westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street,
Hamilton ON L8T 3E1 Canada
David Hendley on sun 1 aug 99
I am not trying to be smart-ass here, but I wonder:
Why is hot wax in the pottery shop, used with care and
ventilation, considered a risky hazard, but a dozen candles
burning in a closed-up living room considered a desirable,
relaxing, and romantic atmosphere?
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com
At 10:38 AM 7/30/99 EDT, you wrote:
>----------------------------Original message----------------------------
>Rafael M:
> I hope Edouard B (a medical doctor) treats us to his rundown on
>this hazard. But from my purely chemical viewpoint, this stuff presents a
>real hazard to our lungs.
> The paraffin wax, aka microcrystalline petroleum wax, is
>characterized in most chem books as being -(CH2)-n where n=1000 (lowest)
>to 10,000 (expected highest chain length) units.
> When this polymer is heated there is every likelihood that the
>chain will break here and there, and oxo compounds will be formed, some
>low voltility some high volatility (low could be acetone, high could be a
>glycol with a big chain length, eg, radiator/engine coolant). Some oxo
>compounds our bodies can handle but some a strong poisons.
> I decided some years back to stop using paraffin wax resist; I
>felt the risks were unwarranted given today's excellent vapor-free (when
>applying) emulsion wax resists.
>
>Tom Buck ) tel: 905-389-2339
>(westend Lake Ontario, province of Ontario, Canada).
>mailing address: 373 East 43rd Street,
> Hamilton ON L8T 3E1 Canada
>
>--------------------------------------------------------------
>
>All waxes, paraffin, beeswax, microcrystalline, etc., will dissociate with
>heat into many different chemicals, many of which are very toxic. This
>process begins at the point at which they melt. However, at the bare minimum
>melting point, the amounts to toxic chemicals are not significant enough to
>worry about. For example, paraffin heated in a double boiler (so that the
>temperature can't get above 212 o F) produces no significant emissions.
>
>
>The higher the temperature above melting, the more toxic chemicals are
>released. The two most commonly seen emissions are acrolein and paraffin
>fume. But formaldehyde, many other aldehydes, and a host of small amounts of
>many other chemicals are released as well.
>
>
>Acrolein in particular is nasty. It has the same workplace air quality
>standard (TLV = 0.1 ppm) as phosgene, which is chemical warfare gas!
>There is no respirator cartridge approved for acrolein and so ventilation is
>your only answer.
>
>
>Paraffin fume is less toxic (TLV = 5 mg/m3) but its presence signifies that
>many other chemicals are also present. It is also the major cause of the
>explosive flash fires that occur around wax pots.
>
>
>I have a data sheet called "All About Wax" that goes into more detail about
>wax hazards and candle emissions. I will send it to Clayarters who send me a
>self addressed stamped envelop.
>
>Monona Rossol
>ACTS
>181 Thompson St., # 23
>New York NY 10012-2586 75054.2542@compuserve.com
>
Edouard Bastarache on sun 1 aug 99
------------------
Hello Tom,
there is not much said in medical textbooks about this problem.
Among those i have at hand only =22Dangerous Properties of Industrial
Materials=22
says the following:
=22The semi-refined, fully refined and the crude paraffins are experimental
tumorigens by the implant route. Many paraffin waxes contain carcinogens.
Used as a sealant, chewing gum base and to produce candles=22
In the processing of shale oil, the stage at which human contact was first
made was
during the removal of paraffin from the filter presses used to separate it
from
the shale oil. Contact occurred again when packing paraffin into hydraulic
presses and in removing the hardened wax to sweating sheds where the last
oil
was removed by steam heat. The first report of a health hazard was in 1876,
when skin cancers were reported.
In 1955, the results of a study were published on a group of workers
engaged in manufacturing paraffin wax. An association of scrotal cancer was
shown with work on the presses of 10 years or more.
A study in 3 Texas oil refineries showed that stomach cancer risk was
elevated among
maintenance workers and workers exposed to lubricating oils and paraffin wax
processing (second step refining).
One case of contact dermatitis was described in 1991:
=22All the candles in the cathedral were made from a 9:1 mixtures of =
paraffin
and beeswax. Wax bleaching with benzoyl-peroxide and shaping of candles were
performed for several hours at maximum temperatures around 90 degrees C.
This temperature was too low to evaporate the benzoyl-peroxide from the
candles during their manufacture=22.
One survey of exposure of workers to wax fume did not show any hazard at
Cornell
University:
=22Based on these results it was concluded that a health hazard did not =
exist
from employee exposure to paraffin wax fumes or petroleum solvents.
Now here is what russian authors conclude in1973:
=22The authors conclude that wax is safe and hygienic and recommend its
use for packaging and wrapping food products. (Russian)=22
Monona Rossol came up with some excellent information yesterday but i wish
i knew more about the by-products of heating waxes, supposing potters used
different ones.
The study conducted at Cornell University gives us a good idea that exposure
to
wax fumes is not much hazardous, even if unleasant at times.
Later,
Edouard Bastarache
edouardb=40sorel-tracy.qc.ca
http://www.sorel-tracy.qc.ca/=7Eedouardb/
-----Message d'origine-----
De : Tom Buck =3CTom.Buck=40hwcn.org=3E
=C0 : CLAYART=40LSV.UKY.EDU =3CCLAYART=40LSV.UKY.EDU=3E
Date : 30 juillet, 1999 10:33
Objet : Re: Hot Paraffin Wax Vapor Hazard?
----------------------------Original message----------------------------
Rafael M:
I hope Edouard B (a medical doctor) treats us to his rundown on
this hazard. But from my purely chemical viewpoint, this stuff presents a
real hazard to our lungs.
The paraffin wax, aka microcrystalline petroleum wax, is
characterized in most chem books as being -(CH2)-n where n=3D1000 (lowest)
to 10,000 (expected highest chain length) units.
When this polymer is heated there is every likelihood that the
chain will break here and there, and oxo compounds will be formed, some
low voltility some high volatility (low could be acetone, high could be a
glycol with a big chain length, eg, radiator/engine coolant). Some oxo
compounds our bodies can handle but some a strong poisons.
I decided some years back to stop using paraffin wax resist=3B I
felt the risks were unwarranted given today's excellent vapor-free (when
applying) emulsion wax resists.
Tom Buck =3CTom.Buck=40hwcn.org=3E) tel: 905-389-2339
(westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street,
Hamilton ON L8T 3E1 Canada
Gavin Stairs on tue 3 aug 99
At 11:19 AM 01/08/99 , David Hendley wrote:
>----------------------------Original message----------------------------
>I am not trying to be smart-ass here, but I wonder:
>Why is hot wax in the pottery shop, used with care and
>ventilation, considered a risky hazard, but a dozen candles
>burning in a closed-up living room considered a desirable,
>relaxing, and romantic atmosphere?
Good point, David. I think the answer is partly that what we accept is not
necessarily completely without risk. The other part is that we are
continually talking about marginal risks here on clayart. Not marginal is
the sense of insignificant, but in the sense of difficult to quantify, and
more likely to complicate and contribute to illness than to kill outright.
Our distant ancestors lived in smokey shelters heated by open fires. They
probably inhaled more combustion byproducts than we do today, even with
kilns, candles and other hazards. Enough of them survived to produce all
of us, which is potent evidence for the marginality of it all. However,
the birth rate was much higher, to offset all those still births and infant
deaths. And tuberculosis and other lung disease was not unknown. In the
case of candles and hot wax, I suspect that much of the risk is similar to
the risks of petroleum solvents, which have been recently shown to be
correlated with pregnancy complications and infant morbidity of various
kinds. So I would hazard that pregnant women would be well advised NOT to
enjoy many candles at the dinner table. Also, to lay off the wine. As for
the old potters around who are well past reproduction age, it probably
matters much less.
Much of what we take for granted is not good for us. Since we don't drop
dead on the spot, we tend to accept it. Smoking is one of those habits
which is now becoming unacceptable, because scientists have spent much
effort in documenting the resulting delayed effects, and have found them to
be unacceptable. Individuals may still decide differently, but they can no
longer claim ignorance. The effects of hot wax, burning nylon, etc. are
similar. You may decide that in your case they are acceptable risks, but
that doesn't alter the fact that they are risks.
The same arguments apply to glaze safety. No given potter on this list is
likely to die from the use of lead glazes, or improper use of other toxic
colorants and modifiers. But certainly many potters have died from lead
poisoning over the years, and not a few users of lead glazed
earthenware. Those two facts have lead people over the years to discount
the risk, since it was not a clear risk to life for any individual, and the
overall results were not apparent. If someone went mad, or became ill,
there was no smoking gun about. Few, if any, people had the understanding
to pick up the lead glazed pottery, the leaded glass, the lead pewter and
exclaim, "Here is the instrument of this death!"
We are becoming more aware of these things now. It often may seem that
everything we touch has just in the instant turned into a deadly
poison. That is obviously not the case. However, we are becoming aware
that a 0.1% risk of death means that 1 person in a thousand, on average,
will die of that risk. Or, in grand terms, 300,000 Americans might die of
that risk, if exposed to it en masse. The likelihood that any of these
might be yourself, or even one of your immediate family, might seem
acceptably small. I guess those numbers are not too far from the current
annual risk of traffic death. We seem to accept those odds. We seem less
able to accept a smaller death rate from drinking orange juice from a lead
glazed pitcher.
I have already said on this list that we should not be panicked by these
facts. Rather we should accept that our conceptual framework of risk is
being modified by new knowledge of the effects of our practices, and try to
properly weigh the new knowledge in order to understand what we can accept,
and what we cannot accept. The preponderance of views on this list seem to
be that the use of lead glazes in the studio is not justified, that certain
other toxics are also not justified, or should be monitored. We are
beginning to understand the risks involved in volatile solvents, perhaps
including hot wax, and also including petroleum fuels as used in a
reduction kiln, and even bake-out fumes from electric kilns firing
fibre-clay, ball clays and other organics. We speak more of venting.
Specific to wax, Edouard Bastarache just posted that there is not much in
the scientific literature about the risks, and some of it is mildly
contradictory. It is probably true that what risk there is linked to
temperature. So, if you use a hot wax dip, you should probably keep the
temperature well regulated and low. You candles are probably not efficient
emitters of volatiles, although I have noted that candles sometimes sweat
in use. I think we can take it that no study has yet been made of the risk
to a pregnant mother or her fetus of leaning toward a dinner table candle
while breathing deeply.
There are many topics in this line that need to de discussed, and many
risks to be weighed, including environmental risks. I think that our duty
as potters is to minimize the risks we expose other to, by good practice in
all of our tasks. It is hardly ever possible to remove a risk
entirely. It is practically always possible to reduce it to insignificance.
As you know, David, this note is not directed at you particularly. You
note was a convenient excuse to ponder these things once more.
Gavin
Hank Ray on wed 4 aug 99
Hey,,,,,,
I use paraffin wax 50% with paraffin oil 50% I use this mixture almost
exclusively for brushing on the wax... i do sometimes dip my pots in it.....
it works great for me...
that said.... if it smokes your skillet is turned up to hot... In fact, i
can promise you that if you would like to come to the City Art Center i will
demonstrate that you won't even smell the skillet with the wax in it...
if the skillet smokes or fumes i turn it down.... i find that the skillet
on warm ( the lowest setting) seems to work good...
Pete in OKC
www.cityartscenter.com
amy parker on wed 4 aug 99
At 11:19 AM 8/1/99 EDT, you wrote:
>----------------------------Original message----------------------------
>I am not trying to be smart-ass here, but I wonder:
>Why is hot wax in the pottery shop, used with care and
>ventilation, considered a risky hazard, but a dozen candles
>burning in a closed-up living room considered a desirable,
>relaxing, and romantic atmosphere?
>
>David Hendley
David - I suspect that the amount of wax vapor is the consideration. A
dozen candles have a dozen small melted puddles, with an active flame
directed up the wicks. An electric frying pan of paraffin has a huge
surface area, with no wick and no active flame to channel the vapors, and
can burst into one huge flaming surface. I'm no scientist, but I've made
enough candles over the years to have set a couple of wax containers alight!
When it hits the "flash point", you have a huge mess!
Amy in TooHotlanta, where I can't get up the nerve to think about turning on
the kiln & adding more heat to the world!
amy parker Lithonia, GA
amyp@sd-software.com
Kathi LeSueur on thu 5 aug 99
In a message dated 8/2/99 12:39:10 AM, hendley@tyler.net writes:
<< I am not trying to be smart-ass here, but I wonder:
Why is hot wax in the pottery shop, used with care and
ventilation, considered a risky hazard, but a dozen candles
burning in a closed-up living room considered a desirable,
relaxing, and romantic atmosphere?
>>
As always, David, you go to the heart of the matter. I chuckled when I read
this one. It makes about as much logic as the vegetarian who won't eat meat
because he doesn't want animals killed but wears leather sandals and jackets.
Kathi LeSueur
millie carpenter on fri 6 aug 99
what is parafin oil, and where does one get it?
millie on the chesapeake bay-with drought conditions and a government
imposed burn ban and water rationing.
Hank Ray wrote:
> ----------------------------Original message----------------------------
> Hey,,,,,,
>
> I use paraffin wax 50% with paraffin oil 50% I use this mixture almost
> exclusively for brushing on the wax... i do sometimes dip my pots in it.....
> it works great for me...
>
> that said.... if it smokes your skillet is turned up to hot... In fact, i
> can promise you that if you would like to come to the City Art Center i will
> demonstrate that you won't even smell the skillet with the wax in it...
>
> if the skillet smokes or fumes i turn it down.... i find that the skillet
> on warm ( the lowest setting) seems to work good...
>
> Pete in OKC
> www.cityartscenter.com
Hank Ray on sun 8 aug 99
Hello all....
I get paraffin oil in any large hardware, craft or such type store... you
find it in the section where they sell the lamp oil..... but you don't want
lamp oil... you want the bottle right next to it that says... 100% paraffin
oil.....
Pete over and out...
In a message dated 8/6/99 3:27:36 PM !!!First Boot!!!, millie@bcpl.net writes:
> what is parafin oil, and where does one get it?
>
> millie on the chesapeake bay-with drought conditions and a government
> imposed burn ban and water rationing.
>
> Hank Ray wrote:
>
> > ----------------------------Original message----------------------------
> > Hey,,,,,,
> >
> > I use paraffin wax 50% with paraffin oil 50% I use this mixture
> almost
> > exclusively for brushing on the wax... i do sometimes dip my pots in
it....
> .
> > it works great for me...
> >
> > that said.... if it smokes your skillet is turned up to hot... In
fact,
> i
> > can promise you that if you would like to come to the City Art Center i
> will
> > demonstrate that you won't even smell the skillet with the wax in it...
> >
> > if the skillet smokes or fumes i turn it down.... i find that the
> skillet
> > on warm ( the lowest setting) seems to work good...
> >
> > Pete in OKC
> > www.cityartscenter.com
>
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