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fiber vs brick (long) (f

updated mon 30 jun 97

 

Monona Rossol on sat 7 jun 97




> Monona, I feel you owe Jeff Lawrence and the rest of the list an apology.
> The following statement is not necessary and uncalled for in an open forum.

<<>>

Go back and read what *he* said. I fought fire with fire. And all I did
then was repeat in different words exactly what I said previously that he
obviously didn't read.

> As for attacks on me, well...I'm a big boy..I'll live.<

And so will Jeff.

> You questioned my
> trust worthyness because I'm a "potter/burner builder who has a vested
> interest in selling RCF". Yea, so? I could be wrong, but aren't you paid by
> lawyers to be an expert witness in lawsuits against product manufacturers? <

30 years ago I gave seminars on ceramic hazards in graduate school. It
paid me nothing. My opinions were the same then as they are now on acid frit
tests, labeling and toxicity of glaze chemicals. But at this time, I thought
fiber was great. Then the animal data started coming in and my opinion
changed. I didn't get paid for my RCF opinion either. And all this time I
did *no* expert witness on this subject.

Now I am getting cases in droves--not because I am paid to hold these
opinions, but because my opinions were already published and well-known. The
fact that I am now making money by repeating what I've said all along is
amazing to me.


> I agree, there are two hazards to RCF. But, what literature do you use to
> support your claim that the fiber itself is the most dangerous? <

I already quoted EPA's short summary of the animal data. I looked at all
the data they presented in the Federal Register on May 14, 1993 and agree
that it is both a respiratory hazard and a carcinogen.

> "OSHA DOES REGULATE
> cristobalite". "OSHA HAS PROPOSED REGULATING" fiber. <

Your argument is political, not based on the hazards of the fiber. OSHA
believes it should be regulated. So do I. This is a tough climate to
get regulations through.


> I do not know for a fact that OSHA has proposed regulating fiber. They may
> have or they may not have, but they have recommended standards and
> manufacturers of RCF have voluntarily agreed to accept a standard of 1
> fiber/cc. <

The proposed regulation was published in the Federal Register on June 2,
1992.


> The reason there is no regulation on fiber itself is because of
> the findings of IARC (International Agency for Research on Cancer). <


**You just make up stuff when it suits you!** OSHA didn't even consider
carcinogenicity when they proposed a 1 fiber/cc PEL. Let me quote from the
proposed rule, 57 FR 26202 at the conclusion of many pages of review of
studies. They summarize:


"An ongoing morbidity study of RCF workers has demonstrated an increase in
the prevalence of respiratory symptoms, pluritic chest pain, and pleural
plaques and a decrease in pulmonary function that was significantly
associated with duration of exposures. In each of these studies, workers
were exposed to fiber concentration in the range of OSHA's proposed PEL." [1
fiber/cc]
.......

"OSHA preliminarily concludes that this limit will substantially reduce
the significant risk of nonmalignant respiratory disease that exists in the
absence of a limit for workers in all sectors."

"OSHA has presented the evidence of possible carcinogenicity of fibrous
glass, including refractory ceramic fibers. There is also a substantial body
of ongoing research. At this time OSHA believes it is premature for the
Agency to reach a final decision on an exposure limit based on
carcinogenicity."

So you see all your explanation about the different levels of IARC is a waste
of time.

It is not OSHA but EPA that is proposing to regulate RCF on the basis of
carcinogenicity. EPA wants to keep exposure to the "lowest achievable level"
as a carcinogen. And so do I. And I repeat: If you have about 80 % of the
fiber and 20 % of cristobalite, the fiber itself is with greatest hazard.


>The IARC has five categories regarding the carcinogenicity of substances.
>They are:

> Category 1: Sufficient evidence of human carcinogenicity
> Category 2A: Probably carcinogenicity to humans
> Category 2B: Possible carcinogenicity to humans
> Category 3: Not classified as to human carcinogenicity
> Category 4: Probably not carcinogenic to humans

> Cristobalite is classified as 2A by the IARC
> Fiber is classified as 2B by the IARC
> Cristobalite is regulated by OSHA
> Fiber is not regulated by OSHA

Lets look at the whole definition of IARC 2B: Possibly Carcinogenic to
Humans: limited evidence in humans in the absence of sufficient evidence in
experimental animals.

RCF is also classified 2B by NTP. Their definition is: Sufficient evidence
of carcinogenicity from studies in experimental animals.

RCF can't get the top classifications until the human data is in. And the
asbestos-like cancers are not quite due yet. As I mentioned, 12.5 % of the
workers exposed more than 20 years ago already have pleural plaque.
Although the number of workers being studied is small, a few more years and
we should expect to see a couple mesotheliomas.


> The International Agency for Research on Cancer (IARC) believes cristobalite
> is more dangerous than fiber.<

It doesn't. It only reviews and forms an opinion on the *available* data.
The human data is limited at this time.

> OSHA (Occupational Health and Safety Administration) believes
> cristobalite is more dangerous than fiber. <

They only want to regulate on the basis of non-malignant hazards until more
data is available.

>I believe cristobaltite is more dangerous than fiber. <
Monona doesn't.<

Especially when there is roughly 4 times more fiber than cristobalite in the
dust. Geez.

> Let us avoid the confrontation that happened over the salt emission issue. <

You exaggerate. That was a very interesting exchange and I enjoyed it muchly.

> Carborundum produces a good pamphlet on working with fiber. They can be
> reached at 800. 322-2293. Request Form #C-1321-K. <

The fibers division changed its name from Carborundum to Unifrax
Corporation some time ago. I sent your Clay Times article off to the
President, William Kelly, who subscribes to my newsletter. I thought he
might want to comment on it. It is very misleading.


Monona Rossol, industrial hygienist
Arts, Crafts and Theater Safety
181 Thompson St., # 23
New York, NY 10012-2586 212/777-0062

http://www.caseweb.com/acts/