Date: Thu, 9 Sep 2004 13:41:20 EDT
Reply-To: ACTSNYC**At_Symbol_Here**CS.COM
Sender: DCHAS-L Discussion List <DCHAS-L**At_Symbol_Here**LIST.UVM.EDU>
From: ACTSNYC**At_Symbol_Here**CS.COM
Subject: Re: Managing Chemicals with stench characteristics
Comments: To: mrsafetyman**At_Symbol_Here**
MR:  I'll answer in the body of your e-mail:

In a message dated 9/8/04 9:09:50 PM Eastern Daylight Time,
mrsafetyman**At_Symbol_Here** writes:
> Wow, thanks for the input. The product does have a rather low health hazard

MR:  There are two types of Great Stuff Products.  The first type is the
Great Stuff which says on the can it is for "household use."  The other spray can
products are  Great Stuff Gaps and Cracks, Great Stuff Window Seal, etc.
And all of these are available at good hardware outlets that contractors use.

Great Stuff Gaps and Cracks contains between 5 and 30% (this alone is a
worry) a polymethylene polyphenyl isocyanate CAS # 9016-87-9, that contains 40-50%
4,4'methylene bisphenyl isocyanate CAS#  101-68-8 (MDI).

This means that somewhere between 2% and 15% of the product is MDI with a
TLV-TWA of 0.005 ppm, Recommendations for air-supplied respirators are on the
MSDS because there is no cartridge approved for it without change out schedules
and air monitoring.

I searched and searched the Dow site and it apparently does not provide the
MSDS for the household variety.  But according to the National Institutes of
Health National Library of Medicine's Household Product Database, the prepolymer
is the primary ingredient and only 0.2-0.05% is in the form of MDI.  But
other countries recognize that the prepolymer is just as toxic as MDI, it just has
a lower vapor pressure so exposure should be lower.   In England, for
example, the occupational exposure to this product would be regulated by the number
of isocyanate units on the compound, not the compound to which the units are

In the US, if you change the structure of the compound, it is now unregulated
and can be labeled without warnings or even "nontoxic" if you choose.  This
is nuts.  But it can explain why a product that contains reactive isocyanate
structures has a low toxicity rating.

 and it is used by three labs I know of to seal bottles as well as many
contractors. I
> have not heard of an incident yet until now.

MR:  You won't.  Most people use the stuff for a while with no difficulties.
It is the people who become sensitized whose lives are ruined or who die.
Read about the isocyanates.  They are powerful sensitizers and irritants.  Some
cause cancer, so the effects will not be seen immediately.

>  contacted Dow and they advised that the product is safe if used
> correctly.

MR:  If you get your hazard data from the people selling the product, then I
have a car I want to talk to you about.

They have not had any recent litigation as of yet mentioning your incidents.

MR:  The workers' comp cases involve the employer, not Dow. And do you really
think Dow would tell you about any lawsuits pending or settled?

Why don't you provide me your snail mail address and I'll send you a long
data sheet on the urethanes which mentions some of the incidents of which I am
personally aware as a union rep and expert witness.

> direct me to actual other data or events that are documented since
> this is very enlightening to me. I inspect many facilities as a code
> enforcement officer and that is how I saw the processes of corking during a fire
> inspection. If i had some hard data, this would enable me to approach those i
> know that perform this work.
> Thanks for your assistance and input.

MR:   This is not a mystery--it is a well known problem.  How else could the
ACGIH set a 0.005 ppm TLV-TWA for MDI?   They have to have a PILE of data to
set a low TLV or the affected industries will sue them for restriction of trade.

Ah, that's the answer to your questions.  Get a copy of the ACGIH
Documentation of TLVs for MDI.  That will put it all in perspective for you better than
my data.  All the data and references are there.

Monona Rossol, M.S., M.F.A.,
industrial hygienist
Arts, Crafts & Theater Safety, Inc.
Safety Officer,
United Scenic Artist's, Local 829
International Alliance of Theatrical Stage Employes (IATSE)
181 Thompson St., #23
New York NY 10012-2586     212/777-0062

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