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A'AiVTICV.;. ISSF.a RC i r f..\\.U>'NT REPORT SA 35
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Examination of Asbestos in Talca (Q64-1Q7)
tManuf ac ture _____ Various_________ _
Deparireen^_____ Analytical Research
Requested by
R. W. S c o tt
Customer _Oats Completed 8/17/72
. ABSTRACT
The Illinois Pollution Control Board lias adopted regulations restricting asbestos omission. In order to establish S-W compliance it was nece- : iry to daterminu the prononce or absence of fibrous asbestos in talcs used inJ Chicago production.
Microscopic and X-rny diffraction examination of tha four talcs used
in Chicago production indicates cliot 02 20 26 and 62 30 21, both Eatala,
nra clean rnlcnj tho formpr iu of finer and more uniform particle size.
1lie 62 20 21 (Nytnl) nnd 62 20'24 (Mtotron) talca are contaminated with
tremalLte which in n m in o ra i cluani.fi.cd as asbestos} the former contains
more tremollte.
PLAINTIFFS EXHIBIT
CAM-372
Analyst
Y&-
Dr. Frank H. Chung/ac
cc - HES JOT FCC KRB
/
t/
" Richard W. Scott, Director Analytical Research Department Sherwin-Williams Research Center
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SW GOODHUE 000004
COMPANY CONFIDENTIAL . ADP-8435 -3-
DISCUSSIOM
Talc and asbestos are often Intermixed in the same ore deposits.
Both are different crystal forms of hydrated magnesium silicate minerals.
There are two classes of asbestos, chrysotile and amphibole. Moat of the
materials commercially known as 'asbestos' are chrysotile; all varieties
other than chrysotile are called amphibole. The fundamental differences
between them are:
t
Chrysotile
Amphibole
Very small cross-section Tabular Soft and flexible
Large crops-section Flat narrow sheets ` Hard and brittle
Tremollte is an amphibole present in two of the tales, Nytal and Mistron, used in Chicago production. It Is noteworthy that no treoolite waa observed in the two Emtela by either microscopic or X-ray diffraction methods.
The asbestos regulations are concerned with alr-bofne asbestos, which might cause lung cancer or skin tumors, but not the asbestos in the paint as auch. Normal weathering of a paint film should not yield enough aebestos to be of concern. Therefore, our attentions should be directed to the factory operations of introducing the talcs into the reactors.
SW GOODHUE 000005