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March Id, 1976 To: Dr. C. H. Costello From: J. P. Simko, Jr. Subject: Analytical Data on Talc Samples 1972-Present (i'J > S i n c e late 1972 w h e n - t h e p o s s i b i l i t y of a s b e s t o s in talc -was first raised, RfD Analytical has been engaged in re-analysing U.S. t a l c raw m a t e r i a l a n d - f i n i s h e d p r oducts for a s b e s t o s _m i n e r a l s by the most sophisticated methodology,available at that time. A n a l y s e s w e r e m a d e on a spot *c h e c k b a s i s : T e c h n i q u e s u s e d m house are x-ray .diffraction followed by o p t i c a l a n d scanning e l e c t r o n m i c r o s c o p y , if n e c e s s a r y . X-ray is the b a s i c screc-iun tool a n d e x a m i n a t i o n by m i c r o s c o p y is m a d e w h e n p o s i t i v e v - s p o n s e s occur. A d d i t i o n a l tests on r a n d o m samples w e r e m a d e by trailsm i s s i o n e l e c t r o n m i c r o s c o p y and s e l e c t e d a rea e l e c t r o n di ti.raction by an outside consulting firm. F o r t y - t w o sam p l e s (from dO r a w m a t e r i a l s a n d f r o m 1/ f i nished p r o d u c t s ] , c o v e r i n g the p e r i o d 1971 to the present., h ave b e e n examined b^ these various techniques.. Asbestos minerals wcre_not d e t e c t e d in any of these w i t h . t h e ' e x c e p t i o n o f . t r ace amounts -in 3 samnles- f rom 19''!-:. T h e s e lev e l s are c o n s i d e r e d yenei*ll>_ -ulu. the normal background levels encountered wnen this microscopic m e t h o d o l o g y is' employed, It is b e l i e v e d that t h ese trace a m o u n t s are d u e to' l a b o r a t o r y c o n t a m i n a t i o n . A 'detailed tabula t i o n is attached. JPS/ed tt PLAINTIFFS EXHIBIT WCD-42 Ko. of Samples Examined for Asbestos Minerals 1972-76 Method, TEM-SAED ;. Sample dates (yrs.) Raw Talc *5 ` . 1971-72 Cashmere Bououet **7 1972-76 X-ray plus microscopy (optical - SEMj- Sample dates (yrs.) 12 1971-76 11 1972-76 DTA Sample dates (yrs.J 6 1972 1 1972 sample 19 71 raw talc contained 10-100 ppm. chrysotile *1 sample 19 73 raw talc contained 1-10 rpm, chrysotile These level.,, A present po^sib background von tan.nation **1 sample 197? Cashmere Bouquet taic contained < 5 ppm. chrysctiih No araphlbole detected in. any of these. JPS/ed 3-12-76 *