Document 6RV2ae03V8g6Gp5pDvzvRrYQm

FILE NAME: Azrock-Domco (AZD) DATE: 1969 May 26 DOC#: AZD003 DOCUMENT DESCRIPTION: Asbestos Toxicology Report - Company Newsletter # /// ' lY/fi . "Vo: C r o u p I F i e l d S a l e s F or c e May 2 6 . l<i6'J ASBESTOS TOXICOLOGY REPORT A ttached Is che roost r e c e n t T oxicology R eport on A sbestos os issued by Union C a rb id e . Thu o n l y m a j o r c h a n g e i s Che n o t a t i o n r e g a r d i n g t h e c h a n g e In c i n c s h o l d l i m i t v a l u e (TLV) f r om 5 m i l l i o n j i a r t i c l c s p e r c u b i c Coot o f a i r (ropcf) to e s t a b l i s hed b y j t h e _D e p a r t m e n t o f L a b o r u n d e r t h e Walsh-Healy Act. This environmental safety r e s tr ic tio n applies to concerns supplying m aterials under government co n tract or involving p u b lic tLinds. 11 Is a lm o s t c e r t a i n t h a t t h i s s t a n d a r d w i l l be adopted by t h e ACClH c o n l e r c . u c e f o r a i l i n d u s t r y . T h e s e iovoL:,- o f a s h e s cos, d u s t c o n c e n t r a t i o n c a n b e r e a c h e d by p r o p e r c a r e .ind e q u i p m e n t . The use of C aL id rla A sbestos p r o p r i e t a r y p e l l e t i z e d produces o t l l ninl.e e v e r y o n e ' s j o b c a s t e r ! USY/ds Attachment M S f J i cJ jC T U N I O N C A D m o t C O R P O R A T I O N C H E M I C A L S A N O P L A S T IC 'S 27(1 P A R K A V E N U E . N Y . N t,' ASBESTOS TOXICOLOGY REPORT I t ha s been known f o r y e a r s Chat some p e r s o n s w o r k i n g i n a s b e s t o s production were prone to develop a disab lin g lung d ise a se . In time, this c o n d i t i o n became known as a s b e s t o s ! and was r e l a t e d to e x p o su r e to high c o n c e n t r a ti o n s of a s b e s to s d u s t . U ith f u r t h e r e x p e r i e n c e , i t was found th at men c o u l d work w i t h a s b e s t o s w i t h o u t d e v e l o p m e n t o f lu ng d i s e a s e I f d u s t concentrations were kept below a c e rta in le v e l. Ic has been generally accepted chat a worker w ill not develop ssbestosls i f he i s exposed t o no more chan j m i l l ion p a r c i c l e s p e r c u b i c f o o t of s i r , e v e n i f t h i s e x p o s u r e c o n t i n u e s Cor Il l s e n t i r e w o r k i n g l i f e t i m e . A l t h o u g h no c a s e s o f a s b e s t o s i s a r e known to have o c c u r r e d when e x p o s u r e s have been m a i n t a i n e d a t o r b e l o w t h i s l e v e l , t h e ACGIH ( w h i c h s e t s t h e t h r e s h o l d l i m i t v a l u e (TLV) i n t h e U. S . A . ) h a s i n d i c a t e d t h e y I n t e n d co l o w e r t h e TLV f o r asbestos to 2 m illio n p a rtic le s per cubic foot in an e f f o r t to increase the s a t e t y f a c t o r i n c o r p o r a t e d i n t h e l i m i t . The U. S . D e p a r t m e n t o f La bo r has a l r e a d y i s s u e d a r e g u l a t i o n u n d e r t h e W e l s h - H e a l y A c t p l a t i n g t h e TLV f o r a s b e s t o s a t 2 m i l l i o n p a r t i c l e s p e r cu b ic f o o t f o r p u b li c c o n t r a c t s In which they have ju ris d ic tio n . This concentration of dust is generally not visible in th e a v e ra g e work a r e a u n le s s a beam of l i g h t c a u s i n g a T y n d a l l e f f e c t is p re s e u c . U sually the d u s t c o n c e n t r a ti o n must be from 8-10 m i l l i o n p a r t i c l e s p e r c u b i c f o o t (MPPCF) b e f o r e I t s p r e s e n c e i s v i s i b l e i n a v e r a g e l i g h t i n g cond i c i o n s . S e v e r a l y e a r s a g o . i t was r e p o r t e d t h a t t h e r e was an i n c r e a s e in che incidence of cancerous tumors, especially of the lung, associated with asbestosisR c c o u t l y (.here have b e e n r e p o r t s o f some c a n c e r s o c c u r r i n g i n i n d i v i d u a l s e x p o s e d t o a s b e s t o s d u s t , b u t who h a v e n o t d e v e l o p e d c l i n i c a l a s b e s c o s i s . I t exposures sig n ific a n tly exceeding the Threshold Limit Value. A t y p e o f c a n c e r named m e s o t h e l i o m a Has b e en n o t e d co be a s s o c i a t e d with a s b e s to s exposure in r e c e n t y e a r s . These tumors, w h ile r a t h e r tew in n u mb e r t o d a t e , may o c c u r i n i n d i v i d u a l s w i t h h i s t o r i e s o f o n l y s l L g l i t e x p o s u r e s , and t h a t a s much as tw ent y to f o r t y y e a r s e a r l i e r . T h e r e is considerable evidence th a t c ro c ld o lite is most frequently asso ciate d with m e s o t h e l i o m a s . From t h e d a t a a v a i l a b l e i c a p p e a r s t h a t che TLV o f '> MPPCF may n o t be low e n o u g h t o p r o t e c t a g a i n s t m e s o t h e l i o m a . R e s e a r c h on che p r o b l em continues. I IhJION C A I i m i )L: l i O H f n n A M O N Cl 18-MICALS A N f l I `I Ail [ I CC P / H I 'AIIK A v r P J U F . N 'i .M i KU]1/ > C ontrol of a s b e s to s d u st exposure Is th e r e fo re n e c e ss a ry . The control methods ore the standard ones applicable to a v a rie ty of dusty operations. They include closed flow systems, wet processes where p o s s i b l e , and adequate exhaust v en tilatio n where openings in the system are necessary. _Pelict'iiing is rjomotimes used to improve th e h a n d lin g c h a r a c t e r i s t i c s o f o th e r w ise d u s t y m a t e r i a l s . Where s a t i s f a c t o r y c o n t a i n m e n t t o s t a y w i t h i n t h e T h r e s h o l d L i m i t Value is im p ra c tic a l o r im possible, e f f i c i e n t and r e l i a b l e r e s p i r a t o r s are a v ailab le for the p ro tectio n of the employee. A program of environmental mouLtoring is highly d e sira b le to determine th at Threshold Limit Values are not being exceeded, i n manufacturing i n d u s t r i e s i t would be d e s i r a b l e to know th e d u s t c o n c e n t r a t i o n s where the a s b e s t o s i s dumped from bags in to the p ro c e s s. C oncentra tions should a ls o be determined where dusting occurs i n f i n i s h i n g p r o d u c t s . W h i l e i n i t i a l d u s t d e t e r m i n a t i o n s s h o u l d be made a t frequent in te rv a ls , once the level has been estab lish ed as s a tis f c to ry , the f r e q u e n c y may be e x t e n d e d t o o c c a s i o n a l t e a t a t o a a s u r e c o n t i n u a t i o n o f a satisfactory condition. ' * Pre-employment and p erio d ic physicaL examination o f workers are d e s ira b le . These should include chest'X -rays to insure th s t the worker has no c h e s t cond i t Ion" p r i o r ~ t b ' u o r k ~ w i t l i ' a s b s t o s ' a n d t o d e t e r m i n e t h a t no lung changes are r e s u l t i n g from work w ith a sb e s to s. '-- I t i s b e l i e v e d t h a t t h e a d d i t i o n o f a s b e s t o s a t Che p r o p o s e d l e v e l s d u r i n g th e m a n u f a c tu r e o f p ro d u c t s would be h a rm le s s to th e consumer. T o ta l d u s tin g would have to be w ell in excess of any le v e ls a c c e p ta b le to the consumer for the asbestos concentrations to approach the Threshold Limit Value. " In conclusion, while asbestos Value 'is p o te n tia lly hsrmfuL, as are it (s as readily c o n tro lled as o th er with appropriate precautions. dust many such i n e x c e s s o f t h e T h r e s h o l d Litnlc other dusts encountered in industry, d u s ts and i t can be used safely 3/8/69 I n d u s t r i a l M e d i c i n e And Toxicology Department Union Carbide Corporation