Document aLo6qYQXdww676b7D3zkzvje

FILE NAME: Union Carbide (UC) DATE: 1983 Feb 17 DOC#: UC391 DOCUMENT DESCRIPTION: Industrial Hygiene Survey Report - South Charleston Plant in t er n a l CORRESPONDENCE ) U N I O N C A R B I D E C O R P O R A T I O N old ^ e s u b v ^ ao. q a n b u ^ v.C t o b b *7--------- Yo UO" Mr* Rb W* R fibbolt M etals H1374 Csy w> Mr. R. A. B u tler Mr. L . A. C ria o rio Mr. &. F . X . Fusaro D r. V. C. Kuryla Mr. . I*. Myera U r. H. B . Rhodes Mr. V. C. Thurber Mr. R. F . Wolff O.t. February 17. 1983 HCL-97 O v w o B '" HSEA. a-.. P-2590 mkc Asbestos Labeling t I have V s t a l e d J a emorandum d ated F ebruary l S . r TKnrber and th e proposed la b e l attach ed W83. * i^ s e d t h ereto. Aicneugn forms o f a sb e sto s r e la te d diee * .h u t fib e rs o f a c e r ta in s i r e body o f e x p e rt opinion which b eliev es t _ ethe tB oanifoBted and shape a r e th e moat harardoos nd . . epideniologLcally by d iffe re n ces in 'b i o l ^ i l produced by pro ^ exposure to d iffe re n t forms of tTW TnSpSS^ g" t . l n . r > '5 3 5 = ^ . ^\.eYadiet the s tl teaent . 1 th ere- consideration " " S ^ , g r i 2 f i f2 & * * . * happy co d iscu ss t h i s fu rth e r v ith yoy. The i c u c h e l perspective, eto taeps oUlAogyihae . for th e ir length. Pl*" ' "M" C " t HCL/bd ^ _ ^(0uwtSfi^u B. C. Lewinsohn, HB.BCh.,FCCP Assistant Corporate Medical Director EXHIBIT internal CORRESPO N DEN CE UNION CARBID E CO RPO RA TIO N o l d r id g e b u r y r o a d , o a n s u r v . c t o s b t d piv< L o o t . an Arm* H r* Hi W* Rcbholz Metals H1374 Coo/> Hr- R. A. Butler Mr. L. A. Crisorio Mr. R. F. X. Fusaro Dr. V. C. Kuryla Mr. J. L. Myers Dr* H. B. Rhodes Mr. W. C. Thurber Mr. R. F. Wolff pau February 17, HCL-97 0^ata Deot HSEA 1983 An, P-2590 sotxct Asbestos Labeling 2! I have studied your memorandum dated February 15, 1983, addressed to Hr C Thurber and the proposed label attached hereto* Although Asbestos is a carcinogen, there does appear to be a dose-response relationship between the amount Inhaled over time and * forms of asbestos related diseases* There ia also a substantial bodv of expert opinion which believes that fibers of a certain size and s S a p e S e the most hazardous and that this theory is manifested have no epidemiologic evidence to coutradiet the * fore suggest the amended version attached to this note tor y consideration. X realize that the wording may not be exactly what feel that the proposed label is too brief and does not ake , . S S a t s necessary to insure safe handling by the employee. 1 would be happy to discuss this further with you. The attached aotea ay be of Interest end help place the aobject It. perspective. I apologize for their length. A - & & euML H. C. Lewinsohn, MB.BCh. ,FCC? VW vnAf-nr HCL/bd A02766 n r r nn007 A SSES S W ARNING -C A N C E R H A ZA RD - b r e a t h i n g a s b e s t o s d o s t era e r a s s w s S a ffl S H O S S . . HANDIX KITH CANE Aim AVOID CHEATING OUST. * EAR " S" " I % TM S i o E B :iv m E>i<llJATE mX " v a m w e n " jS ^ S V i o s h / J 5 S S ^ S l ^ t O R S SHOOED HE NSEO. for industrial use only. * no NOT REUSE THIS PACKAGE. DISPOSE OP U t h TWPEDVF.ART.F. SEALED CONTAINER. 4 2 7 67 UCC 017908 agRF.grOS AKD HEALTH - PERSPECTIVES WffAT IS ASBESTOS? Asbestos i. a geoeric tern used to aesccibe . l l y appearance and their main source of origin are shown in Tabl . The USSR is probably the w o r l d s largest consume of ^ s t o s . S e i n e s oroduced 15% of our consumption in 1978. Canada is ene iea iy ^ of asbestos, with the Republic of South Africa second' 2 S supplies all of the U.S, demand for croeidolite and amosite. It should be appreciated that in the primary and immediate post-primary section of the asbestos industry, i.e., mines and mnuiaeturing industry^ relatively few people are Involved, whereas millions of P P ultimately exposed to apparently ever decreasing amounts i ubtitous in products of the entire industry. Furthermore, the earth's atmosphere and has been since the beginning Tiber* below 0.5 urn diameter ^ d ^ s s than 5 nn ln transmission with the optical microscope and need to be iaentiea oy determination of chrysotile and amphiboles in air and water sample. The latter technique has also been used to analyze asbestos n ng Knocledge of the type of asbestos > "" J * / T c " J ^ e c ! " U1 value because it may be an important factor PP risks involved. Piff.rences in the physical - c^ ^ s S n U ! ,, b e etoe fiber. Ceter.lhe therr partrcsl.r c o TM ^ ^ ^ ^ ,p U t s r s s r iS s r t from blends of chrysotile and amosite and/or crocidolit . - * - WHAT ARE THE PATHOLOGICAL EFFECTS OF EXPOSURE IN PAN? Lposure to asbestos at work or elsewhere may result in five conditions: 1. The presence of asbestos in tissues without disease - e.g., asbestos bodies in the general population. 2 . The presence of asbestos in the tissues causing benign changes ' e.g., skin warts, pleural plagues.* 3 The presence of e.be.to. in the tissue. a th* elopment of malignant mesothelioma of the pleora or peritoneum. 0 2 7 6 8 ii r r n n a n a - 2- M b e o t o . u the 1 . . . ith d - * - - 4. sent with potentially fatal damage to the lunSS 5 ^ulmonary^f ibrosU oc asbestosis). het no cancer. 25 general population; a . cancer of the gastro-intestinal system i n v o l v e oe P and colon and rectum. b Cancer of the larynx. jgo2-SHiati!iS2SlhSiS-2a-i2S5affi-2tS^El ^ - - stomach ^^ ^ ses - - they reach the larynx, tney inlivvoul.vedu;; 1.. t t i - -- > " M S ln lotse aiI"W , gsaylt.tlonal -- 2 of libera *. -- -- diffusion forces in alveolar spaces. , ena A 0 2 7 6 j 1* " S " v i ^ i factors to consider are itemized* O t h physical factor 1itv is dependent upon the size a 1. pespir.bi.llty U P 2. Larger particles ac* * * ^ y escaletor. the longs by * " o {lb,, s Inhaled. ,lt,,.ys and coved It tcspir.ble, 3. s s ^ - s r . : . - - * - - - ~ - stMt,, _ 4. - - t r s : : : : t s s w -- ~ U M li" ire. Of inhaled particles, aside from s i z e pet Ee' Reticles such as ba,, r ; i d ^ t a U - t ^ r hotal asbestos ^ fiber mass. Other * - 3- AU277C aerdynamically equivalent to spherical particles one-half to three-quarters of their measured diameters. Host models consider particles in terms of unit density spherical shapes (i.e., as aerosols), to reach a reasonable agreement between theoretical predictions and experimental observations. In addition to space, the density of a particle determines its deposition characteristics. Differences in disease-producing potentials of fibers may arise from the fact that curly, flexible, soft chryeotile fibers are more likely to be caught and filtered out by this system than the straight fibers of the other forms of asbestos in commercial use. To escape this filter mechanism, the fibers must be light enough to remain in suspension and short enough not to be intercepted by the branching of the smaller airways. Examination of human lungs has revealed straight fibers in the lung up to 200 um in length and also coils of chrysotile which may be even longer if stretched out. Once a fiber is carried beyond the ciliated part of the airway, it may still be deposited and stay there or it may be carried out again with the next expiration of air. The proportion of fibers trapped at this stage still depends on size - long fibers are caught, small ones breathed out. Because in a typical dust cloud there are millions of very small fibers, more are retained in the lung than larger ones. Many of these very small fibers are too small to be counted with a light microscope and can only be counted by examining the lung or digests of the lung under the electron microscope. Their biological effects, if any, are not yet known. In the tissues of the lung, and elsewhere where the fibers may lodge because of transportation in the body by blood, lymphatics and tissue fluid, the fibers may be coated with a brown iron-pigmented material called ferritin, to form 'asbestos bodies'. Asbestos bodies ace thought to be innocuous. Not all asbestos fibers are coated in this way and in humans it has been estimated that for every asbestos body in the lung there are 1,000 uncoated asbestos fibers. It is not known whether this is the case in all types of asbestos or in other tissue. It is Known that asbestos bodies form rapidly, reside in tissue many years and gradually degenerate over the years releasing their fiber core. It is n wn whether these released fibers, after many years, are still capable of causing disease. It is also known that uncoated fibers are capable of causing tissue damage when first inhaled, but it is not known whether they retain this potential indefinitely or are dealt with by some unknown defense mechanism other than the ferritin coating process. Chrysotile fibers have been shown to dissolve in tissue fluids so that it may be impossible to confirm that a person has been exposed by looking for these fibers in the tissues thirty or forty years later, unless exposure was continuous throughout the individual's lifetime up to the me o retirement. Crocidolite and amosite can be identified in tissue even after as long an interval as this, and it has been claime by one inveefcigatoc that it is actually possible to Identify the geological origin of such fibers by the use of electron microscopic techniques. The Physical factors outlined above may be invoked to explain why asbestos miners seem to be less at risk than primary process workers who *n seem less at hazard than those who use processed asbestos under dusty it r\iorti i 4 A 0 2 7 71 conditions. It is possible that freshly mined asbestos is still aggregated in bundles and less likely to be respirable or retained in the lung and thus less likely to be damaging. The more processing the asbestos receives, the finer the division of the fiber bundles and the more dangerous it becomes. Dust studies to support this physical characteristic have been reported. Chrysotile fibers collected in the carding area of an asbestos textile plant tended to have smaller diameters than fibers collected in the dryer and bagging areas of an asbestos mill. It should not be forgotten that primary and secondary use of asbestos usually takes place in highly polluted urban environments by people exposed to many additional non-respiratory toxic agents. Cigarette smoking may be a co-factor in the production of occupational disease - it is not usually permitted underground in mines. There may be a synergy between cigarette smoke and asbestos dust only when they ace inhaled simultaneously, but this is unlikely and difficult to deduce from epidemiologic studies. D. WHAT IS THE EVIDENCE FOR STATING THAT ASBESTOS MAT BE PRESENT IK TISSUE WITHOUT DISEASE? Examination of material from random autopsy series in revealed the presence of asbestos in lung tissue. this finding depends upon the diligence of the search. tissue is examined, prevalence approaches lOOi. These in the absence of any asbestos associated diseases. several cities has The frequency of When digested lung findings can occur DOES A DOSE-RESPOKSE RELATIONSHIP EXIST IN ASBESTOS-REtATED DISEASES? The concept of a dose relationship of response to stimulus is a familiar one in pharmacology. This same concept has been invoked in an effort to explain the biologic response to inhaled dust.5 An important question immediately arises - Why is one person affected and not the person working alongside? A third factor that has to be introduced into the concept is that a given dose-response curve can be developed for a given population (or person), but that it will be applicable only to another population (or person) of the same "susceptibility." Susceptibility may depend upon several biological factors such as the efficiency of pulmonary clearance mechanisms, the anatomic characteristics of the lung/airway system, or the physical fitness of the person. Susceptibility can also be related to immunogenetic factors. Another important variable, not biological, is the differences in work practices and habits of individuals doing essentially the same job. Although asbestos dose-response relationships are evident to a greater or lesser extent for all responses, the degree of correlation is difficult to ascertain precisely because of inadequate records o past exposure in all situations studied. The observed response is usually the result of past, rather than current exposure. This poor correlation has led to the current interest in "susceptibility," i.e., factors accounting for between-subject differences in response. - 5 A02 7 7 F. IS THERE A SAFE STANDARD TO PROTECT AGAINST THESE DISEASES? There is a scarcity of adequate data from which to derive a safety standard which would give a 100% assurance of preventing the diseases associated with asbestos. The present standard is based upon evidence presented in a 19e re^ published by the British Occupational Hygiene Society.' The ^ which this report was founded was obtained from an asbestos textile factory which S d personnel and medical records available for study, as well as duet measurements, from 1951 onwards. The standard assumed that a combination of two variables, namely length of exposure and concentration of fibers during the exposure period, could be statistically analyzed and correlated with^ the earliest signs of the effects of asbestos exposure recognizable by the plant physician. As a result, it was postulated on t h i ? evidence that a cumulative exposure of 100 flber J et *hese centimeter would result in only 1% of persons exposed developing these early signs of asbestosis. The committee speculated that a worker coul work for 50 years in dust conentrations of 2 fibers/cc and only run * risk of developing asbesfcosis. The committee did not propose the s^andar for protection against lung cancer or mesothelioma. The crucial issue at stake is whether exposure to dust levels of 2 fibers/cc will also prevent lung cancer and mesothelioma. ^ ctheC^ ' should the same standard apply to all types of asbestos fibers or should there be an even tighter control on the use of crocidolite7 There 1b circumstantial evidence from the setae factory that the high M d e s s incidence of lung cancer deaths in the heavily workers who were employed before the regulations were `"" 'to-. reeentS horsi. effective in 1933 has been much reduced in the mo.e recently : ^ s e d grouepS i e , the post 1933 cohort, although, . slight excess may still be3 detected even in the cohort first exposed after 1950. Th slight excess is not highly statistically significant and might _be drastically influenced in the future by increasing the *) % ? . S h e r m n r e . If can be explained by the fact that the factory were by no means all in compliance with the stanaara today,^and not until this i. f `^ t a " th " a ^ o excess number of deaths abate. There is no numerical data w i ^ ^ r a to mesothelioma upon which to build a dose-response curve, based authorities do believe that a dose-response has been demonst.ated ba upon historical descriptions of conditions allowing jobs to be classifie as severe, moderate, light and negligible exposures. The present eitw.tlon 1. that in the united states 1 for study, which enables asbestos fiber counts to b e ,- the morbidity or mottslity. The best data still comes to the fctocy l,, the O.K. mentioned previously end it le currently under review by the BOBS. Cancer is an emotional word. KIOSK and OSBX, both under criticism end charged with being inefficient, respond to pressure group, readily and over-react regularly. Nobody seems to know what to do. UCC 017913 - 6 - - v i 'i if the uses of asbestos decline, the deceits in the recordkeeping of morbidity and mortality statistics. AO2773 UCC 017914 REFERENCES Mines, Information Circular, 1977. ditto, R.n.r .button. H i n Comoitty Profil, July Dept, of the Interior, Bureau of Mines. 19 p. " -s - Thompson, J. G. Asbestos and the Urban Dweller. 132: 196-214, 1965. Ann. N.Y. Acad. Scie. . G. I. pulmonary ruootion Ta.t. in bantoa Korturs. Oecup. Med., 16: 49, 1966. Tran., sou. Asbestos-Related Diseases of the Lung and Other Organs. Becklake, M. R. Asoescos Practice. Lung Disease. S: l g"V Job P. Hurray) .nrican Ln9 Association, New York, N.Y., 1977, PP* 55 95. ^ -, r craves W H. Asbestos as an Urban Air Contaminant. Thomson, 3. G., Graves, w. n. Pathol, 81: 458, 1966. Arch. K 22 s s 1968. 0 VruthrA s 4 et. al. A Mortality Study Among others Peto, J., Doll R.r Howard, S . , et. a a 34, 169/ 1 9 7 7 . i n an English AsbestoB Factory, Brit. J. industr. , -- U2774 HCC. 017015 42339B TABLE 1 owwnsusncs of h a m types of asbestos fiber Ciaracteristic Theoretical Foteula Colour Chrysotil* [ S ^ 0 5 1(CK)4 Usually vhite to pale green yellow1, pink1 Crocidolit Ka2FenjFolIl7 (SigOaltODz . Blue Aoosite CFe, Mg)7 (SigO^] (CK)z Light grey to palo brown Anthophyllite TreeLito (Ki. f)i tSig02j] (tH) z Catfts lSi8O 22)(0H )2 Vhite to grey, Vhite to grey pale brown Act inaLite CagCMg.FOs (SiiOz2U <)2 Pil* to irfc jjreca Decaeaosition Temperature* (C) 450*700 Fusion Tecperapire of witcrial (Q 1500 Density g/ca* 2-55 Resistance to acids Undergoes fairly rapid attack Resistance to alkalis Very good 400*600 1200 3'3-3*4 tood Good 600-800 1400 S-4-3-5 Attacked lowly Good 600-850 1450 2-85-3-1 Very Good Very good 950-1040 1315 2-9-3-1 Very Good Good 620-960 1400 3-0-3.2 Attacked llcvly Good Mechanical properties of fiber as taken fitas rock *ample!: 2 Tensile strength ltr kg/ca (Average)(10J psi) 31 (440) 35 (49S) 17 (250) K7) ( C 100) 5 K70) S 70) Young's Modulus 10* kg/or1 1,(20 1.860 1.620 -- - -- (Average)(10^ P*i) Texture Producing countries (23) (27) Usually Flexible to flexible, silky brittle and end tough rough USSR Canada China Rhodesia USA Italy South Africa Swaziland South Africa (23) Usually brittle Usually brittle South Africa Finland USA Moiaabique Usually brittle USA lOTES: *Dehydrwylti or dehydrogenation acco^anied by disruption of crystal lattice and jor loss of strength. Ipn serpcr.tinised dolatite deposits. *0277b n r r nnoift