Document zd6BqDYaR74b1YGZV21jY981m

r,f :* l r tr OF z PLAINTIFF'S S | EXHIBIT 1 EPG- 1 7 Alb T\] Y njAirr nmi i* 2 1 ill 1 1 -U t i . T 1 < -X.--' - * -C. W. M. SCHEPMJ,,MXv-DI'i BIOLOGICAL ACTION .OF- PARTICULATE TUNGSTE1 <-> ' ) a. w. H.:iCHiffU. BIOLOGICAL ACTION. OF; TUNGSTEN: CARBIDE ANB^r*!?^* it BON- ;& *ii* & w. h/ scHwtu'w.D.j-.Difc'Ji'.rj'j BIOLOGICAL ACTION OF TUNGSTEN CARBIDE AND COBALT^^T .W G..W. H. SCHEPERS, M.D;lU<ii7A j >1PI 1 VfMkl EUMOCONIOSIS .:>.* RADON PR0BLE)A*1N.'DEEF`LEVEL -..t <r :-wi <>vrvir3l- DUNCAN ENT. PROBLEMS >JNIDUSf.CONTROL.lN- METAL MINES' : >2 xta^ry^-* - *? ^ DISABILITY FOUND'iN PERSONS.EXPOSED TO 'TTAiiNIN.B.EBERRYYLLLLIIUUMM. COMPOUNDS '''HARRIET!: HARDY? i EFFEOCTSS OF. INHALED ^TALC-MINING DUST:ON j^TjrsAjSjJs E HUJMAN LLUNNGGSS'Is2^&y, .'i "W. H.`SCHEPERS. *U)^-O.lti^T. IONAURTY DISABILITY*1NASBESTOS WORKERS - r *---'- Kenneth w.-smith; NJ.-if ONtMtrir.. DISABILITYY*; ASSSOOCCIIAATTEEDD,WWITH COAL MINING -^Tlis '.t*-.* '' ' W. a- HANNON. RLDuffijSg OLOGICAL STUDY OF THE EFFECTS OF. INHALED PSUM-DUST. ON HUMAN LUNGS -TV' AMERICAN MEDICAL ASSOCIATION Publication B^r > / -^y-- -,. ZT-t**  si M "i ji .4'. f. ;i ;} ;i ! ;t ' -v / f "T, 3> t \ PJ, o&idciLilitij. in s^ldbcstoS 1/Uorl' monarii iCt'5 KENNETH W. SMITH, M.O., Nw York DXEXiSass TaOTwria: rspr r:a;rii:.n:;:jmsii Asbestosis has been described in detail in numerous published articles and texts. While it is true that cases of far-advanced asbestosis may have severe pulmonary disability, rela tively few of the people exposed to the liber develop the disease. Therefore, it is the intent in this paper to mention asbestosis only briefly and then to outline various other pulmonary disabilities seen anion" asbestos workers. , The word "asbestos" is generally used to describe several fibrous magnesium silicates which are different in their chemical compo sition and physical properties. The most important types of libers are chrvsotile. amo- site, crocidolite, anthophyllitc, actinolite. and trcmolite. Total world production of all libers last year aiuoimted to slightly more than 1.500.000 tons. Approximately 95% of the fibers produced were of the chrvsotile variety. 3% crocidolite, and 2% atnosite. Deposits of various types of this mineral are found in many countries, but the largest mines are located in Canada and Africa. Asbestos libers are highly resistant to heat and acids. They have great tensile strength and large surface areas. Because ot these properties as well as their tilamented struc ture, industrial use of these fibers through out the world is increasing. The textile in dustry has u>ed them for many years lo produce blankets, clothing, threads, ropes, tapes, braided tubing, and filters. In recent years, however, there has been an increasing use of asbestos in the insulation, building, and friction-material trades. In addition, the Recorded fur April P>55. Medical Director, Jultm-Manvillc Corporation. 198 fibers can be found in paper, wallboard, shingles, pipe covering, floor tiles, brake linings and brake blocks, cements, putties, and plastics. It should be noted that the facts presented here apply to those persons who have been exposed only to asbestos libers and to r.o other dusts. As previously indicated, industry today is finding many new uses tor the fibers when they are mixed with other dusts. !: is an established fact that when asbestos libers are mixed with silica, diatumaccouj earth, or other potentially toxic dusts, th; pulmonary changes resulting from the inha lation. of these mixtures are not typical of asbestosis. The x-ray pattern may be differ ent, the clinical course changed, or the sus ceptibility to intercurrent infection increase] or decreased. Thus, in making a diagnosis of occupational pulmonary disease, it is highly important to obtain a detailed oeeupi. liotial history, so that asbestosis, silicosis, or mixed pneumoconioses can be differentiated The statements and observations reported here concern several thousand men an; women employed in the asbestos industry in Canada and the L'nited States. In this industry the various mining, nulling, zwi manufacturing operations create some dr,;? containing asbestos fibers. If the fibers up ;0 50ft in length are inhaled cominuaily sufficient quantities over a period of several years, a typical pulmonary fibrosis wi;; develop. It has been demonstrated that fibrosis is due not to the chemical but rath;; to the mechanical action of the libers.1 Th; asbestos fibers are deposited in the termini bronchioles, initiating a tissue response wh.ch coats the fiber and eventually produces wha; is known as the asbestos body. This appear; to lie a defense mechanism of the lung. inerous asbestos lmdies can be tumid in t'r. PULMONARY UISAML11Y IS ASliLSTOS WORK HRS V* t I sputum of persons who liavc li;l only short \ and sporadic exjioMire to the dust. These 4 persons arc healthy and have no demonstra ble signs or symptoms of ashestosis. There fore, it seems more appropriate to use the term "asbestos" bodies rather than "ashes tosis" bodies, signifying exposure to the fibers but not necessarily indicating disease. If increasing quantities of the libers are continually inhaled, the tissue reaction pro gresses, and a generalized, ditfusc fibrosis gradually appears throughout the lower lobes of the lungs. W ith additional exposure, this f- .1 -If f-r.*A^ I! ]i fe -if 1 AJ it. M .< -V -'v r%. A A> . >; "j Fig. 1.--Early asbestosis. t fibrosis will spread to the other lolvs. even| pally causing respiratory cm harm.-milent and 1 finally cardiac failure. | The pulmonary tibrosis resulting from | prolonged inhalation of asbestos tihers will 7 produce a typical x-ray pattern. In early, or t first-stage, asbestosis (Fig. 1), the x-ray f shows a fine, diffuse, homogeneous infiltra? tion througliout both lower lung fields. It ; jbould be noted that this infiltration is bi ts bteral, that it is generalized at l>oth bases, j Hid that the nodular conglomerate patterns ; of other pneumoconioses, such as silicosis, T ire not seen in asbestosis. There is a cond siderablc ainounf of pleural reaction as.soci- 4 Fig. 2.--Moderately advanced aslicstosis. ated with this disease, which may account for the "ground glass" pattern which has been used to describe the typical x-ray picture. In moderately advanced, or second-stage, asbestosis (Fig. 2), the infiltration lias in creased but still is confined to the lower lung fields. The "ground glass" pattern is Fig. 3.--Far-advanced asbestosis. F W ii i,yi|yypif 1 i;^ i p'!*gj f f I lb r . **11 t i ii .-1 i 199 a. m. a. AKLiitriis or isnrsiRiAi. ur.Ai.Tit PC more apparent. and the lu-art lmrdirs are t irrgiiire * has rcjmrted that pulmonary becoming indistinct or slinky. There is mimic iunction studies-on aslestiis workers have irregularity of the diaphragmatic outlines shown that the chief physiological problem and beginning obliteration ot both the cardio- is that of a '`tight'' lung. The vital and phrcnic and the co-tophrenic angles. maximum breathing capacities are lowered, In far-advanced, or third-stage, asbestosii expansion of the lung is difficult, and arterial (Fig. 3), the infiltration still is homogeneous oxygen saturation of the blood is diminished and bilateral, has spread to the middle and in some cases, indicating an impairment of possibly the upper portion of the lung fields, gas transfer through the lung. Diffuse ob but the apices remain clear. The cardiac out structive emphysema, so commonly seen in line is almost completely obliterated, as are silicosis, is not apparent in ashestosis. These the domes of the diaphragm and the co>u>- pulmonary function studies are of importance phreuir sulci. With this picture in mind, it in the proper diagnosis of pulmonary tihrods is advisable to reiterate the observations of and the estimation of pulmonary disability. many physicians, namely, that the x-ray pic (Ji more importance is the fact that these ture should never be used to estimate the tests can often help the clinician in directing presence or the extent of impaired pulmonary the treatment of the case. Unfortunately, function or disability. Many cases with x-ray there are too few persons who arc properly evidence of third-stage ashestosis have been qualified today to carry out these tests and known to carry on their usual work and live interpret the results. fairly comfortable lives for several years. An x-ray survey was made of one group On the other hand, no case of definite disa ot 70S employees working in an asbestos bility has been seen unless there was the mill where the ore was dried, crushed, sep typical x-ray pattern. arated and graded, packed, and then shipped. There is no typical clinical picture for Operations in this plant required the em ashestosis. The disease is insidious in its ployees to rotate through various jobs; onset and slowly progressive with continued hence it was impossible to relate any x-rav inlial.iiioii of the liber. There is a gradual changes to a particular job or to a specified increase in cough and expectoration, some dust concentration. At the same time it could anorexia and weight loss, then slowly in he assumed tltat all tneniliers of the group creasing dyspnea. Cyanosis and clubbing of had licen exposed to varying concentrations the fingers are rare findings. There is evi of the dust. The chest x-rays of these em dence that ashestosis will not progress after ployees were divided into three broad exposure ceases, but this seems to he true groups: () essentially normal lungs- only if the worker docs not develop an intcr- (b) marked linear exaggeration d'-2) but current pulmonary infection. no typical pattern of ashestosis, and (c) def It will be shown that asbestos workers are inite ashestosis. not predisposed to develop more intercurrent Table 1 shows that of the 70S employee* pulmonary infections than arc found in other studied 649. or 91%. hail normal x-rav*. workers. However, when an acute pneu This is oi interest because 204 employees, or t t Es: re- t; mt; ot : f film: ir is a: 1 lung subi< tion deve no'.ec i mere Ts 7 ha as be= stage were jobs interr x-ray 20 ye 9i-. Frc from as be;: cer::c. ether sure; -* which .. oniy : f tratior : that ti ' tibiiity ? fibrosi. ; Me: *' attend h"t ve: t rrenc monitis develops in the presence of an estab 29% of the total group, had 10 or more yean lished ashcstotic fibrosis, the infection is of service, and 2 men actually had worked slow to heal, relapses are frequent, and the more than 40 years ill the dust. patient may lie more susceptible to subse Table 2 indicates that 52 of the 70S em Expo?ur quent pulmonary infections. While it is ployees showed a marked increase of all peri &op!cy true that the disease is slow and insidious in its onset and that people with advanced ashestosis may lead relatively normal lives, eventually the heart begins to fail, and death from cor pulmonale rapidly fol'ows. bronchial markings, although none had defiV llrcKwsre. F.: Pulmonary Function Stmliei b Von Ir.\|wwil for Ten or More Years to Iiiliala:;^ of A'ln-slik. Fillers, read before the Seventh Slrj. nac SymisiMum. W52 (unpuhlUhcd). Espor.r Employ 200 > ` L i'. i fVUtOSARY DISABILITY l.X ASBESTOS If 'OKKIiKS .1 Table 1.--Hmphiyrrj leith .Yrrirf X-fairs i rrpatutr. rr... CopJor**. o- M 5-9 10-U 13-19 sku iV lit 1M 40 44 M S*X> 1 4.V19 I i nite asliestois. Inasmuch as tin- majority trades. The following survey was made in i of these men ltad essentially normal x-ray order to determine the incidence of nnti' films early in their employment history, it occnpational respiratory disease in another 'i is assumed that most of the later increased group, of 1561 men and women, working 1a i lung markings were associated with their in the asbestos industry. subsequent dust exf>osures. Further indica A review of absentee records indicated that e tion of the length of exjtosiire necessary to no valid conclusions could he obtained from e develop x-ray changes is seen when it is this source, because the reason for absence is noted that 69% ot this group had 10 or was given by the employee himself. Sickness i 1 more years of exposure. often was used as an excuse to cover short >e i Table 3 shows that of the 70S employees absences for a variety of personal reasons. >S y, i f. 7 had developed dclinite x-ray evidence of It then was decided to study the claims asbestosis. These men exhibited various submitted for sickness and accident insur b' jtages of pulmonary involvement, hut all ance. AH employees in the survey participated id were working steadily at their accustomed in a plan operated by an independent insur jobs with no signs of disability. It is of ance company. Indemnification was made up interest to note that none had developed only alter the nature of the illness had Ijccii os' z.ray evidence of ashestosis with less than certified by the treating physician. ip- 3D years of exposure. The study included claims submitted over td. Frequently it has been stated that it takes a three-vear period for such illnesses as the m 5 fmni 5 to 10 years of exposure to develop common cold, sinusitis, pharyngitis, grippe, 3s; i asbestosis. The survey reported here con- bronchitis, pneumonia, asthma, and pleurisy. rav < rented mill employees. It is possible that Occupational respiratory diseases and pul V . other operations might have different expo- monary tulierculosis were excluded in the 3up ons tm- oad >Bs; but det- j jnres with other disease experience. Factors - which might inlhiencc this experience arc not 1 ,,iiy the length of exjtosure or the concen tration of dust in the air but also the fact i |iut there is probably an individual susccp- sj tibilitj* to the development of pulmonary ' fibrosis. s Medical literature has given considerable rejKirt. Table 4 shows that of the 1561 employees in the survey group there were approxi mately equal numbers in dusty and nondusty occupations. Of all claims tiled for respira tory diseases. 45% were for employees with dust exposure. Clinical observations for many years had given the impression that a dusty yees ays. >, or ears rked * attention to occupational pulmonary disease, * but very little has l>een rejiorted on the oc* otrrence of nonoccupationn! respiratory disjj[. Qje among those employed in the dusty occupation in itself would not prcdis[>ose a person to more nouoccupational respiratory disease than would a dust-free job. This survey shows that the rate of disease over i c Tabi.k 2.~Fiatplovers with l'-2 .V- /wry etnperi- \ tMjomtn* jti... t*lorcc*. zm~ defi- ies F laticn Sat a. -.i -A t IfVtl IS* I!) S 11 $ 10 11 4*49 11 Table 3.--Employees with ., /.I'i'i'.fLtfl'j' ! S 1 3*-iU lS-& 1 4A.44 0 0 201 i* 1. A. M. A. ARCHIVES OF INDUSTRIAL HEALTH r a three-year period was approximately the same in the two groups. In addition, there was no appreciable ditlerenee in the duration of illness in either group. Animal experiments and clinical observa tions have shown that asbestosis does not predispose a person to the development of pulmonary tuberculosis, nor does it aggra vate an apparently healed tuberculous lesion. In two isolated one-industry towns in the Province of Quebec where asbestos was mined and processed, the incidence of tuber culosis over a period of many years was no greater than in other isolated towns with comparable populations but without a dusty rr- r^ r 'A', i .1 --, ft /` \ w-.r4^; ra /. X-'vCr- > *<?X \ */-**-- * .:. 1 , >r `' /i.ArSi****- Fie. 4.--Klcttrun tnicrograjih, ohrvsoiile asbes tos : X 41100. trade.j lu addition, the incidence of tuber culosis among asliestos workers was lower r/j\< -2; `t * fi i ( SC by di Fi ' * -/>. s' \ -L , 'J h': .$ l mi me l lor v 101 an sti i fc t Fig. ;.--Electron micrograph. aniosite asbes tos: X 4000. & than that among the general population of these mining towns. Conllicting opinions and different reports make it extremely difficult to confirm or deny conclusively the causal relationship oi asbestosis and carcinoma of the lung. Too often a common conclusion is drawn from observations anti experiences with different racial groups. living in different parts of the world under variable socioeconomic roudi. tiuiis and working in diverse occupational exposures. To these variables should be added the fact that there are various types of asliestos filters. f. bee jor St; is i fit* use Th rek car cle: use pre atn r ;ev HCI is r fibe j Fig. 6.--F.lectron micrograph, crocidolite nhej. to.; X 4(itxi. can diac t Parrot. P.: Personal communication to the author. T.mu.c 4.--Xouini'Hl*iiliiHiiil Disease Experience Kut|li*y*a>, ti*.......................................... Knililtiyrm %llti tut Km|*loytr* lth Kim iliht rxiiu>u(c....................... ililiiM for n*Mirat>rr di*oac............................... for re>|dracorr ilkum* Uh <hi( ex* pwure ................................................. ruiinn (or rr|*lr|(*rv H-m'hm* mlth no d*t rxtKMin; .................................................................... tJM\ ? 27 12 15 Aprorarmurr,Wtkiv..ll.i...>..(................i.th....d..u..s.t...e.x.- 3i .Avertrt length ul (iM*nrv ith oo dual exposure, vd................................... 3.1 PULMONARY DISABILITY IX ASHliSTOS ll'OKKF.h'S Iladollct t luix rr|mrted tlml there are several different types of asbestos liliera used by industry today, and these fillers have different physical and chemical properties. Figures 4, 5, and 6 are enlarged electron micrographs of three types of libers used most commonly in industrial processes. The long, soft, and silky chrysolite lihers are found chiefly in Canada, while the amo.-ite and crocidolite libers which arc shorter, stiffer, and brittler come front Africa. Canadian experience with ask-tosis has been limited to the chrysotile liber. The ma jority of industrial processes in the United States use this filter, hut in recent years there is increased use of the amosite and crocidolite fibers. The liritish and European industries use greater quantities of these harsher lihers. Therefore, in trying to clarify the causal relationship of asbestosis and bronchogenic carcinoma, many variable facts should be clearly identified, especially the type of liber used and whether or not other dusts were present in the industrial and environmental atmosphere. SUMMARY Respiratory disease experience among several thousand male and female asbestos workers in the United States ami Canada is reported. ()f all workers excised to the fibers, very few develop asbestosis. Asbestosis is insidious in onset and pro gresses slowly with continued exposure, ausing respiratory emlnrrassnieut and car diac failure. -C : .< 'f ' $ References 2 and 3. I'livsiologicallv, asbrsiosis is lilt* problem of the '`tight*' lung. E.\|ian>iott of the lung is difficult, and there is impaired gas trans fer through the lung. Diffuse, obstructive emphysema is not coiinnoti. There is a typical x-ray pattern which can not lie confused with oilier pneumoconioses. An x-ray survey of 70S employees in a milling operation showed that the majority had normal x-ray patterns, that 10 or more years of exposure were necessary to pro duce x-ray changes, and that no cases of asliestosis were found who had worked less than 20 years in the dust. The incidence of iioiiiHYii(xitional respira tory disease was not increased, nor was the illness more prolonged among workers cxposed to asbestos dust llian among noncxl>oscd workers. Asbestosis does not predispose to the development of tuberculosis, nor docs it aggravate an apparently healed lesion. There are several reasons for different opinions expressed concerning the relation ship of asbestosis and bronchogenic carci noma. Differences in asbestos fibers are noted. REFERENCES 1. Vorwald. A. J.; Durban, T. SI- and Pratt. P. C: Experimental Studies of Asbestosis. A. M. A. Arch. Indust. Hyg. 3:1-13 (Jan.) 1951. 2. Badollct, M. S.: Asbestos: A Mineral of Unparalleled Properties, Canad. Min. St Metal. April, 1951. 3. lladollct. M. S.: Asbestos Fibers: Produc tion and Usage, Canad. Min. & MetaL Atig., 1953. 1 ,X.. 9 1 I \ 203