Document 5L0ZNRxZQQGXGvzxmbBYzaVY5

FILE NAME: Asbestos Mining (ASMI) DATE: 1931 DOC#: ASMI004 DOCUMENT DESCRIPTION: Journal Article - A Review of Pneumoconiosis !r. : I d o11b i *11 ; v 'j> & l . ,1 U K" *V 0 S' ", . ? * ' t - K H, . 1 -K d d-v d i U :K m Ly i ' i!K - 1! ? A 'U > - K - _ . \ t '1 k v , ( , ' ','i ,-'j ! 1 -! * K IJ w A . t. Ft. 1 s'p*; M^ i ,5 i\ ftffo z -, H ! ! ` 1' - Hi eR ,, 4 K.ll - . - , / v 'j - . L ., f . K, K !| v - c * ? w i 1 1 . *' ?, f : !' *' U A - *-1 . 3 - Id tv 1 , y 4. - , ` *i 1 . 1. - , , s 'll.' . \ "- U r ; ! ' ,' ' ' ,V' *< *'. " - i 1 1 ; i f 5 . > K y rt > K 'i :y ' ,, i t ' d :-v/' 1 . \ i T>1 1 - <. ' w<U-i A.s$y, ^ . K / W Z 'U ( > , OCIOHI K, ! `/ A REVIEW OF PNEUMOCONIOSIS FURTHER ROENTGENOLOGICAL AND PATHOLOGICAL STUDIES* By HENRY K. PANCOAST, M.D., and Kl'GI-NE P. PI'.MlhKGR \SS, M.I). P HI L U H . L I 'HI A, PKNNS 1 I.V \ \ I \ T N 1925, at the request of the Editor of the American Journal of Roentgenology and Radium Therapy, we reviewed the roentgenological and pathological aspects of pneumoconiosis in a paper presented before the American Roentgen Ray Society and published in the Journal''" of that vear. A more complete presentation of the sub ject was made in a monograph"1 published in 1926. The condition has aroused a sur prising amount of interest throughout the civilized world in the short time that has elapsed since then, and especially in .his country. Papers have appeared in great numbers, further experimental work has been done and numerous investigations have been carried out, especially here, by federal and state health bodies in connec tion with many industries. For these rea sons it has seemed pertinent to present a further and up-to-date review of the sub ject to the body of roentgenologists. This increasing interest in the subject is a recognition of the great importance of the condition of pneumoconiosis as a more or less necessary risk of commercial develop ment in the progress of civilization during recent years. This has led to the enactment of adequate compensation laws and regula tions governing the adoption of safety measures intended to eradicate or modify the essential dangers of occupations by many countries, notably the South African Union, Australia, New Zealand, (beat Britain, Germany and one of the Canadian Provinces. In this country we have no federal laws directly applicable to the en forcement of controlling measures or com pensation. In only a few states is pneumo coniosis a compensable disease. Some states enforce regulations directed toward pro tection of workers. It is a condition which is all too prevalent in America without ade- quate oversight, bur largely because of tbj geographical extent of this country and the scattering of the more or less dangerous dusty industries, there is a lack of knowl edge of that prevalence and its seriousness. As the roentgenological examination is the most accurate and satisfactory method of detecting the condition from its earliest to its most advanced stages and of study ing its progress and its incapacitating ef fects, it behooves us as roentgenologists to be familiar with all of the phases of the disease, and not solely with the rocntgcimgraphic appearances with which all of us are more or less familiar. We must play a large part in the education and the public ity which are so much needed to overcome the ignorance still existing, even on the part of employers and employees. We will be called upon for our part in the program leading to the enactment of satisfactory compensation laws which are sure to follow m time. In the meanwhile, civil suits are increasing in number and we must train ourselves in order that we may be able to testify, when called upon, honestlv and justly for the benefit of all concerned. It has been our endeavor in this presen tation to avoid as far as possible any repe titions from our previous publications, and references to them will be made only vV n it may be necessary to better explain be newer phases of the subject. nomenclature hilc it still seems probable that ' dica (SiO.) is usually the active fibrosing audit in the condition which we rccogm a :>s essentially a pulmonary fibrosis, ndh< 'dice to the genera] term of pneumoconiosis still seems advisable just as much now as at the time of our previous presentations of ^ie subject. Some other dusts undoubted!.' * From the Radiological Clinic, University of lYnmvIv.inia Mulic.il School and Hospital, Ehil.idclphu, l 'a. Head at the I first Annual Meeting, American Roentgen Ray Society, West Baden, Ind., Sept, ttj-26, i 9j o . ' V" ' ' 556 Yo> ,' S HA H-'vN Jr p# it > * : [ 0 \1 d .KdcM- if H "j .,r y f*r ' ; V" fi 1 ' , ,r .i H .* t. il > -fi b.i -, hP4' , A M; i* M 1 { , ist ;Vshi ' ' >n a * `.J - - ! tH-' A.. 's -'i.{*-.*1' Henry K. Pancoast and Eugene P. Pendergrass bestosis is ample reason for the presenta over vibrating machines. The heavier ro.k tion of a general rsum of the entire in particles are separated by gravity and u.j dustry, as well as the pathological, clinical asbestos fibers are aspirated out by vacuum and roentgenological aspects of the condi fans into special chambers. The crude >- bestos is then shipped to the various f- 0- tion. . The dust evolved at the asbestos mines tories. All of these procedures are carr: ml contains a moderate amount of silica. The out at the mine bases because of the econ harmful products of the asbestos factories omy in shipment of the lesser bulk of the are almost entirely silicates. Heffernan42be crude asbestos. lieves that silicates such as asbestos under The mining part of the industry is at go changes in the lungs quite like silica, tended by the elimination of a large quant only slower, and that asbestosis is a true ity of dust, which contains silica as well as silicosis. This is, of course, not proved. silicates. Pneumoconiosis is found among The product was mined and the asbestos the workers. Very little has been written fibers were separated from the mineral and about the condition of these men. Recently employed in the making of indestructable we have had the opportunity of examining fabrics several centuries b.c. Attention is the roentgenograms of 58 men from one of called by Cooke17 to a cremation cloth de the Canadian mines, some of which showed scribed by Herodotus 450 b .c. Materials pneumoconiosis. As the mineral rock con made of it have been used ever since then, tains as high as 60 per cent silica, the mine but the most rapid development of the worker's condition is due largely to this commercial industry has been during the directly, although probably not entirely. past two or three decades. The raw product which goes to the factories Nature. Asbestos is a peculiar fibrous and contains very little free silica. _ crystalline mineral composed almost en The most dusty occupations in the indus tirely of silicates, mainly of hydrate mag try are to be found in the factories, in nesium silicate, with varying admixtures of which the work is done in inclosures where those of aluminum and iron. The general the asbestos is refined and is finally spun term is applied to all silicate minerals and woven into the various materials with which have a fine fibrous structure that can which we are familiar. During all of the be split up into long, flexible fibers for the factory processes, a large quantity of tine purposes of spinning and weaving. T he dust is set free, but in varying amounts m fibers will split up in a longitudinal direc the different ones. Most factories, at least tion almost indefinitely. The minerals differ in Great Britain, have devices for removing in their exact constituency, especially as much of the dust. to the amount of iron and aluminum, in Early Case Repints. The first report^ a different countries in which they are found death resulting from asbestos dust ir-na a- and mined. Much of the asbestos used in tion was presented by Murray,s'' in Great Britain and the United States is The man worked in a factory for ten ' i `-rs' mined in Canada. Cooke17 gives the follow mostly as a carder, and was the soie -lir' ing chemical composition of asbestos: vivor, before his death, of 10 other mi n 1 started work with him. 1 he autops- 01 per cent this case revealed pulmonarv fil't.sis- Silica. . . Magnesia............................. . . 40.7 4'-50 a 1 Photomicrographs of sections of the E showed large spicules of asbestos, at leas 7 Iron oxide. Aluminum.............................................. 0.70 they were so regarded at that time. Water....................................................... 17 55 The second case reported in nie^.ic^ The Industry. At the mines, the mineral is blasted, crushed and finely ground in ma chines. The crushed dust is then passed literature was presented by Cooke, 1924. It was again reported by him m ' ? tail in 1927.17 This individual stopped - ' ,1 x* ? 1 - f* . A*,V* I '1 tv iV, t -/v rJ`.h^ 4#' ' ,, 4-*, 'j^ v ' ", ^ ' 11 * k 4 ^ ^ g - *4 .U*J Review of Pneumoconiosis 5* 7 VOL XXVI, No. 4 - T ;n a factory after eighteen years of solfigthhet tfiubbreorscius loinsisa.dTdhiteiosnectoondthceaseeviwdoernkceeds intermittent occupation. The cause of two years in the mill and died. I he physi , m was probably asbestosis and super- cal signs suggested tuberculosis with fibro 7 , 1 -cd tuberculosis. We referred to this sis. Autopsy showed a moderate degree of 1 .. in our previous contribution,51 m 1926, fibrosis with nodules, but quite cellular, , L' 1 1 rely a tuberculous one, especially as and not like the usual silicotic nodules. ^ . ` . " thc first available autopsy report in There was no evidence of tuberculosis. The \ ir literature. In view of the many deaths various asbestos bodies were found in both h have been reported since then, we cases. These cases are of interest first, be \ now concede that this death was cause both presented definite evidences of nroi>iblv the result of both conditions. asbestosis after one and two years' work Kao rally, Cooke was the first to describe respectively, and also the various bodies , unusual and characteristic asbestos characteristic of the disease, and, secondly, Hius in the lungs, and the authoritative for the reason that the second case pre ...scl ,ption of them was made in his second sented the terminal symptoms and died of rheepdoertscorfibthedis icnasdeetinail19l2at7e-rTohne.se bodies will the condition after only two years' occupa The second paper and third public re tion. , port was presented by Oliver, in 1927. He Wood and Page,130 in 1929, reported reported the cases of two women who had awuhtoopdsiyedfionfdibnrgosncinhotphneeucmasoenioaf aaftweromnianne died as a result of asbestosis after working years' work in a factory. There were no thirtv and eighteen years respectively. evidences of tuberculosis. The lungs showed Neither individual had evidence of tuber diffuse fibrosis and thickened pleura. N u culosis. It is interesting to note that the sec merous asbestos bodies were found in the ond of these cases stopped work after lungs, but not elsewhere in the body-. Wood eighteen years' occupation, and did not de and Gloyne,129 in 1930, reported the autop- velop definite symptoms until four years sied cases up to four. Tuberculosis was Inter. . The next report was by McDonald,65 in 19:7. He referred more fully to Cooke s case, and reported an additional one which died'. He thought it reasonable to believe that in the former one the tuberculosis was a superadded infection. His own case did not have tuberculosis. In addition to the two tvpes of asbestos bodies first described t,v Cooke, he added a third, all three of which are now recognized. Seiler,11'1 in 192H, reported another case who had worked twenty-two years in vari ous capacities in asbestos factories, and pro .> n il the typical symptoms of the ad- var i . ase. No tubercle bacilli were found m t" putum. 1 he rocntgcnographic ap- piv y cs seemed not to have been unusual. S: . , n,1"3 in 1928, reported two deaths am< 1 asbestos mill workers in South Atm a with autopsy findings. The first man a mkeel only one year and died of miliar-- tuberculosis. 1 he lungs showed found in three of these cases, and in two, bacilli had been found in the sputum before death. Haddow,36 in 1929, reported on the deaths of Oliver's two cases, and on two others. He stated that the certificate of the last one, March, 1928, brought about the publicity and official recognition of the condition. Since then, the workmen's com- ' pensation act of Great Britain has been ex tended to include asbestosis.93 Haddow states that one of Oliver's patients had tubercle bacilli in the sputum. t Simson103 quotes Hoffman^3 as reporting 13 deaths in 1918 and Collis,12 5 deaths in 1910. These were in health reports, and will be referred to again under predisposition to tuberculosis. Mereweather and Price,73 in . their recent comprehensive report on the asbestos in dustry state that approximately 2,200 in dividuals are exposed to practically pure asbestos dust in the factories of Great t 7 . i ;; 1 i - - ' ? . : ' i , ` ' i \r:m fe I' ' I; : V ff 'x ` A ' .J ' ' f,/.r:" It - * r - 1 ' 1' / -,N l 9, 1 , 'V - .7 . ; ' * - c ' '?- '7 i .q;. ri ,, 1V1i *ir .'fiinmWVii1; ,, -: M? L; a sv. .` if.. ip - "1 i ^, ' 4 K\X 4n f r; Ml 1' . .' -lli u - V i, * 4 Ti t , ' 4 i ;; ^ ) V ` / '* ` *\ - k`n! W 'W . S8 8 H enry K.. Pancoast and Eugene P. Pendergrass v.u Britain. These authors examined jh.l in dividuals among the workers. Of this num ber, 230 had been employed less than ten years, and only 21 over twenty years. All but one of the 363 individuals had been working at the time of the examinations. Ninety-five, or 26.2 per cent, showed defi nite evidences of fibrosis, due apparently to asbestos dust solely. Their table of the time incidence of the condition is of interest. Years at Work Cases Examined 0 to 4 89 i to 9 141 10 to 14 4 15 to UJ 28 20 and over 2 i Showing Eihrosis 0 A 15 '7 Per Cent 0.0 W -5 .12.1 yi-f' 80.9 tercsting to compare the findings in ! ese cases and those of Simson with the cln al table of Merewether and Price. It is o ute possible that protective measures pi. :d an important part in the incidence oi 'lie condition, as shown in the report of ;he last named authors. Appearance of Asbestos Dust. Cooke six has described the microscopic appearance of the components of asbestos dust in some what the following manner: (1) Small fragments of asbestos fiber. The bulk of the fiber is translucent and glistening, with here and there within it opaque particles and minute black gran ules. These appear to be actually parts of the fiber, but their appearance suggests dif ferent chemical composition and physical characteristics. (2) 'Translucent spicules split off from the A ) I This table does not apply to any one group of workers in the factories. The authors have collected also, outside of these sta tistical cases, records of t o deaths resulting from asbestosis, 9 of which were verified by autopsy and the tenth by repeated clinical and roentgenographic examinations. Nine of these deaths occurred from 1927^0 1929. The exposure of the 10 cases varied from nine to twenty-four years. At the time of this writing, Lynch and Smith67 (1930) are among the latest exten sive contributors to the subject, and their report has been the first one in this coun try, at least in medical literature, to deal specifically with the subject. One of their cases, a negro, flied as a result of a gunshot injury after working twenty-eight months in a mill during a period of three years. His lungs showed definite interlobular, peri vascular and peribronchial fibrosis, and also the various asbestos bodies. I he sec ond case, also a negro, died of lobar pneu * monia after four and a half years of con tinuous work in a mill. His lungs showed everywhere a definite increase of young fibrous tissue, in addition to the various as bestos bodies. Reference will be made to ' other cases examined by these authors in . the.description of asbestos bodies. It is in- fibers. (3) Black, brown and blue particulate matter. The black particles are iron. They are few in the finished asbestos product but are numerous in the dusts of the carding rooms. The iron in the finished product was only 0.1 percent, whereas in the dust of the carding rooms it was 18.4 per ceftt. Asbestos Bodies. 'This is, perhaps, the most interesting feature of pulmonary asbesto sis. The various bodies found in the lungs of asbestos workers have been described m detail by numerous authors, notabb H Cooke,16'17'18McDonald,68Simson,in-' Glo) re,-1" Merewether and Price73 and L\nch and Smith.67 The description given by Cooke of the various asbestos bodies is as coniniehensive as that of any other author and is abstracted as follows: (1) Enormous amounts of fine granular pigment like that seen in the asbestos dust fiber. Much of this may be carbonaceous. (2) Large or moderate sized angula! par tides, 10 to 360 microns in size, corre,spun ing to the black, brown and blue particuLjte matter found in the dust. These partu eS are found in fibrous and necrotic amas. singly or in clumps. Because of then size, they might occlude small bronchi. (3) Almost complete absence of the ' e ' , --M '1 '!>: ! '< r; 1 Htjy ft^i * .><? v. ; {'i ; i* i j a V ',!< ; , i t :i r *"**- V.* W; r ' j * *, i v - 'i` 4 'VI-**-!*' m' Sg-2 Henry K. Pancoast anil Kugcne P. Pendergrass Ol JUKI of course, as in any fairly well advanced case of pneumoconiosis. 1 he most unusual feature of the condition seemed to us to be the fact that in both sets of roentgeno grams the appearance seemed to begin more often on the left side than the right and progressed more on that side. This is the reverse of what is the rule in all other occupations we have studied. Merewcthcr7states that it begins on the right side, as one would expect, and the cases we ob served may have been examples of the ex ceptions which arc occasionally observed in cases on careful analysis resolves itself to a fine mottling and linear shadows \v! eh. tow.ird the base, may look like cobwct ,. It is evident that the nature of ttvse changes in the lungs requires the ' 'St type of roentgenograms for their portra, ,t|. Also, the seriousness of what may sen , to be minor changes to the uninitiated re quires a roentgenoscopic study of diaphrag matic movements to make one realize the actual state of disabilitv present. It is evi dent also, as Mcrewethcr states,77 that an opinion as to the degree and intensity of an pi, i .igii asbestosis fibrosis based upon a comparison of roentgcnographic changes with those f .i,, \ shown in standard silicosis films will be an underestimate. Of the 36] cases examined by Mere- - wether and Price, 133 had roentgeno- graphic studies. O f these, 5- were said to have presented appearances of diffuse fibrosis and 22 were suspicious. We have had the opportunity recently of examining in consultation the roentgeno grams of 58 men employed at the mines in many occupations and during periods vary ing from eight months to forte vears. Of this number, 15 showed definite evidence of pneumoconiosis, one was doubtful and 42 showed no lung changes. The longest Fte. g. Pneumoconiosis in an asbestos worker. Male, worker showed a moderate nodular stage aged forty-three, employed for seventeen years and a superintendent at the time of examination. There are two predominant types of fibrosis in this case pcnvascular-peribronchial-lvmph node and fairly advanced interstitial. The latter is indi cated by the general haze toward the bases, and more on the left side. Note the partial obliteration which definite changes were indicated were four years for one first stage case , live years for another and five vears f>i one early second or nodular stage case- i he worst case showed a diffuse third : tee of the left heart border. The size of the cardiac ' shadow is due to ago. Diaphragm etxhceurosldiontec7hinnicqhueeaocfhmsaidney, years ordi nary respiration, and i f inch on forced respiration. fibrosis after thirty-one vears' occupy m o i l . Asbestos mine dust is not comp:; table to that of the factories for manv res OI1S. Some silica is present, but there is n-' rh e any industrial pneumoconiosis. We noted the same tendency to obliteration of the left cardiac border as mentioned by Wood, because of the diffuse fibrosis and the prominent trunk shadows. Wood states that the late stage may or may not show consolidations. Wood and Glovnc1"1 state that the ground glass appearance in late great concentration of asbestos dust ' .he mine as compared to the factory, him o u r own experience so far, wc would not u j anl the hazard at the mine as vervgreat. Prognosis. It seems to be the rs tlier general opinion that the prognosis m p u l monary asbestosis among factorv wot kers is to be regarded as grave without adcq ante protection, in a large number of c uses V &*. *'*r 4 '*'1 * ? .J 1 0 4 v* i < - >I) *; r t - A `A A** i s 1 " , b *4 ' ' ' t ' 4 4L * ; - ) ; vV 11 **\ . tj X ,V ' > k 4i A. * Vv f *\ / bJ ri t r-rwi^pnMTriw11-'w ! -^ 1mn^iMm'uimpu Vol ,\\1. N" i Review of Pneumoconiosis 59.3 Tnionti those who work where there is great concentration of dust. The condition is qipnrcntlv progressive even after cessation of occupation. Merewcther and Price state (h.u with continued exposure to high conccntiation dust fibrosis may be fully devclo;xd in from seven to nine years and Jerh mat result in about thirteen years. With 1-ss concentration, fibrosis may not be fuli developed for fifteen, twenty or :\-five years. Inhalation of dust in |Vi,oi concentration results in a more n i .cd degree of fibrosis in a shorter time t|r n when the concentration is lower. , 'position to Tuberculosis. The cont|jt,, n of pulmonary asbestosis being a new chiu m the pneumoconiosis family, a great ;lll1,,>int of interest centers around the in cidence of tuberculosis. Among the early case reports referred to in the beginning of this occupational section, pulmonary tuberculosis was reported as an accom panying condition in a few instances. Cooke's case had advanced tuberculosis. Simson reported one case which died with tuberculosis and one without evidences of the infection, He thought that we could not as >et formulate any definite opinion as to the frequency or the predisposition. Simson quoted Hoffman4" as reporting 13 deaths among asbestos workers, 3 of whom had tuberculosis. He also quoted Collis12 as reporting 5 deaths from tuberculosis among less than 40 workers at a factory. Wood and Gloyne1'-'1 referred to 3 cases showing evidences of tuberculosis at au topsy. Haddow,!Bobserved many asbestosis cases and among them 4 died. He did not believe that the condition predisposed to the infcct'on, at least not as a rule. Merewether and Price stated that asbestosis ililfi rs from silicosis in the distribution of the fibrous tissue, in more rapid developi r c i n roenrgenographic features and P' s I Is in a evened susceptibility to tuber a 1 , . Merewcther7" states that out of ,r '^e1- examined, evidence of active tn' ilosis was found in three. He thinks tl 'dills there is no outstanding sus ce, !it> proved, he does not agree that the question has been finally settled as yet. . Compensation Laws. Legislation iri,,rnany . countries and states provides for com pensation for silicosis, which is a condition produced by silica. Asbestos is a silicate, and if we arc to regard asbestosis as a silicosis, as has been suggested but not proved,- the latter condition is only in directly caused by the asbestos. Certainly the legal status of asbestosis as silicosis has not been established. In some instances asbestosis has had to be made a compensa ble disease. H ard R ock M ining. This group of workers comprises the largest engaged in any single hazardous industry through out the world, provided the rock is of a si liceous nature. The large amount of dust evolved in the various processes of mining is always dangerous unless adequate pro tective measures are adopted. The drillers and those working with them or near them are prone to be the most exposed. If the fine dust is allowed to escape, it remains suspended in the air for hours. Blasting al ways stirs it up. Without protection, the usual typical symptom-complex and the roentgenographic appearances develop ear ly and progress rapidly, and the Workers are predisposed to tuberculosis. More has been written upon the hazards of this in dustry than those of any other. Numerous writers have been extensively quoted else where. Many more or less similar indus tries and their hazards have been described in detail, such as the drilling in coal mines, granite cutting and sandstone quarrying. The most detailed descriptions of hard rock mining have emanated from South Africa through individuals associated in medical work or other ways with the Rand gold mines. These mines are so often re ferred to in the literature that a short ab stract of the description of the region and of the character of the rock may be of in terest. O liv e r10 states that the first gold mining in South Africa started in the Transvaal in the 70's, and the first gold was taken from the Witwatersrand in 1885.