Document ymn3NXLJG0MxbRKvOzbqDM892

ft V`V/ j-." it'^'V'{'.; (i it*'- ':Ct 7^ v> ; n'-w ; , ; y ':.;? *:'" ,'. Y " I"'.'-' :.<''< ti ; ;'V.-, V - | ;!:?, .i'V:,: \, Y;Y v;7.afrff^ II. S. THEASlIltY DEPAItTMENT 1`IIIH.IC HEALTH Sh'UVK E Public Health llullelin No. 241 AuKUsI 1938 , PLAINTIFF'S ii exhibit Utf'Sa f<r A STUDY OF ASBESTOSIS IN THE ASBESTOS TEXTILE INDUSTRY Ur WALDKMAR (,*. DltEESSEN, Fussed Assislsnl Surgeon J. M. DAl.LAVALLE, PAHsed Assistant Sanitary Engineer THOMAS 1. EDWARDS, Technical Edflor J. W. MILLER. 1'athulogial R. II. SAYERS, Senior Surgeon With (he sisislance of II. F. EASOM, M. 1.. Director M. F. TRICE. Engineer tHvhion F /luluilrlal Hygiene JVurth tarulma State Hoard of Health From the Division of Industrial Hygiene National Institute of Health CHbrAKKU UV IHKKCTION Or THIS SUHUbON UbNERAL IINITKI) STATUS liOVtUNMtNT PKINTINIi d|H(t WA8IIINUTON I ISIS 1` I M ctuUI'wr mU by |he UttpeflnlcailrAl f llwvintuM. Waahlngl. IF. C. * i n \ ' X i ORGANIZATION OP THE NATIONAL INSTITUTE OP HEALTH Thomas Paitican, Surgeon General, United States Public Health Service L. H. Thompson, /Isstsfunf Surgeon (icnerul, Director, National Institute of HeitUh Division of Itiologics Control.--Chief, Senior Snrg. W. T. Hahhihon. Division of Chemistry.--Chief, Prof. O. S. Division of Infectious Diseases.--Chidf, Senior Snrg. It. K. Dveii. Division of Industrial Hygiene.--Chief, Senior Snrg. It. It. Sayeub. Division of Pathology.--Chief, Sorg. It. D. Lillie. Jhntotm of JVtarmueotopj/.--Chief, Pharmacologist Director Caul Voeutlin. Division of Public Health Methods.-- Chief, Snrg, J. W. Mountin. Division of Zoology.--Acting Chief, Senior Zoologist, Willahd II. Whioiit. National Cancer Institute.--Chief, Pharmacologist Director Caul Voeoti.in. National Advisory Cancer Council.-- Executive Director, Dr. Lnuviu II lktoen. iiiii / CONTENTS Hr* .............................. Objectives of the study..... .................... -............. -- ...................... ------1 lie working environment.................. .................................. Methods and instruments used in the study of the working environ ment... -................ -............. ...... ............. ....................... ................................. The manufacture of asl/cstne textiles.................................. . .............. .. Preparation ______________ _______ ...... ............................... ......... Curding........................... ................. ............... . ............................................ Spinning............................ ................................. ............. ................................. Winding, twisting, and spooling.............. ............... ........................... Weaving........ .............................................. ..................................................... Ilrakc-land nuuiufacture_______________ _____________ ____________ _ llritish manufacturing methods............... .......................................................... Occupational analysis and a description of the chief occupations......... Preparation............................... ................................... ........................ .......... Carding......................................... ........................ ............... ........................... Spinning.................................................... .. .................................................. S|MM>Ving, twisting, winding, am) treating............................................ Cloth and tape weaving......................... ..................................................... All other.......... ............. .. _ -------- -------------------------------------- --------------- ltesults of the engineering study........................................................................ Dust studies..................................................................................... -- . Nature of dust found in aslrestos 0 utile factories................... .. . . Com|Misitioii .................. ................. .......................... ............. ............. Particle size....................................................... ..................................... Dust concentration in different occupations......................................... Preparation............................... ............ .................................................. Carding................ ............... ................. -................................................. Spinning.................... ................................... ...................... .. .............. .. Spooling, twisting, and winding....... ................................................ Itroadcloth weaving........ ...................................................................... Tape, wick, und hrake-traud weaving....................... .................... Cord, rope, sod braid working......................... ........ ............. .. Ilrake-hand finishing............................................................................ Miscellaneous oecii|>utions.....................................,............. -.......... Previous dust ex|H>snru.......................... ............................................ ...... ........... Interpretation of dust counts........................... .......................................... .. The control of aslrcslos dust................................................................................ Preparation department............................................................................ .. Widowing.............. ......................................................... ....... l .. Piling......................................................................................................... Picking............... ................. ................. ................................................... Carding...................................................................................................... ........ Spooling and twisting.................................................................................. Weaving.............. ................. ................... ..................................... ................. Inspection......... ..........................................................................................-- Soimnuiy of the study of the working environment................................. m l 2 3 3 4 8 ft in it 13 IA 10 18 18 18 18 18 11) 10 lft I 11/ 23 25 25 20 27 27 28 2U 30 30 30 31 32 33 33 34 35 35 30 37 38 3ft 40 Ul fz=xS ~ s sSH ^ V Sfutialicul description nf employees........................................ ................. ........... .... Occupational hiatnrirs..................... with other industrial worker**.................................................. - Medical study___ .............. Procedure........................................... ............................................................ __ Post mcdirul history ................................................ ................................ .... Symptoms of u*lestosis............ ............................................................................ X-ray findings..... ............................................. .................. ................................. l.nng-licbl markings........ ......................... ........ ........... ......................... Diaphtagm............ .................................. -............... ..................................- Physical findings.............. ........................................ .............. ............................... ('host expansion................................. Respiratory rule................................................ Clubbing of lingers ami curving of nails................................................ llenrt defects........................................................................ A.sltcstns cornu................................ ............................................. ............... laboratory findings .............. .......................... ............. ................................. Asliestosis liodies._............................... Itcsulls of tents on urine........................... . ........ .................. ....... The diagnosis of asliestosis........ ................... ... Occupational history................................................. X-ray findings.... ................................................ .................................. Classification of lung-field markings........................................................ Symptoms.................. ..................................................... ........................... Representative case historic*................................. Incidence of asbestosis.......... ............... ..................... .. ....................... .. Threshold concentration of asltcstos dust____ . Incidence of aatiestobts in dillcrcnt occupations................ ........................... At*lH'fitoMH in (ircut Itritain and the United Stales______ _____ _______ Puthologirul findings in asliestosis............................................................................. Cross up)H`nrum*e...................... ....................................... ...................................... Microscopic appearance........................... .. ttcleelcd autopsy report*._....................... -................. ................................. Acknowledgments - -.................................................................... .. ......................... Summary of medical finding*....................................................... Annotated bibliography................................ ................ ............................................. rKo 45 45 40 48 48 49 60 64 54 01 02 .03 05 00 00 08 tit) 09 73 74 75 75 75 77 77 89 Dl 91 95 1)0 90 90 KM 115 110 118 Ki*nr ILLUSTRATIONS 1. Vacuum cleaner bug arrangement for collecting biih|tended dost sumplcs 2. Plow sheet of American practice....................... ................. ..................................... 3. Mill for crushing asliestos filler................................................. ......... ..................... 4. Ply o|ener or widower (note Cxhunul) .................................................................. 5. Ivduir ded carding muchioc*.............. ........................ .................................................. 0. Spinning milieu................................................................. ........... ................................ .. 7. Twisting inuehlnes...................... ....................................................................................... K. Kfcltuu ;ted braider................................................................................................................ 9. Itopo making machine.................... .................................................................................. t(). lhoud-lolh weuving loom...............................- ..................................... .. ................ 11. Uruke band weuving loom showing Ihrco nf the six sections with woven ban 1*....... .............. ..................................................... ....................... ................. ...... , |2. Flow rbeel of Rriti.sh practice................................. ......... ..................................... 13. (iross np|Huraneo of sns|eiu|ed dual Collected with vacuum cleaner device (see |ig. I)............................................................................................................. 4 5 0 7 8 9 10 It 12 12 13 14 21 VII !'*xe 14. Microscopic appearance of su:|Mmdcd dust collected with vucuum 1 jn , device at 2110X....................................................................................... 22 15. I si.tiu.-Pd piling bins.......................... -............. ........................ -- ---------------- 31 10. FxhausL ventilation used for piling o|Haratioos (Itriti-sh practice)........ .. 35 17. Schematic drawing of exhuust system used with picker machine........... 30 18. Vertical exhuust ventilation applied to au unenclosed primary carding machine................................................ ............... .................................................... 30 19. Totally enclosed exhausted primary carding machine................................ 37 20. Klcvalion ami plan for standing exhaust system................ ........................... 37 21. Hxhausled s|>ooling frame................................................................. --............. 38 22. Exhausted twisting frame......................................... ............................................. 39 23. Kxliuustcd broadcloth loom.......................................... ........................................ 40 24. Detail of exhausted loom shown in figure 23______ t ..................... 41 25. Detail of exhaust used on Rritish ty|>e loom............................................ . 41 20. lCxhaustcd brushing and inspection table......................................................... 27. Form used for recording occupational history................................................ 41 45 28. Form used for recording past and present medical history.............. ........ 49 29. Percentage of persons, classified by dust ex|Mwure, who had certain disorders........................................................................................ .......................... 62 30. Percentage of i>crsoiis, classified by lung-field markings, who had cer tain disorders................................. .......................................... ............................. 63 31. Form used for recording X-ray findings.............. ........ .................................... 54 32. Scheme used in classifying X-ray markings____________________________ 55 33. Percentage of males, classified by age, who had certain lung-field marking*...................... ................... ................... ................. ............. -............. .. 50 34. Kclulion of ground-glass lung-field markings to length of employment. 58 35. Kclalimi of ground-gluss lung-field markings to dust exposure............... 58 39. Incidence of ground-glass lung-field markings in relation to length of employment and dust concentration............................................................ 69 37. Hclulioii of diaphragmatic fixation to dust exposure. Three stages of diaphragmatic fixation are represented......................................................... 00 38. Form used for recording physical findings...................................................... 03 39. Photomicrographs of asliestosis bodies found in sputum. Fnlurged 530 times except K which is enlarged 310 times. A scale ruled hi units of 50 microns, has lieen drawn lieside each asliestosis body----- 07 39a. Asliestos corn on thumb of 30-year old man employed 4 years in the curd mom of uu asbestos textile factory...................................................... 70 40. Portions of chest X-iuy films which illustrate the successive changes brought about by long-continued Inhalation of asliestos dust............ 70 41-61. ('heat X-ray films illustrating individual case historic*....................... 78 88 52. Photomicrographs of lung sections showing the prcscnco of nodulur fibrosis ami emphysema in a silicotic lung and diffuse fibrosis and emphysema in mi n i siotic lung. A section of a normal lung is shown for comp > i* - Magnification I0X............................ .. ............ 98 53. Aslx'stobis body in intru-nvcoleolar connective tissue. Practically no fibrosis in this area, ('use 11-21 Magnification 1,000X. (Army Medical Museum No. 62,255)........ ............. ................................................... 61. Asliestosis liodics accompanied by giunt cells in an Area of fibrosed lung tissue, ('use 11-21. Magnification 705X. (Army Mcdicul Mu seum No. 52,255)................................................ -..................-........................... 100 55. Case II 21. Itight lung. Markedly thickened pleura with fusion of jnlerlobar pleura. l)ense fibrous tags over entire surface.................... 102 (A Stir -- pa Zi o SB ,7! a. rH wwMtofsnni VIII t'lgur* riK 50. Cano 11-21. I-tft lung. Pleura much thickened. Fewer Hhroim nd- lti`sion(i thun were initial on the right hnig.................. _............................. 103 57. Cukc 11-21. Section of light lung. Atlvnncctl tobostohia. DtHtemlcil lironehi ami air at both ajax and hose. Diffuse fibrosis throughout lung substance and thickened pleura................................... 104 58. Case 11- 21. Section of left lung. Distended bronchi umi air spaces at apex. Kuthcr uniformly distributed fibrous and emphysematous ureas throughout rest of tong.................................... ...................... ............... 105 59. Chest X-ray of case II -23, 15 months before death.................................... 107 00. Case 1123. KigltL lung. Entire pleural surface covered by dense fibrous tags......... .......................... ...................... ............... ................................... 108 61. Case 11-23. ]>efl lung. Very few Olio fibrous tugs are noted on the pleura......... - -....................-............................. ...................................................... 109 62. Cufir 11-23. Section of right lung. Moderately advanced aslatstosis. Fibrous areas and emphysema uniformly distributed throughout the lung Hultstunce............. ....................-................................................................... 110 63. C-use 11-23. Section of left lung. Shows less involvement than right lung------------------------------------------------------ --------- --------------------- --------- U1 64. Case 11-25. Chest X-rays taken 15 months und 1 month before death. ' l'art of the difference Ixitwecn the two roentgenograms is duo to a diflerenco In X-ray technhiiiu............. ............................................................ 113 65. Case 11-25. Section of right lung. Early asbestosis. Uniform dis tribution of fibrous areas throughout lung substance.... 114 I ABSTMACT Ashestosis, a lung disease caused by long-continued inhalation of asbestos dust, was the principal physical defect found on mcdicul examination of 541 men and women employed (or recently employed) in three asbestos textile factories. The primary effect of asbestos dust seems to ho initiation of fine, interstitial, pulmonary fibrosis which wus not observed to progress as hir us flic nodular stage. This fibrosis was observed in post-mortem examinations of three former asbestos workers. During life, lung fibrosis can be detected by X-ray examination. Tho more important symptoms of usbeslosis are pro gressive dyspnoea, variable cough which sometimes raises blood* slreaked sputum, uud loss of weight. The processes that produce dust in asbestos textile factories were studied and recommendations for dust control arc incorporated in this report, tinmigli dust counts (242) were made in all parts of these factories so that tho dust ex* postiro of euch worker can he estimated. The percentage of persons In different occupational groups who were affected by ashestosis or liny of its symptoms varied with the average dust concentration to which they were subjected and with their length of employment. The only cases of ashestosis, three in numlier, found below 5 million particles per cubic fooL were diagnosed as doubtful; well-established eases occurred at higher concentrations, it nppeurs from these duta that if ushestos dust concentrations in (lie uir breathed are kept below this limit new cases of ashestosis would not appear. . (IX) vt ZX O 3 ui *n I I '"`IIHIOi A STUDY OF ASBESTOSIS IN THE ASBESTOS TEXTILE INDUSTRY INTRODUCTION l/l itfc p* ZZ o 5|2 f; O. f i *** amtx Scvenil important properties of asbestos Inive led to its widespread use in industry. As everyone knows, it is noncombiiKlible and an excellent insulator against heat and electricity. Fewer people seem to be aware that its libers are sufficiently long and flexible to be carded, spun, amt woven like wool, (lax, or cotton. Utilizing these properties of asbestos, industries have been developed in this country which employed more than 0,0<H! men and women in slightly more than 00 establishments in 1935. Another property of asbestos has been discovered more recently. When asbestos dust is inhaled daily, ycur in and year out, u lung disease, termed asbestosis may develop. In many respects asbestosis resembles Bilicosis, but it difTcrs from silicosis in sevcrul important particulars which will be discussed in tho medicul section of this report. The first record ol a case of asbestosis seems to linvo been made by Montague Murray in 1000. The first complete description of the disease and of the "curious bodies" seen in lung tissuo and sputum appeared in 1027 when Cooke (0) and McDonald (22) reported two eases of asbestosis and listed their reasons for believing that asbestosis bodies originate from asbestos libers that reach the lungs. The pub lication of their pallet's aroused gencrul interest ill the subject ami numerous papers appeared soon afterward. Hoffman (40) appears to have been the first American to call attention to the magnitude of (lie asbestosis problem. In 11118 be reported that 13 deaths from I'. asbestosis bad occurred among asbestos textile workers, and uhout (bo same time Pancoast, Miller, and laimlis (20) reported on 17 cases of asbestosis. Mills (20) paper was the first patladogical report on asbestosis published in < I 'oiled States, and in the same year, 1030, lynch and Smith (38 j n-porled on asbestosis bodies found in the 'll sputum of asbestos workers. Because several satisfactory literature reviews of asbestosis have t appealed in recent years there seems In bo no need to present a com plete literature review in this report. Some of the more useful litera ) ture reviews have been listed in the uimututcd bibliography. In ; * Mcrewctlu r's (25) review emphasis is luid on the relation of asbestosis (l) to working conditions. The clinical aspects of (lie subject are well treated. (Hoy lie's (III) discussion of (lie pathology of nshestosis is particularly helpful. Middleton's (-17) Milnn lectures on pneumo coniosis contain a section on ushestosis. KkI,,,, (I ' has siiniimm/.cd the literature reports on 28 fatal eases of nshrsto. is. "Active pul monary tuberculosis was prcscuL in 0 instances of the total 28 cases; the fatal outcome was primarily the result of tuberculosis in 3 instances. " OUJECTIVES or THE STUDY 'The Public Health Service was requested by the State Hoard of Health and the Industrial ('oinmissioii (administrator of the Worknun's Compensation Act) of North ('arolinu to assist them in making an engineering and medieal study of health hazards in the asbestos textile industry.1 The objectives of this study were threefold: (I) To make u medical study of the effects of long-continued inhalation of asbestos dust on the human body; (2) to identify the manufacturing processes that create dust und to recommend practices nud| when necessary, equipment (hut will reduce the dust exposure of workers; and (3) to find out what concentration of ushestos dust can he tolerated without injury to health. `I Iti. ie|iie-4tn( uitr of ilm llrsl u->e of SutmI ScciuHy I11111J4 fur * fii|nitite l`fo)cCt i-mriotl (Mi l.y lit* 1`ubltc Ik-.tllh ScM'lto uml u Sl.tlo lit-ulili ilt'|.nrliOfOl. TIIE WOIIKINC* ENVIltONMENT METHODS ANDINUTRUMENTS USED IN TIIERTUDY OF THE WORKING ENVIRONMENT The evaluation of the working environment and its relation to the health of workers forms the basis of ull field investigations conducted hy the Division of Industrial Hygiene. The procedure followed by this Division is described in Public Health Hullotin No. 217 (2). Therefore, only a brief discussion of the subject is presented in this report. The study of an occupational dust problem begins with a preliminary survey designed to obtain data on all the occupations in a given plant. It includes the number of workers employed in each occupation and the materials used in each process. The survey also reveals tho number of workers cxjaised to a given liuzurd. Following tho pre liminary survey an evaluation of the occupational environment is made. In the dusty trades this includes u determination of tho amount of dust present in tho uir, its composition and particle size and the measurement of the effectiveness of exhaust systems where it s are used toeontrol dust hazards. Tho hitter, in this instance, involved airllow measurements of several exhaust systems by means of u pitot static tube. The effectiveness of these systems was determined by dust counts. THE MANUFACTURE OF ASUESTOS TEXTILES Approximately DO percent of the ushestos used in these plants is obtained from Canada. The remaining 10 percent comes from Arizona or South Africa, und, infrequently, from Kussiuii und Aus tralian sources. Much of the machinery that is employed for the muiiufuctiirc of ushestos textiles is identical with tho nmehiiiiTy used for the production of cotton und woolen goods, (.'rude asbestos fiber is sent first to the preparation department and then, in the order mumd, to tho curding machines, spinning frames, winding bobbins, twisting machines, spooling frames, and finally to the looms and miscellaneous fabi irating devices. 'Hie four plants investigated in flic present study full naturally into two classifications. Two plaids convert crude asbestos and raw cotton into ushestos yam uud woven goods, hut do not prepaid the (3) 1 VI U. fc- _ pa r zx o 3* Q. rH i-a omu 4 products for the ultiimile consumer. The oilier two plnhts purelmso Imth nshestos yum uml unfinished woven asbestos tape. These establishments weave brake bunds and convert their own woven product, as well us purchased material, into linished goods. The practices followed in the plants studied are seheiualiealiy presented in the How sheet shown in figure 2. FltePAH ATION Crushing.--The first step in the mumtfac- ture ofushestos textiles is the crushing of the cnido stoek in a mill ing machine. This is accomplished by large iron rollers wliieh re volve in a steel pan in whieli the crude ma terial is placed. (See lig. :M This operation sepaiutes the fibers and loosens the impur ities that survived the cohhing of the ore at t he mines. The crush ing operation does not produce niiieh dust, the fibers being disin tegrated hy a mashing and twisting action. Most erode ore must he crushed for 20 tuitmlcs, although in some cases it may he satisfactorily disinte grated in 5 minutes. The crushed asbestos Figure i - Vacuum cleaner 0ag Arrangement FOR COLLECTING SUSPENOEO OUST SAMPLES lias a iimtlcd appear ance. Following tho crushing, the asbestos is rcplueed hy hand in the hags for delivery, to the willower. - WilioUHinj.-- The widowing or opening of the asbestos is essentially U cleaning operation, 'fhe willower heats and shreds tlm malted Km C*Uw I Iriktr, r Oftfttr FLOW SHEET AMERICAN PRACTICE Crwd* litwiUi l Cruabar 11 Iwtr (IkIMm prlaary | craaalad) ^ --IMUIM4 PmiIri--- Stcondir; Scrota muiimiI rHU| Malarial Mca*ir..U, Bom fluh da Ml MplOf *#<- acraaaad i|la to r* ct>o* rara(IbuiM1mUp*ta*) rfir| mhmU| product* - tikanla* likMit -- MUrlU Catlactad 4 Ny lllloodr tlMtalat acraaa) 44 ftalalnad fuila| Call** S|} la aii for point 4 loo |rJ eooMt product a'f'ra. - COTTON ASMSTOS MITVW 4 fr UU17 Mckar --(tncludo* addition nf . *11) ----(--N- Solaact MInM/pflafteetkaahraalnp only ana Mckln* tba Mtarlal la ptlaoaoaaad.) tfarauyfa 11 unl -- -- - HUM lock Man Card* Paaalit Scrooo tala load (Larfaly aand) (Sfeart ftfaraa) old ta caaaal told to yolot anufacturara and papar aamifatturarn - --M-JpacUl card for alactrical Laaulattoa and aaekUwj kaorlnf pMklAf SpUalai fraaaa (rlai aad mla Kota* Tka pro- I auct daalrad par- j aroa 14a aaouaaca I a\1fotahjat# apart- ), T*IIU| (M|llf ------ 4*UU| - iaraN (Tap*, alcfc and faraka Ilatnil CloU iMilaf (**t A dry) I laipacttM &old ly aona plant* aiUiut fulbar procaaalof Harlot Traataaat (l*>pr#fnatlaa allfa altfaar r*|*tabla ratio*, *r aapfaoltla caapouada) faabod ) riaiaHad tlarludt* calaadarluf, plnilii, arlUUd aod aUaalllLd) l Naikat Figure 2 Finw `im'rr or amcrican fiur in.r 6 asbestos musses into individual libers mid removes some of the rock, 'i'lic ushestos fihers flint are retained are delivered directly to a storage bin or conveyed to one hy |inciimatic duct. (Sec fig. 4.) The ma terial falling to the floor is screened in order to separate the grit from the short fibers. The grit is sold to cement manufacturers and the short asbestos fibers to paint, paper, and roofing manufacturers. The willower is fed manually hy a laborer who liffs the crushed asbestos into the willower hopper hy means of a pitchfork. The heating and combing action which takes place within the machine produces a large amount of dust which escapes from the loose-fitting enclosure. The production of dust is increased when wuste asbestos, recovered from the cyclone separators which form a part of the dust- 7* of cotton u *1 depends upon the quality of the widowed ushestos fibers used. As a rule, from 5 to 15 percent hy weight of all the asbes tos textiles produced in this country is cotton. the plants studied, the mixing is accomplished in two steps, the first consisting of plucing the cotton and nsbcsU>9 in alter nate layers in a pile upon the floor, ami the second step of feeding the mixture into a picker inucliinc. The hatch making, or the placing of the cotton ami asbestos, is known us piling. It is productive of much dust since it is necessary to spread out both the cotton and ushestos into uniform layers, which involves the use of a lake uhd much trampling of the materials. Viekinij.--After the mixture is mude, it is lifted into the breasthigh hopper of the picker machine. The material emptied into the V) Jfcfc ON PS zz 5& removal system, is willowcd for reclaiming purposes. This Intter operation is culled fly widowing. At one of the plants studied, the widowed asbestos is passed over a vibrating screen. This operation insures a cleaner product, since additional grit and short fibers arc removed. Where a second screen is not available the asbestos may he passed Ihioiigh the willower a second time, a practice which is followed at two of the plants studied. Tim screening of asbestos is a decidedly dusty operation. A/ixiuy.-- T he asbestos fibers consist of blends of various grudes und often include a certain amount of waste recovered hy the fly willower. This process is followed in order to obtain end products with the char acteristics demanded hy the market. When a butch of asbestos baa been made, it is then mixed with cotton. Asbestos fibers must he mixed with cotton before they can he spun and woven. The ainmml Figure 4.--Fly opener or willower (Note Exhaust). hopper displaces air in the hopper which muses dust and fibers to escape upward into the face of the worker. In addition, the cylinder am) accessory rollers of the picker machine operate at a high speed and much line uuitcriiil i)r fioin the many small openings in (he frame. The dust that i ninnrd out of the machine, together with that produced in the feeding operation, makes the pickerimin's occu pation comparatively dusty. In some plants two pickers are oper ated in scries und in others only one, through which the material may he passed several limes. In either case the picker discharges directly or hy pneumatic duel into a collector bin. Where only one machine is available, however, the pickerinan must move the inaterinl hy pilelifoik from the collector hill to the. floor of the picker room for its recirculation through the picker. At one of the plants studied there are two pickers operated m series and connected hy pneumatic 4imv :is - J j 8 ducts. Here ilio collector l>in is also the storage lin. In order to prevent the mixed nmteriul from iiccmiitilaliiig in a steep pile a man is stationed in the stock hiu at ull times. This occupation creates considerable dust, since the cotton-asbestos mixture is delivered into tlio bin hy overhead duct discharge. In order to reduce the dust exposure of the stock-bin man, bis position is made interchangeable with the pickermun, each of whom spends a half of every day in the stock Inn and a half duy at the picker. In the plant having only one picker, the mixture is trucked from the collector bin to the sloruge bin. At one of the plants studied, exhaust ventilation is provided for the picker machines and the mixed stock storage bins. Oil spruys are 0* picker, the 'nipd difference being that tho roller und cylinder sur faces urc studded with fine steel bristles rutlicr than Iurge books. Some of the rollers straighten tho libel's by combing out the tangles, while others dolT, or remove, them from the combing rollers ami the cylinder. Aside from these muin features, the two units differ slightly. Tho breaker card is equipped with u feeding hopper similar to thut used on the picking machine, while the finishing curd is provided with u device for forming the carded libel's into strands. In the plants studied a system of conveyor lattices transfer tho carded fibers from one mucbiiio to the other. Tho outside strands of roving'ioo returned l/l _ Z23 X Mxl o .n Q. *H I figure 5 -Exhausted Carding Machines. frequently used within the picking machines in an attempt to prevent the formation of dust. CAKDINU From the storage bins the stock, as it is ctdlcd, is hand-trucked to the curding inn bines where it may he piled upon the Hour or fed into the hopper of l> e breaker card. The cards p< rfoim several duties. They give the libers nil addi tional mixing, i-rruugc them in parallel positions, uml form them into loving. The I uni roving is applied to the strands of parallel libers thut are produced. A curding unit consists of two almost identical machines. The one thiough w liicli the col Ion-asbestos mixture passes first is termed the breaker card, and the oilier, (he finishing curd. The two nmchines are quite similar in ihnt a huge revolving cylinder with sevend accessory toilers perforins the major portion of the work. (Sec fig. 5.) 'Dio caiiling operation is quite similar to that of the Figure 6.--spinning Mules. to the picker for reworking. The remainder of tho roving is wound on long rollers with itunged ends, called jack spools. The bristle-studded cylinders of tho carding machines revolve at high speeds and much lint is thrown into the atmosphere. The effect produced hy the revolving cylinders and wheels is similar to that of a fun, uml ns a result much of the dost remaining on the stock at lhi9 point, us well us nsbcsto9 and cotton libers, is blown into the air. All niiding inuchiiics studied ei<- provided with exhaust ventilation. While practically all nl in i .\mg is spun into yarn, some of it is marketed without further processing other than winding on spools or into coils. In this form it is used for electrical insulation and for conversion into packing for machine hearings. SPINNING The jack spools conlaiiiing the roving may he conveyed either to the mule spinning machines shown in figure (> or to the ling spinning frames. The spinning, on whatever machine performed, is a twisting npcruLioii which imparts strength |o the strand of fibers by inler- ii 10 lurking or meshing thorn together. The ring spinner twists the roving ns it is wound on a spindle, while the mule spinner performs tho sumo treatment in two operations; first, spinning it in 5- or ti-foot lengths und then winding it on n spindle. The ring spinner makes a yum that is stronger and better in many respects limn that produced on tho mule spinner. WINDING, TWISTING, AND SrOOMNU The spun yam is converted into stronger thread in |wo operations. It is taken first to the winding machines where it is transferred from spindles to tubes. After being wound on tubes, the yarn goes to tho twisting machines where the thread from two or more tubes is brought together find twisted into one thread. In the twisting operation the thread is frequently strengthened with brass, zinc, or copper wire, or Figure 7--Twisting Machine. with cotton twine. Following the inilia) twisting operation the yarn limy return to the winders for placing on special tubes, in which foim it is marketed. Then again, it may he conveyed to the cop or twill winders where it is wound into spindles for use in Ihc shuttles of tho looms. There an; a variety of winding operations that prepare the yam in sonic particular manner for the market or for use on certain types of machines. Likewise, there are u variety of twisting and spooling operations. (Sec fig. 7.) The winding and twisting of the yarn is followed hy a number of more or less related operations. The thread may he converted into cloth, tape, wick, hiake lining, tubes, braids, or fonned into iopc. (See tigs, ft and tt.) A smalt amount of the product of the winders und twisters is treated hy passing through a sizing compound, and subsequently dried on reels before being wound iigain on lubes for tho market. ' 11 The weaving of asbestos is done on looms that operate in the con ventional manner. Both cloth looms and tape looms are used. (See tigs. 10 and 11.) On tho latter, brake lining, ushcslos tape, and wick for oil stoves ure woven. The tape looms differ from tho cloth looms in that the wurp is segregated into several strips of material and in that there is a shuttle for cuch strip of wurp. The weaving of ull strips proceeds simultaneously; one ineehunisiu operates all shuttles ami a single reed suffices for all warps. Looms for tape weaving are made in multiples of h spaces up to ns many as 30. Both dry and wet weaving are employed for tho production of both doth ami tape, in ivet weaving the warp is passed through a shallow pan of water ami the cop (for use in the shuttle) is dipped into water. Dry weaving of broadcloth produces much lint and dust. The threads of the warp are continually rubbed past each other as they are moved from positions above or below the line of the shuttle which is shot from one side of the loom ciURE 8 --Exhausted Braider to the other at each change in position of the wuip. Fiber fragments are rubbed from the threads at each change in their position and the fanning of the air hy the moving niiidiinery carries (hem into the atmosphere in and about the loom. The same machines ure used for both wet and dry weaving. In the nmnufactiuc of asbestos woven products at some id the plants studied, the wurp is formed on individual looms hy harnessing the thread finiu many spools which are hung on creel nicks. At others 12 (lx1 warp is fii>*t wound on a beam from the imli\ idual spools and then trunsfeiied |o the looms. Tim hitler practice. makes a morn compact weaving unit ns creel rucks occupy s-evcnd limes ns much floor space ns the loom. The rreel racks me attended hy a worker who is kept J3 comhustihk Some asbestos wick is packed for the market without fm I in i licntinent. Asbestos tape is usually sold to oilier industries. Some plants that weave brake bands sell it as a crude woven ribbon of fabric to finishing factories, while other munufac~ turers of the material convert it into finished products. Figure 9 --Rope-Making Machine Figure 10.-broadcloth weaving loom. busy tying broken threads and replacing empty spools with full ones. The occupation involves an e.vpositie to asbestos dust for which the looms iiio hugely responsible. The asbestos doth is usually shipped to firms flint convert it info gaskets, fireproof clothing, and other ptodmls that require a non* BHAKK-BAND UANUKACTUICE The manufacture of brake hands proceeds in several steps, the first being the impiegnnlion of the woven fabric with either an as phaltic compound or a vegetable resin. The Intler is the newer form of treatment and is rapidly supplanting the former. Following this operation a heat treatment is applied in u specially constructed oven. In practice tho ribbon of woven usbestos pusses first into a vat of tho 14 trcuting substances ami (lienee immediately into a bilking oven. These operations me carried on in a building (but is well vciililuted and which is removed from oilier structures sullicienlly to icduco the tire hazard. The treated asbestos fuhiic is now calendered into uniform width and thickness and one surface is ground smooth. The brake-band material is next cut into suitable lengths und holes drilled into them according to pattern. Finally, the linisbed brake bands are branded and packed for the market. In some plants molded brake bands arc made of asbestos yum und British Practice (Cspltsl letter* ployed to denote processes that are oot in use in the American plants In volved in this stud/.) FLOW SHEET Raa cotton cleaned in opeuer and picks. converted into roll of felt known *f "laps" r American practice cotton added St this point followed by picker mixing Crude Asbestos I Crusher I MIXER 4 MAGNETIC SEPARATOR 4 SHAKER SCREENS (ROTARY THREE COMPARTMENT SCREENS) 4 FEEDER BOX 4 Will mti (BRITLit LMJUjI VERTICAL WILLOWtR KNOWN AS A CREIGHTON OPENER) l Screening (SIEVING - BRITISH TERMINOLOGY) Stock Bios ------ --------------------- Carding Machines -a -- -- - - 1 l Roving 1 Remainder of floe sheet similar to that for American practice. Figure 12 -Flow Sheet of British Phaciice. a synthetic resin. The process consists of passing asbestos thread through a built of resinous material ami immediately winding il upon a spool or (Cylinder. Knoiigh of the resin will adlieie to (lie asbestos to form a inutiix into uliieh (be asbestos tliicud will be imbedded. When the de.died tbiekness is obtained, the spool or cylinder is given a lieut tiealmeiil which liuidens the resin. 'Die baked cylinder of nnileiial is removed fiom (lie spool and rut into mmo\v seelions. 'I Iin circular Imnds thus foinied are ground, mm billed, mid otherwise made leady for the. market. 15 `The grindin ; a m faring of the brake hands produces considerable dust. In (tie plants studied exhaust ventilation was used to control the exposure. BRITISH MANUPACTimiNU METHODS British practice diUcrs in niuiiy respects from American practice. The same type of machinery is used in both countries but iu British factories, dust-control equipment seems to tie more generally used than in American factories. British factories specialize in the produc tion of fine yarn and Ibis involves numerous dilfercnccs in practice. hi Knglaud the processing of (bo asbestos begins, as it does in the United States, with the crushing of the ore, lint when this operation bus been completed the manufacturing process docs not parallel American practice until tho liber lias been curded und is ready for spinning into yarn. (See fig 12.) After crushing, various grades of asbestos arc blended iu a machine quite similar to the conventional typo of rotary concrete mixer. It is of passing interest to note that the same device is used for blending tea. The blend of asbestos is passed through a magnetic separator where certain mineral impurities are removed. It is cleaned further on rotary shaker screens where some grit and fiber fragments uro eliminated. After screening, tho material is fed into a widower. The British employ a vertical widower that is known as a Creighton opener. Its action is similar to that of the American widower, und (be internal revolving mechanism is retained.' The widowed inatcriul is subjected to a linn! cleaning on u second set of screens; such an operation is termed "sieving." Widowing is Hie lust of the cleaning processes, after which the asbestos is pluced into bins und is thereafter known iis stock. It is now fully prepured for carding. The practice at the plants included in this investigation is to add cotton to the asbestos and then subject the combination to a thorough mixing in a picker machine. In Kngland cotton is added to tho asbestos on (bo curding machine, both libers being fed separately into (lie bleaker card. The cotton in ail probability is prepared for the carding operation on a conventional type of combination cotton textile picker machine which open do fibers, cleans llicm, and forms (be material into laps, 'flic latter tin in is applied to the cotton which is foi lin'd into a broad ribbon of felt and then wound into a roll. Knglish curding machines are equipped with a feeding conveyor, or lattice, upon wliicb first tho asbestos and then the cotton are. placed. The asbestos is added from a weighing box that is supported over and near the outside end of the conveyor 'I bis box feeds asbestos iu accordance with a piedclermined ratio of the liber to the cotton. When a certain weight of ushrstns lias acc.iimubitcd in the box, a mechanism opens the bottom and allows the inalcrial lo full upon the V) ^ U.X. n S r-l PSS ZX O n! n*11*! uam i i i, PLAINTIFF'S EXHIBIT 1510(14) l<i lattice. Km titer idoug a roll of cotton (ell rents upon the lattice ami unwinds ns the conveyor moves forward. Thus, asbestos covered with n Inycr of cotton felt is fed into the first machine of the carding unit. The carding operation has ulicndy hern desriihed. The roving produced hy the curding muchines may he converted into yum on either one of llio two muchines, both of which have been discussed. As was pointed out, the ting spinning muehino produces a much finer yum than (he mttio spinning device. Since the Dritish specialize in fine yarn, (he ring spinning frames me used virtually to (he exclusion of (he mule spinner. The preparation of yarn for the market und its conversion into woven produets will not ho discussed 6iueo they are similar to tho processes used in this country. OCCUPATIONAL ANALYSIS AN1> A DESCRIPTION OF THE CHIEF OCCUPATIONS The occupational analysis of the four asbestos plants covered in the present investigation is shown in table i. Table 1.-- Occupational analyst* of worker* in the attben(oa textile Manufacturing industry 17 Table I <L, ^uOtmaf anafytis of t>o>ker in f#ie nsbeiluj textile manufacturing 4 induntry--('tmliimrtl Sut llam (id ttt'llfciiy Niiniln r of worki rs In-- -- -- ---- -- -- ---- I'IhiiI A i'lmit 11 Haul C i'lmit n Tout Winding. Yarn iwckera................ Ctulti weaving; MrMFMF MF MF 14 H6 14 a 13 ( 1(1 i rnkMi'lurvrj......................... IUi|r.................................. Tai* aimI bruk*-baa<J we*vIn* WtDvvd <U|w>................ Weavers (brake band)... Clerk................... .................. a 13 Cord. ru|e, and braid workers Finishing: Orlitilori.................................. 1 Rl 2 1 20 0 12 3 1 a i i 9 13 i V 12 1 ' Oeuertd lulmr: 13 Vardmen........... .................. 2 Tidal................................ i> 14 1 4 Ollloe SniM-rinlondeuU......... Ollwis............................. u* 3 33 Tidal......................... . .. in II 3 1 Oruinl Inlul..................... 110 JX 235 641 25 M 1 32 33 5 31 .........i 2 35 , ft 22 2M 1 Jill 0 a Ml ., Kefevcneo to table 1 shows that a number of men have been listed . ns foremen and second hands. These terms have, been adopted I from the cotton textile industry. They do not always mean full time supervisory duties, as might he presumed; in most cases foremen . 4 ' and second hands are engaged in all the activities of tho department lo which they are aligned. Kurther mention of these occupations * is not made in the brief occupational descriptions which follow. IS J'JIM'AKATION ( riis/i it mu n empty tbe raw u.sbeaibi.-i, cnntuiiird in I00-|mhiii<1 bagu, into the pan of (Im> crusher. They uImi operate Ihe crusher amt remove the u&bcslmi fiber after crushing. ll'illowtrs or opiners hnmilc crunhcil fiber uiui waste roving. The rnishcit ore it* fed into the w Mowing iiiio hiuc by meaua of pitchforka. The willuwetl material in usnnMy lilm u into a h|M-eial bin. 'ihe waste accuiuiilateii by the machine in removed aeveinl times daily liy the uitlnwer. Widowers also ojierate BCrcciui for bepamling course giumilar material (cobs) from the filter. 1'u kennen i iuke up the Asbestos-cotton hutches (piling) according to specifiedlinos und pil)i the material into Ihe feeder hnpj>er ami the picker machine. The piekerme in some plants may liAud truck to s|H-eial l>ins the material which is blown from U ; machines. CAHDINO ("orders ojMride the carding maeiiines and clean them when necessary. Stockmen In mile llm stock prepared by the piekermen. The material is con veyed by hand trucks from the stock bins to the card feeders. , TtnAtm look after tin; stock feeders uml roving jack spools. The latter are removed when full, uml replaced with empty jack spools. The occupations of tender uml carder are in some plants interchangeable. 6CINNINO Mule spinnera operate the unde spinning frames. Itmg spinners operate ring spinning machines. Iltlptrs (bobbin boys) assist tliu mule spinners uml ring spinners Conveying fuM jack spools of rov-iiig to (lie spinners and carrying empty spools back to the cards. They also transport the spun yarn ami uttend to the roving jucka and bobbins whenever required. Himoi.INO, TWINTINU, WINIilNO, AND TlIKATIHU Spoolers tend the spooling machines and handle spools on which the spun yarn is wound. Viusbrj run/ helpers o|>crate machines Ihul twist spun matcriui into heavier and stronger yarn. II imhrs o|H-iu(e yarn winding machines. Tu titers puss yam thiougli speciul compounds (usually predominantly starch) ami wind it on large reels for drying. In brake lining manufacture, treaters handle asphalt and resinous materials with which the product is impregnated. Vum puckers wmp and box finished yarn. cloth anI) talk wkavino Ifrtmtlrliilh weavers operate both dry uml wet wrming looms. Tope weavers operate looms for weaving tape uml brake lining materials. Inspectors untl coUntlirtrs inspect ami cMimine ail woven mateiiul for defects and pasrt tupe and brake bunds through calendering machines to ueliicve desired width and thickness Cutlers attend to the creel lacks on which the wmp thread spools aie mounted. Cop winders opeiate eop wimling muelnnes which uiml threud on metal spindles for use in tin; loom shuttles. Il roei r /ofper* usually attend (it the dr> lug of broadcloth which lias been woven wet. They also handle malerial for fix' ereeh rs ami weuvera. 3!) ALL OTIILIl ('ml, i iowick workers ojairute special cord mid rope-making machines and braiding machines. lhake-lining finishers iuchuh' treaters and dryer men, cuieiulcrera who njieratu calendering machines for Hipiaring uneven edges, grinders who smooth olf uneven surfaces, uml cgllers uml diilleis who cut the finished band to retpnred ircs and drill it for riveting to brake shoes for automobiles und other machines. In the plants studied, these occupations were interchangeable. Central labor includes those occupations uhsociuted with maintenance of equip ment und generation of sleaut. They also include janitors, watchmen, and shipping clerks. Superintendence is concerned with the sujK'rviHion of all;pl tu4ju tivitu-a, HKSULTS Or THIS fc'NOINKEKINO STUDY DUST UT1JDILH In the present study, dust counts were made liy the impinger nictliod (2), using etliyl alcohol und distilled water mixtures containing from 25- to 50-pcrcent uleoliol u9 it collecting lluid. Two sutnpling methods were used for collecting dust for chcmicui analysis. (1) Settled dust samples were colleeled at the breathing level and (2) airsuspended dust wus collected with a small, hand-type, vacuum cleaner lilted with u removable, paper-bag type filter. The latter method is similar to a procedure developed by Hatch (5). (See lig. 1.) In addition to chemical analyses, petrographic analyses wete made on several samples. In order to determine the particle size of asbestos dust, an Owens jet apparatus was employed (2). The samples col lected were measured by menus of a filar micrometer at a magnification of approximately 3,000 diameters (oil immersion)- Photomicrographs were also made of dust obtained by the vucuuni-eleaner device de scribed above. NATUUB OP TUB UUHT IUIIN0 IN ASSKsTOS TLXTII.L LACTOUILH Composition.--Table 2 shows (ho results of chemical analysis of settled dust samples obtained by l.bc llaleli method (5). Kxainiiiutiou of these tables does not icveal significant dillcicnccs among the various samples.'* It will he noted, with one or (wo exceptions, that the total ash (no water of crysl dp/,,11 ,ui present) does not vary greatly. The value of 5*3.5 obtained . >, \ l eaving (sample 8) is due to tin; moisture (onteiit of the dust sample. ('alcuiutions of composition on mi ash basis bring the values into closer agreement limn indicated in either table The results given for sample 11 in table 2 are for brake lining which has been impregnated with resinous compounds. 1 L'uiia-lliKi usU-sIm* (i f yMtl<Ii ), ihe ihIm'Uih In llitsv fitrluihi*. Ims ihe lull..* lug cuicii<blllnii Ash. Y3 7u. MiOi, 10 4U, 11)0*. I 17. MgO, O II; ri-iOt, 2 5J |n<hi-iiI (A-.lmUu', V>! 3, No 7, Jmitnxy lu.'i) piii i 4 !I ; : *"=**sSe* if i == ~ ' ! -.*S*-SS.4 ' WcssrsifSiyS .1 . ss -- -- -- r. -- Si I ??? ??? ? 5 = i-Si? 5 tif.i ill M' Figure 13 --Gross appearance op Suspended Dust collected with vacuum Cleaner device (Sec Figure 1 ) ; PLAINTIFF'S ( EXHIBIT | 1510(16) samples, on the other hand, arc bulky, the dill'ncnee probably being due lo (he presence ol long asbestos and cotton libers in these samples, ('aiding and prepaiatioii samples eontain cobs whirl) are present in the raw asbestos. The daiker appearanee of the samples shown in the top row of (igure III is dillieull to explain. It is probably due to the IT? iU'V \ * ^ j ')7vi21^vA? ; PREPARATION 03 Vmitvle si:> -The measurement of dust particles suspended hi the air of ashr ' r plants is dillieull because of the presence of both asbestos nod rottou fibers. 'Ihe differentiation of these fibers miller the microscope is not always possible, especially when (lie litM'is are short and line. Several samples obtained with the Owens jet apparatus were examined with a petrographic microscope in order (o estimate the proportion of ushestos and cotton libers, hut no satis factory technique could he developed for this purpose. In this study, particle size determinations based on Owens jet samples were mude by three methods: (I) euscope projection device; (2) a lilar micrometer nttnchiiicut to it microscope (using oil immersion, 1,000 '), and (li) by means of photomicrographs. Data obtained witli the cuscnpe showing the percentage of fibers (irrespective of whether they are cotton or asbestos) are presented in table 4. These are bused on Owens samples and not on impinger samples. Willi icgurd lo the selectivity of Ihe device used, little information can he given, although it is known (hut for discrete particles, the selectivity of the Owens apparatus and the impinger are the same (2). Taiii.e 4. --1{tintion 0/ fibers to particles in various Ouens jet samples j| II r RING SPINNING TWISTING WET WEAVING Figure 14 Microscopic Appearance of Suspended Dusr Collected With Vacuum Cleaneh Device. 200X. eontact of the spun asbestos-cotton mixture with oily metal surfaces. The microscopic appearanee of the vaeiiuni cleaner samples is illustrated in figure 14. The presence of both cotton and ushesioa libers and >f small pailiculutc matter is leadily noted. The dust from the nirdi. g room is most striking. It Inis few fibers and it has considcrai le paiticulale matter. rout a. The results given in table 4 indicate (hat weavers are exposed to (he highest percentage of libers. This is to lie expected because llie warp threads fray as the shuttle crosses them. Samples collected near the pickers and carders have fewer libers, while the dusts to which cnisheinicii are exposed have the least proportion of fillers. The relatively low pci > >d' of libers iu suspended dust explains ihe small number of hl-m erved while making dust counts of impinger samples. The latter were usually diluted to give 20 to .r>0 particles per quarter field. Hence, except for Weaver's samples in which consideiahlc libers were observed, fibers are only rarely found in making counts of other samples. (Dust counts included both lihrous and iioufihious particles, irrespective of size.) Table 5 illustrates the size range of particulate matter. Two hundred particles in each sample have been measured by means of the 4:1 ia-:itt--:* 24 film mi rometcr. As may be seen. Ilia median size varies from 1.22 miiroii. (o twice this value. Pulton and his coworkers used an electro) ulic precipitator to collect dust samples and calculated an average value for the tidal distiihiition of fibrous and nonlihrous of l.Iilt un ions (4). The median size for particles less than 5 microns, as dedi 'ed from data given by these investigators, is approximately 0 47 in'crons, which is much lower than the values given in table f> of this report. This difference ran prohahly he attributed largely to the type of sampling deviees used in (he two investigations. Taui.k 5 -.Size fttqinnty <iaUibi/fmn of junlieutate dust suspended in the air uf asbestos textile plants Nature ol |in*vs lu re was takro l`l> tV)|falll>lt ......... Chilling Milk' sjiiniiiiiK .. I woiimk . . Wrm in* (l.romldoO ) Wmvln* (tn|*')........... In determining the length of fibers present in Owens samples, photoinierographs were used. It was necessary to use this method of measurement because of the curvature and niutling of libers in the microscopic held, 'ibis dillicidty was overcome hy using compass pointers and measuring each liber visible across a given section of tho photomicrograph. The size distiihtiliou of fibers, classified by occu pation, is presented in table (i. The fibers lango from as little as 2 microns (lf>0X magnification) to as high as 100 microns. The median sizes, as may he seen hy reference to the table, range from 7 to 10 It. Pulton's data indicates (assuming all particles greater than 0 microns to he libels) a median size of 10 microns. Taui.I'. (i -- M*<{<un (inpdi i/ jii<T8 anuiplul tvilh an Owtns jit uppurntits AiUviiy 1. m:lli <>l tllK ri in mil roii'- - ------------------------------------ ........... Wiilowm*.............................. ...........1`nkint; ........................... Twi'nnu U In* (linni.lliMiinl 7 <l M HH 1.' H at i ------------- .... --______________________ ___ No size ficijucncy disliihution with tegmd to the width of fibers present in the ail has been made in (his study. However, it has her noted, with few' exceptions, that the width of fibers collec ted by th Owen , *m| |iiratus w'ns less Ilian 0.5 micron. This is in agreement with the Jesuits given hy Pulton, who shows more than 78 pereent of the fibers measured by Ids projection method to bo less than this size. bllvr CONCBNTWAVION IN IWtkfcnKNT occupations ill earlier studies of tho dusty trades carried on hy tho Public Health Service, determinations of the average dust concentration have been of greut value (I) in describing tho working environment, (2) in inuking comparisons of tho effectiveness of different methods of dust conlrol, and (II) in relating health condition h lust exposure, in this study 242 iinpinger samples were taken urn! counted, und tho results Imve been classified by occupation in tables 8 to 18. Euch of the occupations carried on in usbestos textile factories has been dis cussed separately in tho following section and data for tho ontiro industry have boon brought together in table 19. in this industry there are relatively few occupations in which workers do two or more kinds of work which expose them to totally different dust concentra tions. in such cases tho several exposures have bccu weighted ac cording to tho average time of exposure. Por example, in plant A, widowers are engaged in tho following activities: widowing, 5 hours; picking, 1}* bourn; storage-room woik, hours. These activities are associated with exposures of 2.If, 39 II, and lb.4 millions of particles per cubic foot, respectively. Hence, wo may tahiiluto exposures n9 follows and calculate a weighted uverage; TaIii.k 7---bust exposure of unllower, plant A Activity Tlllir of oiiH.Miro (Inmrs |wr iluy) A vtfiipHlnst iiiiosiirit (Mirorj b MilU.in% of |<<if lirkIiiiiim |h r cubic fiMil xt Willow m*.................................... l`n kn*.............., ................... StoiHKr room work.......... Tolul............................... & 1*! Iti N -j i Jfl ] Id 4 111 il < 21 ` wn b On II million |>urhl' lion K !* . I i i J million s | r * uMc loot The uverage dust count of (be 19 samples in the above table, ciilm- lated without regard to the duration of exposure, would he 18.7 million pat tides per cubic foot. I'rtjHtratioH'-- Pieparation includes the occupations of rrushcnnrn, willowcis, and pickc-imen. In plant it, these lluee occupations were conducted in the same room, while in plant A only crushers mid wil- * lowers worked together. Picking (including piling), in the latter plant, was done in a separate room. Tho dust exposuiea arc indi cated in table 8. ui; 27 o Taui.K 8 -- Ihi at exposure of woiktm in the prcpaialion department i. The exposure of workers in carding rooms is given in table 9. NiiiiiIht ( l>nl ft.mvn Mllllplus (rnti..n Ittk.i) (M rirn Cruslirriik'ii ..................... Will.,*. (* ..................... i`ii kmiivii 1....................... V 2 : II 5 II I J41 0 ill 31 3 74 3 1 'i > i J t)uat expoaure. of workers in canting department Ou:ii|Nillim N2.iHtiam11k1e|l**In*r*Sill (c1MtI'lilisMlr!.i'KltiK.inll-)i Weighted aM-iagc. It will he noted in table 8 that the crushcmicu's exposure is relatively low. In tho plants studied, this work was curried on near an open .CH.at.ur.cd.kem.rs.e.nn.n1d..le.m..l.e...ri..... . ---3I-HI -- 1 Weighted average. 22U2 1 door. However, it is doubtful that this occupation generates the The average dust concentrations in bulb plants A and B were quantity of dust shown in the above table. It is more than likely that similar. Counts as low as 0.4 million particles pm < uhic foot were willowing and picking (and even carding) contribute to tho dust ex obtained for some carding operations where machines were operated posure of crusheniien. at a relatively low speed find us high as 139 million purticlcs for high Widowing of crushed asbestos is not in itself productive of much dust speed operations. (11.1 million particles per cubic foot). Only when waste roving and (ly In the two plants studied which curded ushcsios-cotton mixtures, fro in cyclone collectors are willowed docs tin; dust count increase. 1 >ust all equipment was hooded and exhausted. Under the methods of counts as high as id) million particles per cubic foot have been obtained operation, which required accessibility to the machines, complete with lly. A continuous source of dust production results from the enclosure was impossible. Consequently, exposed brushes, revolving manner ir. which widowing machines are fed. Thu material to be at high speeds, often nullified the effect of tho control system. Nor u illowcd is raised waist high by pitchfork, causing considerable spilling. could air flows in the exhaust system he increased since a considerable Widowers also operate shaker screens. umoiint of vuluable fiber would be drawn from the brushes ami this A picket iiiun performs several kinds of wink. This is especially would reduce the weight of roving to an undesirable extent. tme in plant 11,^ where piekermen not only assist in piling (mixing Spinning.-- Both mule spinners and ring spinners urc exposed to of cotton and asbestos), but also uid in stacking the material blown similur dust concentrations. The range shown in the following table from the picker maebinu into storage bins. This last-mentioned (table 10) for each occupation is probably due to the presence of more activity ] iodines dust concentrations tanging ns high as 211 million spinning und weaving equipment where the dust concentration is particles >cr cubic foot. Tickerincu usually work in pairs and alter higher. nate in fi citing the picker mucliiuo uud tending to the storage bins. Tiling is (.one by both workers together und contributes to dust counts Taui.k 10.--Dust exposure of workers in mute- and ring-spinning departments averaging I f 2 million purticlcs. Ticker machines, like widowers, aro fed by pitchfork, n method which produces undesirahlc dust. 'This is true even where picker ma Occupation Numlier ol Dust cun- Minpta tietitreliuti laksn (MPPCF) chines have hooded feeder boxes. Tho picker machines studied were equipped with oil sprays, pre sumably to bold down dust. The ineirectiveness of this method of dost control is .shown by the dust counts which exceed 50 million par ticles per cubic foot of air. Carding.--Tho brushing and coiuhing of asbestos and cotton fiber mixtures by carding niuchines creates considerable dust. The carding action is such that small cobs and Jine talc adherent to the asbestos liber are thrown into the air. This effect is accentuated by the fan action of the brushes, 't he grnmdur and nonlibions appear ance of the dust present in the air of carding rooms lias been shown in figure 10. Mule spinning . . . . IS ..... . . .King spinning....................... 12 ......................... ..... _________ -- mil ---- -3 2-g 3 .. Mole-spinning opem I1' >1/ mire considerable space and are gener ally separated from olh< > h- lies. On the other hand, ring spinning is done in close proximity to spooling and twisting and it is possible that the dust counts arc influenced by these operations. The results obtained for mule spinning cheek with those given by Fulton und his eowoikers (4). Spooling, twisting, and winding. -- The equipment for these opera tions is geneiully grouped together and theicfoie it is dilliciilt to obtain u clear-cut estimate of the amount of dust produced by each. I L'8 The average range of (hist concentrations in plan(s A urui U are shown in the accompanying table (table tl). Taiji t 11 - butt iifinsurf of u'ortrrs 01 ijitm/trip, (tWsfinp, amt ii'i>n(iM0 tftjunf mcrita o< UlM'olt HfHX'llTS . T**i>urs mi'l linljH-rs Daivtrxul wIihIuC* . Nnt)il>vr taken lltlvl mil i fulfill lull tM itch Ot WI|MUlUI NiiiiiIh'i Snlh|lt* taken (tH'r-('tlrcitiimiii-i (MITCH 3 JIJ 1 Hot mg w imiffs .. . J) 3 2 U 2 \ urn (mii lifts.................. A 1 Ml 0 Writ Ifenltrrs... . 1 a& 2 ii 3 I 7-3 <1 Of the occupulimin listed iii (lie table, twisting tiji|i<>ni<-<) In cmi- (ill>11(e must uf tlm dust in |>lmil It ml In inllncncc dio exposure of spoolers noil ring spinners close by. Twisting freipieutly proilueeil euucciit rut inns of over 20 million pnrlieles per cubic foot ol sir, yet cnitnls hclnw 10 million piirtic.lcs were not iincoiiiinon. Twisting involves u eonsiilernble uinoiint of fraying anil wlien low-grudt materials are uscil, the <1 list production is increased. Winders and yarn packers are exposed to lower dust concentra tions than spoolers and twisters. Here again, however, hcruuso of the proximity of the latter dust-produciug occupations, the amount of dust actually gciicrnlcd cannot he estimated. It is loud to con ceive of such operations as roving winding and yarn packing producing much dust. * itiiHiihlntli HHarnuj. Tim dust creuted during tho weaving of broadcloth depends upon tho number of warp threads per unit of width, the ipialily ami width of the inutcriul woven, and on whether the operations ure conducted dry or wet. If the warp threads are close, the fraying action which lubes place during weaving produces a considerable amount of dust. With some looms the dust coneen- tiulinn was found to exceed HO million particles per cubic, foot. Average dust counts obtained during weaving operations are shown ill tuhlu 12. 10 h11. I 3 -- /lust espoaitrt uf workere aaaociated with broadcluth U'Uii'otp OtuiHujlIon t *rit ful Inn taken (MITCH Weaver* Hint lifl|*fs Ory................................... t nrili-i* Hint tut| r .... 7 4 7 II 1 Iriviifi Infi Hint rulemlerer* .. . 3 3 HI a ------< ( wiii'ltrs.......................... 3 - 0 --------------- ------------------------ --- -- - Weaving ope utinus ure intermittent owing to freipient hreakago of wuip thread.. Conscipienlly, wmkers ure exposed to iillcrnntc 2!) periods of high noil low dust coneenlration. On Iho other hand, weavers must p,, , .*! . attention to work and are subjected to heavy exposures while the looms ure in operalion. The dust counts shown in table 12 for weavers and helpers illus trate the diirerene.es between diy and wet weaving. Iloth dry und wet weaving uru carried out on similar looms in close proximity. However, operators ure inlcrchangeiihle und are not Hpecilically designated as dry or wet weavers. Under such conditions, it is im possible to gauge the ue.luul exposure of a weaver. The low count of 1.7 million purlicles per cubic foot given in table 12 for both dry and wet weaving is for a small plant with one dry and on* wet loom in operation side by side. Tho higher counts are for a linger plant manufacturing ull types ol broadcloth und ut tho time of tho survey having from 8 to 12 looms in operation. In view of tho high counts obtuined during broadcloth weaving, it would he expected (but creelers ure exposed to comparable concentra tions. That this is not the case, however, is indicated in tuhlo 12. With all looms in operation, us is freipienlly the case, the counts might conceivably be higher. The same is also (rue of inspectors, caleuderers, and cop winders who work in the weaving department. These occupations do not produce large amounts of dust. Tape, icirfc, naif tratc-fiuad uusmiai).--The dust exposures for tape, wick, and hrake-band weavers are indicated in tuhlo 13. Table 13.--Uuat ei)n,mrt uf workert uaauciated with tupe, wick, and brake-band weaving Ntimlief uf Oust run sampli's uiMtratinii takcu (M ITCK) Weavers (U|ie anil wick).. Weavers (brake IhiiiiI).. . <'ttlcniU'rcr* ......................... >2 14 3 1 24 A 1 It may be seen from thin tuhlo (hut tape, wick, und brake-lining weuvexs lira uxpiiHiul to lower dust concentrations tbun broadcloth weavers. l<'xcopting certain t\pcs of brake bands, the fraying of the warp threads during weaving " ' as great as in broadcloth weaving. However, with heavy brake hui. . such as are used on trucks and hoisting machinery, tho dust concentrations become high und com parable to those obtained in broadcloth weaving. It is in tho manu facture of such brake bauds that creelers are exposed to counts of 20.li millions of purticlcs per cubic foot of air. (Vlendcrors, being at some distance from tho looms, have u low exposure. 'I he dust counts obtained for the type of weaving here discussed were consistent in all four plants studied. A\) (\>nlt topi', amt braid working.--Other activities found in tlio nshcstos tcxth ^ plants air concerned witli Ilia imiuiifnrliiic of special products, son as cord, rope, ami braid, and in ircnting and finishing yam. These. operations produce little dust as may lie seen by reference to I Ida M. Taui.c 14 - Dust exposure oj workers manufacturing unit finishing special products Oll'll|UlltMI Niimlx r of Ollsl (II- MUMph'd <i iiI(hDiiii IhU'U (MITCH Cord, i|M , ntiU hrNiil worker* Yrii inHlirs . .. M 3 1 7 3 II TIil' equipment used in manufacturing these products dues nut operate continuously. Nunc uf tlic operations of curd making, rupo making, or braiding requires fidl-liinc personnel, imd small group of wui krrs pci fill 111 nil (licsc jobs. Tlio highest dust count (10.2) in tiililo Id is fur braiding. The counts olitiiiucd for yum treaters are iidliiciiccd by (lie upcnitiuns undertaken nearby. lirake-baud finishing. Tliis generates little dust. In the plants studied, finishing operations weru conducted in separate rooms or buildings. Dust counts are shown in table 15. Taiilc t5.--/lull eijwture of uuiOil nnmnfncluring finiahal brake-ban,l lining Occupation Tivutr ts tvittl <UU-is. Cnkittit-n rs............... Orimk-rtt.................... NiiiiiIh ( Ihixl ionnf X|tlll|>ll`X 11111(1111011 Ink til (M TI'CK) (kcii|wdoit \ 1 ft (*ulli'M and tlrllh rx 1 1. & llnuiik-ra..................... 1 4 2 ('olkra......................... NtiitiUt Oust enu- of sample (itki-n (viilrulloli <m tcch i ta > I6 i i ft Workers employed in tlio occupations listed in this table are exposed t `lust which dilfeis in composition from the dust found elsewhere in asbestos textile plants. This is because tlio dust generated by guilders, cutters, and drillers of treated stuck is made up of resin, /isplndlum, asbestos, and metal. (See analytical results fur sumplu II, table 2.) Miscellaneous occupations. Ill addition to the groups directly concerned with the iniimifartiiro of textiles, a considerable number uf workers (engineers, general laborers, clerks, and superintendents) are engaged in oilier activities. Willi the exception of certain foremen, these workers uro exposed to low dust concentrations. The data presented in table Iti require no rommeiit. .11 Tmp, 1ft.--Dust exposure oj miaccltnmoua groups Occupation KiigtintTS......... j l.nlwifrrJ................. Wnlftimon........... Shipping clerks .. 'hihIhT of Hlllllph'ft iukt-ll Dint ton i.nU.iD.m (M TI'('K) Occii(mlioii NuimIht vl Ivlilnl.tlniluii.lnl- IbIm`11 (Ml'l'l K) 0 10 C>2 3n ft ll(i'lllc'll (plaid)...................... <> 1 1.2 HiiirrHilululciiti (idllcc).. 2 . 12 1 . 12 Clfrki..................................... . 12 Rumples anti nt(waiin dciwiiii un It* cllvltki willi wlilcli Clrcy are m-wcIbUhI. PREVIOUS IHI8T EXPOSURE Tlio dust concentrations discussed in I lie preceding pnntgniplis represent present-duy conditions. TIo olliehils of asbestos textile plants have in recent years attempted to control tlio dust liu/.nrd. In the plants studied, cHarts have been Hindu to exhaust picking, carding, and brake-band grinding machines. (Another plant, which will lie discusscd later, lias extended the use of control cipiipmcnt to nearly uvery dusty operation concerned with the mumifactiire of asbestos textiles.) A knowledge of the exposure of workers prior to the introduction of control equipment is important in correlating clinical findings with dust exposure. In order to cstimnto pust exposure, the air How through vnrioim hoods uttnelicd to carding machines in plunt A was shut olf for 2 hours. Dust was allowed to accumulate fur I hour prior to sampling. The dust thus generated caused much inconvenience to employees in the course of their work. For this reason, permission to shut ulf exhaust ecpii|Uncnt was not grunted in other plants studied. Carding iniirliines are sensitive to slight air movements and are consequently dillirult to regulate. Once they have been adjusted, any external disturbance alfce.ls the weight of tlio roving produced. The dust counts obtained under conditions simulating tlioso prior to the installation uf tlio exhaust system are shown in table 17. Fur contrast, present exposures nro included. Taui.e 17.-- Dust counts when control measures are used and when they are not in use Occupation A t rrngo lljst roiiiii Him . o V1 IMP 1 Cft) Occupation Atting* dml cmiiit - imVtch |>Hs( .on- Cd`uHnUU- |iri -a III ('nislicrmfn.......................... Widowers............................. I'll kennen............................ (`anlert................................... M) 2 Ml 2 A.I 0 72 3 23 II 1 31 3 W1 Mule ipiuwrs .................... Mint; *|iiiiiioi* Iw l/dcrs, s|MHih t. uiot winders .. W.avi-rj.................................. 1ft ft 3V 74 32 47 Tlio low (`minis obtained for tlio occupations listed below curdcrs is duo to u partition which separates them from tlio curding machines. Mule tqiinurrs nix: lorali'd iniiurilmli'ly bryoud this puTlitum, uutl llu: ilu.sl rouiit shown is due to dual wliieli lies passed through an open diair. Tinea dust samples olilained in llu: nmling riiuin I Imur after the e.xliaust fans were slmt ulf gave eiiunls of 77, 7:1, and 78 inilliou puriirlcs per eultie fool. At flu: end of 2 hours a sample taken in the same room gave a fount of (il million parlieles. No major ilmngas have hern made in plants C and I) sinee the start of operations. The dust counts made are essentially the same us those which have always esisted. On the other hand, no data are avuilahlo for past exposures in plant II. This failure call ho littiihutcd to several factors, hut principally to the gradual expansion of the plant with the growth of the industry, which increased the amount of equipment, ami the changes made in recent years with tho exhaust system. Tho first of these factors appears to have utTcrLcd all operations conducted in the plant, while the latter is restricted to the carding and preparation departments. In addition, it may hu pointed out t at plant expansion has tended to increase dust produc tivity, while the introduction of exhaust systems has reduced it. Hence, it may he assumed that the exposures of all occupations ill plant K fulh. ving carding were prohahly higher during the. study than prior It expansion. It must ulso he iumwI.......I that more men huve la" n working since the introduction of added equipment than at previt us limes. in i MtriimTloN or inisr counts The average cl list coneentralions just discussed make a satisfactory mcasine of dust exposure, for most purposes. In cm relating medical findings with dust exposure, however, it is frequently ndvaiilageoiis to express the dust exposure in units which comhine duration of exposure with average dust concentration. An easily ndcidaletl dcsciiptivc value was developed during statistical analysis of tho insults of an engineering and medical study of anlhraeo-silicosis (51). If a worker's dust exposure has heen unchanged for all practical purposes during his period of employment the aveiage dust count (in million particles per cubic foot) is multiplied hy the duration of exposure in years. The product is used as a nil rieal sine of his total dust exposuie If a worker has changed his uceopiilion (ami in so doing has changed his dust exposure appreciahly) a calculation such as the one shown in table 18 is made. 3.1 Txute 18.- / r i allowing Ihc inrlliud of computing the limit eipoturc of aabeatoi 4 Uitile workci a 1 --------- ------------- - ---------- -- - llttti|Hillu ul worker Niimlwr of year* In (Ktitiiaiinii Million* ol lu->l IHMIll jMtrtitle years (M m:K) j.t r cul>ie foul of air Cartier ........... Canter . . Mule 8|Miiuer. ... ... `a 72 3 7 2V 1 2 2A 216 U Ml 2 62 Tolol....................... _________________ _______ -- 7 2M> 3 ------------------ ----------- -- . --........ .............. 1 I'lnnl A. 1 1`ilof to Installullo" of cifmua ty*li' W.ICM.J dan ....... , culile Tlic worker wliowc limit exposure litui calculated in tablo 18 would lc aabitfticd a value of 280 million parliclc-ycura in laliulutioua In which, for the aaku of simplicity, it wan dcairahlu to have a one-term meumtre of duut exposure; tuhlc 42, for example. When average dual concentration and duration of expotmre ure to he tubulated beparately, aa in laldc 43, the individual described in table |8 would I>e assigned a dust concentration of 40 million particles jh.t cubic foot. TIIE CONTAIN. Of ASU1&TO* OUST The control of dust in iiuliaatiy often entails ninny practical dillicullies. Those difficulties pertain chiefly to Ihc handicaps imposed ly control equipment upon the performance of the work being Join*, iiml in estimating it priori the air volumes required. lloth of these difficulties are inherent in tho usheslos industry. The arrangement necessary /or removing dust from earrling marhines umj from looms, which demand aeeessihility to all parts, is self-evident. Added to this icquimncht is the limited information available with regard to suitable design of equipment for each dust-producing souree amt tho requisite air vulmnvs. Tho latter item is must important in tho design of hoods for carding machines, inasmuch as air velocities must be kept lelatively low in order to prc.ve.nt the. ushestos-cottou mixtures from being subjected to air eiinenls which convey them to the exhaust system. At the same time, however, the velocities chosen must ho adequate to maintain the dust helow the safe or threshold limit Tin* dust-control data contained in tho following paiagraphs are based on observations n> i <* iwo plants included in the present study and on data obtained . . owlicic by Assistant Public Health Kngiiiccr Kichurd Pago (7). The data presented include operations for which control methods have been developed. In addition, the type of control equipment used in Kiighmd is discussed, ullhough no values pertaining to air requirements are available in this instance. MlUI'Alt AITON l>UI`AH I'MUN I The dust counts presented earlier in this bulletin for the preparation department apply to uncontrolled conditions. A very high degree li u of ronlrol c/m, Imucvcr, Imj effected under rerlin comlif ions, espei-itilly ns regards widowing (opening), piling operations, and picking. The crushing machines in the plants studied were not exhausted nr scgregatei|. In ICngland, on the oilier hand, il is customary to encioso iiinl segregate crushing equipment while it is in opemtion. U iitowiny (opaiing).-- Widowing machines me often productive of Ini'll dust concentrations (30 MPIT'K). As has been previously mentioned, Ibis dust is cmised both by the nmiiuid methods used in feeding these machines mid by the notion of the machines thcmsches. Consequently, u reduction of dust concentration may be obtained by using a conveyor feeder which eliminates raising materials to waist 35 Piling.--Piling operations are usually conduetcd close* to picking machines IV -lust, generated by this operation may bo effectively controlled by u .mg small exhausted compartments or bins. Compart ments constructed as shown in figure 15 and handling approximately 1,025 ('KM of air reduce the dust concentration from an average of 20 to 5.1 MPPOK. Knglisli practice in piling consists in using exhaust manifolds close to the mixture being made (lig. Hi). Air volumes arc not uvuiluhlo for the type of exhaust shown in the figure. The method uppears to bo cumbersome and to interfere with the process being carried on. Picking.--The exhaust control used on picker machines is purtly Figure 5 --Exhausted piling Bins levels with forks and using un exhaust above (bo feeder box and below the ninehine bousing. The wiliowed material should, of course, be pnciiiiuili ally conveyed to u suitable bin which is Ncgregutcd from the preparation room. in the case of two machines equipped with exhaust, it was found possible to reduce dust concentrations to 3 li MITCK. The exhaust hoods located above the feeders drew 400 ('I'M, while the downward exhaust i-clow the uillowei bousing drew amounts of air ranging from 225 (-K/V. to 000 ('KM, the latter air /low being used on u lly widower. (Seo lig. I ) The air bundled by Iho pneumatic, conveyor was 1,800 (KM. "or the 11-inch diamclcr duels used, this corresponds to an uir veloc.ty of 2,730 feet per minute. Figure 16.--Exhaust ventilator used for Piling operations (British Practice). shown in Iigtire 17. One hood is connected at the feeder and ami ono Hi the tlischargu end. The renter portion of the. picker is also exhausted (not shown in (i|*nro). With this typo of arrangement the dost con centration averages U Mn't'K. Tliis value is roasiilerahly lower than found nmont* ........ led equipment, which exceeds in ninny instances 71 Ml'l'OK. It was found that hoods above the feeder handled filll) ('KM; the downward exhaust at the center measured 1,020 ('KM; at the discharge mid the air How was 450 t'KM. I'ncunintie conveyors nllaeheil to tho discharge end of Home of Iho pickers handled 2,000 (!KM. These duels were npproxi.....tely 12 inches in diameter, thus providing for n conveying velocity of 2,550 feet per minute. d7 II is :ui:v,ilili' mill .s|irrin| riiiivr\nr lull-, >|M-rn I ini; liclurcii Hie ll^liisloi,.( ,,|I(||| ,1,1.1 ||,,. Irnlri inivcr llml 11,,- ,|u-.l ,iii-<-ii I rn t j, ho i educed hrlow the \ nine nf 0.4 M | * I *< 'h\ itii lien | i*i | r. CAIOlINO noar (hr r,>()|or of tho maohino. d ho oponin^s d,J mid /' aro looatod ill the 1 '* ' of tho oards and exhaust Iho hotlom fly w hicli acciimuhilos. I Itr air volumes exhausted hy each opening mo imlioutcd in the limine. J11 addition to careful enclosure of the machine propel in (ho second typo of system used, the feed ho\ is carefully covered. Two typos of ilosl-ruuhnl equipment me til present used oil rindin'' machines. The fn.j ly pe eoiisists of it ImioiI which is located ilirrrlly nhovo tin* ex posed brushes of llm ninrliine (litf. IK), while the seeond (y Figijrc 17 - Sghkmafic Drawing of LxHAusr SvsitM usto With Picker MACHINE ih t <(111 ly enelosed nml ex hausted til various points (li^. r>). Studios made of tIn; first lypr of exhaust systems showed 11 mlnrlion in dust ooiierutialion ranging from 72..'i MKMl'h' when no ventilation whs applied to 20.1 with ventilation. 'flic nir How for nirli I1001I averaged K70 Oh'M( which corrrspomlnl lo .six nit chant'es pn- hour in the room in w 11 ill 1 thrcmds were located. It may licsmi I hat the typo of hood and tlm air (low used inlinr the dost eoiierntratn>n to approximately onr- ihiid llm amomil created without, vnililation. The second typo of ex haust system nsotl proved moir cUcctive than Iho lirsl in lodm in^ du(ino-.s. Tho dost oomonlralion dctciminod from Jimiicroussmnplcs landed fioni I to ;p.i million particles pel cubic foot. 'I'his hijji decree of dust 1 on 10\ al w as accomplished with an anun^cmcnt mmhu to that, indioalod ill li^nios Ml and JO. In tho piimaiy FIGURE 18 Vt'NIICAL EXMAUSI VtNIILAIION Ann.ito ioaniihi NOi.ost o Primary Caroinc Machine oard, hou.ls <1 and A dtschm^e upwind. Tito dncl r exhausts from (ho ladtonl of the rill'd. Tho sccoudaiy or roving raid is lioodod 111 r Figure 19.~ Totally Enclosed Exhausted Primary Carding machine. The design of 1111 oxhausf system for carding machines is rendered exceedingly dillieiill owing lo Ihe ease with which, curding material loaves (he rolls. Hit'll **' Nows may seriously idled Iho |mility of the loving produced. Likewise, a poorly const moled housing may create eddy currents which may prove hothcrsonic. Any system dov eloped mpiircs care ami c.xpcrimeiil in design. M-IHM.INU ANII I'W 1 > I l\(. The dust generated hy spool <jt 1*0:1 II 1 11 VV 1 i< t`r t i i'i LI. <d m u ri 1 wUly clJ.l-t.i to Figure zo ti lvaiion anl> Plan for Sconcing Exhausi Sysiim ing operations may la* ingen iously controlled hy a system id cones in which the spools mo insetted and exhausted. Snell a system is shown in lignin 21. Kneli case is const 1 tided so as to oiler a minimum amount of interference to the wink being done. In the ease of four hosier winders (2011 spools) eaeli rone is 0 im lies in diameter aeioss its widest pint mid 2 inches at the duet connection. 'Ihe roues an*, eaeli It) inches deep. Two hundred emu's were found to handle an I :(K I aggregate of 11,27(1 ('EM or mi average of 40.fi (I'M per coni' Tim dust concentration mvcin^cd 2 !) M1TCE. Without llie cone system discussed above, tho dust concentration fur llie sumc o|ieniliun was I Kl. I MITCE. Twisting iiiueliiims me mule dillieult tu exhaust locally tlinii spoolcis. Eiguic 22 allows n system wliicli lies heen pill lly euinpleled. It consists of exhausting llie lower section of the twisting uiiirhinc hy extending n duet with openings along the entire length of the equipment. Each system ultiichcd to the nnichinu is intended to Figure 21. Exhausted spooling frame. exhaust 1,(170 OEM. Dust delerminalions to establish the effective ness of this system could not he made owing to the fact that only one of III twisting machines was equipped with exhaust and the counts obtained were nlfecled hy unexhausted machines opeiating close hy. . WEAVING Any system developed for removing dust generated by broad looms represents the accomplishment of one of the most dillieult opeiations encountered in the design of exhaust equipment. Never theless, this has heen done elfeetively both in this country und in England. The American system shown schematically in figures 2d and 21 consists of a downward-draft hood lilting close to the shuttle rack of the loom and a movable upper exhaust hood which operates oil the sill face of the woven malerial. The hitter hood is actuated to and fro hy the action of the loom lay to which it is nllachcd. The hood is connected to (he iiiiiin exhaust duel hy means of a llcxihlo I air light joint. Ilotli the downward ami upward exhaust hoods me .....row I ; J.ess the advantage of high opening velocities. Tho upward ilnili I......I connected to the loom lay is segmented. Each hood used, as indicated in figure 2d, handles 1,200 cubic feet of air per minute and reduces the dust concentration to nil average of <1.7 MITCE. The system is thus extremely effec tive, since on tuicon- ti oiled looms the con centration averages 411.7 and may exceed 140 MI'l'CE. The English method for exhausting looms cl i Iters considerably from American prac tice. In the former system all purts are stationary (lig. 25). The looms are ex hausted upwnrd hy hoods located ill front of the operator ami resting a short dis tance away from the luy. The hood con- sislsof twopurtswhich may he turned hack whenever repairs to the loom lire neces sary. No data ns re gards uir volumes used in this type of equipment or its effectiveness in reducing dust ure available. inspection . . Ju some plunts, a-lies I os cloths are brushed during inspection. The usual proccduu * 1 i ill brushing tho cloth from ubnve and below as it passes over the inspection table. All inspection table of this type with exhaust hoods is shown in liguru 211. Tho hoods used are located near the doth brushes, und extends the full width of the cloth examined. They arc, however, only one-half inch in width. A study made of an inspection luhlo such ns discussed above indicated that two hoods located on either side of the cloth handled approximately 711(1 DEM cucli. A third brush und hood located near 4:1102--aa---- 4 dli Oh* jwk spool uL llu* mil of llio inspection tnhlc linnillcd 102 ('KM. These. hoods reduced the dust Kencmled from n value of 11.1 when no ventilation was applied to it value of 0.,r> MI'J'C'K with ventilation. MUMMAItV or THIS STUIMf ur TIIK WOHKINO fc'NVIWONMtNT The oii^iiirorin^ data <onlnin<><I in (his report are Imscd chiefly oil n sillily of four asbestos plants. Data on dust mntiol methods 41 Dust eoneenlialions wen determined l>y means of (lie iinpiii^er leelinii|Ue !":lit lielil counting. In all, 212 impiugcr sam|iles were taken so as to evaluate lire environment of eaeli occupation. Figure 24 --Detail of Exhausted Loom Shown in Figure 23. Figure 25 --Detail of Exhaust used on British Type Loom. The nuinlier of workers employed, tlio nuinlier of dust samples taken, and (lie dust concentrations determined for eaeli occupation are presented in tnlde 18. Tire concentrations range from values of 0.8(1 'igure 23 --Exhaustto Bhoadcuoth Loom. I*iiVi* licen sit. led ill (lie course of a separate study undertaken in a liflli I>l 111 'l HO of Ilia four |ilaii(s investigated Hero engaged ill till) manufacture of asbestos textiles dirorlly from law crysolilo (< 'aiiiidlan) asl estos received iu Itltlpoimd hags. Tim remaining two |iluiits began i |ioralious Hilli yarn received from oilier sources and were roncerned only willi tlie maniifaclure of aslie.slos, tape, liraid, or brake luiudi ig and willi llieir Irealment. Figure 26.- Exhausted Brushing ano Inspection Table fur shippers to as hit'll ns 71 II MITCK for pickmnen. Occasional .sample* exceeding 1 Oil MKI'l'K wero found for the occupation* of nudiiiK ,l,,d weaving. 42 I aui.l 111--- t tccu fuititnial tlust exposure of workeit in four aslubtoi textile plants Arln Hy ami ut( ii|>uilu workers Number il 1 >tixl i uiueo- lfH(HIM Ink fit <M I'l'Ck) I'd |iiiriilinn < rn>lh him u ' XVlIbiWi rt ......................................... I`i k< nm ii .. . .. (`iir-lrrs Mini ! inters . . Slot l llll'll......................... . S|>iiinliit! M nil' ^iniiin ri un<l It. I| rs limy i^iiiiu r-. mi<| Ih-I|m rs. _. . S|NHlhll|* .''(Mlll'IS .. ,, Twixling Twislt t> uml ln l|H.fi . Wimhm: f < m\r'v>il winder*. .. ... . Il.il Mlt Wimll'fi.......................... Yum i* n l>rri....................................... Yarn limb rs........................... . ('k>ih in iiiy Wi'iiu rs uml Im I| nr. I >r v ..................................... XVi I .... . .. . Ivi*>jn'i Ii.jn mnl riili iiilin ra .. Cii'i l< rs mnl In-11-rs................... ('n|i w iinli-rs............................. , Tapi'. n k. mnl hrukf buml huhviiik XVinuis (|ii|m nml wnk)............... Wriiu rs (brukc-bitml) . . Cm In-................................................ ( 'nli mk (i rs....................................... Coni. ro|i< mill brul<| workers............ . UrnIn lininl ftiiixbing Tn .ili is nml liners..................... Cnli lull'll la.............. . .. . I Dlll.h lS................................................. Cullers uml ilrilk-rs.......................... limmli'rs.............................................. Cullers........................................... .. (li'in r.il l.ilutr. Iiigiums ................... I jiIioii rs (iliip|M fs, ilc )............ XVnii Imii'ii......................................... 8ht|i|>mg dirks........................... Yniiliinii.......................................... OQbv Hi<|m mill mli iili (iritlin)............ fr'nii'im n (iilniit)................ Cbrks..................................... `I tilnl ........................ w V 2aA 3 7 H 'll I JA o V 21 Jl J 74 3 42 30 IK II 2lf 1 22 ft 21 in 2 0 7 ft 2H 13 3 211 22 A 3 2 13 1 4J 20 3 2 13 a >1 3 12 0 0 21 ft 3 IJ 2 12 12 3 17-36 ) 31 ( 1 4 7 4V 7 4 7 111 ft 3 3 A III 3 HI 4 3 II 0 H i e 3 600 31 12 2 4 3 1 H 14 4 7 21 U H 3 2 4 ai 3 1 3A 21 0 1 10 2 J C) ii 1 >i 1 1 Cl 1 <) 13 42 13 13 72 14 2 01 71 2 () A2 TV (`) 40! 243 12 M .1 2 12 . 10 . 12 <) 12 1 l'|-"iin' wi'iehinl in inko min ai immt jiIIiiik. bli nking, uml slumkc I'll) uelivillrs i I in liiili s i|N<siiii' ilni' in n|H ntilnn o| stinker si rveu * A v luge Hi' boles >( In l sum | lies * 1 >n <1 rimnlb oMiiiii. <1 Imiiii s>uo|>b -t nl ulber nccU|tuilotis huvilig similar ilii'l eiiKMurs. 1 l- i|.u>iin s ui rnnlliii: in assoc luh'<1 Millville* Tlifi clumiiriil uml |m!|in^rnpliio. uimlysen of ilust sumplos wore ilotcnnim'ri fimu both hctthul dust uiimplrb nml sample:. obtained direelly from tlie nil l>y means of a vuniiiiii elenner. No great iliffemiecs ill composition wcio nolcil between cm lespoiuling snmplis collected l>y these two methods. Tolal nsli was approximately 77 permit for all I In- samples. No free silica (ipiart/.) could lie found on petrographic analysis. I arliclc bi/.o dclciminafions of Owens jet samples were, made liy tlnec melliods, namely, (I) mill a eiiscope piojcelion device (for defcimmiiig ||ie ratio of filter to parlieulale inaller), (2) liy means of a C! filar inicrone : j (lai liment ton mieroseope (for measuring the size of particulate .... II. iq and (2) with pliolomieiogrnphs (for measuring the length of fillers). This study showed that the ratio of lihcls to particulate matter varied considerably from a maximum of 2ti per cent for weavers to a minimum of I percent for erushermen. The median particle, size (exclusive of fillers) was approximately I S microns. The median liber length vuried front 7 to Iti.tt microns. No distinction could he made between cotton and ushestos fillers. In most of llio plants studied the control of the dust hazard was limited almost entirely to provisions of exhaust systems for the carding machines. Data, however, ale available to indicate the elteeliveness with which the dust problem can he handled in an asbestos textile plant. An elfeelive method employs llio use of hoods and exhaust equipment fitted at each dust-producing source. Data showing the ollcctiveness of exhaust eipiipmeut is presented in table 20. 'I siiI X' -0 .X'i,mmnnj of results showing the exposure of asbestos textile markets under controlsd unit uncontrolled walking conditions K<ii>i|>inuiit Nimtlier Ilf tbit t COIIIK'C- 1 UMIS Volume of sir bnmtlfil (CFM) Oiibl (tin- eeirirut ion wllh fOmiist Ouri tunivtllrulbrii willitMii ea- IfUlHt WtllKwing (oiwnluc)....................... I'llmu *............................... PuLmg .. .............. . ... ('iifilltil' (|rrliiiiiry)........................... ('itnHnif (rovme)............................. - ......................... Wi'itviiif (hruaiHomn) ................. Ilruxber tuloit'lerer......................... 2 02S l.au 1 1,023 a 2, 370 3 1. 420 } 4 >. no * 1 4b 3 2 I.UJ0 3 I.I.SO 3 A II I 5*1 0 20 3 4 6 7 ill 3 74 3 2 0 72 3 2 ft 13 I 7 1.11 4 7 4II0 7) I wlili iMicHmullr conveyor. * Kilirtir.lwt bin nr <iiin|<tultncnl * imllviJiiul time luf ouch spool uuiJ comiecled to eibaust manifold. It is evident from the above (tilde Unit the dust hazard in (he asbestos industry etui he greatly reduced. It is further cleur (hut the necessary control methods liuvo h(*i*n dev(doped and are now in use. Wit Ik the exception of pickers who are exposed to concciitrutions of 0.7 million particles per cubic, foot under controlled conditions, exposure in all other occupations can he kept below 0 million particles per cubic foot. It is "M with improved methods of ventilation to reduce even the pickj i exposing to less than the ligure indicated. The following recommendations are made: 1. Dust should he controlled at the point of origin by means of local exhaust hoods so designed uml operated that no dust is permitted to reach the breathing zone of workers or to contaminate the general air. Dust-removal devices, which me capable of reducing the dust concentration to a level of ft million particles per cubic foot or lower, have been developed for all operations in the asbestos textile industry (7). 44 2. Since unit 'liul leaving picking machines is productive of con siderable Just, storage looms receiving such materia) should be ex hausted. WoiI ci's who must culcr such looms while material is being Movvn should Ic equipped with approved types of respirators. No materia) shouh he removed from storage rooms white tlu; picking machine is in c icrutiou. U. Clean air dumld replace the dust-laden air reiimved hy exhaust systems attach *d to the ecpiipment. This requires, in event of reeireolation of air, that dust concentrations entering any room he kept ut levels coinpuniole to that found in outdoor air. 4. Periodic studies of the condition of the working environment appear necessary to determine whether the control methods adopted ure constantly adequate. This requires that dust concentrations he determined for each operation. Ventilation measurements are equally important The woik of inspection and review should he performed hy persons trained for such studies. STATISTICAL l>ES< IUPTJON OF EMPLOYEES OCCUPATIONAL IllSIOWItS At the start of the medical examination the physicians questioned cuch worker to obtain a complete record of all the jobs at which he had worked. This information was recorded on the portion of the physical examination form reproduced in figure 2?. After the basic census data (name, age, sex, color, ami marital status) had been recorded the worker was asked how old lie was when lie first began CASE RECORD . Date f frirtk - A*................. * flaw .............. As te(aa aut . Cato*.............-.........................Racial Rteck...............................- ....................................... INriM ................ -...... ............ Yaan wmtkmi..........-...................................Tta Mto-. ..a s. . t>. r. 1 u Srfc PS zx Ip 32 $ a i a *--+* awn i FIGURE 27 --FORM Usro FOR RECORDING OCCUPATIONAL HISTORY. industrial work. Thi- I /' was subtracted from his present age, and a line of qucstiouihg was begun to elicit information on the work done in the intervening years. No occupational history was regarded us complete until all of this time could he accounted for hy delinitu entries. 'Hie job he held at the timo of the study was entered on the top Jinn of the occupational history, together with the number of years he had held it, the mime of the. department in wltieli lie worked, and any other pertinent data that could he obtained. Next, he was asked wluit he had done previously, and again u complete entry was made. The name of (he factory was entered for cuch period of cm- Hfi) 1 d * .i \ 'i i -Mi ployni4*iii in Mm asbestos textile industry. After curb job limI been uccomiled for, tin; worker uns asked what lie IiikI done before (lull. if u man loof worked in mi induslry in wliieli workers lire known to be exposed to pneiinioeoniosis-pjodiiein^ dust, entries were inmlo in (lie Inst eobiinn to show wlmt millennia be bundled mid whether or not dnst-eonirol measures were in use. Inronnnlion on previous employment in dusty (mdes is of paramount importance in n study sin'll as Ibis. Any eases id prolonged exposure to pncunmcoiiiosispioduring dust other than asbestos must be treated separately. After tin; held study bad been enmpleted, an engineer assigned dust exposure values to curb worker, following a pioeednre illustrated in luhle IK. In assigning these values, eonsideration was given to eueli job a worker bud held in an asbestos plant. The importance of the oeeupational history in a study of this kind ean seareely be overemphasized. It is (be connecting link between the engineering and medical studies. The correlations between medical (hidings mid dust exposure that adequate oeeupational his tories make possible provide means for estimating the. dust concentra tions to which winkers may be exposed safely. Only 23 persons reported previous employment in an industry in which workers are known to be exposed to pneiiiuoeoniosis-produeing dust Snell periods of employment usually wen- so !.urt that no deleterious efforts would be expected. Twenty-one persons bad normal lung-held markings. Only one of these 2d persons bad ushestosis at (lie time of this study, a man who Imd worked d years in a foundry m d 10 years in asbestos textile plants. ( v)MI'AitlSON WITH OTHER INDUSTRIAL WOttKKUSI Five-sixths f the employees were native-born Americans of AngloSaxon stock nr d the remainder were Negro mules. Ilefore begii ning work hi asbestos textile factories, more thun 200 of the 541 pcr ns bad worked nt similar occupations in cotton or wool textile plants. A large proportion of the employees bad worked on farms cilia r before beginning industrial work or in intervals be tween periods d industrial employment. About 15 in mtlis before this study was begun, approximately 150 workers in Ouse asbestos textile factories were replaced by woikcrs with little or t:o previous asbestos exposure. Although an elfort was made to cxumine as many ns possible of these former workers, less than half could be examined. Purtly us a result of these personnel changes, the group of employees examined in this study had an un usually low average age. There was an abnormally large percentage of workers with less than 5 years* employment in the asbestos textile industry and an abnormally small percentage of persons who bad worked 10 years or more in this industry. 47 Tami 21 --Age tlittnbutiun of aalnstoa worker* Numtar ot workers Toui....... ................... 2UikUt 20 ywns ............ to 24 years ...................... 25 to 20 years...................... 30 to 34 jeais........................ 35 to 30 yeuis ...................... 40lo 44 yeurs .................... 45 to 40 ytrtts.................. 50 tu 54 years........................ MIo.Mtyrur*...................... (HI to 04 years................ .. 65 to 00 years........................ 70 years am) over................ link now u uye..................... A \ oniye.................... Standard duviation The low averugo oge of this group of usbestos textile workers must be kept in miml in making comparisons of health conditions in these factories with health comlitions in American industry in general Table 22.--Average age oj white male industrial workers Industry Average ag Puldic liaaltli Service Uullc|lu Industry Avtrta I'mIiIIc Health Sori( Ilullotln Iron and Meel...................... tlruinie cuiiIiik...................... fur nHtiny............................ roltery....................................... I*ns| nnlc*................................. foundry.................................... 42 0 30 3 30 2 30 1 37 0 37 8 202 234 Hulilasr................................... Chemical............................... 162 (lanneot................................ 162 35 3 34 8 34 2 33 33 1 33 1 32 a MU 102 HI2 The averugo nge of white nude industrial workers is less in the asbestos toxtilo factories studied (bail it is in 14 other industries in which (lie Public Health Service bus made similar studies. White males employed in asbestos textile factories uveruge 32.1 years, white females 30.4 years, ami Negro males 32.4 years of age. Table 23.--Length o. - . ,.-unt in the uabratoe textile industry / 48 (Wrcspondingly, 1 lie average length of employment in tiio asbestos textile industry is relatively short. Only IS.8 petrent of the employers huve been employed in the asbestos textile industry more thun 10 years. In the lit industries included in (aide 22 for which inforinalioii on length of employment is readily available, (udy two industries have as large a percentage of employees who have worked less than lOyears. This is partly accounted for by the fact that the asbestos textile indtislty is of comparatively recent oiigin in this country. Only one of the plants studied hud been in operation before 11)20. MKDU'AL STUDY HtornaiKE A medical examination was made of each worker employed in the asbestos textile factories of North Carolina during the winter of 10115 80. A group of burner asbestos workers was ulso examined in order to obtain a complete sample of asbestos-exposed workers. Ollice workers and other employees not exposed to asbestos dust were included in these examinations. They arc classified us controls. Included in this control group, which numbered 70 persons, were 27 persons seeking employment in the asbestos industry for the first time. Before muking any medical examinations the iwo physicians made an inspection tour of each factory in which this study was made in order to faiuiliari/.e themselves with the various jobs or occupations involved in the manufacturing process. This is u necessary prorc<|iiisitc for taking a usable occupational history. Space for examination and lliiornacopic rooms ami laboratory watt ohtuined at a location us convenient as possible for ull cnncci licit. A a impiovit>ed din kroom win* iihciI for Ihmroscopy amt for processing tlie X-ray films. fa an adjoining room, tho medical examinations were mudo hy two physicians approximately according to the following hcIuuIoIc; Four persons at D u. in.; four at 10 ill) u. in.; (our at 1 p. in.; four at 2 p. m.; uml four at 3 p. in. In other words, about 30 minutes were re quired per examination. The routine used in the utudy of pnlmonury tuberculosis was followed in the examination of the cheat. After tho history uml physical lindiiigi* had been recorded, the group of four wuo llimroseoped and chest roentgeno gram* ueru taken. A few examination* were mtido in the evening, and oilier adjustments were made in tho schedule no a* not to interfere too seriously witli tho work i online of the employees. At plant A, the urine of workers was examined with particular attention to amount of silica excretion. In addition to lids metabolic study, routine examina tions were made of the sputum of workers in plants 11 uml C for presence of acidfast bucitli and umIm-bIom's bodies. Sections of the physical examination bum used in this study Imvo been reproduced in several plnees in this bulletin us u means of indicat ing the information that was eulleeted. 40 PAST MfcUU AL HISTORY Kuch pit -ui was questioned in order to find out whether he hud previously had eertuin diseases whieh are of importance in the study of chest diseases. FAMILY AMO PAST MtDICAL HIBTOMV 0mjm 0*t AMOtvtl TMtilf MSnt at T .................................................................................-.........-..................................................................... Bifatim to T. I.....................-.....................................................................................................-.........-.................................... Murnlnh............... Tt--I--M.............................. riMrtif.................Dry................... Wat................. HA............... Hf finr 4... ......................................................................... la U.............................. Hn mIA la ikA fwn M< .............. Axf touMSai W wlA r--........... Dwaiiaa............. -.............Baaarilf............ CfcaM....................... TaaAtHCfc .............................................................. ......................rmtoM lajarWa ................ ..................... OywiUwi ..Waart Diawtaa - tMaauU* Unf . 0 l. ............................................................................................. aa*aaa......................................._..................._............ ......... Q (f............................................................................................Nr*aw RdM. ---------------- -------------------------------------------HtoAml..........................................-.............................runaiitto ...........-.....................................................-- OOm xriaaa IflaMan aa wayhSU ....................................-......... --......................................................................................-- miINT HEALTH CM(b.......................In tea*........................-....................... Tr.............................. VHm .. ......................................... -- r.ili r"~i........................... iawal........................................CkaracWr.................................... OA..................................... Ortfaaa ............................ IWktUa ......................................... Batariir................................... rngwMla .........................-- Aaaatll*................................BlfMtlaa ....................................Batoala........................................ Mmm........................ --........... 8tr*ftfc a*4 tMtfy......................................................................................... BraU..-------........----.......... Wlhl: Htaiiaaary................. Lm.................Caiaatf ------------------- Itf W...................................................... OtW aaapUiala ......................................................................................................................................................... --........ -- -- ( irayUai HABITS AkaM .....................................-...............................-............Blaalat ..................................................................-.................. tiHana .....................................................................................CatiBg ........................................................................................ Figure 28 --Form used for recording past and present MeoicALHisroRY. Tabulations of previous illness did not indictife that pucuiuoniu, plemisy, respiratory diseases other than the common cold, digestive 1/1 uu..C n i=2 ZI a. T R ^'Oi| 03BM 1 1 3 r>o disturbances, or prolong! contact with mi active case of tuberculosis had made p ople more susceptible to nsbestosis. Frequent, disabling ruMs won* i ioir common unions prisons with ndvnnccd pulmonary tihmsis tlim they were in persons with lit fie or no fibrosis, but (bis probably is result of (be fibrosis rather (bun u predisposing influence. NVMI'TOMS OP A8IIPSTOSI9 The cbirf symptoms usually associated with nsbestosis nre progres sive dyspnon, c'ii|rli, hemoptysis, emaciation, weakness, poor ebrst expnnsion, curved finger nails or clubbed finger lips, ebest pain, and cyanosis. In these respec(s nsbestosis resembles Rilicosis. Knrly cases, of course, would have relatively few of these symptoms and tin advanced case would have almost every symptom listed. Tbe nppearnnre of these symptoms can be explained on tho basis of ft more or less general fibrosis of the lungs and eoneomitmit pathological changes such as emphysema, bronchiectasis, and fibrous pleurisy. The cardinal symptoms of nsbestosis are cough and dyspnoea. These two symptoms occurred together and in eomhinatiou w itit other symptoins far more frequently tlinn one would expect on the basis of chance nlone. Tahi.e 21.-- Number of persona who had certain pairs of disorders, compared with the number who would be eipeeled to have them on the 6ams </ chance atone. It'here i the differences are statistically significant the observed numbers appear in bold-fact type As table 21 shows, t)4 of the 122 people who complained of dyspnoea had u cough also. On the basis of chance nlone, assuming there was no causal connection between the two symptoms, one would expect that .*{( people would have both conditions.3 Actually, the two con ditions are found together far more frequently than that, and it is safe to assuino that there is some sort of causal relationship. Similar considerations hold for most of the other pairs of impairments. Typically, the cough of nsbestosis is dry and nonproductive. In T his vrIim* Ii tarn mldiUlKl on Urn *s'inii|.tlin U*nl U.2&14 rei'iornli Uir |>rol>nl>llll > H.tif nny mi* >.{ lint iii.1 liaift'lmiiHi'NMmln.rmi t'KrNrtilMltc IIihI h |*rsnn wmiM )m\r Tlifso values are taken Imiiii Uie newmil column of llyiirfs of inWe 1 lien. 0MJ4X0 3vM X HkV- :.S 15 h >i some cases tlicrc is scanty, \iscitl expectoration. Severe paroxysms of roughing orm<=.ionnlly occur in cases of nsbestosis having serious disnhilih Jl ik Ii times highly tenacious sputum is niiscil, Usually a complaint of dyspnoea was entered on the records tody when breathing was labored after an exercise test (see p. <>/>) carried on in the presence of Ihe examining physicians. Tho high pcieentuge of persons with dyspnoea who were able to he at work is undoubtedly due to the sedentary nature of much of the work in asbestos textile factories. Hlood-stmikcd sputum occurred frequently among persons exposed to asbestos dust although there were only two active rases of pul monary luheieulosis in (he group. Theso two en have not been included in tables 25 and 2( and figures 211 and MS. The absence of pulmonary tuberculosis makes hemoptysis n more signifieant finding. Its presence seems to indicate that hrouehiectatie anil emphysematous processes are going on in the lungs. The presence of nsbestosis bodies in Hie sputum (which will be discussed in a Inter section) also cun he interpreted ns a sign of disintegrative processes in pulmonary (issue. Weakness mid loss of weight are closely related symptoins. inde pendently of age mid other factors, these symptoms increase in fre quency with increasing dust exposure. They mo accompanied by a general bodily appearance not unlike that of fibroid phthisic. Nineteen of Hie 417 nshrstos-rxpnscd people complained of a pain in their chests which is best described by the term "substernal dis tress." It was vaguely defined ami not as ft rule very well localized, mid it seemed to be an ache or u feeling of oppression rather Hum a sharp pain. It did not seem to he of cardiac origin. Only one of Hie 24 persons with a past history of pleurisy complained of a chest pain of this kind. It. appears (hat siihstcimil distress may bo connected with the cough or the dyspnoea that accompany nsbestosis (table 21). The symptoms of nsbestosis are listed in table 25, where (heir incidence is classified ncemding to the total dust exposure of (lie persons alTcctcd. For purposes of comparison, Ihe employees of asbestos textile factories lm\r been divided into five groups, which differed in dust exposure, one of them being a control group of employres who were not exposed to asbestos dust. A number representing the total dust exposmv \ a assigned to each dust-exposed employee by multiplying the '* I .years he had wnikrd in the asbestos industry by the average dust concentration to which he presumably had been exposed. Ilis total dust exposure is thus expressed in million particle veins. If a worker had changed from one occupation to another, a dust exposure \nluc in million particle years was calcu lated for each occupation, and these values were added together to obtain his total dust rxpnsutr.* * \n Ciiimplo (litl-lo IK) hits Ix-cn ft It cn In Iliti vi linn niUllctt " I n > <-r I-rrI a) Ion of hul rnimO '* Tlir percentage of workers who complain of cough, dyspnoea, hlood-stmiked sputum, and other symptoms increases in|>i<Ily with increasing nshcslos-dust exposure. In nil eases tlx* percentage of workers who ant iideclcd by a particular symptom is larger than the percentage in the control group. Two of the cases of dyspnoeu found COUCH t*X _____X_____ DYSPNOEA < ,---- X i X X BLOOD-STREAKED SPUTULI X , .'.Yt.. t--------1----------- :-- WEAKNESS Y. *y- X X 1 X 1 CHEST PAIN >/. *y' --------- NO OUST LESS THAN 25-45 CXFOlUftC 25 / SO - 55 *x 1. ________ rivCN >00 OUST EXPOSURE MILLION- PARTICLE YEARS FlGUHE 79 - PERCENTAGE OF PEHSONS. CLASSIFIED BV OUST EXPOSURE. WHO HAD CERTAIN DISORDERS in the c mtrol group were accompanied hy heart defects severe enough to huve caused shortness of hreath. Taui.e 2 >. Clnaatfication of preaent complamla according to the dint ejpoaure of the affected pnaons l're viil lomi-lulnl TuIhI................... *>>.......................... Winkuilnwgt-lilM ...-........ III'nhI ^itetiketi s|>ulilin . rim-l imiii ................. ui u|i|a.-lll . .. 1 I>hi mil ivnlliiLle lui all workers. Another indication that these symptoms are an integral part of the symptom complex of ushestosis is to he found in the relation 53 these symplmns to the fihrotic ctiangcs that occur in the lungs. The degree of !*y* i - can he estimated from the hing-field markings seen on X-ray .uii.inatioii, a suhjcct which will he more fully discussed in a later section. I'W the present it will lie sufficient to say that us a result of long-continued exposure to asbestos dust the normal or first-degree exaggeration of linear pulmonic markings become coarser and more widespread (second-degree litieur exaggeration). Upon longer or more intensive exposure a line, interstitial fibrosis sets in which gives u hazy, ground-glass uppeurance to the lung field (liist- WEAKNESS -/. CHEST PAIN ^ V LINEAR 2` UNEARk|^GROUND'12* GROUND CLASS CLASS LUNG FIE.LD MARKING Figure 30.--Percentage of Persons. Classified by Lung-Field Markings. Who had Certain Disorders degree ground gluss) uixl eventually almost completely obscures the linear markings (second-degree ground glass). Ashcstos-exposed people have been classified into four groups, ac cording to their luiig-f>< Id markings, and the percentage of persons having certain symph> v !a.^ been calculated for each group. Here again, the incidence of these symptoms increases greatly with incieasing lihrotic change. Such a relation is entirely to he expected for dyspnoea, since the discaso diminishes the volume of the lung availahle for the respiratory function. The high incidence of the other symp toms ill tiro preseneo of /ihrotie changes that have progressed to the giouud-gluss stago is additional evidence ol degenerative changes in the lungs. ''* el* '.it ii 54 Tari.e 2U.-- ('tassificntwn of present complaints occurthug to lung-ficht markings of the affected persons |iueum> 0 '.producing dust.. Dining inedieitl studies of anthra cite imitt t tor instance, nil of ||e stupes represented in lignre d2 were found. Among aslieslns-exposed workers, on the ronlraiy, no ease wus found wliieli hud progressed heyond the ground-glass stupe. This constitutes n dilfereiice between ushestosis mid silicosis (lint Mercwether (25), lanzu (IS), mid Pmieoust (20), among olhcis, hnve commented on. Further investigation will he needed to decide whether this difference is due to a peculiarity of asbestos dust or LDNn Km.n mahkinus TIio cliissificiition of loii('-fip|il Mnirkinys used in (lie preceiliiiR sec tion is pin t of ft selicino (lint wns used in ft study of uutlirucosilirosis Cl UOROTCOPtC EXAMINATIONS l#r fniM>wt ........................ Heart. AarU Tr--h-- ............ DUfVni*.............1 .......... Long IkUs ... r.iwalart by' M Ha...-........-.................. K-RAV INTERPRETATION QuaUly f fll--..............................................fcif fr*w*------------------------ Heart. Aerla Tract--........................... -..................... - --.............-........ Dlapkn-- _--------------.......--------- ---------...............------...... L*l flsMe .................................................................--..........................-............ Ciaal--4 br ^ioure 31 Form Used for recouping X-Ray Findings. (_, ni). It is, of course, Itiphlv desirable to have a system of classi fication which \\ill hcln in dccidinp whether u piven typo of lumr>fioi<l nimkinp represents mi early or n Into stupe of a pneninoroniosis, mid (|,is sell me luis been drawn up to illustrate tlie piohnhie seipience of lunp-liei I nun kings that occurs during Jonp-cniilimied exposure to r Figure 32 Scheme Used in Classifying X-Ray markings whether it is due to the rare oceiirrenee in asbestos textile mills of the. excessively high dust exposures (100 to dOO million particles per cubic foot and more) found in eertniu other dusty trades. In a typical ease of ashc tnsis the lower Imlf of (he chest X-rav film lias a line, pranular iii'-umeo which Mcrewether (25) aptly de scribes ns "ground phi (>iot infrcipicntIv, there is more filuosjs on the right side, than on the left. The presence of emphysema in (he apices, which results in ineicascd ludiolucciice, tends to exaggerate the cloudiness of the liases of the limps. Kinphysenui precedes (he ground-glass appearance of the liases, ('best X-rays of individuals with pneumoconioses induced hy other silicates, with the exception of mica,6 do not regularly show the hasal localization of lihrosis that is so characteristic of ushestosis. * I'iiIxiMMiihI i|nhi PLAINTIFF'S EXHIBIT mmmmmrnam ,t .,1 i 1 ) A i i:2 'j >, 1' \ 1 >i /> 1 .1 ,`.l 4 1 ; \ 1 57 Oe asimmlly, in mi esbchlotic chest, (lie heart Ims a shaggy nnilim when \ lowed iucntgcuogf nphically, a phenomenon discussed by uthri investigators. This seems to he of mote fro<(ueut <<ir(<*tt<<* when (ho woikcr inis been exposed to dust continuing n high proportion n| iib<*rs {{{to dust produced in twisting nr broadcloth weaving, for in stance) than when he lots been exposed In short asbestos piuticlcs, particular film n j j. . 11 i > an early or nn advanced stage of pulmoiiury fibrosis. There, is, of course, nn increase in the prevalence of lung fibrosis with aivaneing age. Hennise ground-glass appearance of the lung fields, illicit is indicative of fine, interstitial pulmonary fibrosis, is a most important diagnostic sign of usbestosis, it is necessary to evaluate Lho j NO OUST EXPOSURE1 relation of this condition to ago and other relevant factors. From un published data collected by the Public Ilcullh Service, tabulations of iiiiuii--------------------------------_______ i iiiiiir--------------------------- --------------- --, M_____ _____ j nr*----------------- mm 0 20 20 40 ao` 10 TO o~ PIHCCnT lung-field markings in relation to ago were made on two groups of mini, (tue group comprised 221) men wbo bad never been employed in a dusty trade; the other group included 80 men engaged in mining and M iming kaolin by wet methods. The percentage of men who have a scconditegree exaggeration of the linear pulmonic markings increases with advancing ago. It is significant, however, that in the entire group line: 1 KAOLIN ....... | * JliiUUIUUWUUil_________ ______ i MUIMI ------------ 1 luniinii--------- _j m of 301) men (here were no cases of ground-glass lung-held markings. Other studies confirm this. Precsscn (43a) examined 80 men exposed Id nun bio dust; 18 percent had second-degree linear markings, hut none find ground-glass or nodular markings. Similar data arc available (12) for 201 men employed in portland cement mills wbo were exmaim'd hy (iurdner and Sampson. No cuscs of granular markings or 0 10 20 20 40PtBCSOtN'Tto 10 * 0 00 too uf discrete, nodular fibrosis were found. Jn every age group the proportion of usbestos-exposed men who bad ASBESTOS advanced stages of pulmonary fibrosis is greater than in tbc men not exposed to asbestos dust. Tho percentage of men with grotmd-gluss ' Kffi2S2SHHH[IBHIIIIir Kassaimuiujujiut: taimiiiiir ID luug-ficbl markings increases with advancing age. In view of tbc data (or the two occupational groups just discussed and of Ibe relation between tliis condition and length of employment, it appears that the reason why the incidence of Ibis type of pulmonic markings is cone- in led with age is that the older people have been exposed to asbestos iiaiVitt ri|l M(| Flootit. 33 - PCMCENTAGt" OF MAl.ES Ct ASSIFIC t> BY AGE. WHO MAO CtRIAlN Iung Fitio Man kings 229 Men Mao no pocvious Inousvhial Dust x. aoeusunc mao Ueen Exposed to Kaolin Dust, ano 357 Had Oeen Exposto to Asuksios Dust Tauj.K 27. I{t (niton oj Inngfuld markings to age. Men seeking employment tn a daily truth jar the first time, kuohn wurkeia, and men employed in asbestos textile fadorns sut It h those produced in carding. Further study would ho ncce>Mrv in order to establish (his point . 1 'idike silicosis, nodular ami conglomerate shadows are not found in ushoslnlie woikns in the nliseiieo of (iiherenlosia or other infection?. The priiteipid dtlferenee diserrnihle on nit X-ray film between an eatfy and > mlvaneed stage of ashestosis lies in the density of the ground- glass mat kings and the degree to wliit li the. linear pulmonic no* ^ have heeli ohliterated. Although (ust-degreo and second-. e pioiuul glass markings June been tabulated Heparalcly in several ' - I . |l r M .U ,1) $ \\ 'I A 4 1 s>8 59 dust fur (hi; longest lime. It u<ml<l he important to know wt>'ifcr susceptibility lo nshestosis vaiies with age, hut the*c data tto not seem (o he cvtcn.six c enough! lest (Ids point suli'diiehnily. Tin* prevalence of ground-glass lung-held nmrltiiigs increases greatly - with imrea-dug length of em ployment, as figure 31 shows. The incidence iff ground-ghi^s lung-field markings also in. creases with increasing dtiil CApl )M|I <*. In figure 30, which is based oh table 2m, tliti heights of (lie vertical hers represent (lie per centages of asbestos uorkcfs ill . .. OVf A t) UN' fM Of (HflOr^NI, VIUS different exposure groups who had ground-glass I ting-field Fiouiit 34.- Relation ok GHOunn Glass markings of either /iis( orsecond degree.UiNG-Fici'o MahkingS to Length of The 7 b controls ha\e tMPLOYMt IT . been excluded fcmii (his fahtilnlioi) hihI ii number of workers w hose <|ust exposure whs not Known have also heel) omitted. Many of (he p<*uli; tallies must he viewed ui h caution because (hey are based on sinidt iiuiiiIhts of workers. This is particuhuly true iu (ho groups with more (him 10 years' iiipluymcnl. ('on.side. ing the four dust expo.uro groups ouo at u (mie, (hero is it consistent and tegular inereaso iu (ho perecutgn of poisons with ad vanced stages of lung KClNt*Cl Of .oai *frjciio Jihmsis will) iiirrea.siu^ length of employment. Ago, of eour.so, also in- tienses with length of employment, hut these fihiotic changes (umuit b, o ascr-ibeidiito ad1vanc * >0 III o*t ?o OU* CQmC-| N..T.R..a..Ii--ON. MULION NAtlCLlI Cv (I Figure 35 -Relation or Ghoc/no gi*ss lung Field Maiikings 10 (Just Exposure ing ago because, us table 27 shows, tihuttic ( Indices of (his degree me wot (< he. expected in wmkiwett of comparable age wlm are not exposed (o siliceous dust. Obviously, there are great dilleteuees between individuals in the lime (hut ellipses fiom their first exposure to asbestos dust ami (he time that (ihiotie changes ma evhhnl on X-niy examination. In some persons this was much less than 5 years m{ in others it appears la he more than 10. iff -ugh it is impossible to iiceonnt for these ilill'errnees entirely, it 1. |h> i|i|c that one factor may he the difference in pliysieal exertion that different occupations require. Jn u sedentary m-eupatio)), shallow breathing might he adequate lo meet a person's rrspirntoiy needs; such a person would inhale less ail, and conse quently fewer asbestos pin tides, than a person engaged in vigorous muscular work who was obliged to breathe deeply. Some of the individual differences to tie found in these data may he due to differ- races in the total amount of asbestos dust minded. Figure 36 -Incidence of Ground Glass Lung-Felo Markings in Relation 70 LENGTH OF EMPLOYMENT AND OUST CONCENT NATION Tabi.k 2K.~ -l`,u/,mU,m ,,/ntbnlM Inlilr uu,U,t with groiin.l i/lua3 lung ful,! murlmys |>u-.l r\|<miiru militiui |iHrUiio |"f mi>l In hsIn 'lo.1* In.lii'lry 11 in 1 u i i< vo I \ III O* <1 . . {r|..'*'i ... 11''(<| liliiKV . I \ ll jr ! <i .. - ! All..ml . .. K *!>* 'I - Iuti.ml .. - I'rm.ilm1. It will tie noted that the relation between dust exposure and the. incidence of ground-glass lungdicld mnrhings is not a simple one. liven if length of employment is disregarded, as in figure -If), llm uidetwo of giouud-glttss ituirhings is proportionately lower at 10 to 10.0 million purl ides per cubic foot Llniti it is at the next higher or Fv i <i() "vvi mwn niisi ......... .................. ..nun. Jtmiough il is probable (lint (lies dillcreiiees represent sampling errors dim to small numbers of csfwtsv persons, il may he dial asbestos fibers excite a diMVrenl, ami po*M|>l mou* sovcvo, voav.tinu than asbestos particles. If (his worn line, lit <o(nl particle count tubulated above would not bo a completel satisfactory measure of Ibo pneumoconiosis-producing power n asbestos dusl. It is not mnrusonnble to suppose (but tin* amount of pnhmmuv' fibrosis misfit bo more closely related to (lo weight of inhaled shc-.ln dost than to any other physical property of the dust. The nmuhe: of dust particle* ran be used us n rough estimate of the weight of mosi dusts (InbornImv studies have shown that the two ipnintities an highly conelated). This may not be us good n measure in the ea-w lil |>l A I'll M A ,JM Dining lliunos* >pn examination of (lie chest the degree of movciciit of the dia| 1 was observed and refolded. The percentage f pcuplo with impaired diapliraginalie iiioveiiient. increased with icmising length of dust exposure, and the proportion of workers with rvero degrees of impairment likewise increased. I >rcf<>e "I flAtlo,l Nornmt it,--: Orgrtr of Biiillnii Million pin il, l* >r;ic 1 'niHllilt U,fhr'2r' iMi.Itt MUiOM ft112 Ml 71 12 1 (1 1 0 OK CASKS !'orMr,(Is Million imrUrlr ymn __ Un<Iff 2S 25 lo 111 ,V> to (Ml j/.~relation of Diaphragmatic Fixation ro Dust Exposure the PERCENTAGE OF PERSONS IN EACH EXPOSURE GnOUr* WHO MAO FIRST StCONO oh Thiho Degree Diaphragmatic Fixation Has Been represented by the Height of vertical Bars of asbestos because, us table C> shows, there uvo many long libers in the dust suspended in workroom air. The dillieulties encountered in measuring fillers have already been diseiissed (p. 2d) mid only one nddilionel point need tic men tinned here, A liber ftO microns in length is capable of reaching the lungs (table 37); il would la; counted iis one particle in iiiukitig dusl founts, and yet it would have approxi mately M) times the weight of a fragment of the same liber only I micron i i length. The 2 particles would hnvo the same inlluenre on the d. st count* but one would curry 30 times as much asbcslo* to the lung is (lie other if both were inhaled and retained. Unfortu nately, n "iisiirementH of the weight of dust in the air weie not made. If (hey I id been, it is possible that flic relation between asbestosis mid dust -xposine might have been altered. 7* hr HA 55 Nontml................................................................... If";:::::::::.' 4M ............................. . IK2 72 o ftn 10 3 00 ' Thr vnlnct In the hull ii! llih liilili' wrrn oMfiinifl hy 'IMiUfi* lire VlurS InMIi'I "Intnl l sU-<V ty thr v*IV'a In ll h*w-r Imll(|ho uhl* This is shown in figure 37 where asbestos workers have been divided into live groups (one of (hem n control group), according to Hie total amounts of asbestos dust to which they Imvo been exposed during their working life. Only two of the 7fi controls lind any impairment of diaphragmatic movement. Tor each group (he percentage with normal diaphragmatic, movement, mid slight (-f ), moderate ( I f ), or severe ( I [ T ) diaphragmatic fixation has been calculated. These percentages have been represented by (he heights of vertical bars. Severe form* of diaphnm oitif fixation accompanied advanced stages of lung filuosis. Am .* , persons with first-degree linear lung-field markings, 0.3 percent had impaired diaplnagmufic move ment. Of the 22 persons with second-degree, ground glass Jimg-ficld markings, fiH percent had impaired diaphragmatic excursion. 'I'liis is a reasonable finding, since lung filuosis mid diapliraginalie limitation appear to he part of the same process. I/I -- JL ^ JlC fs 11 52 a. <n ,/ ;.1 i u i "t I 3 i ti`J b;i Diaphragmatic ahum nullities, such ns peaking, <litl not urnir to any sigiiiiicaut extent in asbestos workers although they iiu* common among persons with silicosis. In n study of granite woikcis mined on I))* Ili* l*ul)lic. Health Service (4N, p.N7): "Irregularities of the diaphragm weie in I Iut constant. Korty percent of eases Inul evidence of it, mid tis (lie. condition mlvnnced there was no inciense in changes of (lie diaphiug- mntie slnidows. Them were instances in which angulation of the diaphragm was in evidence, mid others which showed indications of extensive adhesions." In u study of anthracite miners carried on hy the I'uhlic Health Service (SI, p. .r>N): "Decrease in the motihilily of (lie diaphragm ns deinonslinted hy lluoroscopy was frequently oliserved. 'This malfunction, varying from slight to pniftien) fixation, increased with the sc.vcrity of the pulmonary pathology. Not in frequently adhesions between the visceral and diaphiugmulic pleura could he seen." On the contrary, in ashcslosis, with (he exception of one man (lig. -IK), there was no rnciitgciiugeuphic evidence of din* phrugmatie peaking. It ii||4knis that (he limitation of movement, w Inch is a definite part of the symptom complex of ashestosis, may he doe to inelasticity of the lungs ami binding of (he lungs to the paiietes and the inediastimd structures hy lihrons plcmitis. (See pathological section.) CIIVSICAI. HNIMNOS . chest expansion Chest expansion decreases with increasing dust exposure and with increasing pulmonary fibrosis. Asbestos-exposed men were divided into hate groups according to dust exposure, and tho average chest expansion and tho average chest girth nt expiration were calculated for each group. The sumo men were classified into four groups ou tho PHYSICAL EXAMINATION ...... wc........ GmiiI Air*'**4 .... llwlttoAk*! --- *hla * *"* i,H rv>u fMa tin- Umtui.......... .. lrt**uU- . Dmtaip - ImU Tkr*U, NmmI.- ..EMlMlMMft - ..nrMl- - ... _ L........c** ..............rwrMruu . -..........-- ... A>UMy ... nlklM.......... The objective symptoms that ale most frequently ohsei ved and inu-d useftd in establishing a diagnosis of ushestoMs are general appearance of ill health (parlieulaily any signs of loss of weight), the eondilion of the linger nails, and dmiinisbed chest expansion. These symptoms obwoudy appear late, in the course of the disease. The useful chest stalls seem to he limiteil to adventitious sounds. Diminished Ineath sounds, prolonged expiration and crackling rales over the bases of' the lungs and inteiscapular regions seem to at company asbe^losis. Yimous lairs and adventitious sounds were lieatd in (lie elie^is of 5 penciil of tho persons in the contiol group. Hales urte noted in | | percent of (he ashestos-exposed persons who had normal lung' held (milkings or who had only liist-degrcc linear exaggeration. 1 biwever, in (lie group of persons with ground-glass Imig-lidd inniking> (pc trams who had ashestosis), III percent hail lairs or other adxcntltious sounds, in ahout two-tilths of (lie cases, rales peisisted alter cough. t'hanges in (he percussion note are hard to evaluate, piohahly because the condition tending to give a dull note is cmmterhahimcd by gcticiitli/.cd emphysema which produces hype*-resonance. The absence of localized areas of conglomerate libiosis and locali/.cd areas in which tbeie is marked compensatory emphysema obviously ac counts for the Inch of more definite lindiugs. fonFigure 38 - Form used MtcoRDiaa physical Findings. isis of hmg-hehl maikings, and similar calculations were made. The crease in average chest expansion cannot be attributed to any lack f huge-chested men in tho groups with high dust exposure or ad* ancod pulmonary fibrosis. On tho contrary, the average chest girth * " * ,l i*`' i*n'<iiuf dust exposure and with mercustng (A ipfcfec r- ZX >X o --i 2 MJ in a. r-i r M iMAiiinidi . "f'vV a; r. .* f -I ,.g (14 latter phenomenon unit I ti^ available < In I u provide do nicnn^ for diM'iimimiling between them. Since tin* tmol is slight it uui> la* ilisrcgu tiled. The ratio of chest expansion to chest girth dccreiisi's with in<reusing dust exposure. and witli inrt casing pulmonary fibrosis. TaiiI.E 30. lulatuni of uwry chut tffmnswn to i/n.d ispamrc in mule aJnstoM Hunkers < (mr,siim. . k|m s , 1 hi ' Onfuli" H'*iiMn oinMU. to i;irlli Tahi.b 31. Ihtiu *'J III IV -- MllvtW .4 i 44. 77 im - --------------- ------------ . 2 7.1 070 Ot.r i c rnta txpdnsmn Ublmtos uunkeis I'UIIC III III liiitrkiliKS vlmicdin. tin in * O inti l . ..........................,,s Kudo hi Co cirlli. luimr S> i nml ,|. tirsi .I.khi K*' i' hii.'ur gr<>'iii,j 4J 77 IhH 44 .*7 U7b 2 .10 44 Mi ( 'best expansion (ends (o decrease somewhat with advancing but the avcragi* chest expansion is less in usbest os-ex posird men n gi*, it is in men of computable age who have not been so imposed. than Hint, r jn . lit JV J(l In Jll III III 4U Ml In Mi. . tWin Oil Taiii.k 3Z--.in*aye chest expansion of mu/ts .................. ----------------. r'ljKM-i lu lnuliu - _ - ----------------- <H lid*. I'.lllr 1, "<N ' |..|| Mol I'kjlOM'it lo <llis( -------- -------- NiiiiiIkt of UM-n in ugc K<UI||> A v. niKj On >( ot. JiuUimu NmuU f ,,l in-m hi ii|*o K'uiiji ------- ---------- A u n,,*,* 1 ln>l luihilult ................... NimiiI. lo<*ti In HKt K**mt A l r|ii|;ii !. -.< |Hll|iMU N 2 00 an 2 JH 22 2 IN II 2 ill 0 4 17 4 J HU 1 /ill hts < 4 ,,'i 47 IS 4 II 5 2 Ml 4 t M 2 2 III tin Mi i 4 JJ> 2 l*t 2 j j.i i i.\ lvxtiTiuilly, the thorax shows evidence of limited respiratory movement; the siipm- and jji/ra-rhtvicufar fossae ate conspicuous; the aiiterior-poslenor diameter of the chest is increased; the siibslcriud angle may he jnoro obtuse; evidence of wasting or loss of subcutaneous fat may bo present; certain of Iho accessory muscles of respiratiou <ir> imiy appear to I * tmpbied. In other words, the general appearance, of the i m.l that of lihroid phthisis plus emphysema. Among the conditions (but limy reduce chest expansion tiro pleural udhesions and the relative inelasticity of lihrolic lung tissue. HESI'I II ATONY HATE The direct effect of pulmonary fibrosis on respiratory rale may he seen in table M. lh fore the exercise test the respiratory rate of nudes with ground-glass lung-field markings was higher, hut not significantly so, than the respiratory ruto of mules with first degree lineal cx.iggciation of pulmonic markings. The exercise test consisted of having the subject stand witli one foot on a box 14 inches high and to raise Ids oilier foot to the level of the top of the hox 25 times in 20 seconds. The respiratory movements were counted during u J5-seeoml period preceding I tic test, during a 15-second period immediately uftcr exer cise, ami during a 15-seeond period 2 minules after the test. Kxcirise raised the respiratory rate of all four groups of men, hut the rise in respiratory rate was dependent upon the degree of piilmonuiy (ilnosis, the men with ground-glass lung-field inarkings being alfccted most. After 2 minules' rest, the fall in respirutory rate was again dependent on pulmonary fibrosis. The respiratory rale returned most closely to (lie prccxcrciso rate in men with normal pulmonic murkings or with first-degree linear exaggeration of lung-field markings. The return to the preexercise rate was slower in men with ashestosis (groundglass liing-liehl markings). Taui.e 33.--Hclntton of respiratory rule to lung-field murkings in male asbestos workers I.uiig field niuriiiiKk Ateruce rc|>lrulory this Ihit-ur BmiiiiiIilrcrce linear Hoi <inire KrtHimllilWiI S.v.ni.l- ill'KMS Orminii- Ulna* Nnmliff ol men eiHMilitt-.l......................... .. Ih M<- eiun-i-^!................................................................ Allor eii-ii'ibf ............................................................... 4 niuniltt nllvf eaeuiM............................................. 'Alt IN 1M0 17 '."i li`> l 44 "n 4i l 07 Hi Itl 34 tO 42 .U t M 21 :mix 12 SI At 221 0 MU 2H 04 i 1.0(4 21 47 .OH .M 21 Ml t 2 24 40 Ml 1 1 III 24 21 tl OS Taui.i: 3-1.-- Influence of unthraco-sduosis on the respnutonj rule of auf/irucife miners 1 A veratie X|*omkI In lIllSl, |-.s>cll1 lully imiiiuil Antliriu u.l|tii*5ij Niunlier of men eiuiulueil Hole t.< foio nniiiMi... . Ilulu alter etrxiMi................. Kale alter ie>l....................... 2,001 IH 74 LO HI 2U 00 | 07 22 74 L OH mu 20 41 i 0 III 31 lu t. 02 20 101 02 1 Tilt* (IbU were nut ln< lu.lixl lu I'ul.lit Jleafifl fnilirlfn Nu. 4.1 Si11liInr relations were found in a study of anthracite miners. In mm with nnthrnt o-silh osis the respiratory rate was definitely higher than in essentially normal men before exercise, after exercise, and lifter rest ( MJIIUINU OK MNliKKs AND CdltVINO OK NAILS Many ushestos-cxposeil workers, parlieulni ly those with long dust exposures, had a deformity nf the tinker nails. The terminal phalanges may heroine so hulhous Unit the tinker resemhles the end of a drum stick, a condition touwiiirntly described hy the term cluhhed lingers. Usually it is accompanied hy a dow nvvard curving of the end of the nail. The ulTn lion is almost always bilaterally symniehieal ami often involves the Iocs as well as the lingers. It is eomnum in pulmonary tuberculosis. In hiont hiectasis, empyema, and congenital heart disease it may lie seen in its most exaggerated form. Sneh exaggera tion, however, was comparatively rare in this study. In a study of *2,711 (f>l) nullum ilc workers, the deformity, regardless of degree, was observed in ahouL a third of the workers having iinlhrnco-silho-.i'., hut was piesenl in only 4 permit of the controls. The teal signifi cance of the affection has not hecn determined. Norris and lamdis (02) stale that in all piohahility it is a inamh -.Inline of long-standing toxemia assoeiated with phthisis or hronclm ctn . The hrom hiecIati<t and emphysematous changes noted in the ashcslotic lung at autopsy piolmhly account to u great extent for the oeemreticc id the. change in the workers with nsheslosis. Taiii.l 3.ri - Nuiiilit i uml /hia nt of <r>t ilns-tifiosi it woikt . jc/m hint clttbln J jutyt / or eiut'iil Jmyvt aajf.i, WiisKijirii Uij luny /uiil unukthy 1 v nl IhIiMiii; ..................... .. K||nI III .ir ... . I.ir (out l.iltiH Hell in.irkinti *... Iiiii'iir Hi-1 litnti nc'ini'l kI.uo w.. Ir IVtIClll Niiiii. In-f tOfont ..... ...... cruillnl to I,( uni T.Kill .. JIJ mo +Ni.rtu...il............ ... II ....................... +H . 7 Mil 37 U B3 11 7m Ul I.J 711 10 It II H a0 ..... |ij 31 i.J 1.' .M S 10 i4 ... 11*1 11 t.l II U 0 I) Five controls (It percent) had curving of (lie nails. This percentage was mud higher (I!) 2) in the nsbrslos-cxpostal group. Thirty-nine priernl < f llie workers with first- or second-degree ground-glass lung-field markings had (his condition. . IILAtVf DkltkliTB Taking ago info ronsidciutinn, Idoial pressure values confomieil closely to tIn* values found on examination of 10,Nil malt; industrial woikeis (fli). , 67 ....... . ....... ................""" sssssrjssjss&'sssai ....*<* ,Z..... 'r:i l slmly (iikIikIiiiK i.Jrt ii.i|iiiin"l'"ls > 1,11, ,.,I r.M'S III nslicstiisin 2*-- -.... " -.......... ..... ''"8t eX|'"SUI" : :;-S i'Kv': riU: \'r \ *; : i.'i ASliChTDS COHNS Asbestos corns are waillike culhrdhcs, 1 min to 5 inni in size, usually located on the palmar surfm < .0 mis or lingers ami occa sionally on soles of feet or on the legs (sec hg. 30u). Their presence on the palmar surfaces of the hands is explained by (he fact that workers, on breaking threads of asbestos, force liny slivers of asbestos mold the skin where, it initiates a foreign body response. This response is characterized by hyperplasia and liypcrkeializalion. Table 3(i shows that the oeciipntions in which usbestos corns aic most 'ouiinon are ones in which workers test the tension of moving UoeiK s with their finders, or in whieii they are obliged to break thicat's with Lhcir hands or to knot threads together. Taiii.k 3t>.-- I*erceniuge oj asbestos workers who had a>brstos corns, datmjitd by occupation ` Occupation T*i',lrh............................................... Cnclors . .. ................... Tu|* mirf liruku luiiitK wwsun, ' . ..' <iin|ki Io( , ti.lon.lws, uml IlnMier* t l.*0i h> vera................................. < 'ni>livr . ., , ............... V*ir 3|h.|hm and whi<lrr .. . ......... Muli uml rlut: .-iplimi'ra .. .......... Ciinlrra ..................................... ' "........ J'loiilfiil, sienii^irtphers. aiul clurka I'n uml pilcfa ................................... WiIIiimi'i.s mu| |inkoriiiii t'"rUrs .. - .. hurtin g iiimI I'tlmlrfs........................ <'r|*iiili-rs. >uf.hiini. umi rn^-Ot waUlmi'eu Milliliters mill Mi|H<iinteuileula 1're eiu|il.i) iueiM. ................. NuniU-r emplujcil JVrtviu "llll * lUxsi not iiu ltulo O tamilly iPsiI>h?r<| workers. Microscopically, Dcwirtz (10) stales that the rows present u picture of slow chronic local irritation. The horny and Malpighian strata of the skin an) increased. Hound-cell infillration is noted particularly in the papillary layer of the dermis. Asbestos libel's or crystals aie also vseen and they aie regarded by Dcwirtz. as the agent responsible for the thickening of the reto nmcosum, basal luyeis, and the giantecl! fonnalion. (iloyno (11>) has also found asbestos liber in the eorns> hut noted that asbestosis bodies of the type observed in ashcHtolic lungs and sputum were Absent, The workers have themselves called these little tumors "asbestos corns/* or asbestos waits. Not in frequently tlm coins become very tender, particularly when pressure is applied to them in the course of handling tools or machinery. On account of (tie pain, the workers will attempt to remove the spieul of mincial with a pen knife or some oTier sheip iiistiuiovn'.. St 'nd the fiber he incompletely removed, it icuus with greater h.Ypciplasia fiff heeause of the added trauma. Most of the workers so afllieted insist thut every hit of fiber must he removed before the coin is cured. Only occasiomdiy, however, is medical relief sought, ami in such eases Dcwirtz (10) advises complete surgical removal LAUORATOHY HNIMNOS ashkbtohis mums Unusual structures have been observed hy scvcrul investigators on histological study of the lung tissue of men who had died from usbestosis hut no detailed description appeared until 1027 when ('ooku (0) and McDontdd (22) published photomicrographs and discussed the conditions under which asbestosis bodies are formed. Their papers apparently awakened interest in the subject and several papers on asbestosis bodies appeared soon ufterward. The following review of the literature on asbestosis bodies is far from complete, hut it will serve to indicuto the kind of information that bus hern put on record thus fur. There is good evidence to show that these bodies originate ns a cellular response to an inhuled asbestos fiber. The core of the body is un asbestos filler which is surrounded by protein do|u>sils. Apparently asbestosis bodies are formed only in the lungs. They have been recovered from the feces (30), suggesting that they puss unchanged through the gastrointestinal tract. They have not been demonstrated in the asbestos corns whi !< form mi the bunds of asbestos workers (10, 57u), nor iu the peritoneum of experimental uiiimals (57) into which the dust bus been injected, (bmlnei (57) found the "bodies" in the lungs of dusted guinea pigs, hut for 9oino unaccountable reason found them to be sparse in similuiiy exposed rabbits. The bodies can usually he demonstrated in the sputum of patients with asbestosis, although, according to Lynch and Smith (38), the sputum may be negative on repeated examinations even in well-established eases. For eases of this type, lung puncture (40) has been suggested as a diagnostic procedure. Asbestosis bodies are variable in form (lig. 30a) and in size (table 37). Characteristically, they are slender, elongated, segmented structures with bulbous ends which give them a dumbbell or drumstick shape. Occasionally, a forked or Y-shupcd body such as the one marked // in liguro 30 is encountered. A rosette such as the > ><<> ilhi tutted in the center of figure 30 was observed only once in the examination of sputum samples from 281 persons, ltuscttes, however, are common in sections of lung tissue. Stewart, Tatersull, und lladdow (41) say, We miKKCut llmt the limlings of a large clump or clumps of usIh-nIom* Imiiicrt in the pputuin its here dcecnhed in a dear imlicntioit nf ilihintcgratinn of lung tiseuc, whether hy a pmecH* of wimple Hiippurativc hroneho-pneuiaonift, uh in our hrnl < or *:. renal' f htoI'i'i'M f ol- r <oIouh (v f-cU<m J li lilt hot CtWQ it is rettrto/j- afi.e to ront-lmfc (hat then n a n-. Jimlc uclerlying at>U:wlnhiN. a 70 YI * MU IN 1 IIE CAMij ROOM ,,F .A' F ^YEAW-OlO tMi i </yel 14 Years in Coi .,>* a A5>ULb,tls Itxni e Tac OF Muuca^e 2X ,ON ANU Woolen lexiat Ml Empioveo 4 PREVIOUSLY PlIOTOGNAPH 71 Tlir asbestosis bodies illiisl rated in ligure 30 show some of the variations in size and shape seen in spnlmn smears. Kive of these asbestosis hoilies (A, (', />, K) were found on (lie snme sliile. This sample of sjmfrnn was obtained from n 37-year-uld mule spinner who hail been employed in the asbestos industry for 7)* years, exposed to an average dust eoneenlration of 8 million particles per cubic foot. Ilcnmsc he made no complaint of uny of the major symptoms of asbestosis and because his lung lields were second-degree linear, no diagnosis of asbestosis was made. The bodies labeled (i and // came from another mule spinner, a 37-year-old man employed 2% years in an average dust concentration of 7.11 million particles per cubic foot. Kxrcpt for a cough he had none of the symptoms of asbestosis uml his lung lields were essentially normal. Jn several photomicrographs of the "usbestosis body," the asbestos liber may be seen dearly. The bodies are somewhat fragile, ami frag ments (such as L in fig. 311) often occur. Unstained specimens are golden yellow or golden brown. They do not stain with the aniline dyes ordinarily used in histology, but they stain blue (prussian-hltio reaction) when treated with potassium ferroeyanide.* Asbestosis bodies can be demonstrated on sectioning lung tissue. Since they aiise as a tissue reaction to an inhaled asbestos liber, their size is important because it indicates the length of the asbestos libers that may reach the lungs. The greatest length of the first lt>8 asbestosis bodies found during the study of prepared sputum speci mens was measured on camera-lucida drawings. ICvcry asbestosis body was measured and the frequency distribution of these measure ments appears below. Taiii.e 37. - frequency distribution of the lengths of the fust ttiH asbestosis bodies found in sfnitiiin smears Ixingili lii iiiicioiia Nniul.t r nf h.Ih-is lui.llt s of ll Itii.fl). s|mHU-iI 1 i'i>Kl It ill mil runs Ninnlx'i of tt ,U ittlsIS ImhIios of On) li-iiKili S|Mlllft<xl Toluf tneu.Mii<l ............................. U lu U .................................................... Ill lt< III ................. - wui at .......................................... Win 311 . . ........................................ 41) In It) ......................................................... ao iu ,w........................................................... U.N fill In flu......................................................... 71) In 7U . .. ..................... 0 8(1 to Hi) .. .. JN u i lo ini . . . 37 IMta liv . . ... 3V 1 Hilo lit).................................. . 2a 120 lo 12V.............................................. h) 2 3 1 2 1 1 * Oluy lie's (.17) mellmd wus iimxI in tin) (tresenl si inly of nsJivMosl.i Ixxln-s In s|>iiIiiiii A smnideof sj'utiiiu is dii-nslv'l witli tin e|iiu| Millline of i omen(ruled nut Hot min, n<nirifni;i >1 >il modrinU' ll>* unlifiiiinin h |ill*diod nil, uli'l ri)|ilm ett * Itli the following in Ik line. 2 |*-r iviit |>ol n.ssnr m frrrn i) iiiddf, 1 |>il, 1 |k Kent hytlimliloric mid. J |iu(h Tlie IiiIhs is Ouikrn uixl allotted to Uniid for Iv l<< I lioiir. It Is lltan ittviilil fiiKft'l uml ilia nmli'iiid moiinlud ns a wot |>i |>n ulIon Witli Uni lt-(hni<|iio tlio ii'.l.cido-ds ImhIics uie tolorod Inilliuiil Oliio If iiioiiniixl wltiiuiK treat moiit witli jx.iuiinim firr<x yunidf mid hydriHldorlc tut.I, ||i IkmIivi mo yoMrii yellow In oolur. 4.U0v* --1 -- fl V.'i ji i rr y* 1 ;*`U a 72 The asbestos bodies ranged in length from 10 to 128 microns; their average length whs 85.1 microns. After completing (his series, routine measurements were discontinued in < this seemed to l*e n large enough sample to indicate the si/* <1 hcslnsis bodies most frf`(|iiently found. The largest hody found in subsequent study of sputum specimens measured 181 inierons in length. There seems to be no eompletely satisfactory explnniilioii for the ubsenee of nsbeslosis bodies measuring less tlmn 10 microns in length. Asbestos nppenrs to dilfer from other pncumoconiosis-producing dusts with respect to the si/o of the hugest piutirle Unit limy rciieli the lungs. The largest reported upper limit of si/e for rnek dust in the gold mines of South Africa and in the granite (48) and anthracite (51) industries in this country is 14 microns. The data of table 87 are in harmony with a concept that has been gaining support in recent years, namely, that particles beyond It) microns in size /each the alveoli. Measuicments indicate that the diameter of air sacs may he from 150 to 800 microns in adults, or, in other words, of such a si/.e that asbestos liber or resulting asbestosis bodies may be readily neeommoda ted. Asbestosis bodies were found more frequently in the sputum of persons who complained of a persistent cough than in the sputum of persons without u cough. This is a reasonable finding, since the net of roughing tends to raise materials from (lie lungs. Half of tlie 5(1 people who complained of dyspnoea bud asbestosis bodies in (lieir sputum. lx*ss than ii fifth of the 225 asbestos-exposed people who did not make a complaint of dyspnoea bad asbestosis bodies in their sputum. Almost the same relationship bolds for a complaint of cough. Asbestosis bodies were found in (be sputum of 4(.0 percent of persons w hose condition was diagnosed as asbestosis. A much smaller proportion, 21.8 permit, of essentially noinial asbestos-exposed persons bail asbestosis bodies in (heir sputum. Thus, it appears that the pre nice of asbestosis bodies is evidence of exposuie. to asbestos dust, b l it is not necessarily a diagnostic sign of asbestosis. Asbes tosis bo lies were found in the sputum of prisons who bad been exposed to nsbc tos dust for ns short a time ns 8 months. Of the workers employ *d less than 1 year, 22.5 percent bad asbestosis bodies in their sputum A larger percentage, 88 percent, of workers employed more than 5 years had these bodies in their sputum. In evaluating these percentages it must be remembered that they are bused on the examiniilimi of a single sputum specimen fiom each individual. If scveiid specimens could have been collected and examined, the percentage of persons with asbestosis bodies would almost certainly be much higher. No asbestosis bodies were found in sputum samples from any of the 70 persons tested who were not exposed to asbestos dust. 'Hie incidence of asbestosis bodies increased with increasing dust exposure. Tahi.e 38 --/frlilton of t/n.tl concentration to occurrence of nthcxloxt* botlifs ". ........... oi|Hi*>r<t Niniil8*r 1 wllll >tir`. 1 ImmIU'M Tot>l *<cp"w* 0 tu 4 U ... StntM# HltiiCMt . . 20 nii'l iivrf - 2H| 7 23 W I.U 74 4 21 17 # 21 9 23 28 31 1 3*> I KEHCI.TH OK TEST* ON tlttlNK Hitch person employed in the three asbestos plants studied was asked it hring a 24-hour sample of urine in a metal container provided for Imt purpose- In addition to the sfandaid clinical tests, the silica onlcnt was determined by the method of King and Dolan (5!)),7 Of he 4I(> persons exposed to asbestos dust at the time of the study, urine umlyscH arc available for 408, and these results have been kept separate rom the results of urine tests made on (>7 persons whose work did not xApolsboumtheinmwtaos afosbuensdtoisn dlbuest.urine of 10 of the 248 white males tested; in the urine of H) of the 08 white females; and in the urine of 8 of the 57 negro males tested. Only one sample of urine (from a white nude) rontniued sugar (Itonedict's test). These rates of incidence are n higher than in the controls and, insofar as published data arc available for comparison, they seem to be no higher than the rates generally found in industrial populations. Taiu.k 3!>.--l/clafinn of urinary *firn to (hint exposure (Minify *!' CmiMiW Unit r (*osurr, million |rtt h-i jh>i njl.li- (mil | IIII.. 4 9 1 ft lo 0 9 ItMn UIW Ov.rVH II.Kfuiiii I"* ,'H,rr lllt!KI'"1 sHlO* I"-* O'ly* niU r ImIM . 3 11811' II 30 4.ri>. . 14 3n 111 52 11 2 HH HI 30. 30 * 78 2 lA to II W 47 *1 30 3 41 I 0 10 37 55 t.l 31 Silica was present in conccnlnitiuns laiigiug from 0 7 to II I mg r 100 ee. Average miimry silica concentration > for <"nups of rsons whose dust exposuie varied widely (table 80) do not imiicato iiit there was any simple relation between the exposure to asbestos ist (wbirdi consists of hydrated magnesium silicate) and the eon 'll(ration of urinary silica. Kather, it appears that the values for > Tlif ml..rtitifl fir Un..tr<rrMiluiU<irrf On In ll>r mli.f consuls In Ihf |>n*lni tonot n'ili. /|yl.JIr nrtij romplrr ulilch Is lo gl\ a l.ino tutor. tf.e .tfjSt* of o/lof lrm* |>r>.|'ii>niiii) to Itis iiiNHli nf iltlro f>rsri>t. iO IJ i 4I 'I u ' ,I I 5 74 du^t-exposed persons fluctuate above and below the value fur the controls. 'I'Im1 tIill diiily silica output was <*>I*ukited by multiplying silica concentration by the volume of uiim * . . led in 24 boms; llicsr values ((able if!)) also show no simple relation to (lust e\posiue. tliimuy silica analysts are available for tun other groups of people whose diet resembled that of asbestos woikcrs in consi-ding largely of vegetables. The mine of seven male college students living in the same, city averaged 2 ti mg per 10(1 ee (based on single specimens, not 21-hour samples). An earlier survey of an industrial plant in Ten nessee made by the I'nhlic- Health Service" showed that the daily silica output averaged 2!I.N!> J.0.20 mg, ii value very dose to the mean silica output of nonexposed asbestos workers. Diet play* an importaiit pail in intlucming minnry silica con centration as King and Dolan (50) have demonstrated on experimental animals. A predominantly vegetable diet, with its high silica content, leads to ii Ink'll miliary silica output. Jt may la* that Hie dirluiy intake of silica was so {'leal as to totally mask any possible Hire! of silicate uhsoiptiou through the hint's lit any ease, the phenomenon icpoiled by King and Dolan for ('old miners (50) and by the Public. 11 in 11 ft Service (51) for anlliracile miners, namely, a higher silica excretion in men exposed to silica dust (ban ill nonexposed controls, does not appear heie. The urinary silica concentration of the asbestos woikers is higher than that reported for the two occupational poops ju->t mentioned, and this appears to be largely tine lodietary ditlVrcnees. Silica concentration increased with increasin'' specific gravity. 'I'hc silica content is, of course, too low to influence the specitic giuvily ducelly. Instead, it appears that the two values may vary concomitantly, and that the diinking of hup* quantities of water, for instance, would lower both the specific parity of the mine sub sequently exeieted and its silica content as well. TAio.t III.--lit liitwn of ailun content of unne l<> sin-njic grumli/ --' ..................................... . S|HfCilk goully ----------------------------------,, Awr.i*:*! MlH.llulMcill - -- Numlx-r til . l mm | miu 1 ">'i t.< I mu ' i ii.it in i itfj . ..(.I.t .o.r .1.U.R.i.......... Mf l>rr IWrc i II 2 r.>j 3 HI & 10 -- -------- 2S M>.< an 2J tiik iimunonis or asucstosih In preceding sections of this hulictin the signs and symptoms of asbestosis have been treated one at a time or two at a lime in order to show their relationship to dust exposure. In lids and the two followin'; sections the symptom complex of asbestosis and its relation to dust exposme will be discussed. * I'ih 'iMi Ih'I IiiIh 75 - (heu(Kitionul hisloty.-- In establishing u diagnosis of asbestosis, it is important to excludo the possibility that the observed effects may have resulted bom inludatioi) of another kind of dust or some other disease process. An eailv case of silicosis, lor instaic might present sipis and symptom* which would differ from those of asbestosis mainly in degree. A diagnosis of asbestosis should be made only when the occupational history shows previous exposure to asbestos dust and no heavy exposure to other siliceous dust. X-nty JtmliinjH.--Although tho ground-glass markings that aro so characteristic of asbestosis are iisunlly localized in the basal portions of the lung fields, nevertheless all regions of the chest must lie examined locntgonogrnpliicully in order to detect signs of other disease processes that might complicate diagnosis. It is important, of course, to look for the signs of pulmonary tuberculosis. The distribution and the character of lung-field markings are significant. Sbaggincss of tho heart shadow (see ]>. 50) has been mentioned by several physicians who have reported cases of asbestosis. The physical findings should be referred to whenever cardiac enlargement is found during the X-ray examination. A consideration of the chest shupo of the individual wilt sometimes modify tho interpretation of certain of these findings, KJuoroseopic examination is, of course, the best means of detecting diaphragmatic impairments, but valmible informa tion ean often be gained from u study of a client X-ray film. Heavy pectoral muscles may cust an X-ruy shadow which resembles in a single plate the shadow cast by the increased fibrosis in tlio buses. Tins possibility must always bo kept in mind during tho examina tion of chest X-ray films. Nolas on the thickness of the chest muscles should he entered on the physirut examination form, or stereo lilms should be made in order to obviate this source of error. The presence of bronchiectasis caused dillicully in diagnosing one case. Clus.iificution of luny-fitll nntrkuHjs.-- In this btudy, after examin ing an X-ray film and before making a diagnosis, the film wus classi fied according to tho natuie and degree of fibrosis into one of four classes; first- or second-degree linear exaggeration of the lung-field markings or first- or second-degree ground-glass hing-fichl markings. There is good reason to believe that these four clas.se ropre<cnt successive stages through which a typical case of ushcst<< is wmld pass under continuous exposme to asbestos dust. Since, its 1ms been said, the ground-glass markings appear first in the basal portions of Ibe lung fields, it follows that any given chest him might have ureas in which the markings were giound glass and other areas in which the iiiutkiiigs were linear. Usually the basis of classification has been Hie typo of marking that predominates in if in lower third of the visible nng field. iT.'. 7 li 77 SECOND DEGREE linear FIRST DEGREE GROUND CLASS In order to .show these markings on a larger scale tliaii would ho possible if the entire film wore lepiodured and to illustrate this system of classification, figure *1(1 hits hern prepared. SyutffUnttH.-- Dyspnoea, cough, blood-tinged sputum, pain in Ilio chest, weakness, decreased chest expansion, curving of (he finger nails and adventitious chest sounds are symptoms which also ocenr in silicosis. It is possible to differentiate pulmonary *!> *' >ds from silicosis hv history of exposure to ushestos, the presence of ushesfosis* bodies in the sputum or lungs, and by the type and distribution of tlio X-ray markings. With reference to ashestosis bodies in the sputum, the data show Unit they may appear after 3 months'exposure. They show evidence of exposure to dust, but not established disease. Lynch and Smith (38) reported difliculty in demonstrating (lie bodies in an ad vanced case. The presence of rosettes as illustrated in figure 30 has been reported to he of greater diagnostic significance. No advanced cases of ashestosis of the bed ridden type were observed in the present study. Reports (13, 20, 20, 32) of fatal American ashestosis cases whieh were relatively uncomplicated by the presence of other disease processes are essentially similar to reports of uneomplicated British cases (!), 14, 34, 35). Butients in the tcmiinui stage are usually reported to he emaciated, markedly dyspnoeic, cyuimtic, and usually liuvc a severe cough with wiry mucoid sputum. IteritfcUENTATIVB CASK IIISTOHIES Hates made from representative X-ray films appear as figures 41 to 51. Uoentgenogrums of a normal chest (figure 11) and of a chest showing advanced silicosis (figure 42) have been included for purposes of comparison. In figures 43 to 51 which represent ashestotic patients, an abstract from the case history and phy&icul examination accom panies the X-ray. In viewing these roentgenograms it should he remembered that the ground-glass lung-field markings that are elnmicteiistic of ashestosis are exceedingly dillieidt to photograph and reproduce, it will ho noted that the distribution of the shadows is not <|uilc as general us in silicosis. 1 CiHiku Inu iu|M>rlt<l M>mliut bimltur hmiius lu (fia from m>l>tuliuia Laxl'e* </ uiiiru< Jl nilortt, l>ur they miu to illller FlOltUL 40 - Poi^TlONS OFCHEST X Rax, ct Sivt Chancl i. BHOU5HI ABOUT Abutbros Uubr. " Lour'''LLUS' HAT1 THE s,,cc5 Long Continued Inhalation of 4T lA* ;*A m .Vi X 4 PLAINTIFF'S st EXHIBIT 1510(45) I FIGURE 41 Faiu.Y ASBESIOSIS. Willi E Mai.C. AGE 29 (h'ciipittiuinil t'arder (u.sle.slos), I'j \riiis, <>( 11i->l y' Irade*. V.- \ra#v I'^lminUtl dnl x/nU'or. - (n) d.VJ million |iutlirler> per (illtie fool. <Million |>:ii I n it: S `n'r4, I-*'! No .signifu uni past inedieal lindiogH or enni|ilniid.s. /'fo/so iif ixiiiHimiiinii Intermediate, slendei while male. Height, *7'i in !>; iwi^lil, i iJ |*MN|s, llnllirr lim^ ehest; e\|iiuisiun, 2 inehe.s N't* i ill fiemihts, Im utli .sounds, or percusMnn note. Illood jnessnvr, ItiK l IS. I'ul'o lull', '.Mi, 120, and Ml liefoie, immediately jifliT, nod 2 ntinnlm nUrt hunt mnal e\eiei-,r I1 II uni > nihrii, 2 mg tier Kill re (2 i limn nut pul, d 1 -I mgl Hoot me iirin.ilyM-s negative; speedo; ginvity I 1122. A -ki u ii .sl-degi re gi nimd gliisH ap|m'ui a nee iml ipnle nldilei nl mg I lie enai -e linear huhhing* Noli- the hoc, ilo.se-sel reticular inniking.s jtial olf eui h liilmn itml tin nphe* tnit.titling <(nil<; clnir. /1oujao> Kmly usIk-sIom* without symptoms enmphrnted l*y hypeitensive he.ll l dl.se IM`. Figure 44 Early asbestosis. Write Male, age 39. th'njaituooif hislnifi Mule spinner (uxlieslot*), tuni I/ yeurs; roving attendant (ii .lirbloH), I year, nondu.'ily trade*, H', i yeurai'ttiimitt,l ifnil rxfittsni c<ul Weighted average, 10. !> million particle* per mine fool (f>| Million puilnle yt-aiH, ifiH 2. 1`ttbt ini tin nl,- Nhrapnrl wound right parietal region of head, Ortoher l!MH. Itiliilnnl pneumonia a* u i lutd. t 'nwffltlinlx. - Slight \v eilU lies*. . nl tnitniimtnm Intermediate Imtfif, fuilfv weft iimuisNed. Height, Oli'i liehes; \\i igld, I I I pounds Client ekpiilision, d*i Riches lllootl prcnsMie, ldti/82. I'oIm! mlr, Kd, 120, ntnf Kf, iintf respuutoiy rate, Jh, 2f, and 1H (renpcelively Im-I i>, immediately after, and 2 minute* after fmirlnmul eserrinc lest). Inter mediate rhest type with .slight mi'irjiM1 m A I* diameter of rhest IVw rmoperMsteut molding rales at light Inise A.she.slu* emu on |ialmni Mirfa> "f lift uiibl Sligld, eyanobib of Ii|i% untl naila. A dtibl>y led ea'.t (> .us i.ntooi negative fm It. tnlh n uliho ami iihlieslos Imdien. Urinuiy hitiea, d (i mg j r KMIee (21I'lltinonotabm, n2/1i//T -toMg)otleiale (2 | ) (iootidioii of tliii jilirngnial le i'\eiirMon. llila niiMlemti ly inereiised in M/e and t|eiist(y. X imi No(e (lie (ii ,( drgtee grainy or grooml glass ii)>|eiiianeet not nlilitnr- idmg (lie linear nmikingH, giving general lelieolur a|>|a`aranet: to long (irMa. (aenerali/ed filnosi.t I | />id^ddis - A-slie.-dobi.s 2. HA i F,uunE 45 Moolimiu V Advanced flbbibiusis WmitMAtc, Ar,C4i, Ou-HfHtlititml h>'U<iit Mm mi It I' *1 It uc;i\<-r (u.-Ih\Ims , 7 5 ('iv- vi.mslt in noMilo-fi );;)(>>, ifi* i nil s jhrloiiiiig 10 t <-,u s .,!;* iiu l. i\>ti w>tti >t ih/st i jt fn,\'tn iiti l- f lAjK.siiH', IK million jnii thlfN pri rnl>n- loot tfO Million (i.nlich- l<7ll\ 14)!l 4J. /*')'.( mm tin n{. ToU-lUri lnjov , H>1* i'll uiKs, ngM, Mail'll f0'2. < mopfiimls. {t\ \ t luu kui^ tiuit tititu rnogti $> .1 s t ,n - pi Milml i 11- llnrV. *}0om. lU^moi-.i, 2 to H tMih MImim) lin^i ! -jnOniu l" 'll * J IIIII tint <H III*till I , ?(> I III'I!<'>, \\ . itin )lt >l||ttl^. pM ''' 'in', ) 0 SJ 1`iiKr i .Ur, 72, K\ mid UN; v i.ill-, M, a ml 21 <l 1 /ill/i, mix) 2 minoti-s ufti-t I(((k (<<<.(! nrit'i'i' |sU. I'uinnt intu- jih-fri) iiirll half of |him (Aru-iM1 lApUM-onti, l u li SiinnMi> -'iijiirulmt irmu<l< l l `mi i.iti-,- tirunt oVi Molli longs on ipijit Mlr.t amf jn-M'isl uttri tongM; 'i \ tmvnl tingri nail-; 3 1 mg mIo.-i jm-i 100 rr J'}U'I'lIIh n /7<mm <m ujmj. t -if l t-nlr if iMui>lniii-in mn\ i s mmr (n-* lv t lout i tgltl; 'i | luitilA- tloM of I'M 111 MUM, i--)H<llUv Mil 4lf*)il \ -/'/>/ SfiMll 'i m i muiJ ifi gn-c gltnmtlnla-- aptu-silJiliiV nMMt-t attliji ll-'itnl ln nt (Mi)mm<MIC m,u >> If ((Imi CellOVI* JM V|<MII<||'| UIH'` Ilf Of>MI->l'i III if** lltlM'f of an>l f>lnt|gi |jm ;ii uiut of fu-iut sliutfnsv. f>mymiAj( A-Mr-toM* 3 imniti'mlrU n>li iiMi't-il) FlOUHE 4fc -MOlJtflATILY AONC(D ASBESfoSIS W.ll re MAeE. AGE 40. Occf<(//ttnmal hosUtr/f. Mull- MpiniKT lust 13 yrm*, mmdu.-Ay lru<ls, IS7iy\/ir-`inuns,ilni >hmI*t* ty/foioirxat.ire. fit) Wrixlihit >vsvm<' 13 5 iiulliiin jmi 1 ic'i's jht cmJiu: ftm*1 |fif Million ji.nlirlo ymr^, 175,7. f'mt mnitiitf liim*ui:(i nmf jmiuiiMoum, mill. I'fiMjnrnt iti-aititinK colilt. < il Noim. /'fnj.Mrnf </oomi(nni htlwimiimti' ssliiO- mule Iiurln--; 155 (hmiih)'. Inlrimnlmtr < v\juui>0Mi, `J inclii'v Pry, iiiu-ii'nl ovn Iju-i-s of lon^-. I riimiy hilii'ji, f* 45 mg jwr 100 ce. ('it-lioiir onl|>u(, K0 mgj. Njttililiii nnt c\uotinrit. . l'iuinosc,if>ii ,S)imt<-i| r-ti^lit liinO.-Oi'iii of iliv|ilniij>iimUi. (`\ritr.-ion ligtit uml Ivfl is (III III-I -ili'gM'r Ollfil-C gMi0li(f ^i)"i ii)i|K ill aih'm of I fa- tmi|' lii'lilX-MM/ SUiv\> lit'1-ili'Kit't' gvtvmtiitt' up|n'(iinot ulilitiitittni' Do- Imtur iimiioin-.. Il Ifm <im* ri-(irul)u fifuo-i> u--<-/.ili-if uifh ffn* viniiiii'ttm unit flu' li-mli-ni i to Ik- mo t itciisi' ui tlio lm''i - of (lu- iooti.i. ihUtfHOSt.1. AhlM-Nfo-i- 3 . Ml -V ` I"--**/': r S VI tt p" zx 00 o ir O. i-- 11 VpkHMH FlGliHC 47,- Moot HAlELY ADVANCED ASOt i> IOSIS. WHITE MALE. AGE 49. Ocaijhilunutt Ai.s/o/ // Mule sjminrr (uslaslos), 2.r> yea is, vvoi king 10 to II limit.s u ility ; numitidv ttmivs, 0 )t'>iris timtl, i( ifuit (<j) Wrighlril n\ tTit|*<, 7 0 nilihoM |>urllrlrs |n r rulnr fool (h\ Million piilllilc yruts, 7*21.2. t'n^l imilunt 'l \|ilionl fi v*r til ugr of II Inflm-n/u, li)IH. I>r>' plniri-->, right in 1031; srron.l ullmk in |03.r mi lift. Mou: limn uwtuge munln't of chv.'t rohhraih voir Knlury rolie, 1031. t \in< jiht t uls. Slight 11 \ '>(< mu , rs|Hrinllv in rlnul'ing shuis. Slight morning mugh |>.i O 2 (o .r> s i ill m |M oiliif 11\ r of small aiuminl of ss lulr fi ol hy -jmiI iiiii. / 'hijt.it ill luiiitiiuuho/i 1 nil, ftiiily u rll <|s rfo|>ril limn f feight 70 im lif*. am I w rigid, 172 ))unml- Hluoil |n-.siur, 1 10/HO i alf, HO, 100 ami K0, rrs|tr- aloi \ i;il i', 21, 32, ami 21 (h-s|m-< livrly Infoi r, iininritinOls aflri, ami 2 loinnl <-> ii((i i' (iiiii I lomtl issui'O 0 -11 < 'lir-<l ts long, anil w rll ilr\ rloja-il \\ it 11 iiiinr ||,n mg of tlir ru->l,il maigins f'lir^l r\|>uiision, |iurhr-. Nunn mm riiiikhng lairs ill l*asr-> mi ili-rn liirulhiui' mnl after Cough. Sputum (single s|>eenrn) \\;t> t i <K ii I i v < - for u ill fa-1 I nif 11: v I uIii'mIii-im Imilirs. I'linaiv Mina, 32 iuk |hT oil M- (21-hour output, 2i<i ingi /'/miinM'ii/iv fhaphiagm jiImi>-- ( flM'iluml lung fields mlripictrd -lioWing it lii l i|i (iirr gtoiiud ghis- uppruiaiire \ uni Noli- (In- line gi.uny or gionml-glu.ss appcarnmc fanly well Innidd- In (hr low rr IuoIIokI- of eneli lung lirld. f0a/m>.M> - Ashcstosi.s 3. MODERATELY ADVANCED ASBESIOSIS. WHITE MAl.E. AGE 39 FlGUHE 40 OccufHitiomtl history. - Itruudrlolli loom room (aslHados), ll'yrn*; iimidfiaty ral-d'.rsstt,m7ulvl <i1timdu. st ( j/Mi.iioi. -lii) Weighted average, 411.7 million particles |ht aihir foot. <M Million years, I/V0.7. fast uuitiiul. Ihluleial |inriiinoinu as u child. Sinus disease for Hu* pud 2 /rail Typhoid fever, 1011. I'ottifdmnlu - Ihv, harking, morning rough piodmdiw: of 2 ounces of white, /i>t il sputum, past 2 yeats. Shortness of hreuth, 2'j years. 1`hyshnt i lamnmtion I'mrly well-developed, hfrnifrr, white man. Height, 72 nrlirs; weight, Kill pounds lilood pressuir, 101/70. I'nlso lain, OK, 70, ami OK. fd-spiiatoiy lair, 21, 30, am! 30 (iafoir, uoimdiad ly aftrr, ami 2 tmimd* Jifhr Miirlioiial i'Vitum: lr.it). ('lir-,1 ^ long, rlnuliT t>|r l'\|iun->imi, l\ inr|ir. lirart .soumil arr ilisl ant wit 0 a jniliuoiui' sirroml snuml soinrw hut hi ci ut mil i ll bliiniUM*/*y - iVakmg of I1 Imploagm luitli biiU'b. 3 cm rM-uision U)>mi forinl irs|ination , X-rity Nolr Ihr ili'fonnil \ . il. t.|iriigui 'I'liis rnsr is Uu; onfv one showing ihlinil*' ihfmnnlv in Ihr gioii|> Ihr lung tirht-> sxrrc iulrr|uclril as showing M'l'oiul-ilrgii r iliifiisr giiiiny m gionml gills* u|i|iraranr<- uith ruijihysi /nu, ,,m.............. M.wl..i-.,li Iv iul\niti'i il aslii stosls (u.sln'btosis 3). (> FtGUHE49 --ADVANCED ASBESTOSIS. WHI IE MALE, AGC 44. Occui>u(tonnl hmlury.- - Mul<' spinner (al>ealna), 171* yrurs (l(i years in stunt! room w ith tnr<ting machine*; f t ycura he worked 1 l horn* a tiny; nondn*ty trades, 17 ywis Kslmuitut dual tXfiunutt - () Weight*!*) Hveruge, Ul U million particle* j*er ciihie foot (A) Miltioii particle yearn, IU3 8. /'a*( muticul I'fftjueiit chest cold*. Acmphagia for several yours. Mnhtriu aboui 1 tnlhivn/ii, 1929 nm| 1932. < 'initftlio/ila. t'ough, I* years* tinration, possibly somewhat improved since UuiMmg work in H.sho;.fn Severe paruMsms of cough in morning, causing him \ i.intl fnipicntly uud productive of sundl amount of tenaemos mucoid sputum. Moiit'iulo iivh|Mi(H-u since 1928, unchanged. Host 15 to 20 pound* m weight itntl tt.i-.oi--utli it weakness before i|nitting work art asbestos. I'hifsinti rxuiuniniioii ' Slender fairly well-developed uud nourished white mule Height, tH inches; weight, 131 pninU. Hut her long nuiimv chest. Clu .1 l*.- uulu-s Tactile ami voice frcuudu* apjnin-ntlv nonuul. Slight impaired rcMiimuce lower huU of eneli lung. Numerous persistent tiry nnrklrx moilly over lower |.*itiniis of lung*, J'nint breath Himmia lower one- luilf light and h-ft; i ) no nv finger nails, Illood pressure, 135/Hf). l'ulsc <>i.it u-.jiiintory rule, rrspe. t*^*1 x, 72, 100, ami liK ami 2H, 32, am) 2*1, (hc/orc munediub-Jy after, ami 2 minutes after the functional exercise lest). Moderate dyspnoea following tins evereisv Urniary silica (single specimen), 2 tng per 1(g) cc Sputum negnthe for nruffa-d bacilli and iisln-sln-sis bodies. I tm/tt/mt/ft// - 2 ) lug of iliuphruginatic excursion right un*l left, ltalhcr poor rinholuco.iu'V lower lung fields A ;Hi/ Shows M-vnm(-<h'iuee grainy appearance with almost complete obliter ation of linear markings. 1 h-nejnlm-d lihrosi.i `J f-. -- Weli-esfuhlisherf asbestos)*. FIGURE 50--ADVANCED A$&$TO$JS. WHITE MALE, AGE $5. Occupational kintory.--- Preparation department (asticstng), H year*; mmduaty traldUeistm, 2u7itytieadrusa. l tJjHHurt -- (a) Weighted average, 38 0 milium particles per cub/*ic*<fouont.-dia(i6l.) - MMilaiuxmillaprayrstincnleisyee* adrrsa, in51e5d. in 1930. Typludd fever as a child, fVnnphiiMa. Dry cough. Id years, productive of 2 uuuct^ of white, thick sputum out a period of 21 hours. Uulhe.r severe dyspnoea, 3 year*. He most walk very slowly to prevent dyspnoea. Occasional edema of auktea for the past 4suyrfie''fu,ity.I-xVi.iinfTdtlr.rrtMu'o<ddeurartl.e--arHteeriigoshct,lelrioflsiinsc. heJsh. dseWreaiignh, t7,21, 3820,paonudn0d8s-, fllnod pres Uespnatory rate, 3H, M, and 51 {latfore, immediately after, am) 2 mmole.* alter lumlinnut t'Ki-rcisc test). Patient stopped on ComptcUmi of shoot nnc-half of prescribed exercise, but cvprc.NM-d u willingm^s* to continue. Chest expansum, 2 inches. Hrealhing is hltor*<l ami shallow. Prnlouged expirulion. l-'ioe crackle* apfiear </vi?r the lower half of both lungs after coughing. Heart is enlarged to the hit with the aortic second sound somewhat more prominent than the imhuonfc second. I'irot sound at the apex is split and is particularly snapping elsewhere; 2 ffficurr*visnrgupnjf/ th--e/tfuinrgtlerMrutiwiilnt< W . iluly whhwd. The cardiac shadow shows 1 | increase <n sue, Imphit1(,m i>r*huttTy breathing moves a si-ant I cm; 3 CXU-i rOmh/l.o--uSehdoCwAsCUdOilsltiOiHUt.; ground glass ap}M'arancc. tim tly linear innrl>inxn have Ihyh obliterated. liutyt4m.UaUta---. -:iHA--d--va7nced asbi-.vio*i*. Note thut moat of Die <b>< fi8 INCIDENCE OF ASDKSTOSIS Preceding sections of this bulletin have stressed the importance of the X-ray findings in establishing a diagnosis of ashestosis. '1'he reason, of course, is that X-rny examination is the most direct menus now uvnihihte for detecting the primary effect of inhaled asbestos dust on the body; namely, initiation of inlerstiiial fibrosis of lung tissue. Classification of ashestosis into a series of stages which follow one another in their development is a difficult matter because it depends to a great degree on the interpretation of relatively minor changes in the lung-field markings. Other investigators have encountered tho same difficulty. Lanza, McConnell, and Felmel (17) ami Fulton, Dooley, Matthews, and llouU (15) set up n category of doubtful cases of ashestosis. Stage ( in the accompanying tabulation more or less corresponds to their category of doubtful cases. It comprises eases in which diagnosis rests largely on X-ray evidence. Stage 2 represents early cases of ashestosis, and stage 3 designates moderately advanced eases. More advanced cases (stage 4) are relatively infrequent. Stage 5 was reserved for bed-ridden cases. Taulc 41.--- filiation of asbestusts to tuny-fithi markings fltiUHB M.~ASBESTOSIS WITH FlBROlO TUBERCULOSIS. WMIlE MALE AGE 38. On-uf>tt(nnitit history. -- Male spinner (abltcstos), II ycrurtj 8 unmlk*; umnluaty liudi-h, 12 yriir. tttlttmthil <hmt txpomire.-- (<) Wci^hlcil average, 7.0 million piirlicii-s per cubic fi.-.t ((*) Million parltele. yi-uru, KK 5. I'uit i`uih<(il -Ki-ci-iv<`(| sanatorium treatment for iubcrcitlnc.it) 8 months in IIKIU llml pnrMinoniH us u i.lolil. Appcmleetoiny in (OUi 1 'o/ii/./iu/Oi, - Dry cough |mol 5 yeurs, wor.ic ut night. Slight dyspnoea, 8 years. I`hj/3icui timmnulwn -- Very thin man. Weight, 131 pound*. Hlood pressure, 100/7(1 I'uIm- rule, 72, KO, nnd OS. ttespiratnry rule, lli, Hi, and 20 (lu-fore, niiiiM diuti ly ufler, and 2 uiuiiiU-m idler fmnlmmd exercise test) Asthenic tvpc of chest. Snme deformit v of < best tine to benliosis IHivkI expunsimi, ||1< niches. Ihrulh sounds ure olighlly in< i .id over the extreme right upper. Very feiv dt v i iIi h rigid fliqou-M /ipidu |h , iliiirl. 'flu: pulmonic second bound id much gf , 11 r than the unrtie second //uorisr<ipi/.-- Diaphragm muvw freely and eipndty on both billed. On forced ri ih.juiitfyiitluiotsuiB, ex- t Mutohidocnruinte,1lynnudiivnunricgehdt uuushdc4sLcumshonwliethft.urrcblcd (ihrolic tuhcrculodiu Table 41 illustrates the relationship of stages of ashestosis to the X-ray findings. Although diagnoses of early stages of ashestosis were occasionally made in the absence of definite ground-glass lung-field markings.when e.ougli, dyspnoea, ami objective findings were present in sufficiently advanced degree, diagnoses of the later stages of ashes tosis were not made unless iministukahle ground-glass markings were present in the lung fields. The incidence of ashestosi ' p <s rapidly with increasing die-', exposure. A fifth of the workei. v. >i!i an exposure of 50 to Oil miilio i particle years, and half of the workers having an exposure of mm i limn 100 million particle years had ashestosis. In comparison wit i scn-silicosis these are exceedingly low dusDcxposure values (HU) #; P 90 The volution of asbcstosis lo dust concentration and length of em ployment, in (able 4.'f, is of great practical importance because it shows wlmt winking conditions arc most likely lo cause usbestosis iinl Iio\v Jong a period of exposure may elapse before the disease becomes evident. ! < HI K 12 Ktlulton of usbestosis lo total Uu*t exposure ` Taiii.k *iJ. Occurrence of asbeetosi* in relation to ilusi concentration anti length of employment l'KItCKNTAUK WITH. ASUKSTOSlS Oiibi ei|iosiiru, hmIIUhi iHirlitlt* |M-r mine foot .0..i*>...U.......................................................... I[OcMI.K.I^..<Il. . . . Il'irciiilncu . . , .... ......................... . MHull.| . . .... IA llci |i'i|..... Kii^l ... il'i'molHKf.. Venn ill blmlvi liul'iMry (Mn 4U 2 ( 70 0"/t H 1JI 9' II .(7 XI 4S it1; 21 .Ml in' i The, percentage. of persons with usbestosis increases grimily with mcreasing length of employment. Lunzu, McConnell, and Fclmel (17) icpoiled it similar trend; their percentage values are higher than these, '('here are two oxplmudums for the small number of persons employed 15 years or more. This group of asbestos textile factories has been in operation from (j to Hi years, and because of (ho relatively short life of the industry in (Ids section of the country comparatively few prisons have been expo d to asbestos dust for a long time. .Another explanation is suggest' h, the fact that almost three-fourths of the u inkers employed more than 15 years have the curly stages, ul least, of a disabling disease, ashrslosis. Since there is no satisfactory way of locuting ami examining persons who drop out of an industry be cause of disability incurred therein, (he percentage values of I lie foregoing tables arc neccssurily minimal cstimutes of the prevalence of nsbesiosis. 91 The incidence of ashestosia increases with increasing dust concen tration. In (heir report of a similar study carried on in fViiiisyfvuniu asbestos textile furlorics, Fulton, Dooley, Matthews, and lloutz (15) found (hut 8 percent of the workers exposed to an average dust con centration of 5 million purtieles per cubic foot had usbestosis; 22 per cent of (be 17-/ndimn-partic)e gjon/j; and 57 percent of the 44-iuillioii- particle group had usbestosis. rilKSUOM> (.'ONITNTUATION OP ASUESTOS OUST From a practical standpoint, one of the most important results ol a medical and engineering study such ns this is the definition of safe working conditions in the industry under study. Ideally, a threshold concentratiou ol dust should hu (ho highest dust coneentritlinii thut would not produce pneumoconiosis in originally healthy workmen during their entire working lilu. The chief dillieulty in this study, as in most of the earlier studies of the Public Health Service, is thut very few workmen are exposed for u long period of time lo low con centrations of asbestos dusk. JWanse of the importance of the problem, it seems lo be desirable to use such data as are at band to define tentative safe working conditions thut may serve ns btamla.ds for the guidance of fuctory managers ami engineers unt il more coinpDle data are available. In un analysis of this kind the cases thut occur at relatively low < ist exposures arc of especial significance because they indicate what iho safe limits of exposure may be. These cases must be examined i nlividually, as well as statistically, in order to be sure that there are no unusual features that would complicate statistical analysis, Jb low 2.5 million particles per cubic foot, the interpretation of laid ' 48 offers no diltieulties. None of the 80 persons exposed to dust joiicentrations below 2.5 million purlicfcs per cubic foot had it ease of usbestosis, although, as a mailer of fact, only 0 persons hud been employed more titan 5 years. Three doubtful cases of usbestosis fell in the range 2.5 to 4.9 million particles. Because clean-cut eases of usbestosis were found only in dust con centrations exceeding 5 million particles per cubic foot, uml beruuse they were not found uL lower dust concentrations, 5 million particles per cubic foot may bo regarded tentatively as the threshold value for ushestos-dust exposure until better data are available. In order to find out the levels to which Asbestos-dust concentrations have been reduced in poo lice, an engineering study (7) was mudo in an asbestos textile hictni , ,.t . I.u li dust control equipment bus been recently installed. This shm\i> that meuns arc already uvuilaldc for mincing (he dust exposure of a majority of asbestos textile workers to less than 5 million purtides per cubic foot. Tin* data of table 43 proviso n simple means of comparing nshcslosis other pitcnnmeontoses. In a puwimisly reported study of the 1'uhlic Health Service (51) iL was found thul workmen in unlhrucite mines could ho divided into three groups whieh differed with respect lo the nature o/ the dust to whieh they wero exposed. The percent' Taiii.c 11, - /'on ntug> > uvikeri exposed to certain concentration* of atbealo* duti in a sin stun h itile fnctoi n i whoc dukt control mi a.utrrtt me used to a limited extent and in factor its when effective duel control i< practiced Oust cuiu-ciHratioii IIIJJIlt/M pUltick'S |'r lullIC lottl (.iniKt-tl UHl'df tlllsl- I'iiiiUmI Kkt'h!>lv<* cinilrul ui<-iLsur>'* 1 Over id 5I..UU . 2 &l4 V Iln<lir2 1 .. . . .. ........ IA 44 Until friuii lililo 4], 1 1>I lriiu (?). ages of men having any stage of uiithruco-silieosis (1,2, or 3) have keen tahnhited separately for caeh group in relation to uvcrago dust cun- ntiHiioii und length of employment. In passing, it may ho of in i. jc i in call attention to the dilVerence between the pnenmoconiosisprodueing power of tho thrco kinds of dust encountered in unlhreeito mines. Jf one compares groups of men with tho same dust exposure and the same length of employment, in general tho percentage of men with atilhruco-silit osis increases with the free silica content. Tahlu 4.rt Percentage of men having anlhracomticotis * * Itu iIium 10 men rmmiiiu*). As in nsbestosis, the incidence of pneumoconiosis among anlhracitc miners increases with increasing length of employment. There is a much more definite increase in the incidence of anthraco-silicosis with increasing dust concent ration thuu there is in ushestosis, probably !W because men were exposed to a much greater range of dust concen trations in anthracite mines than in asbestos textile factories. In comparison with the three kinds of dust encountered in unthrucilo mines, relatively low concentrations of asbestos dust and rela tively short lengths of employment in tire asbestos textile industry result in pneumoconiosis. There was no free silica (quartz) in tho dust encountered in tho asbestos textile factories. According to table 43, 10.3 percent of 00 former asbestos workers and 378 men and women employed at the time of the study in three asbestos textile factories hud ushestosis. (Persons who were not exposed to appreciable quantities of asbestos dust have not been included.) Wight percent of the 378 workers employed at the time of study had ushestosis. This docs not completely represent the inci dence of ushestosis because about 150 employees were discharged from these factories J5 months before tbc present study was mude. Many of the discharged asbestos workers had ushestosis, as the reports of Shull (31), Donndly (12), ami MelMieetcrs (23) show. Although an attempt was made to examine us many ns possible of these discharged cases, only 09 could bo exiimiued, 43 persons of whom had ushestosis according to the diugnostic standards employed in this study. If one assumes that the number of persons employed in these factories was the same Indore these 150 persons were discharged us it whs when the study was mude, ami if one assumes (but 02 percent of all the dis charged cases had ushestosis, then 50 cases of ushestosis escaped observation. Adding these to the 73 that were found, dividing tho sum by 447, and multiplying by 100 gives an estimated percentage of 27.5. This is not an umisuul percentage value. In numerous studies of the dusty trades tbo percentage of workers with pneumoconiosis has been found to he between 20 and 25 percent. Two such studies may he mentioned. Of 7,722 miners and men seeking employment in lead and zinc mines ut kiehcr, Oklu., who wero examined in l!>27-<?8 (49), 21.3 percent had silicosis. In u study of anthracite miners (51), `The prevalence of anthraco-silicosis among the entire group of em ployees was found to he about 23 percent." Other investigators huvo reported the incidence of ushestosis in usbestos textile factories, famza, McConnell, mid Kebnel (17) re ported, "Of tho total of 120 X-ray examinations, 4 were diugnosed ns second-degree ushestosis, 03 as first degree, 39 us doubtful, and 20 as negative." The persons ho studied "were selected more or less at random from among l)ms< t .-ig more than 3 years of employment in the industry." Since Lanza did not exaintno all tho employees in tho factories he studied, pcicc/itugc values calculated from his data are not directly comparable with rate of incidence for the present study. f PLAINTIFF'S EXHIBIT 1-5 1 0 7 ^m i J)4 l'ultou, |)noley, Matthews, uml Mont/. (15) noted that "Asbestosis 'mis found in 11 persons (12 nun, 2 women), or 25 percent of ttic ox|mised group.'' iscmv-m'fcov Asutavoais in invvEiim occupations Tin* jm i t.hi of persons iilfeclrd by asbestosis varies in di/fcrcitt occupations. The numbers of persons employed in many of the occupational groups uio so small Unit motion must be oxevnsed in limbing comparisons, but (lie data seem to be of suliicicnt interest to warrant publication. Classified by departments, (bo preparation department bus Ibe highest percentage of nsbestotic persona. Curd ing is the principal occupation in ibis department. Although only 8 of (be 72 carders bud been employed more than 10 years, 20.2 pel'* cent bad asbestosis. tCleven carders bad advanced asbestosis. No other occupational group bad so largo u proportion of udvunced cases. T.iu.t - anJ I,,ge ,,f m.rk.m havmg mg to </ purtoiciit nu<( uccup<Utun * classified accord- l>`|Mrll||Ullt BUi| nwuiMtiou N'luuUt IVfwui Willi ||hphijnl injiloMs KulltlxT with HSIS|<*S| VtvIiHfutMt................................. Cm.lttfs ............................. WliiiiUrrs llllli Sllllkfl Mil'll. .. . I'i< kcr> mill jillt'fi.......................... CttlilufN...................................... B|-imiiiif. Xwl llug, uixl m >iii)iiik.. . Muir unit itiiK bpinnrf.'.............. Twitri> .................... . .. \ mu s)kmiU'[> n>ui w mmIi r- . t'otlh'Ci ................. .- Wl itVilil! ..................................... .. CIUi wr\i r->........................... 'I .i|iiiuj hiuke iimni; Hi-.ivrij Cm lii.-* .......... . ... r llll .lulu:................... Ill'll I li.fb, I nil llijrici-t. null Hill-,lifts r >'i i"vi , ml gnuiii is . . . ! II|M mill Ihlrlu V Mini 1,1 llll y. . .,,uf iiiiibiiiu |,i14lf . .. Oil in- mill othcry........................ T*.Ul .............. , In the spinning, l\\i wdg, and binding department, Ibe node mid ling spinners bare a Ingber proportion of nsbestotic persons (ban (tie aviTiige, 2-1.b percent. Twenty of (lie sixty-live nude mid ling spinners bad been employed more (ban 10 years. A (bird occupation with an excessive prevalence rate for asbestosis is elotli wenvbig, in wbicb 25.0 pencill of the workers are idleclcd. Only A of (bo 43 workers ba,l (>ceu employed more limn 10 years. 05 A.SUfcSTOSia IN OMKAf BttlTAlN ANI> JN THE UNIT SO STATIC I .an/.a (18) bus culled attention to a point of interest, namely, Unit British investigators have found asbestosis more severe mid menacing limn it was in Ibe United States. He adds that Ibis dilfcrem'o is probably more uppurent tlian real. Lynch and Smith (20) lmve cpolled 3 fatal eases whose duration of employment in asbestos textile mills was 1!}, 17, and 21 years in occupations having dust exposures of the order of dry weaving. Slock (82) reported a fatal case in a man 27 years of age who worked 8 years ns a carder in aft asbestos plant. Kgbert (LI) Ims also given complete findings of similar case itt a mail 30years of age who bad worked 13 years as a carder and who died J yearn after onset of symptoms and '.!} years after discon tinuing work. These examples of American fatalities, some in young individuals, suggest that the period of dust exposure before disability or death ensues is as short as is the ease in silicosis. Bridges (tV.I) in the factory inspector's reports of Cleat llrituin bus shown from ycur to year (table 47) that the duration of employment of fatui cases with asbestosis is only half that of cases with silicosis. Tabus 47.- Silicosis and asbestosis in (treat Hritain Thrum'll I'.l l.\ S,lions - ...................... SiIko-o with tuliertUlo'O............. AUm->U in......................................... AilWjlosis with tii(<en iifrni- . . More titan 00 percent of the rnw mineral used in the manufacture of asbestos textiles in this country and (treat Britain is Canadian chrysolite, indicating that very JittJe difference is to be expected from the standpoint of biological icaelioii in llm two countries. As near as dust concentrations in tin; various operations of asbestos manufacture of BrilDi practice can be c.oinpaied with results obtained in this coun try, no gieuter dilleiences are found limn exist in the inherent (imita tions of the dust-sampling devices. It would seem, therefore, that ijnitc negligible ddferenees exist in the muiiifestutions of the disease here and abroad with (I. ; dlc exception of associated orcomplicftt- ing tuberculosis. ) PATHOLOGICAL FINDINGS IN ASHESTOSIS Specimen lm pathological study wen* furnished through the couitesy of |)r. ,1. Kush Shull, Charlotte, N. O., and Dr. 11. K. Kasniu, director of tho Division of Industrial Hygiene of the North Carolina Slate Hoard of Health. 'll it* pathology of ashestosis is characterized hy diffuse, interstitial, pulnmmiry fibrosis and hy tho presence of ashestosis Imdias in tho lungs. UltOSS At'l'klAIUNCi; In gross appearance tho lungs vary in color from brownish to pale gtuy. Usually, they uie not distorted like silicotic or anthnuosilicotie lungs unless an extensive amount of long-standing tihmsis is present. Often the lungs am firm and heavy, hut softer areas ean sometimes he felt on palpation. Oiepitus depends on the amount of fibrosis. 'The pleura may he thickened and lihrons tags may be ' l led over the suifa<\ In the eases described in this report, (In* truing of the pinna and the presenee of fibrous adhesions arc inoie frequently found on the right lung than on the left. Adhesions to the diaphragm are sometimes presetil. On section, small, daik gray, irregularly shaped areas are seen on the nil lung surface. They are ratlin- evenly distiihuted and they me of approximately the same size. Visible strands of eoiineclive tissue of varying size nut through the hmg paunchymil, forming a mme or less legular, (ihrous network, and enclosing the dark giay, nodular ureas and lung tissue which show alveoli. Areas of wellnuiiKed emphysema me noted in (he apices and outer pmtions of the lown Jobes, u fealuie that was referred to in the discussion of the ,\-iay lindiugs. The hronehi and bronchioles appear to lie distended and their walls me often thukeiird. In one case, tins bronchiectasis is most mmked in the upper lobe, partieulmly in (he apex. Congested meas are. occasionally seen on gross inspection of some of tlie. hmg sections, 'l in y me probably leimimd. The hilar lymph nodes me not markedly increased in size. They m<; pinkish giuy and couimii about the usual amount of antliraeotic pigment found in a city iiwYllcr. MM ItOHCOl'IC ArriiAKANI K The pleura, w hen thickened, is made up of adult fibrous connective tissue cells. Tin* collagen libers Hie usually well developed mid may show hyalinization. In some sections the thickened pleura is vascular, <IH>) !)7 the hlood vessels getiendly being small capillaries. Areas of vaiiahle size, continuing antliraeotic pigment, arc occasionally found in tho suhpleimd connective (issue. Throughout the parenchyma of the lung a diffuse interstitial fibrosis is present, which vurics with the asbestos-dust exposure of the individuiit. The ureas of iihrous tissue are irregular or stellato in shape and may contain small hlood vessels. Tho cellular elements consist of adult fibrous tissue ceils, fibroblasts, some collagen, and often numerous macrophages. The strands of iihrous tissue represent an increusu in the interlobular connective tissue. The hhrosis is usually lather uniformly distributed throughout the entire lung, in areas of consideiahle fibrosis, atelectasis is noted due to the contraction of the lilumis tissue. 'The alveoli occurring between areas of fibrosis are generally distended and slmw a moderate to marked emphysema. Tho alveolar wails are thickened by fibrous tissue, mid in some sections byalinization and the loss of nuclei occur. The alveoli arc lined by a single layer of epithelial cells. The bronchial walls and the walls of the bronchioles may be thickened, and a slight to moderate lympho cytic. inliltratiou is present occasionally. The smaller bronchi and bronchioles me frequently quite distended. The walls of the small blood vessels arc thickened, particularly the adventitia, which con'uins an increased amount of fibrous tissue. Sections through emoliyseinatous blebs show a fairly thick, fibrous, connective-tissue .vali, lined by a single layer of flat or low cuboidal, epithelial cells. The blebs, mcasuiing as much as 7 mm in diumeter in the sped nens studied, are apparently of bronchial origin. Ashestosis bodies are found in almost all purls of the pulmonary tissue. They occur most frequently in tho ureas of fibrosis tir I uro accompmiied by a greenish black pigment. They are also no *d in the connective tissue about the small bronchi, in the alveolar .vails, and in the alveoli. Macrophages and giant cells uro usually p (sent when the ushestosis bodies me found in the tdveoli and often surround or engulf the bodies. These cells also contain a considerable amount of unthrucotic pigment, and (he dark gieenish black pigment com monly found in asbestosis. A brownish yellow pigment in lesser amounts is also present, 'f lic asbestosis bodies occur in the lungs in a variety of shapes. The most frequent is a headed rod with largo rounded ends. Spindle shapes with headed centers nro also noted. Rosette formation is relatively frequent. There appears to ho no iclation between the mi' t f asbestosis bodies ami the amount of pulmonary fibrosis, in one . e in which there is exceedingly littlo hhrosis, the ashestosis bodies are pmlicidmly numerous, while in another case, showing extensive fibrosis, they mo quite infrequent. Those bodies arc golden yellow in color and uro slained blue with potas sium fcrrocyuuidc, showing the presence of ferric iron. With this PLAINTIFF'S EXHIBIT !l!l slain sonic line hloc strands Imve hern noted which me a||>nirnll_v asbestos libris in the |iron^s of heromin^ asbestosis bodies. Ity th< iino of pohui/.rd li^lil, lino libels air often demonstrated in the lissm which ale identified ns asbestos. These may hr seen in (hr fieri bronchial connective tissue, (hr mtcislihid connective tissue, (hr iSZZ'iPti ABESTOSIS Fn.UIlt 12 l'IUIOMIL'Hiii-,|Mnis OF I i lit,.. <" N..U.1I.H KlUHOSIb AM) EAIIIHSLM, !'Ni SHUWING I HE PRESENCE t UlldlSI j AND I-IJNG AM, O.EFNbE """J lb S"UWN K>H COMP,,,b,,,, MAGN,t,C,,7oM ,6)ftC"ONOF * NHMAl Figure 53 -Asoestosis Body r TICAl.LY NO FlOROSIS IN 7 HI-(Army medical. Museum No i alvuhah conniciive 1 issue I'uac/. CASE H 21. MAGNIUCAIION I.OOOX. i alveolar walls, and in the alveolar spares. Tin: blue staining libers 1 (Ins ashestosis bodies mr not visihlo when viewed with nossril I prisms. Other linr crystalline niutriial is sometimes noted, rim presenee of rojiiphrafirif' tuberculosis is offru difficult to demonstrate. Unless caseation is well delined, tlm hiheirles limy l Inn je>emhle I hr l*i elopi/t*' /ihmns aims of ushestosis In ti marked til lin', il is Ko| easy in many eu~-.es to dilletettliiHr enseution from old hyalini/ed eonneelivr tissue in (he stained speemiens. hi olio of (he ease-, studied, (hr presence of acidfnst hurilh in flu? afvenfi and eoiineelive ! .or nf (hr uUrohir units without I lit* presence of oism- 101 Usiiif' ii <i*<'hritf|fi* developed hy (Ik* INihiic Health Service foe siudy- in*' the physiolo'dral behavior of dust, This method has hern described elsru here (till). All (lure siiniptrs of asbestos dlls! pro- durrd nil inert type of reaction in (hr peritoneal (issnr.. On (hr basis of (Ids response, asbestos dust Inis hrrn eoiisideird to hr poten tially harmful, especially when inhided over long periods of lime. Ashrstos dust, like tide. (Id, II), uhieh also prodiiees all inert rrar- lion, causes a dillusr, pulmonary fibrosis as has heeu observed on elinirnl mid post-mortem examination of prisons exposed to these dusts. NI.I.KCTKlr A m orsV CASK NKKOM I S (!jsc II 21 (Fill*. ii lo Vl Male, white, lined !(K >ears. t'aiiM' n/ iUnth.- -Myurai'dilia. (henintinnol hi>hnii - Woilo-d for 12 jcais in Hie Weaving h 111 < f an iid-esluis plunl. Prior to (In', lie hud uotknl in a rollon mill. Mnlinil lu.'ilot ij.- Confined to lied for Hie most pari of his lust li mouths of life la-runsc of neatness, d\spnncu, and unpi odml iv<: rough. I'ttlhnloymtl to "iiiitiloth shotted ttell-deliued advanced ashe.-dusis, e\ ideixed hy uiueh dilln.se inlemlitial pulmonary lihio.-is, accompanied ly asU^stosu hodies, eiuphisema, hronrhieelasis, and hmuehiolerlasis. ( fit'in ii nl i i'll ni i nut ion <</ limy /issue. - Sample finin rial 11 lung - ilsh !.( |areent, silii.a (Mi pereenl, siliea in llsh IN.112 pereenl. Sample flom left hmg adi it H pet rent, siliea U 7l> pereenl, siliea in usli -Ml. tit pereenl. I IOOOL *l4 Abut SlO'jlS Uuuifj ACCOMI'ANItn BV GlANI CELLS IN AN AliA OF FiniHi->to I.ijng rissut Case H 2t Ma gnificaiion 7UbX (Ahmv Medical. Museum No 52<?l/5 * Iii>ii was observed. Tliis could possibly hr an rally tuberculous infection in the jMi'inv usivc or it fouid welt he n eoiitniniiinhii^ nonpufho^euic m id hist bacillus. .Samples of thus! vmicties of asbestos (ehrysolile, cioridohlt*, and iiuiu-He I uric indited into the pctiloiind cavities of oniiien ni-s Ill-* 10:1 FiouMt 56 Case h 2\ FlBHOIIS t.i , l I urjfi PiEUHA Much Thickenii) FfwEH Imam wi me NoitooN l me Right Lung i.illtt--3V---- B i mi i nr. i PLAINTIFFS EXHIBIT f U.UML *j/ CASE H 21 SEC I It IN O..K........H....l.G.. MI LlINli MUVW4CEO A` UlMlNULO IJMUNUII AND AIM SFACtS Al U(jlH AHfcaXdvAaNnDceBdASaEsuestosis riUlUlbll. fimoUGlIUlll LUNG SllUilAN^t ANI) J MICM-NfcD PL EUMA Diffuse Ci.me 58 CASE H 21 SSUI..N OK I EFI l IING Dili I END! O cuirf S Al APEX HAIIlEM UNIIOHMCV Ol'jl Ml HI* I ED LlINli liliONUII FlUMOUS AND AND PLAINTIFF'S EXHIBIT 1510 (59) r PLAINTIFF'S EXHIBIT i510_L60) I 1IM 41 2 t-ASL M 21 Si (. I ION OK HiCMI l.imG M(J|I| MATILV AUVANCCU A:.iii i *;.i Am Ab AND LMPnvbiMA UniKOMMI.Y DlSTHlUUItO. I Mid >1 H> I lot J I I ML I im>. SI UlS I ANI.L FiCUME 63 CASE H 2 J . ,, OK LEFT lung Shows Less Inv< lvlment 1 mat. WiGMl Long Fig fa2i . I 111? n:t Cam* 11-25 <>i ttixl <>S Mali?, while, aged 27 )cars. ('mt.te uf titufh -Lnhai pneumonia. OrcttiHiIttmttl timhinj llegim umk ul age of 10 yeins. Itmadclnlh miivir (iistieslosl, 1 year. TiimI diiver, I) months. itinnilrlolh weaver (asbestos), 2 >em->. Ti nek v**r. U yrurs. Hmudelolh weaver (nslmstns), 1 j cars. Il'< <yA(d iriuyi: itual ir/xiame.- -Hi.7 million particles per cubic (not, or 217 0 million particle \ears Afnhrid hi>1<>ri/. 1'ast history negative. Hud iidlncuzu, prior to death, winch h-vclopcd into piifitiomtiti , iiv < - '.nutliontt.- KilitiM umd< 5 months and I month (lig. 0() ladote death 1 li. I !*('tt*t* ground glass which wih intrrpicted ns commencing generalized < .is Mfinal < ruuumdum.- Tit*' principal abnormalities found on physical cviuniim- liou 15 nnoilhs before (he dentil of I he patient were srcond-degiee cur veil nails, second-degree cyanosis, and decreased ficmilu* on both tlu> right ami left stile. Ttic In iii l tii/.c iiml lieu11 sounds acre normal; blmid pressme, 120/71. On exercise (tie pulse rate lose fiom HH to 1111 ami 2 minutes later had fallen to HI. The rc piiulnrv late rose on cxeictsc lumi IK tu 20 and returin'd to 22. The patient tniiI a chest nilti at expuation of 27*j inches and a ehesl expansion of 2 inches. He was it (hick-chested man (iS1- inches tall, weighing 105 pounds. Fifteen months iiefoie death this ran: nas diagnosed as earlv Usbcstosis (stage 21. I '<ilhol`Hfu id < x<tmiu<t(ton showed early ashestosis A dilluse interstitial lihro-is Willi little emphysema and iirnnchiolcrtasis and tiuuiritun nsbcslosi* bodies nils noted I.mImt pneumonia was slims n to In" the cause of <iea(h. I "In hi inti t iwnuudom / limy Itaauc. - Sample fi out I ighl lung ash 2 11 percent, sdn a 0.2i percent, silica in ash H 12 j>ei<rid. Sample fioiu left lung -ash 2.(1 pei cent, silica 0 27 pel cent, silica in ash 11 17 pctvcnl. \ HE 64 CASE H V. CHtSC uEtN,2tEN "ue'V'v.O ROENICENO- 114 ACKNOWLEDGMENTS Grateful acknowledgments nro duo tho employers mid employees of (.lie asbestos textile plants in which this study wus made for their inter est and cooperation. Howard F. Hrubnch, laboratory assistant, prepared X-ray chest films, conducted clinical ami chemical tests on mine and sputum surnplcs, collected the atmospheric dust samples used for chemical analysis, made the photomicrographs reproduced in lids bulletin, and muteriully contiibuled to the progress of this study in these and in other ways. Junior Statistical Clerk Marjorie VV. Hertford coded and tabulated the medical findings and prepared the graphs and tublcs included in (his report. Associate Chemist F. II. Goldman mude chemical analyses on samples of asbestos dust ami surnplcs of lung tissuo. 015) Fiuume 65 Casl M 25 sta.nnofHKinru.w E.hly AsuESros.s 11, form l>,str,u,m,on of Humous areas Iiiwughoui lung Suustance SKMMAItY OF MUim-Ah FINDINGS A iimliml-\timiiin(im wns made of each employee in three asbestos textile plants employing *123 men uml 118 women. These persons were mueli younger tlurn live average industrial employee ami they Innl been employed in this industry for relatively short lengths of time. Almost half of these workers bad been previously employed in cotton or woolen textile mills. Only 23 persons had been em ployed in a trade in wliieh workers are known to he exposed to inor ganic. dust, and only 1 of these 23 persons had pneumoconiosis. For this reason, it is believed, asbestos-dust exposure ran he held respon sible for the cases of pneumoconiosis that were found in these three factories. Ashestosis is a form of pneumoeoniosis caused hy long-continued inhalation of asbestos dust. The primary effect of asbestos dust mi the body is to set up un interstitial, pulmonary iihrosis. This may s``i*n at autopsy, uml reports on three eases appear in the puihotogi. . ! section of this bulletin. This type of tihrosis may also ho detected by X-ray examination of the chest. On the X-ray lilm the shadows east by this type of fibrosis resemble ground glass in appear ance. and usually extend over the lower portions of the lung fields, frequently being heavier on the. right side. Unlike silicosis, nodular fjhro.sis Ims not been detected in asbestos woikers. As in silieosis, the ehief symptoms of ashestosis uro progressive dyspnoea, variable cough, siihslernal chest pain, decreased chest expansion, emaciation, weakness, clubbed linger tips, and curved linger nails. Most of these symptoms seem to ho the result of the pulmonary tihrosis set up hy inhaled asbestos dusl, uml the con comitant pathologic changes, such as emphysema, bronchiectasis, ami hiom hiolcctasis, which can he demonstrated at autopsy. 'J'he percentage of persons affected hy ushesfosis or by any one of these, symptoms depends upon (lie dust exposure. In all cases tho pciccntuge of persons allected hy any given sign or symptom of ashes tosis is greater than in control groups of industrial workers who were not exposed to inorganic dn I \ characteristic ol ndu m i, is the finding of ashestosis bodies in the lungs and in the .sputum. Although it docs not appear from these data that a tindiug of ashestosis bodies can he used to establish a diagnosis of ushestosis, nevertheless it is evidence of ushestos exposure. <ll> 117 Only three euses of ashestosis, all of them diagnosed as doubtful or borderline eases, were found to he exposed to dust concentrations of less than 5 million particles per cubic foot. (These three individuals had dust exposures of about 4 million particles per cubic foot.) Above r, million particles per cubic foot, numerous eases of well-marked ashestosis were found. It would seem that if the dust concentration in ushestos factories cotdd ho kept below 5 million particles (the engineering section of this report has shown how this piay he ac complished), cw cases of ashestosis probably would not appear. Ii ANNOTATED BIBLIOGRAPHY To farililutc refcinice to the papers listed in this bibliography, a brief note has been appended to caeh citation which indicates the kind of information that may bo sought for profitably. So far us possible, no information thut can he gained from the title has been icpeated in the unnotation und consequently the length of the note is no measure of the merit of the article. In the interests of completeness, a number of papers have been listed here which were not referred to in the text. The papers on lung cancer as a possible complication of ashestosis arc an example. No cases of lung cancer were found in this study, but it appears that it would bo a prolitable thing to look for whenever autopsy mutcrinl is available for study. I`or that reason papers dealing with the subject have been included. SNoiNssama Kuroins 1. Aoiiuul rejrort of lltc chief ins|>eclor of factories uimI workshops for England and Wulcs. II. M. Stationery Office, tamdon, Englund. 1010. Contains a section on observations made by Dr. Colli* on the effects of exposure to asbestos dust on 40 workers ia uu asbestos textile fuclory. 2 Bloomfield, J. J , uiul J. M. DalluVallc. Thu determination and control of industrial diiht. Public llculth Bulletin No. 217. 1035. 1 geiierully-uucupted methods of dust <|imnlilicution uiul methods in use for controlling industrial dust. 3. Hatch, Theodore, and S. 1*. Choate. Statistical description of the sue prop* cilies of iionuniform parlirolutc substances. Jour. Franklin Inst. 207: 300 387. 1020. (',j v i-H slut istical parameters for the culeulation of tolul surface area, volume, ami mass of a given distribution of nonunifonn dust particles. 4. Fulton, W. B., It. L. limits, A. Dooley, and J. L. Matthew's. Asbestosis. Part I. 'I'lic collection and counting of dust encountered in nsbeslos fabiiruling plants. PeimsyIvania l>t?pt. Labor and Industry Bull. 37. 1031. Discusses the measurement of asbestos dust and its physical properties. Engineering study of four plants. 5 Hatch, Theodnie, and <' I \b.ke. The uiineralogieal com|Hisitioii of air borne foundry dust, loin hid. Hyg. 18; 01 07. 1030. A petrographic study of air borne foundry dust according to particle size. Composition of dost reported to vary with size. 0. Hurhhul, C. tt , and C. It. Wilburns. The mineralogy of asbestos dust. Jour. Ind. Hyg. 17:280-203. 1035. Discusses the composition of settled dust sumples obtained in factories manufacturing asbestos textiles and other asbestos products. 018) .. _____ 111) 7. Page, It T., mid J. J Bloomfield. A study of dost control methods in an asbestos fabricating plant Public Health ltepoitsfi'2: 1713 172'. 1037. "This investigation included a study of utmosplicrie. dust concentrations in the factory workrooms, ami a study of the exhaust systems used to remove iislarstos dust." AbllUHTOblH 8. Alwcna, W. Uchcr Asla-slusc der Lungeii. Munehcncr mod. Woeheoschr. 82: 1707 1800. 1035 X-ray and medical study of 35 employees of a German asbestos textile factory. 22 cases of aatresloais were found. X-ray examination bliowed lloceulent markings but no undulation. 8a. di Bias!, W. Zur pulbologischen Anatomic der Lungciiusbestose. Archiv fur Gewcrbeputli. und Gewcrbehyg. 8: 130 155. 1037. , A 50-yeur-ohl man employed 21 years in an uslnstos factory died of circululory iosullicicncy after seeking treatment for shortness of breath. On autopsy the right side of the heart was enlarged. There were pleural udhcsimiH. 'I'lie fibrosis seen on gross iiis|>rctinn and confirmed on his* tologicul examination was most extensive in the lung buses. Bunding ami Bygdeu (41a) have reported oil the aslrcstosis bodies found in this ease. 8b. Buresch, Amicmarie. Pueuiuonokoniose, Bcrufokranklicit und Knlschudiguugspfliclit. Deutsche Med. Wochciiachr. 57: 1100-1102; 1247-1240. 1031. A 47-ycur-ohl man, employed 20 years in an asliestos factory, sought treat ment for disabling dyspnoeu, cardiac insufficiency, and cough. Clinical and X-ruy findings characteristic of asliestosis are described in detuil. Died as a result of right ventricular Insufficiency. Post-mortem exam ination revealed pulmonary fibrosis, marked hy|>ertrophy and dilatation of the right ventricle ami little hy|ertropliy of the left ventricle. 0. Cooke, W. E. Pulmonary asliestosiu. Brit. Med. Jour. 1027 (Vol. 2): 1024 1025. 1027. A 33-year-ohl woman employed in an asliestos factory over an 18-ycar jariod "compluined of cough, dyspnoea, cxiicctorution, and lassitude. An X-ray plate showed extensive librosis, more marked in the right lung, two calcareous glands at the root of the left lung, and two small falcurcous particles in the base of the left lower IoIhj." On autopsy, dense pleural udhesions were found- "On section the |righl) lung is seen to be lihrosod and to a large extent airless, the lung tissue tieing repluccd by fibrous tissue." Calcareous masses and areas of cusealion and cavitation were found. 10. Dewirlz, A. P. Asbestwurzcu. Arch f. Dcriuut. u. Sypli. I<> 1 1-5. 1030. Description of the localization ami the gross and histological appearances of asbestos corns. 11. Donnelly, J. Pulmonury asls'stosis. Aincr. Jour. Pub. llculth 23. 1275 1281. 1033. Partial review of pu v, . creations on the disease. Includes case reports on tluee totully disabled patients taken from u series of 15 cases (4 figures -- chest plates). All but 1 of the 15 had at one lime been diagnosed pul monary tuberculosis 12. Donnelly, J. Pulimmury a*l>catosis: incidence and prognosis. Jour. Ind. Hyg. 18: 222 228. 1038. Description of X-nty hlms of 15| Asbestos workers, biliij :in - a lit I't'lufi, D S Pulmonary usbestosis llepml of u euse with necropsy hndiugH Ainer. Rev. Tulare ill 25 .11. HUS. Autopsy report on case desciibrd by W It So|ht (Aiiut Itcv. 'I'iiIhto. 22: ft71 5h4 1930) While, 30 ) cur-old limit: employed lie) Ull uhIm'sIom ciudci lit vinrs complained of dyspnoea anil hlood-tdmthcd sputum. No <'< rh t .mi'il ami X-ruved on two occasions before death wlueh irsiillttl from t.tuliui: fuilnro. On autopsy "diffuse fihn>sts of lungs in* vnlsing purticiiluily upper lobe of right and pnitiuu of upper lolie of loft; ui listed tiihciridnsr*; uslrcstusis bodies throughout lungs; few in tracheo bronchial I3 mph nodes." 14. Mllmnu, I*. INihuoimiy asla-sloshi; lit) clinical, rudinlogicul, urn) patholog ical features, ami tihMidulatl risk of IiiIhtcuIoiis infection. Jour. Iml. Hyg. 15: 155 183. 1933. A 43-year-nld mun cuipln)cd in the i-unlroom of an ushebtos factory 9 years became disabled on account of dyspiiiH-u, accompanied ly dry, irritating lough und pingrcssivc unorexiu, loss of weight, uml clubbing of (ingiTri. X-my and cimicul examination At autopsy this case was iliugimsed us "ad winced pulmonary usla-stosis, complicated hy tnlHTCtilons pleurisy." A 31-year-old vonnaii employed 2 years making u.sl*cstos mattresses liecume dyspuiH:ic, wanted, und cyaimtie. Died of inhiTunlosis. Autopsy lindiugs are presented. I I niton, W. It , A Dool. v, J. I/. MullhevCs, and It. I. Iloiitz. Asliestosis. Part II. 'Hie union and amount of dust encountered in asbestos fabri cating plaids Part III. The elfeets of exposure to dust encountered in asbestos fabricating plaids on the health of a group of Wuikers. Pcmisylvnnm Dept, f.ubor und Industry fluff 42. 1935. Hcport of u medical examination of (ili workers. Ilibliogruphy of 125 papers. It*, tiloyue, S. It The morbid unutoiny und histology of usltcbtnsis. Tubercle N: 415 451; 493 l!)7; 550 558. l`J33. Delailed description of puthologieul findings and review of literature. 17. I.an/a, A J , W. J. McConnell, und J. W l''elmel. Ftfccls of the inhalutiim of usbeslos dost on the lungs of asbestos workers. Public Health lleports Ml: I 12 1935. Iteprint No. 1005. lirief deseriplion of the lindiiigs of un engineering and medical study mude in an usheidos textile plant "X-ray lilms were made of 120 persons." IK. I.an/.a, A. J- Asbestosis. Jour. Aiiut. Med. Assoc. I0G: 308 309. 1930. brief deseriplion of some of the curly observations on the disease purlieulaily us seen in Ihnted Slates. Also notes on clinical picture uud roent genology )9. bovihctlo, Domenico ruliiioiiiiry usbestosis. Iteenrils of the Intcrnuliotiul ('oitfeicnee `"i Silieosis held at Johminesburg, Aug. 13 27, 1930. Studies and Rep. , t > s !' (Ind. Hyg ), No. 13, pp 500 509. ^idlmr'rt nbserwitinns on wolkers handling pure asbestos und Asbestos mixed with eotloii or other vegetable diibts Concludes that at least 5 years of exposure reipnied to produce pneiimuconiosiN; diieet ratio be tween ipiuiddy of dust iuhuh d und piirmnncoiiinbis Well-established case may develop in 7 to 9 yeuis and (he dibi'aac can cause death after 13 yeuis' heavy cx|H>Mirc. 121 20. f.yuch, K M , and W. A. Smith. Pulmonary usbestosis II. Incluiling the repoitnf a pine ease. Ainer llev. TiiIhtc. 23: 043 GOO. 1931. White mule, 40 years old, employed us uu msIm-mIos carder 11 years, sought medical treatment for chest puin, loss of weight (23 lb.) and shortness uf bieatli X-ray examination on 3 occasions during a 5-year period showed mottling in both lungs. Died na a result of slow, cardiac failure. On nulupsy extensive fibrosis, emphysema, and bronchiectasis were found. TiduTeulosia was absent. 22. McDonald, Sluurt. Histology uf pulmonary asbestosis. Itrit. Med. Jour. 1927 (vol 2): 1025 1020. 1927. "The iutcislitiul fibrosis is such us might be cx|*ectcd as u result of a com bination of a pnciimocuniolic condition and n chronic tiilKTculoua infec tion " 'I'he possibility that asliestosis bo lies may have t>cen of plant or unimul ought may lie excluded. "'I'he h)pnlhcsis advanced is (fiat these bodies ure portions of ut>l>CblnH fibres in the process of alteration and absorption hy hydrolysis, either by direct chemical action or by enzymes." 23. MePheelers, 8. II. A survey of a group of employees exposed to aslicbtos dust Jour. Iml. Hyg. 18: 229 239. 1930. Reports "the results of a survey of 210 persons exposed to uslaxstos dust-" 24. MurU, L. Asla-blosis and Tultcrkulobc dcr Ttmgcii. Zeitsehr. t. Tul>erk. 72: 11 15. 1935. AslK'slosis complicated by tuberculosis was found in a 30-year-old woman employed in un uslieslos factory during a 12-year period. 25. Meri wether, K. H A. A memorandum on asliestosis. Tubercle 15; G9-H1; 109 118; 152 159. 1933 A comprehensive review of llrilish studies of ualwbtnsis, including economic, miniTidogicul, and medical historical facts, main fcuturcs of the diseasu, asbestnsis bodies, correlations with dust exposure, risk of tubcrcuhoiis, preventive measures, and compensation. * 2G. Mills, It. (I. Pulmonary usbestosis: report of a case. Minnesota Med. 13: 495 499. 1930. A 58-yeur-oh| man exposed to asltcstos dust in a mine 17 years previously was udmitted lo u hospital where he died of heart block. Marked lung fibrosis was found on autopsy. Asbestos filters and asU-stosis bodies were found on microscopic examination. ' * 27. Mussu, (iinvuimi- Clinical and radiological notes on pneumoconiosis duo to asbestos. Silicosis--records of International Conference held at Johannesburg, Aug. 13 27, 1930. Studies uud Reports, Scries F (Ind. H>g ). No 13, p. 509. 'Die X-ray shows "arborization distributed bilaterally in the hilar and |>erilillnr /.ones which in must advanced eases considerably reduces transpar ency. Sometimes there is infiltration of the buses.'* 28. Oliver, Thomas. Clinical aspects of pulmonary usbestosis. JJril. Med, Jour 1927 (Vol 2). 1020 1027. 1927. Cusc hist01 n women who urc the subjects of pulmonary asliesfosts, one aged I .nil .>. other 39." 29. 1`uiuoiist, II Iv , I <i. Miller, und 11. It. M l.andis A roentgenologic study of the elfeets of dust inhalation upon the hni|'s Truns. Assoc. Ainer. I'hysieiuns 32: 97-108. 19(7. !, PUINTIFF'S EXHIBIT 122 The X-inv as|H-rl* uf 137 individuals exposed to niganic und iiioigunic dust aie pirseuted Of the ('roup exposed lo imugahic ihlst 15 nrri! usbe.stos ttotkcr.N. SlmiluHH almost invariably Inst appealed m the right hing on a lex el u it li lIn* lulus tdiudow. Tin: appeu ranee of I In- shadows is reported "softer ami less hliurply delincd" in asbestos w 01 kers. A good description ib given of (It. liner stages which I lie authors recognize in the progicss of piicnoii ii.x.i 30 iSrhustei, N.irah II I'nlmonury Ubbcbtnsia in a dog. Jour. I'uth. anil Had. :l 7.r>I 757. 1931. A dog kept in an usIk'hIoh factory 10 yeurs "had suffered for two yearn from cough and dyspnoea, and for nix mouths from progressive wauling. The d> spnoea hceuiuc ho distressing tliut lie was destroyed." On examination of the luiiga diffuse hbiusia, hroiieliiertasis, phugocy losis, and usln'tiln* libers were found. Asls-slowis bodies were not found. 30n Seder, II I'., and M. I). (Jilmoiir. A cant! of pulmonary asbestosis. Hrit. Med Jour. I0 tI (I); 1112 1114. 1931. A 12-year-old man employed 23 yearn in an asbestos factory an a carder, dry-clolh weaver, ami in the inannfaclure of mdlhonrd, nought treatment for "cough, bieathlesniiesi, loss of weight, and lassitude. Itadiograplne examination revealed a diffuse line nmllling of a Hilicolic nature hpiend throughout Imlli lungs The patient who in the subject of these notes has died, und tin? fact that pathological examination showed that death ..is due Holely to curdno . dim- secondary lo hack pressure resulting from the massive generalind lihrosis and Irre3|>ectivc of uny added infection is an additional point of interest in thin case." 31. Shull, J. It. Ashestubis: a roentgenologic review of 71 cuhch. Itudiology 27. 279 292. 1930 Hermits of iiiediral examination of uslieslos textile workers. Two uulopsy reports. 32. Stock, (I A. Pulmonary asbestosis. I2ti 129. 1933. Med. Hull. Veterans' Adm. 10: A 27-year-old man, employed K years us an asbestos carder, was admitted to a hospital heemise of shortness uf hreuth and chest pain, lit; whh under, weight and luul poor chest expansion. No pulmonary InltemdoHis present. "The post-inoitein diagnoses were: Pneumonia, acute lobar; pneumoco niosis, all lohes of Imth lungs; plemisy, rhionic, lilu inous, right, und chronic Idirimtiis with adhesions, left; Intel lohur, left; liy|>erirophy und dilutatioii of the heart; nppemln ilis, cluonic." Histological cvuminulion icveulcd asbestosis bodies und lihronts 33 Siioehe, II. KciirhL uher den I'nll von l.imgcn-usl>eslnt>iH, welcher der Albeit des Ih-1111 Pi of Heger zugiumle liigt Virchow's Archiv. f. puthologi->ehe Aimlooiie u I'li\ siologie 299: 351 3-r7. 1933. 3.ri v* ar-old limn employed in a t h i mini asbestos fai bu y 29 years complained of d>spnoea. Inmiehih . I loss of weight. X-iay examination showed ' I me, iloccidciil inui I. iiir < in niidille and low er portions of hmg fields. 1 lied of heart failure tin aulopsy, f-mnd hhiosis, emphysema, and usImjhIosIs ho<lles. No signs of tuheieuhisls. 33a White, T. 1*. I'olmoiiaiv ushe.stosis. 'I'ruiis. Med- iSoc. Stale of North t.'aioliiiU. I93.* 259 2h2. 1935. A If) year-old man nnp|u\ed 9 yeuis in uti asbestos mill sought medical ticatmcul on iiccoiml of slmrliicsd of hrcHth, nonproductive cough, and slight loss of weight. All symptoms increased ill severity as lime went nil. 123 On X-ruy examination 9 years later "The lung liclds are negative for tubciciilosis The examination shows a marked, widespread hbrosis throughout both chests which reaches the |>criplicry. Tin- heart outline is entirely obscured by dense lihrosis and the curdio-phmiic uogles are obliterated." The exuct heart measurements cannot Ihj determined lcenuse of the shtiggincss of the heurt outline but the heart is definitely enlarged " 34. Wood, W. H , and 1>. S. Page. A cum* of pnlmonury asbestosis: Death from tulH'i'culosis two yeurs uftcr first exposure to the dust. Tulierele 11: I r7 158 1939. A 21-year-old woman employed 15 months as a spinner in an asbestos factory sought treatment for "anorexia, weakness, wasting, and puiu iu llie right side of the chest of three months' duration She denied having cough nr expeetoiation. There was no radiographic evidence of pneumoconiosis." On histological examination of the lungs, "in the few sections examined in which tuberculous lesions were not present, the asliestos together with a large tpmnlity of black pigment was generally surrounded by a little libmits tissue, but there was no gross lihrosis " Abla-stus fillers and asbeslosiu bodies were found 35. Wood, W. H , and S. K. (iloyne. Pulmonary aslwslosis; a review of one hundred cases. I.amct 227 (2): I3M3 1395 1931. Of 199 asbestos winkers who nought medical treatment, 53 had uncompli cated ushcstiisis, 21 tiad uslwblosis with active tuberculiisis, 0 had as- hestosis with obsolescent luliereulosis, ami 17 were diagnosed us doubtful cases uf asbestosis. "Septic bronchitis, broncho-pneumonia, and pul- numury tuberculosis are the coimimncst teimiual complications of the disease." ASHKSTt hSlS HO OIKS 39. (iloyne, S H 3'lie presence of HHlicHtosib bodies iu the faece in a case of pulmonary librohis. Tubercle 12: 158 159. 1931. "The fueees were emulsified with four or five times their vnlmu of 5 |>er cent foimaliii iu saline. The emulsion of the faeces, when ccuirifngcd, was found to contain a scanty imudicr of asliestosis Imdies." 37. (iloyne, S It. A method of staining the uslies^osis bodies (omul ill the sputum of asbestos workers. Jour. Ind. llyg- 13' 85-89. 1931. Describes teclmiipies employing Prussian blue and auiumniuiu sullnle. 3H. I.ynrh, |\. M , and W A. Smith Aslwstosis bodies iu sputum and lung. Jour. Amcr Med Assoc. 95: 959-991. 1939. Asbestosis bodies (illiistrulcd) were recovered from the lungs of two asbcHlos workers and from the sputum of four asbestos workers 39. Page, It A study of the sputum in pulmonary usbestosis. Amcr. Jour. Med. Ki i 189. 41 55. 1935 Clumps of asbestosis bodies were found in the sputum of 19 usbestos workers with advanced a b .losi.i. Asbestosis bodies were found in ull but I of the 31 cases .1 , 49. Nleuurl, M J.un.iA < lladdow. Demonstration of the peculiar Inidies of pulmonary u-ibesln.-.H ("asbestosis bodies") in material obtained by lung puncture ami in the sputum. Jour. Path, and Had. 32: 172 1929. Asbestosis bodies were found in material olduiued by puncturing the left lung wi(li a hollow needle. Patient was a 3M-year-old woman, employed in an usbcslos factory 15 years, who had cough, dyspnoea, ami loss of weight. 'm >'iw M PLAINTIFF'S EXHIBIT ISIP f^ 7 J 124 II. Stewart, M. J., N. Tuttcrsull, and A. (*. Iluddow. On the occurrence of i lumps of UhlicHtiihiH bodies in tin- sputum of a.slK'htoH workers. Jour. Path. Hul l. 35: 737 711. 1932. A clump of usIm-oIomh lM)ili<`8 hum found 111 tlir sputum of a 31-yeur-old wouiun employed II years in an asla-slns factory. Slie complained of dvj'pnocu, ami anorexia. "The radiograph showed ddfuse line sli --o H" -oglioiit the lower third <f both lungs." Died of bronchopin uiuoniu. On autopsy, "There was noluble dilfiibe fibrosis of the gicutrr (laoml) portion of bolh lower iola-s. The uou-liliroseil tissue wusaomewhut eiuphybeiimtoiiK." Asbcstosis Itodies were most numerous in the densely fibrosed arcus. No evidence of tidierciilosiH. 41a. Snudnis, N, und A. Bygdln. lh?r Staubinhull einer AsiM-hloKiHhiugc und ilie lhrschaifcnhcil dcr sogenannlen Asbcsto.sihk<ir|>crchcit. Arcliiv fur (ewerlM-piith. und Gcwcrlicliyg. H: *20-70. 1037. (pmnlitutivc inicroehcinicul analysis of asbcblosis bodies isoluted from a human long showed that the gel surrounding the usliesloa tilier consisted largely of ferric oxide, phosphate, an orgunie subbtunee w hose chemical eompobition buggchls that it is u protein, and wutcr. ('hcniical unalysis and X-ruy exummution of cores of asbeslosiN bodies indicated that the chcmicul composition of the asbestos fiber remuined unchanged. Olllfcll I'NKUMoCONIOhtS 1* ('urtis, A. J. It. The hi-ullh of cement workers. Indust. Med. 0: 105-200. 1037. Itesults of a medical survey of 201 men exposed to dust in a cement mill. Morbidity data for 31 plunts. 43. Drcehsrn, W (*. Effects of certain silicate dusts on the lungs. Jour. Ind. Ilyg. 15: lib 78. 1033. "The siliente dusts of tieinolile talc and slate induce a fine, diffuse, biluleral fibrosis of the lungs which is definitely demoiibtrahle in the X-ray." 43a. Dieessen, W. ('. Effect of inhaled marble dust as oliscrvcd in Vermont marble finishers. Public Health deports 40: 724-732. 1031. "Allhongh marble dust when inhaled in the concentrations here observed I less than 2fi million purlicles |ier cubic foul| produces a mild bilateral, linear fibrosis in 115 percent of (lie 80 men X -rayed| no serious lung changes weic noted and there wus no disability due to the dust, even after many years of exposure." 41 Ihrrbhcii, \V (J , ami .1. M. IhdlaValle. 'The elfects of exposure to dust in two Georgia tulc millb ami mines. Public Health Itepoilb 50: 131-143. 1035. lb-punt KiliO Engineering and medical study of the relation between dust cx|Hisurc and occurrence of pneumoconiosis in lilt workers. 45. IhccHscn, W (', and It |( Jones. Anthiiicnsilicosis. Jour. Amcr. Med. Assoc 107: 1170 iio< I934> Itesults of a medical examination of 2,711 employed and 135 dibubled anthrui ite miners. 40 linlfmun, I- 1.. Mortality from respiratory diseases in dusty trades (inor-* gunic dusts). Hull. li. S llur. I.nh Slid. No. 231, pp. 170 180. 1018. Gms brjcf buminanes of the clfccls of exposure to inoigunic dusts, compiled frum occupational mortality data available in 1018. ]L5 47. Middleton, K. I.. Industrial pulmonary diseuse due to the inhalation of dust, l-uncel 231: I I); 50 01. 103(1. Part I deals with silicosis, Part II with silicatosis (including adiestosis). 48. IfiiHbdl, A. E., If. II. Itritten, E. It. Thompson, and J. J Hl ioiiifield. 'flic hrultli of workers in dusty trudes. II. Exposure to silieeoi h dost (granite industry). Public Health Ihilleliu No. 187. 1020. An engineering, medical, and statistical study of the effects of exposure to granite dust on woikers. i 49. Buyers, It. It , V. V. Meriwether, A. J. Eaiizu, and W. W. Aduma. Silicosis und tulierculonis among miners of the In state district of .................. .. Kansas, and Missouri. I l or the year ended Juno 30, 1 *28. Bureau of Mines, Technictd Pu|er 545. 1033. Itesults of medical und roeutgeuographic examinations of 7,722 men employed in lead und zinc mines. 50. Sayers, H. It. Silicosis. Public Health Reports 49: 695-ti*)2. 1934. lie- print 1020. Discussion of the historical, medical, and engineering aspects of silicosis. 51. Sa>ers, U. H., J. J. Bloomfield, J. M. DtdlaValle, 11. U. Jones, W. C. Dreessen, I). k. Brunduge, and 11. II. Britten. Aiilhraco-silicosis among hard coul miners. Public Health Bulletin No. 221. 1935. Medical and engineering study of incidence of pneumoconiosis in relation to dust exposure uiuoug 2,700 anthracite miners. 52. Thumps...... li. It., I). K. Brunduge, A. E. ltnssell, and J. J. Bloomfield. The hcullh of workers in dusty trudes. I. Health of workers in a Portland cement plant. Public Health Bulletin No. 170- 1928. Includes an engineering study of dust conditions in a cement plant, records of respiratory uilincids, and physical examinations of a large group of workers. CANCfellt AND ABBKSrOttlS : 62a. Egbert, D. S., und A. J. Geiger. Pulmonary aatiesiosia and carcinoma. Amer. Uev. Tidierc. 31: 143 160. 1930. A 41-year-old man employed 18 years as an asbestos weaver sought medical treatment for dybpnoeu, cough, and "ait insidious, gradually increasing pniii of aching character throughout the hack." Patient lost 40 |K>unds within a few months. Before death, X-ray and lulmratory tests were made. Besides Ibe cliaructeiislic puthologicul and histologieal signs of iislH-btosis, lime was u luige piimary carcinoma (illustrated) in the lower lobe of the left lung. 53. Gloync, S. It. Hiiutmiuiis carcinoma of lung occurring in ubltcstouis: two cases. Tulmcki 17: 6-|0. 1935. I)c.s( i iption of umligiiiint lesions noted in two cuscs. 'Che lesions were sifiall und not iccnguued in life. They showed prickle cells, kcrutiiiuslioii, and cell nests. The growths udvitueed along the bronchial mucosa by Con tinuous fii i- Id piolongalions. 'i'hc growths were in a portion of the lung whoe i 'i i.istosis was ipiitu udvunced. 54. Gloync, S. It Out cell carcinoma of lung occurring in uslieslosis: case. TnhciclolH. HMMIII. 1930. 'I'ypicul, extensive a.sbextnsis was found on autopsy of a S9-year-ohl man employed 22)2 years in the storage dipurtment of an u.ibcstos fuctory. A neoplasm about the size of a golf hull was found in the peripheral portion of the lower lobe of the left lung, continuous with the pleura. The growth 'Mir- soft, pinkish white, iiimI fairly wi ll demun uted. It gicw outward finiii a center m a compart iiiii^, destioying lung iivnie ns it piugrcssed. 55. I.)mil, K. M , mill VV'. A. Smith. ('auimimti of lung in aslichtn-uilicnsis. Amir Jour, ('uncer 21. 511 (il. 11135 <'iisr report of while mule, ugc 57, who huil lai n rollon weaver 22 years anil " ra' . I i -i mill about 21 years As result of exposure, lie Imtl nt* 11 -1\ - nhro.i ! lungs uml pleura "ilh eiuphi seina, bronchiectasis, unil ciihliiii' i nihuiiii'.biiu'iil, )ii mhlilioii lo the diffuse fibrosis, the authors unfed foriiiiilion of hyalin fibrous nodules ehuiarInislic of silicosis. The pulmonary lunrrr appealed to otigiuulc from our of Iho blanches of the biom-lnm to the right lower lohe, where sipiumons metaplasia of the living rpilhrliuin "as ohserveil The tlnrnlinn of the cancer coiihl not he spccilieil, hut it iliil not anlrilule the fibrosis. Mlsrtl.I.ANKOUrt 50 linden, Hollo II , ami I. It Thompson. A health slmly of len thousand mule imhn-tnal workers Statistical analysis of surveys in leu industries. 1`uhlic lleullh ItulU tin No. 102. 1*321). Suinmury of anthropoinetite and physiological data obtained in physical examinations, together with incidence of ceiluin physical defects. 57 (lunhuT, L. II , and l> I' t'uininings. Studies on experimental piicumonoI oiiiosis. VI Inhululii a of u.sheblos dust: I Is eircct upon primary (iiherculoiis infection Jour. Ind llyg. 13: 05-80 97 112. 1931. "(iumea-pigs have heeii exposed for eight hours daily for periods as long as two and one-third years to an atmosphere containing approximately thirty-five million particles per culne foot of asbestos dust (('anadiun chrysolite) l 5 microns and less in diameter, tlahhits and ulhino ruts have likewise heeu exposed for shorter jH-nods (330 days).*' 58. (iloynr, S. It The piesence of the usheslos fibre in the lesions of asl>estns workers. Tnbeicle It): -101 407. 1929. Asbestos fibers, but not ushestnsis bodies, were found in astiestos corns. 59. King, 10. J , and M, Ihilan Sdiro.xis and the metahobsiu of silica. Can. Med Assoc Jour 31: 21 20 1931. drmury silica eoutcut of 50 miners was 2.2 mg per 100 ce; of 1U stmlenta I mg per 100 ce (single bperunens). Analytical prueedure is dcscrilird. (ill. Mill.:!, J VV , und l( It .Sayers The physiological response of peritoneal tc.->ue lo cvitiun mdnstiial and pure inmerut dusts, i'uhlic llcultb Ib poits 51: 1077 1088. 1930 Kepimt No. I7H7. 32 dusts were classified aceoidiug to the leaction produced on iutrapei itoncal injielmu into guinea pigs. (il. Milh i, W S. 1 he iiing. (diaries 0. Thomas, Springfield, 111. HaUimorc 1937. pp. 55 1'' Non is, ti W , und II 71 l.andis. Diseases of the chest and the prill- <iples of physical diagnosis, \V, II. Saunders (*o,, IMuladclpliia. 5lh edition. 1933 ti.l l.xliacts from the unnunl teporl of the t'hicf Inspector of |''aetories und Woikshops. 1935 (.haplcr III -Health His Majesty's Stationery | )< pi |.oinlo|i. o