Document 3JVEqj7aoKooe2BBJMKQgRaxy

ATTORNEYS' TEXTBOOK OF MEDICINE Bj ROSCOE N. GRAY, M.D. Surpad Director, Aetna Life Insurance Company Hartford, Connecticut Aibaxt, N. Y. . SIATTHETT BEXDEft COMPACT OTOORPORATED 1934 ' I 4 Cormcar, 1934 By MATTHEW SENDER & COMPANY Copyright in Gnat Britain ami in the Brirnh Dominions and Powomoo* All right* reserved < a Third Printing Mated in V. $-A. _ Gray Aity. Testhk. Iftil XS3ZST0SIS Asbestos particles inhaled into the lung produce an exceed* iagly severe and perhaps fatal inflammation. This condition, called asbestoss, is not so important as many other forms of .mineral irritation of lung tissue, because of its infrequency. Bowrrgr. it will become more prevalent as the industry grows. Care must be exercised in the event of claim, that the dis ability is properly chargeable under your policy, that the cost should not be pro-rated with previous carriers, and that the diagnosis is correct. Since asbestosis is incurable, and usually results in total permanent disability followed by death, care and caution should be used before a claim is assumed. ASBESTOS EXPOSURE IK INDUSTRY Asbestos is rapidly coming into use for a great variety of articles, particularly due to its heat, chemical, and electrical resisting qualities. A list of these will indicate that exposure may appear in many industries: doth for theatre curtains or scenery, and for suits, aprons, gloves, mittens, leggings, and helmets; paper for filtering strong adds or bases, and for lin ings between floors or on pipes; as a thick paper for linings of stoves, furnaces, heaters, filing cabinets, automobile mufflers, and electric switch boxes; as a cloth covered with rubber cement for gaskets; woven with metal for brake linings or dutch facings, and braided or woven tape; for non-inflammable rope; as millboard and shingles; and mixed with Portland cement as fireproof shingles and building material. Fortunately the manufacture of many of these articles is not accompanied with a great deal of asbestos dust, which is the only form in which this substance is dangerous. After refinement and the pressing or weaving into cloth, tape, rope, paper, or sheets, there is usually too little dust liberated to do much harm. TCe may, from a practical point of view, elimi nate all plants as potential hazards in the production of ashes- 2S Asbcstosis toia except quarrying, cleaning, spinning, weaving, and press ing of this mineral. Although asbestos has been used since antiquity, asbestosis is a distinctly modem disease, the first known case having occurred in 1S99, end only two were reported previous to 192S. How does it happen that apparently the disease did not occur before? Just as with silicosis, considerable of the mineral must be inhaled, and it was not until the advent of machinery that mffigjitnt. dust was produced. Particularly in the carding of the fibers, preparatory to making thread for weaving doth, tape, and rope, enormous quantities of dust fiy about. More over, in all other stages of manufacture by machinery until the fibers are imprisoned in some permanent fora, the hazard is exceedingly great, unless the highest type of exhaust ventila tion is employed. The hand processes in use until recent years were too leisurely to produce many particles. COMPOSITION OF ASBESTOS Asbestos is not a single chemical entity. The name is given to minerals that can be easily separated into flexible fibers. They are all silicates, compounds of metals, silicon, and oxygen, occurring principally as hydrous magnesium or calcium sili cate. Specimens from different parts of the world vary widely in formula and in physical as well as chemical qualities, giving rise to many different names. It is not necessary that you should know them apart, since all are apparently quite poison ous if inhaled in sufficient quantity. The names of the com mon ones are given that you may recognize them as asbestos, and not be led astray, thinking them to be something else. The Canadian mines supply the bulk of the world's supply under the name chrysotile. or serpentine. Chrysotile has a particularly long; strong fiber easy to spin, but of little use as a resistant to acids. The Russian and South African amphibole, or homblend. is poor for spinning, but makes an excellent acid resisting filter paper. Crocidolite and amosite are asbestos found in South. Africa containing much iron silicate. TremoIite from Italy is largely magnesium silicate. Many local .Asxcssosts 29 r--I have been pvo, as mountain flax when the fibers are particularly silky and flexible. When ckedy interwoven, it ^ .retimes called mountain leather, mountain cork^or moun- paper. That `with very fine flexible fibers has been called flexible asbestos, amlantus, or amianthus. There many trade wanes as uralite, salamandrite, asbestolith, ; gypane. They ore all asbestos. PROCESSING OP ASBESTOS Asbestos is usually quarried although it may be tunnel rimed. especially in Arizona. After dislodging by blasting t:ui dynamite, the best, long fibered pieces are separated with snail hammers by hand. This process is called cobbing: If wet the ore is dried. Then it is crushed by rock breakers, zmd finally divided between rollers. Fiberizers tear die fibers opart. On large screens, it is automatically shaken, with sepa ration of sand or dirt, and graded by rotary screening. Then it is bagged, and ready for manufacture into the many, final products. The process of cloth making is very similar to that followed with cotton, necessitating carding, spinning, and weaving. The mar. cture of paper, thick sheets, and fireproof board is pre- '-t*ded by sorting and so called "opening up." wherein the fibers are pulled apart . DUST ' A of these processes are accompanied by a tremendous volume of very fine dust, until such time as the tiny, loose curricles have become separated, and the fibers trapped as in bread, paper, or board. Then, handling relatively harm- The greatest dust hazard occurs in the carding rooms, -though considerable danger is present until the fibers have revome bound in some permanent form. A microscopic study of asbestos and of the dust is necessary *! 2 c*S3r oaderstanding of the lung-changes occurring in this asbestos consists of translucent jdisten- A relatively small quantity of dark, opaque, angn- 30 Asbestosis jar parades are found scattered here and there. Tiny black granules are seen as integral portions of the fibers. The dust ..contains not as many fibers as would be expected, but a rela tively small quantity, while the particles and granules are present in great profusion. The assumption is dear that the dust consists mostly of particles that have been mechanically loosened from the fibers, and that but little of the latter are found, since most of them are too large to fly fredy about, or have remained stuck to the remainder of the asbestos.4 We shad find that the fibers and the black material play two different parts in the production of asbestosis. It is there fore necessary that we know their chemical composition. The fibers are silicates whose formula depends upon the particular variety of asbestos present The dark material is very rich in iron oxide and carbon. ACTION OF DUST ON LUNG Fibers may be inhaled in such tremendous quantities that actual plugging of bronchioles occurs. Examination of the lung will disclose asbestos fragments of all sizes, from very thin spicules Z micron (1/23.000 inch) in length to others extending 360 microns (over M0 inch). They are the exact counterpart of those found in asbestos dust When a bron chiole is plugged, no longer permitting the passage of air, that, part of the lung cannot function. It dies, and either becomes abscessed, or replaced by scar tissue. Fortunately, the majority of fibers are too small to prevent passage of air, or are not inhaled in-sufficient quantity. How ever. unlike most foreign bodies that enter the lung, they can not be swept out by the ladling motion of the hair-like cilia on the mucous membrane, whose function is to remove dust from the lung. Asbestos is too irregular, and the fragments usually become lodged, to remain within the lung, only to begin the slow, insriious poisoning that will continue for many years. ... ' It is not entirely clear what occurs, but apparently the following complicated steps give the best acrepred explanation a i <a Asbestosis 31 of the changes found in the lung. so far as the .asbestos fiber is concerned: L The asbestos spicule or fiber lodges in a bronchiole or an alveolus. (.Dilated structure at end of bronchiole where oxygen absorption occurs..; 2. Minute extravasation df blood or serum envelops the spicule. . / 3. The minute soluble portion, of the asbestos dissolves m f 'the serum and mucus. . '. 4. The surface of the fiber adsorbs, or holds thereto the colloidal solution of asbestos and serum, or mucus. 5. rsamii^l reaction occurs between the soluble portion of L asbestos and tissue fluids with loss of water, so a perma nent union results, coating the fiber. 6. This jelly-like envelope becomes molded by the alveolar or bronchial currents in the normal flow of mucus in the lung. 7. From time to time these u curious bodies " become loos ened and carried out of the lung by the action of the cilia. Then they appear in the sputum. i These " curious bodies " gain their name from the variety of shapes they may assume, and die fact that their nature was not at all understood for some time. A better name, of late 3 suggested, Is "asbestosis bodies." Their presence in any con siderable number, either in the sputum or the lung, is proof positive of asbestos exposure, since they have never been found due to any other condition. It is not necessary to go into an elaborate description of the very complicated steps needed to prove the identity of alleged " asbestosis " or "curious bodies." It requires die most expert laboratory work to complete this a cardinal proof of diagnosis. Since it is but rarely that a doctor a can be found who has seen them, you should consult a very 7 able pathologist, and ask him to malm the necessary testa, in accordance with technique such as outlined by Merewether ie under the title: " The Occurrence of Pulmonary Fibrosis and n Other Pulmonary Affections in Asbestos Workers," reported # 32 Asbestosxs hi the Journal of Industrial Hygiene for June 1930 on Page 239.(6) It will be recalled that asbestos dust not only contains fibers, but,that many particles are also present. They are mostly either of carbon or various compounds of iron, magnesium, or are silicates, as miea. These particles may be seen inter- spepse-j throughout the asbestos ore, and have become dis lodged when the fibers were tom apart. Thus, finished asbestos products contain but few, while the dust, especially of the carding rooms, is loaded with them. * As would be expected, the lung of an old asbestos worker contains many ** particles," inhaled through the years. Since, they are practically insoluble, they remain in the lung if small enough to enter the alveoli, or are not swept out by the cilia oi the mucous membrane. They do not remain at the. spot where they lodged, but are seized upon by the " dust cells " of the lung and the phagocytes, or white cells that act as the scavengers of the body. These ingest the particles, cfiasolve out any digestible material, and cany the remainder away. Similarly, the tiny asbestos fibers, undergoing chemical change, are carried off in nature's effort to rid the body of their poisonous presence. The " dust cells " and phagocytes do not always succeed in their task of elimination. The jour ney from the alveoli and bronchioles to the lymphatic glands is but slowly made. Many of the u scavenger cells " die on the way, leaving the ingested " particles " and " curious bodies " behind. This is particularly true where the lymphatic channels which they follow join one another. Then plugging may occur at these points, due to the great quantity of in soluble and poisonous material being carried along. So, masses of " particles " and " curious bodies " will be found hem and , them at the junction of lymphatics and in the various lym phatic glands of the lung. While the " particles " do not undergo very important chem ical changes. leading to the death of many cells, the asbestos fibers seriously disturb the life processes of surrounding tissue. Local inflammation and death result. Areas of lung am de- do. Page isfibes, : mostly sium, or n interxne disasbestos r of the i worker l Since if mm 11 the cilia the spot mils" of t as the dissolve sway mental body ofagocytes he jourc glands " die on 1 curious mphatic Bi l' nmzrinOx tv of in3, masses here and ous bra nt chemasbestos is tissue. ; are-de- Asaceroszs 33 stroked and h**l*"y occurs through replacement with fibrous ceil^ cimUnp to scar tissue. The fibrosis of asbestosis ensues. XORBID ANATOMY . A description of the lung changes will clearly explain the symptoms of this di<aa*. A complete and masterly discus lion of this subject has been given by E. R. A- Uerewether (5) in the Journal of Industrial Hygiene for June 1930. Briefly, the changes are divided into two stages, tissue de struction and reparative processes. The poisonous action of xhe asbestos leads to a destruction of mucous membrane in the bronchioles sad alveoli, as well as of the lymphatic chan nels through which the " scavenger cells " attempt to carry the dust aw&y to the lymphatic glands. Thus a chronic bron chitis is set up. If bronchioles become mechanically plugged, necessitating increased air supply to uninvolved portions of the lung, many dilate, producing a bronchiectasis, or dilatation of bronchi. Complete stoppage of air channels leads to death of that part of the lung which no longer functions. Sufficient air cannot be absorbed, so breathlessness on exertion ensues. X-RAY FINDINGS Nature tries to overcome the difficulty by replacing de stroyed structures with fibrous tissue. The degree of fibrosis will, of course, depend upon how far advanced the changes are, but the most characteristic x-ray finding is the so-called ** ground-glass " appearance, wherein the entire picture has a hazy, indefinite, fogged effect, due to the presence of fibrosis scattered throughout the lung; Close examination shows that the hnrinPM is not entirely vague, but consists of fine lines during the early stages, with tiny dots appearing later, as susses of dust are deposited at the junction of lymphatics. The dots become larger, with a coarse mottling of the picture. Finally, large masses of scar bind the layers of the pleura together, and adhesions drag various parts of the lung away frt'm their normal positions. 4 Asbesxdsis SYMPTOMS. As may be expected, the symptoms are very largely due to the destruction of lung tissue and to die bronchitis. Dyspnea, or shortness of breath on exertion is a cardinal symptom ir. 52% of cases. Cough, due to bronchitis, occurs in 39%. Be cause of insufficient lung tissue to properly aerate the blck-1. ` ' cyanosis, or -a- blueness of the skin is apparent in 56% of patients. Bronchitis accounts for marked raising of phlegm with 34%. Adhesions of the pleura produce pain in 11% on DIAGNOSIS * This disease occurs rarely in the experience of most doctors, and they usually received no teaching regarding probable find- isgs. Thus they cannot be expected to recognize a case with out special study. The similarity to silicosis leads to mistake unless great care is used in the interpretation of x-rays. Even the pictures may be so similar that the history of exposure to - asbestos or silicon dioxide must be carefully considered. Frequently the findings and x-ray studies indicate a fibrous tuberculosis, which may also be independently present Bron chitis in an asbestos worker docs not necessarily indicate jsbestosis, nor does bronchiectasis, although both are very suggestive. Cyanosis and breathlessness may be entirely due to some other condition,,as baart disease or asthma. It is clear that the most expert advice is necessary to a true determination, which must usually depend upon a careful study of excellent x-rays, a search for " aabestosis bodies " in the sputum, a study of the asbestos and other dust exposures over all the patient's life, and a careful elimination of other possible diseases aa causative factors in the production of symptoms. . TREATMENT This is a very serious disease and is practically incurable. Particles once ingested continue their slow, insidious, tissue destruction through years, even though exposure may long igrfy due to . Dyspnea, symptom in . 59%. Be3 the blood, in 56% of * of phlegm i In 11% of osfc doctors, ?b*ble findt ease with* ! tO iwt<alr 'ays.- Even krposure to sderedbe a fibrous at. Bran* \j `cate ji are very ntarely due K - sssary to a a a careful xxdies " m exposures a of other diction of incurable.* ; us, tissue j long ASBESTOsIS 35 I have terminated. We know of no way to stop the action or i to bring about the elimination of asbestos fibers. While those too ho gc to be carried toward the lymphatic glands 0105 be come loosened in the bronchioles from time to time and elimi nated in the sputum, appearing as " asbestosis bodies," the smaller ones are usually in the lung to stay. Of euurse, die bronchitis may be alleviated by usual treat ment directed toward this disease, but it will continue. The patient's general strength should be maintained by study of his hygiene. Usually, death is not due to the asbestosis, but to some other disease particularly of the lung. Therefore, pneumonia must be guaitled against. The shortness of breath on exertion only be met by avoiding heavy work. In time, the patient probably will become a total permanent disability. 'Death usually occurs within a year after die patient can no longer work. COliPLICATIOKS ft la sometimes alleged that tuberculosis is likely to result from this disease, but Merewether (6) points out that only 9*9% of patients with asbestosis show signs of tuberculosis, sslI concludes from his studies that there is no great suscepti\ bUity m pulmonary tuberculosis among workers in asbestos^ *>'*** though they already had fibrosis, since about the same Aomtint of the disease occurred in the general population. Bronchitis and bronchiectasis are almost inevitable. U*AT10N of exposure The discussion relative to symptoms, treatment, and Ekelihool of total permanent disability is based upon the aasump* turn that definite, disabling asbestosis has occurred. 31 the T*nure is slight, as in a well guarded plant with good exhaust Uatioii, insufficient asbestos will be absorbed to destroy a amount of lung. Again, exposure may not continue over ^ yean to have brought about the inhalation at suffi. ^tit dust Usually, the slow beginning symptoms of bran- ! , i > * ` ; : , ` '. .] ' ! ; ' . ( 3G * Asbestosis chitis or shortness of breath cause the employee to change hi; wock to a less dusty or laborious occupation. * The average exposure before the appearance of the disease 5s 13.3 rears. It is very rarely found with less than 5 years labor with this dust, rapidly increases after this duration, and beyond the tenth year, the likelihood of asbestosis is exceed iagly great. * The danger is proportionate to the dust count. If this is . low enough, elimination practically equals the rate of inha la- ., . tion. Helativeiy little dust occurs in those processes after r ' spinning, because the " particles " have become freed, and the fibers have been trapped into a permanent position. Since asbestosis practically does not occur with spinning, unless there has been previous exposure to more dusty processes, it ` is considered that the dust concentration of the spinning room is safe, Merewether (6) found the 'dust count in this depart sent to be as low as 506 to the cubic centimeter, equal to about 13,500,000 to the cubic foot In the dusty departments, the count ran as high as 170,748,000 to the cubic foot INVESTIGATION Investigation must be thoroughly conducted along three lines; duration and intensity of exposure, and the true cause of the disability. Even though the patient may have asbestosis, and has worked for some time with considerable exposure, this is not a sufficient grounds to charge the disability to the present car- f>|4 '' tier alone. The average period of exposure is 13.5 years. Very few men have continued to work this long for a single assured, and but rarely is the same carrier on the risk through* out the entire exposure the patient has had. Obviously the disease was caused by all of the asbestos inhaled, not the fibers respired during the past few months or years alone. Therefore, the disability should be charged pro-rata to all -carriers during the entire time of asbestos exposure. * In fact, to be scientifically accurate, probably little or none of the asbestos inhaled within many months has had time to Hs***. i -- V o d je his f the disease ihon 5 years uration, and is is exceed- , 17 this is :e of mhalaxcesses after, eed, and the tioa. Since amg, uhlea processes, it inning roam this depart* sr, equal to spartments, oot. dong three tnie -%use >, and has this is not resent ear* 13J5 years, or a single k through* dously the i, not the tan alone, ata to all e. * . le or none ad time to Asbestqszs 37 *o through the chemical processes necessary to destroy tissue,' and thus is not a causative factor. This fact probably would not convince a jury that the disease should be charged only to carriers in past years, but it is true that all of the exposure f the patient has had throughout his life contributed pro-rata', {0 the disability in direct proportion to time and concentra tion of asbestos dust The intensity of exposure is important even in the proven case of this disease. Unless the dust count exceeds that usually present in the spinning room, of about 13,500,000 to the cubic fnot. the condition is probably due to previous exposure alone. The protective mechanism of the body is able to handle this amount indefinitely. The true cause of disability must be determined. This necessitates expert study of x-rays, search of the sputum for " asbestosis bodies ", and definite conclusion that other disease i5.not the cause. Unless the experts have had experience with this disease, the Attorney should ask ^hem to read this chap ter, since their text-books will be of little avail, and to par ticularly study the articles of Uerewether listed as (5) and (6.) in the Bibliography. It is not surprising that doctors have had but little experience when it is recalled .that only two cases were reported up to 1928. } *' J: CONCLUSION .. > ____ - l-v~- IN CONCLUSION, THE FOLLOWING POINTS MUST Bt f' . SPECIFICALLY INVESTIGATED: L What intensity of exposure is present with actual j q j ' '** ! asbestos dust coasts well above 13,500,000 per entte ' foot? . - .J JC 2. How long has expoenro continued under the policy sad f ` in what degree of intensity? 3. How long and intensive was exposure throughout the e. IH * ~ * patienfrlife? r "s * `v 4. Are you sure that a diagnosis has not been made,*largely on x-ray findings, without making certain that some other disease as a bronchitis or silicosis may not bo tbe ml causative factor? . ., ? - y- r * 1 ** ,'jv- -14 i J , -1? 3S Asbestosis Obviously these studies necessitate the highest class tech* oica'. experts for determination. Since each case is a probable fatality, any reasonable expense is warranted Only in this way can the Attorney avoid a determination based on history of exposure or sheer guess work, and without properly charg ing disability to all carriers entering into the exposure. Jus tice must be done to both the patient and the Company. -. EISXXOGKAFHY I The fallowin? authorities may be of value taring study and trial: (3) Encyclopedia Briannica. (5) Uereu'ether. E. R. A. The Occurrence of Pulmonary Fibrosis and Other Pulmonary Atfection* in Asbestos Workers. Jour. Industrial Kyr-.f.e. Hay, 1950, p. 198. (6) Ccntmuation of (5) in Jour. Industrial Hygiene, June, 1930, p. 239. (/) Lyr.cu. E. 1L, and Smith, W. A. Asbestos Bodies in Sputum and Luc?. Jour. Am. hied. Assoc. Aug. 30. 'JO. p. 659. (3) Cr-ie. W. . Asbestos Dust and the Curious Bodies Found in Fcimrnary Asbestosis. British Ued. Jour., Sept 28. 79, p. 578. <9J If cl : said. Stuari. Histolooy of Pulmonary Asbestosis. British 3lit Jeur,, Dec. 3. 77. p. 1025. (10) Wi \V. B_ and Gloyne, S. R. Pulmonary Asbestosis. Lancet liar. I, *30, p. 445. , t'A 2*^ K'