Document K6x6LxZzmXwV6p0x3Nod23jJN

FILE NAME Talc TALC DATE 1951 Feb DOC TALC100 DOCUMENT DESCRIPTION NY Dept of Labor Monthly Review Dust Inhalation in Relation to Pulmonary Disease York State Department ofLabor |Copyright U.S. by protected be Division of IndustrialHygiene Safety Vol 30 & February 1951 Standards may and No. 2 party DUST INHALATION IN RELATION TO PULMONARY DISEASE third a JOHN E. SILSON M.D. by Medical Unit Medicne Everyone is inhaling some dust with almost that disease and some other pulmonary pathology every breath taken but the results of this dust of industrial etiology When the ray pic- of upon the lungs is considered part of the natural ture is characteristic as in an obvious case of nod- process of aging when it occurs outside of his oc- silicosis Library cupation The relationship of dust inhalation to pulmonary disease is therefore usually considered only from the point of view of industrial exposure National Observations on the effect of dusts in industry ular the physician is apt to inquire very carefully into the worker's occupation and to en- list the aid of industrial hygienists or other ex- perts in an effort to establish a dust etiology When colection have consequently been limited largely to those the clinical and sometimes even the pathological the pathological processes which can be clearly dif- findings are almost identical with some non of ferentiated from pulmonary diseases of non cupational origin To these characteristic changes cupational disease of the lungs however he is in the lungs produced by dust the term pneumo- not so likely to seek far afield for an occupational coniosis has been applied exposure It was not until the unusual incidence of workers dying from what was presumed to be the from DIAGNOSTIC FACTORS IN PNEUMOCONIOSIS Boeck's sarcoid in a plant manufacturing fluorescent lamps was noted that the toxicity of one In order to establish the diagnosis of pneumo- of the materials which they were handling was copied coniosis two factors must be present 1. pulmon- ary pathology which might have been produced even suspected and that the identity of chronic pulmonary granulomatosis due to beryllium was was by exposure to a particular dust and 2. an occu- established Recognition of the dust etiology is pational history of exposure to that dust The even more difficult when the pathology is identical page chest physician is generally in a good position to with that of a occupational disease as for in- evaluate the first factor through the medium of stance the primary lung carcinoma seen with signs symptoms rays and laboratory tests In increased frequency in chromate workers.2 this determining the second factor he is often handi- on _ capped by his paucity of knowledge of the nature Another way in which dust inhalation may affect of his patient's work and the materials handled pulmonary disease is by aggravation of a pre or co- material Most physicians are aware that a rock miner or existing occupational disease Today the fact stone cutter may be exposed to free silica in am- that silicosis predisposes a worker to tuberculosis The ounts capable of causing silicosis They may not and renders that tuberculosis much more severe be aware however that a worker in a soap factory is well established We are just becoming aware which includes in its products scouring powders however that some of the more innocuous dusts may be handling large amounts of silex which is may adversely affect the course of tuberculosis almost pure pulverized silica In other instances and other pulmonary infections. It is no longer the etiology of the pulmonary pathology may not considered good practice for an individual with be so readily recognized because the physician is arrested tuberculosis to return to work in any unaware of the more obscure effects upon the dusty environment We all too frequently how- lungs of a material such as talc or bagasse ever see workers with chronic bronchitis pulmon- ary emphysema or even bronchiectasis who are Another factor which makes it difficult to recog- permitted to work in an extremely dusty atmos- nize the importance of an industrial dust exposure phere Even the increased coughing induced by in the pathogenesis of a pulmonary disease is the a dust which is slightly irritant the upper res- close resemblance which frequently exists between adessory clear Presented at the Annual Meeting of the New York State Chapter Amer- accumulated particles ican College of Chest Physicians February 16th 1950 York City piratory passages or sages of the cient to aggravate these pas- particles may be suffi i pantonary disease 5 MAR 29 1951 ir cl ie 2 LIBRAY a ears erassameameamaen MONTHLY REVIEW of the DIVISION OF INDUSTRIAL HYGIENE AND SAFETY STANDARDS NEW YORK STATE DEPARTMENT OF LABOR ' 80 CENTRE STREET NEW YORK 13 N. Y. Industrial Commissioner EDWARD CORSI 1st Deputy Industrial Commissioner THOMAS F. MOORE JR Deputy Industrial Commissioner in Charge EDWARD A. NYEGAARD The Division LEONARD GREENBURG M.D. Director MAY R. MAYERS M.D. Medical Unit WILLIAM J. BURKE Chemical Unit GEORGE P. KEOGH Code Unit ARTHUR C. STERN Engineering Unit LEONARD A. PERRIN EngineeIrndiunsgtrUinailt Hygiene LEONARD Building Plans I Over and above all of these specific aspects is the general effect of dust on the aging processes of the lungs would like to quote an observation made by Dr. Edgar Mayer in an article he pub- lished a few years ago " .... Respiratory infec- tions and . general dust exposure eventually provoke pulmonary changes There exist only dif- ferences in degree not in kind between the so- called normal amount of pulmonary fibrosis so prevalent in the general population and those severe fibrotic processes which destroy the lungs of workers in industries wherein exposures exist to more concentrated and continuous effect of the same agents present in greater dilution in the at- mosphere of industrial centers CHARAC DUST CHARACTERISTICS A requisite to the understanding of the ef- fects of dust inhalation upon the lungs is a know- ledge of the type of material under discussion We have chosen to cover in this paper all forms of solid particulate matter generated in the course of industrial operations because in so many instances their effects are similar or even identical Fibers and fumes as well as dusts have therefore been in- cluded Since some uncertainty exists as to the exact meaning of these terms in industrial hygiene we shall start with a few definitions The term dust is applied to the solid particles produced by handling cutting crushing grinding or pounding organic or inorganic materials such as rock ore metal coal wood grain etc. Fibers are the ticles similarly produced from par- ic material organic or inorgan- composed of thread or slender el- ements such as cotton wool fur bagasse or as- bestos and are also created in such operations as stripping spinning and weaving Fume is a term limited to the solid particles created by condensa- tion from a gaseous state generally after volatili- zation from molten metals and often accompanied law Copyright con- trary to general usage it does not refer to densations to a liquid droplet form which are called mists or to a uniform gaseous dispersion] whether visible or invisible which is referred to U.S as a vapor or gas The common denominator of all these materials by is thus the fact that they are present in the atmosphere as solid particles An important protected characteristic of these particles is their size It has been shown both theoretically and experiment- be ally that on inhalation those which are too large may do not reach the lung but are filtered out in the upper respiratory passages Particles which are and too small on the other hand do not settle out and are therefore theoretically not retained in the party alveoli but are exhaled The question of the in- nocuousness of these microscopic particles has third recently been open to question It is a generally a accepted principle however that the particles ex- by ert their greatest deleterious effect upon the lungs when they are between 0.5 and 3 microns in di- ameter Medicne The other important factor determining the re- | action of a dust upon the lungs is its composition of that is its chemical and physical characteristics Library Where it is a mixture of several different com- pounds such as the dust created in a granite quarry the percentage of the most active ingred- National ient in this instance free silica is of the utmost importance Even where the mixture is made and not a natural product its composition has to the be taken into consideration For example the sand of used in an iron foundry may consist of almost pure silica but the dust released in a shake opera- colection tion will have a much lower silical content because a large part of it comes from the iron oxide ticles separated from the surface of the par- the from The particle structure also appears to play caasrtoilneg crystalline silica has long been considered a far | copied frequently more active substance than the amorphous form copied Fumes from a melting operation are much more reactive than the same material creat- was ed as a dust by grinding or crushing In some in- page stances even the shape of the particles has signif- icance particularly when their effects are depen- dent to a large extent upon local mechanical ir- this ritation on PROTECTIVE MECHANISMS materialThe There are a number of mechanisms by which the lung perenchyma is protected from inhaled dust 7 Many of the particles may be filtered out by the coarse hairs guarding the entrance to the nose or trapped by the moist walls of the turbinates Particles deposited on the surface of the mu- cous membranes of the trachea and bronchi are carried like back towards the pharynx by the wave- vibrations of the cilia and also by the cough reflex induced by the irritation to the lining mem- branes Particles which succeed in passing these barriers and gain entrance into the alveoli are ingested by macrophages and which arise from the alveolar walls are commonly referred to as dust cells Some of these phagocytes laden with dust may pass up into the bronchioles and eventually be car- Pulmonary ried off in the sputum the others pass through allergy is a type of response observ- the walls and into the regional lymphatics Some ed with certain organic dusts 12 particularly those Copyright the latter are arrested locally in the peribronch- of plant or animal origin The picture is one of a of iolar tissue but the remainder pass onward into typical asthma and only the occupational history the peribronchial and perivascular lymphatics and differentiates it from identical reactions so comThe dis- U.S. are finally trapped in the lymph nodes at the root tmionncltiyonseoefntefnrcoamn poolnlleynsbeormahdouesebydupsattsch testing by of the lung or similar procedures which will demonstrate ie that the responsible antigen is present in the man's protected TYPES OF PATHOLOGY occupational rather than occupational environ- The type of pulmonary pathology which may be ment be may caused by the inhalation of a specific dust is de- Primary carcinoma of the lung has at one time termined by the manner in which this lung cleans- another been ascribed to a great many of the and ing mechanism is disturbed and by the type of or industrial dusts produced in industry Proving or party reaction which results Probably the best known disproving the carcinogenic properties of any par- is the fibrotic reaction produced by exposure to ticular material is often an extremely difficult third silica This reaction represents a specific cellular procedure because the pathology in no way differs sald response to the material The particles engulfed from that of a lung cancer of unknown etiology a by the dust cells stimulate the production of Merely demonstrating the existence of cancer by fibroblasts in any area where they are congregated and some other pulmonary disease such as silico- and these fibroblasts are eventually replaced by sis is not sufficient since there is no reason why dense fibrous tissue In the case of dusts other the incidence of malignancy in silicotics should be Medicne generalized than silica this fibrosis is usually fairly lower than it is in silicotics The only sat- but with silica it tends to nodular formations along any of such carcinogenicity is the un- of the lymphatics In either case the net effect is to isfactory proof demonstration of an incidence of cancer Library make the lungs less elastic increase their bulk einquwivoorckaelrs exposed to a particular dust which is while decreasing their capacity and decrease blood sufficiently higher than that of a comparable group pulmonary circulation and aeration of the characteristic is the action of those dusts of exposed workers to have statistical signifiGreat care must be taken in selecting the Less National which act as general irritants particularly on the cance to insure that all extraneous factors respiratory passages but do not exhibit a specific control group distribution sex and industrial the fibrosing action Included in this category are most such as age identical The high incidence of of first exposed to environment are the uranium mines of Schneeberg of the organic dusts Workers them respond by sneezing and coughing but usu- lung cancer in has been known for some time.13 colection ally quickly become acclimatized so that the ir- and Joachimatal increased incidence of pulmon- ritant action is no longer found troublesome Con- More recently an has been demonstrated in workers tinued inhalation of these dusts however may re- ary malignancy chromate dusts although the statis- the sult in chronic inflammatory changes in the mu- exposed to of the data which have been col- from tical significance cous membranes lected on this material is still being investigated In addition to this generalized irritant action Asbestos has on occasion been indicated as predis- copied certain dusts may elicit a specific inflammatory posing to lung cancer response This may be of a chemical nature as in was the case of beryllium or Thomas slag or may be PULMONARY DISEASE DUE TO SILICA infectious due to bacteria or fungi carried in by page the dust In both instances the pathology of the depends upon the material producing it Having presented the general types of pulmon- which may be produced by dusts I this raensdpomnasey be acute or chronic reversible or per- ary patlhiokleotgoy devote the remaining time to a brief on manently damaging With some materials for inthe pathology is quite character- would description of the specific pulmonary effects procertain materials As has been previously stance beryllium istic duced by the most important of material . The Even when the dust particles exert no irritant action whatsoever there may be slight pulmonary changes due to their mechanical effects.11 After all insoluble particles which are phagocytized and passed into the lymphatics may be permanently retained in the lungs It is not reasonable to expect that the lungs can become a physiological trap for inordinate amounts of dust and yet retain all their elasticity Prolonged exposure to excessive quan- tities of even completely inert dusts therefore may eventually accumulate in such amounts as to impair function impairment would be the result of a mechanical process the physical presence of large amounts of inert foreign material The term benign pneumoconiosis has been given to this type of pathology in order to contrast it with diseases resulting from the inhalation of ir- ptoheisneteids soiulticaunThdiosubitsetdhley oxide of the element sil- icon and is widely distributed both free and com- bined in the earth's crust Crystalline silica occurs pure as quartz and as beach sand and is also scat- tered in varying percentages throughout many forms of rock such as granite marble and sand- stone Dusts containing free silica can be created industrially in a multitude of ways such as drilling in the course of mining and and blasting operations of stone rock quarrying cutting and shaping crushing sand blasting or any other operations in which quartz sand or containing rock is The disease is characterized anatomic- processed fibrotic changes and the devel- aolplmy ebnyt goefnemrialliiazreydnodulation throughout the lung fields and clinically by cough and progressive shortness of breath Chest rays show at first an ritant matter exaggeration of the lung markings and lymph node enlargement which is followed by nodulation and finally by coalescence and conglomeration Tuber- culosis may be imposed at any stage and is where believed by some to be present in all areas coalescence has taken place As a rule there is no fever or weight loss in simple silicosis and these signs may be indicative of a complicating tuberculosis The patient tends to go downhill very rapidly with the development of an active tuber- culosis lesion ema pulmonary infections and secondary cardiovascular changes due to increased pulmonary resistance are the most common sequelae Chest xrays show a ground glass haziness rather than the reticulation and nodulation of silicosis | Another combined silicate which has been shown to be not completely inert is talc a hydrated mag- nesium silicate used extensively in its powdered | form as a dusting agent It may contain variable percentages of free silica and when these are law Copyright Copyright protected high the classical picture of silicosis has been ob- Many observers have been of the opinion that served in workers mining crushing grinding or be - silicosis could be caused only by the crystalline otherwise handling it Even when it contains under mayand a form of silica but evidence is accumulating to the % free silica however as is usually the case capable v effect that the amorphous form as well is the dust when inhaled is capable of producing a of producing pulmonary damage Observations fine diffuse pulmonary fibrosis similar to asbes- party upon the effects of amorphous silica,,5 have been tosis It tends to be disabling and is frequently made largely on workers exposed to diatomaceous accompanied by dyspnea cough and fatigue In third earth which is a light fluffy material formed by addition deposits of ray opaque material on the the accumulation of skeletons or shells of diatoms pleural surfaces in the form of plaques have been a It has a wide use in industry as filters fillers and observed by absorbents In contrast to crystalline silica it pro- Still another silicate showing definite effects duces fibrosis of the lungs without discrete nodu- upon the lungs is mica which is a double silicate ........./...' Medicne lation The fibrosis is much more marked when the of aluminum and either potassium or magnesium ... ... .../ ...' exposure is to calcined material during which pro- This mineral because it splits into thin sheets of cess microcrystals of chrystobalite may be formed which are quite transparent and have a high di- | Library Another possible example of pulmonary damage electric constant has innumerable uses in industry due to crystalline form of silica occurs in work- | particularly in the manufacture of electrical equip- ers fusing bauxite in electric furnaces in the man- ment For some time it had been believed that the ufacture of alumina abrasives.16 The fumes given chest pathology so prevalent where it is mined was National off in this operation consist,,7 of 25 to 40 sil- due to the free silica present in the rocks in which icon dioxide and 40 to 60 aluminum oxide mica deposits occur Even among workers exposed the together with small amounts of iron oxide and solely to pure mica dust in grinding operations of numerous other impurities Under the electron mi- however there has been observed a high inci- croscope they are revealed as fused particles vary- dence of increased pulmonary fibrosis with cough colection ing in size from 1/100 to micron in diameter rays show a fine granulation of uneven A high percentage of the workers exposed to these density with coalescence of the lesions in more fumes have developed cough with expectoration advanced cases the weight loss anorexia tightness in the chest and In all these exposures the common denominator from dyspnea on exertion ray examinations show a has been silica whether free or combined Recent- lace or granular increase in the lung markings ly however carborundum which is an almost pure copied beginning at the apices These gradually extend silicon carbide containing less than % free silica to involve the entire lung fields and may be ac- has been suspected of being an agent capable of was pulmonary was companied by pleural adhesions causing distor- causing changes indicating more fibrosis usual tion of the thoracic contents Spontaneous pneu- than page mothorax is a common complication While the al- uminum oxide has generally been advanced as the PULMONARY DISEASES OF SILICOTIC ORIGIN etiological agent responsible for this disease it this seems quite possible that this may be a response The pulmonary changes seen in coal miners has on to silica fume with a particle size far lower than . long been attributed to the free silica content of that generally considered injurious the shale through which they had to dig to get at material material Silica when present only in combined form the coal Recent large scale studies in Wales have The The a silicate has usually been regarded as as indicated however that exposure to very heavy inert Considerable evidence however hrealsatbiveeelny concentrations of coal dust with a negligible percentage of free silica such as occurs among the accumulating against this concept Probably the best known of the silicates coal trimmers on the docks leads to a form of producing severe pulmonary damage is asbestos This is pneumoconiosis differing from the anthraco icate occurring in the form of a mineral sil- icosis of miners There is a massive fibrosis of the long fibers which renders it capable of being carded and lungs with nodular deposits of anthracotic pig- spun wov- en into threads and cloth or bonded with cement into building shapes Inhalation of these ment scattered throughout The principal symptoms are due to the marked secondary emphysema fibers in the course of mining or processing asbestos has and the cardiac changes produced by pulmonary hypertension Susceptibility to tuberculosis is in- bofeean shown to be responsible for the development creased The ray picture is one of progresive pulmonary fibrosis with diffuse thickening of the alveolar walls The reticulation rather than nodulation because of the lack of outstanding opacity of the nodules symptoms are dyspnea and a dry cough Emphys- Continued in the March 1951 Issue Castleman Asbestos File on TALC ROM = w= with cover letter or _ memo If DATE = 0 undated CD Document # TALC 01 DATE 1957 Nystate doftfrom medical Review trade journal Monthly Nystate 1 presentation from conference published government report ___ Fed Register notice government inspection results unpublished or internal report unpublished presentation from conference newspaper article letter memorandum - industry warning labels industry sales literature industry recommended practices agenda minutes attendee _..._ s list legal deposition __ testimony of medical records autopsy records