Document gD953Zv2q09xMj6LY76MBKX8Q

m jment of ie Pneusuitable .v asked is j" perience -w made in o, others ?* ewether -~f icient to - v> enough." \sr! nittee on dv >pendices -ir Dust on . v ationery ~p ? at.; KSRte THIS DOCUMENT WAS NOT A RECORD OF PPG INDUSTRIES, INC. DID NOT COME FROM . IT'S FILES AND CANNOT BE AUTHENTICATED Y PPG INDUSTRIES,. INC. " < THE OCCURRENCE OF ASBESTOSIS AMONG INSULATION WORKERS IN THE UNITED STATES* I. J. Selikoff, J. Churg, E. C. Hammond Section on Environmental Health, The Mount Sinai Hospital, Xeic York, N.Y. 'i,*. jItS$?i Information currently available concerning asbestosis has been derived largely from studies of employees of asbestos textile factories and should properly be referred to such individuals. It is inadequate to speak now of `'asbestos workers." With The growth of asbestos utilization, including rapid multiplication of the number and variety of its applications, it would per haps be more accurate to categorize workmen exposed to asbestos as "as bestos textile workers," "asbestos insulation workers," "asbestos miners," "asbestos mill workers," "asbestos-cement workers," etc. The different oc cupations vary widely in important respects; in intimacy, intensity and duration of exposure, in variety and grade of asbestos used, in working conditions, in concomitant exposure to other dusts or inhalants. The im portance of this distinction and the parallel obligation to evaluate and study the experience of asbestos exposure in other trades, is emphasized by the fact that asbestos textile workers are now a minority of those ex posed during the industrial use of asbestos. There were good reasons for the early emphasis on asbestos textile workers. The first cases of asbestosis were in textile workers,1-1 Following the republication of Cooke's case in 1927/ with its rapid confirmation by the report of another case by Seiler/ the Factory Department in Great Britain had to decide whether these were exceptional occurrences or repre sented a significant health risk in industry. Accordingly, an investigation into the problem was undertaken during 1928 and 1929." The scope of the study had to be restricted. The textile industry was selected for study since only here was there pure or almost pure asbestos exposure. Since it was urgent to investigate the effect of this dust, limiting the investigation to this branch of the industry avoided the possible complications which might Jbe introduced by the presence of other potentially fibrogenic dusts. Moreover, in other asbestos trades, there were varying portions of asbestos in the dust to which workers were exposed, which would have added an other complicating factor. It was accepted that there were considerable numbers of workers exposed to mixed dusts whose risk would not bpe docfu?1 I ' > nr.r, H'53?i Subsequent surveys, similarly designed to study the risk of industrial ' SSig ' m ii! asbestos exposure, were also largely confined to asbestos textile works1'" 7"iB'0005460_|^g This study was supported by the Health Research Council of the City of New Vork. sir m; a n* ^ V ' J \jf W 1 i diii COME FROM PPG FILES in 140 Annals New York Academy of Sciences although some described experiences in asbestos mi-lls,'1-'" asfbestos-cement works,'* or factories producing a variety of asbestos products.'3 Such studies had the advantage of having available for investigation sufficiently large numbers of individuals to allow for statistical evaluation of the ob servations made. There was the added advantage that in many of the facr tories there were a considerable number of individuals with extended periods of exposure, allowing for analysis of the effect of prolonged exposure. An important area of industrial asbestos exposure has been asbestos insulation work. The first asbestos factory opened in Great Britain in 1871"' with the expansion of the asbestos textile industry beginning 10 years--.? later consequeni upon the availability of high grade spinning asbestos from * Canada.'7 Yet asbestos was used for heat insulation in 1866.'sAsbestos cement was introduced as a boiler covering about 1870 and other asbestos insulation products were introduced in the next three decades. Commercial production of asbestos insulation materials was recorded at least in 1874." Just as in Great Britain, early studies concerning asbestosis in the United States did not mention asbestos insulation workers. Neither Pan coast7" nor Hoffman"' characterized the asbestos trade in which the work men referred to by them were engaged. The first official claim for compensation associated with asbestos in the U. S. was in 1927 and, again, the nature of the work was not stated." Eliman" in 1934 mentioned a case of asbestosis in an insulation worker. Other cases were subsequently reported,'-'*'7" and in the annual report of the Chief Inspector of Factories for the year 1956,:; "lagging," or insula tion work, was recognized as hazardous. Similarly, Hervieux in France drew attention in 1962 to the dangers of such end product use as insulation work.-" The only large scale survey of asbestos insulation workers was undertaken in the U. S. by Fleischer et al. in 1945. They found only three cases of asbestosis and concluded that "asbestos pipe covering of naval vessels is a relatively safe operation."7" Unfortunately, 95 per cent of those examined by them had worked for less than 10 years at the trade and, as we shall see. evaluation of the risk of insulation workers limited to study of men with relatively short durations of exposure may be misleading. Asbestos Insulation in the United States Asbestos, as a mixture of fiber and sodium silicate, was first used as an insulation material in 1S66 and as asbestos cement about 1870. Magnesia with asbestos as a binder soon followed and air-cell covering, made with corrugated asbestos paper, was introduced in lSSS."1 These materials are still in use, with others. The first union of insulation workers in the United States was formed in New York City in 1834 under a charter issued by the Knights of Labor MGTZ. S OOCUMENT 0 NOT COME FROM PPG Fiv cvv: &S3 Selikoff et al.: Asbest< (.predecessor of the American F Association of Boiler and Pipe insulation workers in this count International Association of Hea ers, with the amalgamation of t and other independent locals th union are insulation workers, p doing construction insulation wo in shipyards and powerhouse co: is in the open air but it sometim ters with poor ventilation. The trade; few are specialists at o material. Conditions of work va company. Among the 1,117 me. than nine per cent of those with worked for one employer prime perience less than half had rema of work practices with insulatior States and with knowledgeable ployers indicates that technique same through the country. Simi practices in other countries73 su; work is approximately the same The asbestos exposurejo.whic and intermittent. Some of-the m; five years ago, the magnesia pipe with no asbestos. Later, much v. felt, cork, rock-wool. In the past come into increasing use and th< foamed and expanded plastics f containing products which are v insulation was and remains perh tains approximately 15 per cen varying asbestos content depend! has 15-20 per cent or less of a; air-cell have a higher asbestos quantities. We have studied the insulatioi in the past, in several ways. Fir llcations from the early part of the major asbestos-containing r especially insofar as the amount ceraed. As expected from know 0 J J r rs J 000546? naval <f those and, as j study ing. d as an agnesia de with ials are 'i % # % formed f Labor f * * * Selikoff et al.: Asbestosis Among Insulation Workers (predecessor of the American Federation of Labor), as "The Salamander Association of Eoiler and Pipe Felters.'':*, In 1910, the present union of insulation workers in this country was chartered by the A. F. of L-, as the International Association of Heat and Frost Insulators and Asbestos Work ers, with the amalgamation of the Salamanders' Association of New York and other independent locals through the country.1' The members of this union are insulation workers, primarily employed in the building trades doing construction insulation work but also employed as insulation workers in shipyards and powerhouse construction and repair. Much of their work is in the open air but it sometimes is, as aboard ship, in rather tight quar ters with poor ventilation. The men generally work at all parts of the trade; few are specialists at one part of it or limit themselves to one material. Conditions of work vary from job to job and from company to company. Among the 1,117 men we have examined (see below), fewer than nine per cent of those with 20 years of work experience or more had worked for one employer primarily -- even after four years of work ex perience less than half had remained with their original employer. Review of work practices with insulation workers from various parts of the United States and with knowledgeable officials of the union and insulation em ployers indicates that techniques, materials and practices are rather the same through the country. Similarly, data published concerning the work practices in other countries*3 suggest that asbestos exposure in insulation work is approximately the same the world^over. The asbestos exposure to which insulation workers are subject is limited and intermittent. Some of the materials used contain no asbestos. Seventy- five years ago, the magnesia pipe coverings had shredded rope as a binder, with no asbestos. Later, much work was undertaken with hair-felt, wool- felt, cork, rock-wool. In the past three decades, fibrous glass products have" come into increasing use and these have been supplemented recently with foamed and expanded plastics for certain applications. Of the asbestos- containing products which are widely used by these men, magnesia block insulation was and remains perhaps the most important. This usually con tains approximately 15 per cent asbestos. While asbestos cement has a varying asbestos content depending upon its manufacture, it also generally has 15-20 per cent or less of asbestos. Asbestos paper products such as air-cell have a higher asbestos content but are used in much smaller quantities. pr | n n We have studied the insulation materials with which theseimfen workid. 1 in the past, in several ways. First, review of old trade and technical pub lications from the early part of the century to about 193017 indicates that the major asbestos-containing materials have remained about the same, especially insofar as the amount and nature of the asbestos content is con cerned. As expected from knowledge of sources of U. S. imports of as- / NG7L:" - ''1 '\3" 1 i.1 rT1r 31 ID NOT COiVic i-fiOM PPG FILES 142 Annals New York Academy of Sciences bestos, chrysotile asbestos was largely used.15 This has been confirmed by analyses of magnesia block obtained during repair work. In later speci mens so obtained, crocidolite has also been found. Moreover, materials used for ship insulation, while containing the same amounts of asbestos as above, began in 1934 to have significant amounts of amosite in addition to chryso tile, because of the lighter weight of the material.*' Marr" has recently brought shipyard insulation experience up to date, comparing it with the observations of Fleischer and colleagues,*' and concludes that ". . . insula tion materials and work methods have remained essentially the same" since 1945. Measurement of dust exposures of insulation workers have been but in-,-; frequently reported and have been hampered by the varied nature of the1' work. As in other asbestos work, peak counts are met which are exces sively high but generally counts for asbestos fibers have been within the five mppcf. M.P.C. of the A.C.G.I.H.TM*1" Such counts as have been available, made during work engaged in by the men studied by us, have shown a range similar to that of published counts.14 Present Investigation We undertook to study the question whether asbestos exposure during insulation work in the U. S. was associated with the hazard of asbestosis and its complications. Our investigations have been concerned with the 1522 members of the insulation workers union in the New York (Local 12)New Jersey (Local 32; metropolitan area,. The New York Local of the Union is a direct lineal descendant of the Salamanders' Association, and is the oldest Union of insulation workers in the U. S. The 1522 men studied by us include all members of these Locals from 1942 to 1962. On December 31, 1942, there were 632 members and 830 men subsequently joined be tween 1942 and December 31, 1962. This includes every man who was a member of either of these locals at any time in this period, whether or not he remained in the trade as an insulation worker,/ It is believed that the experience of these men fairly represents a cross section of the experience of insulation workers during the history of this trade in the U.'S. Records of the union indicate that these locals had 335 members in 1914 and that 1738 members were admitted to these locals from 1915 to 1963. In the United States as a whole, the Insulation Workers Union in 1914 had 1487 members and 23,333 were admitted from 1915 to 1963. The adequacy of our sample can be gauged by reference to these figures (see table 1).- However, our data does not include information concerning nonunion in sulation workers, maintenance insulation workers, insulation work as part of other trades or undertaken by insulation' workers in other unions. The number of men involved in insulation work in these areas is not known to us. 1 ., -------------- -.............. - * i ' v;-i Selikoff ct al.: Asbes Study of Asbestos Insvi Adi Total U. S. Membersh. Total NYrNJ Member: Examined NY-NJ Men Following insu: 1. Nonunior 2. Some nu 3. "Sprayet 4. Insulatic 5. Insulatic From January 1, 1943 to D of this study on January 1, locate and examine every m; ment status. For this purpos The cooperation of the union records were made available . one. Its members are well-; among these workmen. Accc weekly, are maintained by tht to obtain the entire work his plement the work histories o tions (see below), and was i to establish onset of employm men not examined. From the available concerning every de the period covered by our stt cates were obtained, facilita protocols, histological materi: Of the 1258 men alive at t ing members of the union, ( 34 were not working becaus union and were no longer er wise employed (table 2). One thousand one hundre (89.9 per cent) presented t: of the 1086 of the working. rn i "'rn i$ during estosis ith the al 12)of. W .t:uacdied :ember ted bewas a or not iat the rrience ecords d that In the i 1487 acy of L 1); `On in is part s. The known -a :? - a*. *5 From January 1, 1943 to December 31, 1962, 264 men died. At the stasi of this study on January 1, 1963, 1258 men were alive. We attempted to locate and examine every man alive on that date, whatever his employ ment status. For this purpose, invitation for examination was voluntary. The cooperation of the union and its membership was freely given. Union records were made available and were very valuable. The union is a stable one. Its members are welhpaid, skilled craftsmen, with little ^turnover among these workmen. Accurate, detailed employment records, collected weekly, are maintained by the union and from these records it was possible to obtain the entire work history of each man. This data was used to sup plement the work histories obtained from the men during their examina tions (see below), and was utilized to provide employment data*sufficient to establish-onset of employment and duration of work experience for those men not examined. From the health and welfare records, information was available concerning every death among the members of these locals^ring the period covered by our study and, utilizing these records, death certifi-' cates were obtained, facilitating the location of hospital records, autopsy protocols, histological material, etc. Of the 1258 men alive at the start of this study, 1086 were active work ing members of the union, 63 were retired (principally because of age), 34 were not working because'of illness and 75 had withdrawn from the union and were no longer engaged as insulation workers, but were other wise employed (TABLE 2). One thousand one hundred and seventeen of the 1258 living members (.89.9 per cent) presented themselves for examination. This included 984 of the 1036 of the working, members, 50 of the 63 retired members, 28 of 144 Annals New York Academy of Sciences In ililiW --! _VJK js: Selikoff et al.: Asbe iu-lf Table 2 Asbestos Workers Union Survey 1963-1964 Q CO ;v,T UJ Examination of -1 !i II Iii- Years from onset Deceased Retired 50+ 40-49 30-39 20-29 10-19 0-9 25 ^ 79 107 39 9 5 264 22 35 6 0 0 0 63 m Withdrawn Working members 8 17 5 2 2 0 34 1 10 22 7 24 11 75 5 43 185 75 385 393 1086 Total alive 36 105 218 84 411 404 1258 ;r Onset of exposure V- ,, Prior to examination (yrs. , 1 -tgj A,* 3 e- -- 50+ *"lS '-'K 45-49 ^- { -o 40-44 35-39 30-34 ", Vr-* -Am* r *} 25-29 20-24. 15-19 1,522 members January 1, 1943-December 31, 1962 a< * I ii ; the 34 who were ill and 55 of the 75 members who had withdrawn from ^ u] O 10-14 5-9 0-4 insulation work {table 3). Table 4 contains an analysis of the 1258 men "TTM" oo according to lapsed time from onset of their employment. It will be seen --Z- , i that the very large majority of men in each lapsed time category was ^ examined. This inclusiveness of the survey was very gratifying for two Analysis by group, according reasons. First, it will be seen from an analysis of TABLE 2 that a high pro- portion of the older members, with long work experience and with longer periods of lapsed time from onset of employment are included among the "retired," "ill," or "withdrawn" classifications. To have omitted these men would have led tq inaccurate, selected data. It would certainly have made i - - i Table 3 Asbestos Workers Union N.Y.-NJ. 1943-1962 ? p- . y IV " ^ difficult the establishment of t of exposure or the effect of a 1 Second, in addition to data c< was obtained detailing the ac period from onset of employrr more or less coincided; iir son significantly less than the elap parison of such data is of inte Status January 1, 1963 (1,522 members) 1. Deceased...................................... 264 2. Alive............................................. 1,258 of actual work exposure from t initial exposure with inhalatio i* Examination of each man im i were recorded concerning onset rl cause, number of employers, u died and employment in particu Status ----- No. Examined % Examined as shipyard work and powerhi Retired m Withdrawn Working 63 34 75 1,086 50 79.3 28 82.4 55 76.4 984 90.6 was noted, including previous . rent symptoms such as dyspne: tinal complaints. Smoking habi onset, number of cigarettes sn 1,258 1,117 89.9 individual was no longer worl Physical examination was part 632 Members Dec. 31, 1942. 890 admitted Jan. 1, 1943 to Dec. 31, 1962. .? Status of men examined during survey 1963-1964. * examination of the skin, nose Chest expansion was measured Total alive ' '4? 1258 hdrawn from che 12-5S men : will be seen category was ying for -two. .t a h proi T^^fc.onger sd Ifflong the ed these men !v have made Examined 89.9 >c. 31, 1962. Selikoff et al.: Asbestosis Among Insulation Workers 145 Table 4 Examination or Asbestos Insulation Workers Onset of exposure Prior to examination (yrs.) No. Examined 50+ 45-49 40-44 35-39 30-34 25-29 20-24 15-19 10-14 5-9 0-4 36 41 64 92 126 18 66 186 225 184 220 1,258 28 39 54 83 111 16 61 174 (91.6%) 205 154 192 (87.6%) 1,117 r.'t n: I!' ?! \m 1 H! Analysis by group, according to onset of work exposure, difficult the establishment of the effect o*f a long lapsed period from onsejt of exposure or the effect of a long duration of exposure. Second, in addition to data concerning onset of employment, information was obtained detailing the actual number of years worked during the period from onset of employment. While in many cases the two periods more or less coincided, in some cases the number of years worked was significantly less than the elapsed time from onset of exposure. The com- parison of such data is of interest when attempting to separate the effect of actual work exposure from the effect of mere passage of time from the initial exposure with inhalation and retention of asbestos fibers. Examination of each man included a detailed occupational history. Data were recorded concerning onset of employment, interruptions for whatevec cause, number of employers, use of protective respirators, materials han^ died and employment in particularly suspect areas of insulation work suchl>' as shipyard work and powerhouse construction work. Health experience was noted, including previous illnesses and hospitalizations, as were cur rent symptoms such as dyspnea, cough, sputum, hemoptysis, gastrointes tinal complaints. Smoking habits were recorded in detail including age at onset, number of cigarettes smoked, and pipe and cigar smoking. If the individual was no longer working, the reason for this was ascertained. Physical examination was particularly directed to the chest, but included examination of the skin, nose 3nd throat, finger clubbing and cyanosis. Chest expansion was measured, hemoglobin and urine were routinely ex- z rj ill O c; 'J 1_SB_000566~7 tvZi 146 Annals New York Academy of Sciences amined. Vital capacity was measured in all cases and in many, additional measurements such as M.E.F.R. TVC and MBC were also made. In many cases, sputum was examined for' asbestos bodies and in almost half, blood . was drawn for special serological studies. In selected cases, extended pul monary function investigations were undertaken, including arterial gas studies, lung compliance, pulmonary airway resistance, measurement of ventilatory parameters and diffusion studies. X-ray studies were perhaps the most important part of the examination. In each case, a standard posteroanterior film was taken but, in addition,.^ another posteroanterior film utilizing a slightly more penetrating kilovolt-- age technique was also exposed. Our experience indicates that this maneu- " ver is valuable in X-ray examinations in this disease. The standard tech nique is required siftce over-penetration may well result in the loss of fine reticular fibrosis and, indeed, in individuals with relatively brief work histories, it is sometimes advantageous to take a third posteroanterior film with a slightly under-penetrating technique if such minimal fibrosis is suspected. However, in the men with longer work experience, increased penetration may be required. First, these men do a good deal of manual labor and are often heavily muscled. Second, pleural fibrosis is common and parenchymal fibrosis usually coexists, both decreasing radiopenetra bility. Third, such increased penetration is often required to demonstrate calcification, especially when it~coexists with extensive pleural thickening or is located in such areas as the posterior diaphragmatic sulcus, behind the heart, in the mediastinal pleura, etc. Oblique films in both anterior oblique positions were also routinely taken in each case. While this has obvious applicability in a disease with such lower lobe preponderance as asbestosis, we have found it particularly val uable in the demonstration of pleural calcification. ___ -- Residta Among the asbestos insulation workers examined by us. evidence of pulmonary asbestosis was" present in almost half the men examined. In this evaluation, radiological change has been used as the sole criteria (table 5). We understand, of course, that evaluation of the presence and extent of asbestosis limited only to X-ray findings tends to result in underestima tion cf the incidence of asbestosis, but few instances of disabling disease will be so overlooked. Analysis of our data indicates that radiologically evi dent pulmonary asbestosis varied directly with the duration of exposure. Insulation workers with relatively short periods of exposure have a sig nificantly lower incidence of pulmonary asbestosis and this, when present, was generally of minimal extent. Of 346 men whose exposure had begun less than ten years before exami nation. only 36 or 10.4 per cent showed any radiological abnormality.- In Selikoff et al.: Asbesto X-ray Chances in A 1 Onset of exposure (yrs.) No. % Nort 40+ 30-39 20-29 10-19 0-9 121 194 77 379 346 1,117 5. 12. 27. 55, 89. 51. each of these cases, the reticular none was there evidence of pleu fibrosis seen. Of 379 men whose before examination, more than h mality was seen on X-ray in 16' asbestosis greater than minimal, fibrosis and in five, evidence of cal On the other hand, among the from onset of exposure, the very monary asbestosis. Among the years prior to examination, 56 s examination took place from 30 almost 9 of 10 showed abnorma years from onset of exposure onl over, the asbestosis in these case and severe and pleural calcificat Pulmonary asbestosis has bee: dyspnea the essential complain symptom among the men studies seen in those men with less than an important symptom after tb years from onset of exposure, c 32 others complained of minims other hand, of the 392 men wit posure, 134 had dyspnea of sor greater or lesser extent. There was incomplete correlat (considered as parenchymal fibi were seen with no roentgenogra additional de. In many t half, blood ttended puK arterial gas surement of xamination. in addition, ing kiiovolt-i this maneu- '^er r.dard tech- s .* loss of fine brief work teroanterior r\ maj fibrosis e, increased ''S" 1 of manual is common idiopenetra- ' demonstrate 1 ning Ict^B nind .p 4 fW> fc <? tinely taken e with such 'C. icularly val- * evidence of led. In this ria (TABLE and extent derestima.ing disease igically evi>f exposure. have a sig'.en present. fore examirmalitv. In * $ V r -*r .f * Z .i * r Selikoff et al.: Asbestosis Among Insulation Workers Table 5 X-ray Changes in Asbestos Insulation Workers - Onset of d exposure (yrs.) No. % Normal 40+ 30-39 20-29 10-19 0-9 m 194 77 379 346 1,117 5.8 12.9 27.2 55,9 89.6 51.5 % Abnormal 94.2 87.1 72.8 44.1 10.4 48.5 Asbestosis (grade) 12 35 51 102 49 35 17 158 9 36 0 366 126 3 28 18 4 0 0 50 each of these cases, the reticular infiltration was minimal in extent and in none was there evidence of pleural calcification. In only four was pleural fibrosis seen. Of 379 men whose exposure had begun from 10 to 19 years before examination, more than half still had normal X-rays. Some abnor mality was seen on X-ray in 167 of these cases but in only nine was the asbestosis greater than minimal. In 35 of these men there was some pleural fibrosis and in five, evidence of calcification." On the other hand, among the 392 men with more than 20 years elapsed from onset of exposure, the^verv large majority had X-ray evidence of pul monary asbestosis. Among the 77 whose exposure began from 20 to 29 years prior to examination, 56 showed abnormal films. Among 194 whose examination took place from 30 to 39 years following onset of exposure, almost 9 of 10 showed abnormal films while, of those with more than 40 years from-onset of exposure only one in 20 showed no abnormality. More over, the asbestosis in these cases tended to be considerably more extensive and severe and pleural calcification and fibrosis were commonly seen." Pulmonary asbestosis has been called a monosymptomatic disease, with dyspnea the essential complaint. Analysis of our data concerning this symptom among.the men studied by us indicates that it was uncommonly seen in those men with less than 20 years from onset of exposure but was an important symptom after that. Thus, of 725 men with less than 20 years from onset of exposure, only one had significant dyspnea although 32 others complained of minimal dyspnea on exertion (table 6k On the other hand, of the 392 men with more than 20 years from onset of ex posure, 134 had dyspnea of some degree, 61 of them with disability of greater or lesser extent. There was incomplete correlation between the roentgenographic findings considered as parenchymal fibrosis) and dyspnea on exertion. Two cases were seen with no roentgenographic evidence of parenchymal fibrosis hut -- NOTE: THiS DOClFefT DID UUiViC. f fU.:i'.'i vhcii 5*'v> Pr^'CAt't ' " -- 148 Annals New York Academy of Sciences Table 6` Dyspnea among Asbestos Insulation Workers Onset of exposure (yrs.) No. %` Normal 40+ 30-39 20-29 10-19 0-9 121 194 77 379 346 1,117 52.1 70.6 76.6 92.6 98.6 % Dyspnea 47.9 29.4 23.4 7.4 1.4 Dyspnea (degree) y 12 26 17 35 14 12 3 27 1 50 105 35 3 -: <i 16 8 3 0 o* 27 -rj Selikoff etai.: Asbestosi case did we fail to find typical p asbestos bodies present. However, ' early changes since in only one ca years from onset of exposure. In j Grade I, in 16, Grade II and in 14, the asbestosis suffered by these asl than that occurring in workers exp portunity of examining lung tissu making asbestos insulation materi; by the members of the Asbestos "V limited and conclusions perhaps un\ gests that the pulmonary fibrosis am with complaints of significant dyspnea, but discrepancy of this extent was rare (7A3LE 7), On the other hand, of 99 cases with more than 20 years from onset of exposure, and with evidence of moderate or extensive parenchymal fi brosis, moderate or severe dyspnea was present in little more than one of four. Thus, significant disability may be present with relatively little to be seen on X-ray and, conversely. X-ray changes may be extensive with little functional difficulty. Similar incomplete correlation has been recorded be tween the results of pulmonary function studies and roentgenographic appearances.TM We have been able to obtain lung tissue for examination from 45 asbestos insulation workers, primarily from the 307 men who died from 1942 to- 1964. although in a few cases operative specimens were available. In no Table 7 Correlation of Dyspnea and Roentgenologic Evidence of Pulmonary Fibrosis among 392 Asbestos Insulation Workers with at Least 20 Years from Onset of Exposure Grade of parenchymal fibrosis 0 1 2 3 Per cent No.. . Grade 2-3 dyspnea 53 2% 240 11% 77 21% 22 27% 392 Years from onset of exposure 35+ 20-34 Grade of dyspnea Grade of dyspnea 3-- 0 1 2-3 0 1 2-3 15 0 75 20 27 8 45 121 33 1 31 5 27 86 28 16 14 8 6 33 50 134 44 1 4 4 1 10 i <2 V i : .. i i f U Pulmonary Fibrosis on 1. Asbestos insulation building trad> a. Less 15 years from onset b. Over 15 years fronr onset 2. Asbestos insulation factory work a. Less 15 years from onset b. Over 15 years from onset than among the Building Trades Uc marizes these pathological studies. Mortality experience in this grou It may be remarked here, however, mesothelioma of the pleura and per beyond that expected.1*" In additic stomach and colon was also found t In the roentgenological survey, bt lung cancer among workmen exposet paid to this finding among the men found, and in one, pleural mesotheli was obtained. In six cases, thoracot currently, alii'e following apparently : n;;) ............... pp i a :;rv .-rGriLES -- \ea (degree) JS* 23 17 16 --I-- 14 8 : 3 3; 1 0^ 00 35 27 his extent was "4 from onset of arenchymal fi re than one of tJAL .ely little to be '*1 5sive with little n re'-'ded be;raphic i om 45 asbestos 't from 1942 to vailable. In no 53 3 Pulmonary at Least 5 s exposure 20-34 * ade of dyspnea 'i 1 1 2-3 i i 15 1 6 28 4 i8 4 33 1 > * 44 10 Selikoff ef al.: Asbestosis Among Insulation Workers case did we fail to find typical pulmonary asbestosis, with fibrosis and asbestos bodies present However, our material is inadequate to evaluate early changes since in only one case was there a history of less than 15years from onset of exposure. In 15 cases, the pulmonary fibrosis was Grade I, in 16, Grade II and in 14, Grade III. We have the impression that the asbestosis suffered by these asbestos insulation workers is less severe than that occurring in workers exposed in factories. We have had the op portunity of examining lung tissue from ll men working in a factory making asbestos insulation material (one of the brands actually utilized by the members of the Asbestos Workers Union). Although the data are limited and conclusions perhaps unwarranted, analysis of the findings sug gests that the pulmonary fibrosis among these men was significantly greater Table 8 Pulmonary Fibrosis on Histological Examination Fibrosis (grade) No. 0123 1. Asbestos insulation building trades workers a. Less 15 years from onset.................. 1 b. Over 15 years from onset. ................. 44 "___ - -j 45 0 100 0 14 16 14 0 15 16 A 2. Asbestos insulation factory workers a. Less 15 years from onset. ^............. 5 0 0 2 3 - b. Over 15 years from onset . i............. 6 0 0 2 4 11 0 0 4 7 i'i 0 r. t IP than among the-Building Trades Union Insulation Workers. Table 8 sum marizes these pathological studies. t,1 ii: Mortality-experience in this group of men will be separately reported.11 It may be remarked here, however, that the incidence of lung cancer and mesothelioma of the pleura and peritoneum was found to be considerably beyond that stomach and expected." " In addition, the incidence colon was also found to be elevated. of carcinomTa o*f Ttl .5 n/ Ji In the roentgenological survey, because of the known increased risk of lung cancer among workmen exposed to asbestos, particular attention was paid to this finding among the men examined. In 10 men, lung cancer was | BB 0005470 found, and in one, pleural mesothelioma. In each, histological verification was obtained. In six cases, thoracotomy was undertaken. Three men are currently alive following apparentlv successful reqiQy^l,qf,neoplpms,;Ax N0TE: T":" '" - w !! NOT COiViE FROM PPG FILtS | fir.- x 150 Annals New York Academy of Sciences Selikoff et al.: Asbestos! with significant pulmonary asbestosis, positive findings insofar as lung' ; cancer and pleural mesothelioma were concerned occurred among the 392 : :_ men in the 20 years from first exposure group (table 9). The importance w of including the men with longer work experience in a survey of workers exposed to asbestos is well-illustrated by these findings. Similarly, the im-\i. portance of including all members of an original cohort is also demon---- among these men showed this neop weighted in another direction, sim compensation," Wegelius11 studied tails of employment are not given i contained few men with prolonge studied was in existence for "about: strated. Table 9 provides an analysis of the occurrence of lung cancer^--. according to status of the individuals examined. Of the 1086 working.;*-' In the study by Horai in Japan, more than 20 years of work expen members, 984 were examined and among these, seven were found to taken by Fleischer et at.,yj only 51 o lung cancer (0.7 per cent). There were 172 men no longer actively at workrW1 being retired, ill or having withdrawn from the group to work at other L- 10 years of work experience and ir who were examined. Frost11 et al. st trades. One hundred and thirty-three were examined and four were found > ers in Copenhagen with more than to have lung cancer (three percent). survey was limited to currently r of approximately one-third of an o Table 9 Lung Cancer Found during Examination of 1,117 Asbestos Insulation - *- Workers -5 study by Doll41 is not comparable, by him were "coroners' necropsies, cases since these necropsies-are or Years from onset of exposure 40+ 30-39 20-29 10-19 0-9 Number examined 121 41 17974 379 346 1,117 Working members Number Cancer 45 .. 168 72 362 337 984 1 3 3 0 0 7 Others Number Cancer 76 2 26 . 2 5* 0 17 0 90 133 4* ion, there may be a question of a. death. There were 18 cases of lunj among 75 cases with asbestosis ar tosis. However, this series exclude, in the opinion of the coroner, inc a contributory cause. In the seconc who had worked in one particular f men there were 39 deaths, 11 due t 0.8 was expected. However, these r in heavily exposed areas and may Includes one instance of pleural mesothelioma. group. With reference to comparison w It will be seen from table 9 that we found no cancer of the lung among those men examined whose work had begun less than 20 years before the date of examination. We find it difficult to compare the results of this investigation with previously reported surveys of workers exposed to asbestos. In many in-- stances, the conditions of the studies do not allow for such comparisons. In Merewether's study,* 363 men were analyzed but only 133 were X-rayed. All were at work, except one, on the day of examination. Only 21 or 5.8 .>* per cent had 20 years or more of work experience. The 126 men studied by Lanza* were "selected at random" and were at work at the time of -:- examination. Smith*" has drawn attention to the dangers of drawing con-d elusions from men at Avork, pointing out that examination of 323 Joachims- tal miners failed to reveal any lung cancer, yet 43 of 89 post-mortems ; of asbestos textile workers, it api portant risk among insulation wo ticularly true of those men who h posure. This risk includes lung ca the pulmonary asbestosis. It migt neoplasms were also found during provisional diagnosis of abdomina at laparotomy to be a carcinoma anemia in another led to hospitaliz noma of the stomach was found. O ing for examination included care nasopharynx, carcinoma of the col Scattered case reports have previ insulation workers, including botl rivJ.Vi rV'U V\ 0 -C.S rr n r\ . ` "j 0005471 ofar as lung > nong the 392 .35 e importance y of workers 3larly, the im- 3?.Tf also demon- -| lung cancer 0S6 working^^ ound to have vely at work, ork at other r were found \ ~~ Ixst LATION Xhers 5 :cer 2 0. 00. ri-t - lung among f? rs before the A :igation with In many incomparison3. cere X-rayed, nly 21 or 5.8 men studied : the time of drawing con123 Joachimspost-mortems Vt Selikoff et al.: Asbestosis Among Insulation Workers among these men showed this neoplasm. The cases studied by Stone4' were weighted in another direction, since they were individuals, "applying for compensation." Wegelius'- studied 126 cases of 476 men at work and de tails of employment are not given in this report. It is likely that the group contained few men with prolonged experience since the industry being studied was in existence for "about 20 years.'" In the study by Horai in Japan,'J of the 329 men surveyed, only 10 had more than 20 years of work experience. As mentioned, in the study under taken by Fleischer et al.,*' only 51 of the 1074 men examined had more than 10 years of work experience and in this study, too, it was the men at work who were examined. Frost'-' et al. studied 31 of 34 asbestos insulation work ers in Copenhagen with more than 20 years of asbestos exposure, but this survey was limited to currently active men who represented a residual of approximately one-third of an original cohort of "about 100." Even the study by Doll41 is not comparable. The 105 consecutive autopsies reviewed by him were "coroners' necropsies." These are not necessarily consecutive cases since these necropsies are ordered by the coroner when, in his opin ion, there may be a question of asbestosis being a contributory cause of death. There were 18 cases of lung cancer found in this group of men, 15 among 75 cases with .^bestosis and three among 30 cases without asbes tosis. However, this series excludes those individuals whose death did not, in the opinion of the coroner, include the possibility of asbestosis being a contributory cause. In the second part of this study, Doll traced all men who had worked in one particular factory for at least 20 years. Of 113 such men there were 39 deaths, 11 due to lung cancer, all with asbesto.)3, while 0.8 was expected. tHowever, these men included only those who had worked in heavilfv expose-dt areas and may in this regard be considered as a select group. With reference to comparison with findings in other surveys, primarily of asbestos textile workers, it appears evident that asbestosis is an im portant risk among insulation workers exposed to asbestos. This is par ticularly true of those men who have at least 20 years from onset of ex posure. This risk includes lung cancer and mesothelioma associated with the pulmonary asbestosis. It might be added, parenthetically, that other neoplasms were also found during the survey. Scleral jaundice led to the provisional diagnosis of abdominal neoplasm in one case, later confirmed at laparotomy to be a carcinoma of the pancreas. Marked hypochromic anemia in another led to hospitalization during which an inoperable carci noma of the stomach was found. Other carcinomas present in men appear ing for examination included carcinoma of the tongue, carcinoma of the nasopharynx, carcinoma of the colon, and carcinoma of the bladder. Scattered case reports have previously been recorded of neoplasms among insulation workers, incl^ing.J>qth lyng cancer43"1-' and mesothelioma4' tyn -r'y,:vy}-\ 1aLr p41 X%r. 152 Annals New York Academy of Sciences of both the pleura and peritoneum. A lung cancer has also been reported in a workman in a factory making asbestos insulation." However, these reports, while interesting and valuable, could not establish an association between the two conditions. It is possible that additional lung cancers and mesotheliomas have occurred and may even have been reported but such reports do not state the nature of the asbestos exposure and such instancesmay be included among cancers in "asbestos workers." Our experience that the lapsed period from onset of exposure is gener- ally prolonged before the appearance of lung cancers in asbestos insulation.workers coincides with the general experience of long `latent periods" in i such cases. Indeed, in the infrequent cases in which very short periods^ .have elapsed from onset of exposure, it might well be that the lung cancer found is coincidental. Such long latent periods would correspond to simi larly prolonged periods, associated with lung cancer in chromate workers,** nickel" cancers, arsenical lung cancers5*1 and the increased incidence of:. lung cancer among regular cigarette smokers." In Doll's series,*1 a long latent period was noted in all cases. Neoplasms have also been reported among individuals indirectly exposed . to asbestos insulation work, as carpenters,'"' steam fitters," and other building trade workers." Summary An investigation involving 1522 asbestos insulation workers in the New York-New Jersey metropolitan area has been conducted. Among 392 in dividuals examined more than 20 years from onset of exposure, radiologi cal evidence of asbestosis was found in 339. In half of these, the asbestosis was moderate or extensive. In individuals with less than 20 years of exposure, radiological evidence of asbestosis was less frequent and when present, much less likely to be extensive.' Neoplastic complications of asbestos exposure were studied among 307 consecutive deaths in this group of men. Lung cancer was found to be at least seven times as common as expected and cancer of the gastrointes tinal tract three times as common as expected. There were 10 instances of mesothelioma of the pleura or peritoneum. Of the I25S men alive at the start of this survey, 1117 were examined. Eleven cancers of the lung or pleura were found during this survey of the living members, all among the 392 men with more than 20 years from onset of exposure. No cancers were found in those men, the onset of whose work experience was less than 20 years. We may conclude that asbestosis and its complications are significant hazards among insulation workers in the United States at this time. sis -a - * - i ';. I . i . y.-rzr,-" tr&t Selikoff ef at.: Asbestosi Acknou The executive officers of the Inter Insulators and Asbestos Workers, membership of the New York and . valuable cooperation in the investig trative Assistant, Janet Kaffenburg, many details necessary to the comp Ref 1. Murray, H. M. 1907. In Report of sation for Industrial Disease. M : c.d. 3495, c.d. 3496. Wyman and 2. Auribault, M. 1906. Note sur l'H Filatures et Tissages d'Amiante. 3. Cooke, W. E. 1924. Fibrosis of tl dust. Brit. Med. J. 2:147. 4. Cooke, W. E. 1927. Pulmonary as 5. Seiler, H. E. 1928. A case of pn asbestos dust. Brit. Med. J. 2:981 6. Merewether, E. R. A. & C. V. Pri on the lungs and dust suppressit rence of pulmonary fibrosis an workers. Part II. Processes giv pression. H.M.S.O. London, Engl 7. Wood, W. B. & S. R. Gloyne. 193 hundred cases. Lancet 2:1383-13 8. Lanza, A. J., W, J. McConnell . halation of asbestos dust on the Rep. 50:1-12. 9. McPheeters, S. B. 1936. A sun asbestos dust. J. Indust. Hyg. 18: 10. Dreessen, W. C., J. M. Dallavaj Easo.m St M. F. Trice. 1938. A industry. Public Health Bull. N< 11. Horai, Z. & M. Ueshima. 1961. S 12 (6):1148-1163. 12. Wegelit'S, C. 1947. Changes in the in Finland. Acta Radiolog. 28:13 13. Smith, &. W. 1955. Pulmonary di Indust, Health. 12: 198-203. 14. Clerens, J. 1950. Recberches sur i Belg. Med. Soc. 8: 557-565. 15. Fulton, W. B., A. Dooley, J. L. M Part III. The effects of exposure ing plants on the health of a grc Industry, Bureau of Industrial vania. Harrisburg, Pa. Spec. No. 16. The Asbestos Fact Book. 1953. 3 17. CiRKEL, F. 1905. Asbestos. Its occ Canada. 18. Bowles, O. 1937. Asbestos. U.S. I 403: 9. U,S. Government Printing 19. Product Manual "Asbestos." li Boston, Mass. GC I'G'O 00 05 q 73'y ?s Iso been reported * However, these sh an association.vW-t; lung cancers and ~ epcrted but such nd such instances , xposure is gener-^s^ jbestos insuiatioift^ _ atent periods" in */'*-'* *ry short periods -- it the lung cancer .- frrespond to simi- romate workers.14 v ised incidence of 's series,a long .->/ i" -_ ndirectly exposed ters" and other ----------------------- :4 >rkers in the New !. Among 392 in* posure, radiologithese, the asbes* 53 than 20 years equent and when idied among 307 s found to be at the gastrointesi 10 instances of 7 were examined, his survey of the n 20 years from he onset of whose 2: ** *C v; r? -5. -^T j? is are significant at this time. Selikoff etal.: Asbestosis Among Insulation Workers A cknowledgm en ts The executive officers of the International Association of Heat and Frost Insulators and Asbestos Workers, Washington, D.C., and the officers and membership of the New York and Newark, N-J-, locals of this union gave valuable cooperation in the investigation. We are indebted to our Adminis trative Assistant, Janet Kaffenburgh, for the successful management of the many details necessary to the completion of this study. .-i- r.' Reference* Murray, H. M. 1907. In Report of the Departmental Committee on Compen sation for Industrial Disease. Minutes of Evidence, Appendices and Index. : c.d. 3495, c.d. 3496. Wyman and Sons. London, England. Aurirault, M. 1906. Note sur l'Hygiene et la Securite des ouvriers dans les Filatures et Tissages d'Amiante. Bull, l'lnspect. Trav. : 126. CoOKE, W. E. 1924. Fibrosis of the lungs cue to the inhalation of asbestos dust. Brit. Med. J. 2:147. Cooke, W. E. 1927. Pulmonary asbestosis. 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Mesothelioma of the pieura or peritoneum and limited basal asbestosis. S, Afr. Med. J. 36: 759-760. Dtp ?cc GG I U I BB 0005476 i!