Document 5L90y3moZn7p6VVZ0GbbMGVk0

FILE NAME State of the Art Literature SAL DATE 1979 DOC SAL078 DOCUMENT DESCRIPTION Journal Article - Mortality Experience of Insulation Workers in the US and Canada 1943-1976 MORTALITY EXPERIENCE OF INSULATION WORKERS IN THE UNITED STATES AND CANADA 1943-1976 Irving J. Selikoff Environmental Sciences Laboratory Mount Sinai School of Medicine The City University of New York New York New York 10029 E. Cuyler Hammond and Herbert Seidman Department of Epidemiology and Statistics American Cancer Society New York New York 10017 In 1964 we reported data concerning the mortality experience of a cohort of asbestos insulation workers in the New York Jersey metropolitan area 1943 1962. Significant increases in deaths of lung cancer mesothelioma gastrointestinal cancer and asbestosis were found Findings were limited to observation of only 632 men however On January , 1967 a larger cohort was enrolled for prospettive observation and included all 17,800 men on the rolls of the insulation workers union International Association of Heat and Frost Insulators and Asbestos Workers AFL CLC in the United States and Canada on that day This second cohort included the survivors of the original 632 New York Jersey men Observation has been maintained and an interval report of deaths in this group since January 1 1967 has been made The present analysis details findings among these men through December 31 1976 ASBESTOS INsulation in the United States Asbestos as a mixture of fiber and sodium silicate was first used as an insulation material in 1866 and as asbestos cement about 1870. Magnesia with asbestos as a binder soon followed and cell covering using corregated asbestos paper was introduced in 1898 The first union of insulation workers in the United States was formed in New York City in 1883 under a charter issued by the Knights of Labor predecessor of the American Federation of Labor as The Salamander Association of Boiler and Pipe Felters The present union of insulation workers in this country as chartered by the AFL in 1910 as the International Association of Heat and Frost Insulators and Asbestos Workers by the amalgamation of the Salamanders Association of New York with other independent locals throughout the country Members of this union are insulation workers primarily employed in the building trades doing construction insulation work but also employed as insulation workers in refineries industrial plants This study was supported by grants from the American Cancer Society 53 the National Institute for Occupational Safety and Health OH00320 and the National Institute of Environmental Health Sciences ES00928 of the U.S. Department of Health Education and Welfare and the Health Research Council of the City of New York U1272 91 0077-8923 1.75 '1979 NYAS Annals New York Academy of Sciences shipyards and powerhouse construction and repair Much of their work is in the open but sometimes as in shipyards in rather tight quarters The men generally work in all parts of the trade with few specialists at one or another part of it Conditions at work vary from job to job and from company to company with fewer than 10 of the men remaining with one company during their working lifetimes Data published concern- ing work practices in other countries suggest that asbestos exposure in insulation work has been approximately the same the world over insulation Asbestos exposure to which workers are subject has been limited varied early and intermittent Some of the materials used have contained no asbestos In the part of the century magnesia pipe coverings used shredded rope as a binder with no asbestos Somewhat later wool cork and rock wool were used Starting during World War II fibrous glass products came into increasing use and during the 1970s bias.Gander their utilization was greatly expanded as asbestos content of insulation materials sharply decreased Magnesia block insulation including molded pipe coverings usually contained approximately 15 asbestos while asbestos cement generally had uae 15-20 or less of asbestos Asbestos paper products contained a higher asbestos clat content but were used in much smaller quantities Until approximately the early 1940s chrysotile alone was utilized in the manufac- ture of the asbestos insulation products used by these men Amosite began to be used MAAN: in the 1930s in small quantities but became more widely utilized during World War and subsequently 2s Few dust counts were made in insulation work until the 1960s However BBL analysis of available data including reconstruction of work situations and extrapola- tion to the past of observations made more recently suggest that insulation workers would have been exposed to dust levels of 4-12 fibers as time weighted TABLE 1A MEMBERSHIP OF NEW YORK AND NEW JERSEY INSULATION Workers Union JanuARY , 1943 CLASSIFIED BY AGE AND YEARS FROM FIRST EXPOSURE TO ASBESTOS DUST Total Age Years 15-19 20-24 25-29 30-34 35-39 40.44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 Total Number Members 2 14 38 122 76 74 77 82 65 41 23 13 3 2 632 0-9 NJON- NJONNJON- NJONNJONI ! 40 Number of Years Since First Exposure to Asbestos 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50+ 19 94 26 7 47 6 -27 * 28 30 -27 ! - 19 29 -27 4 ~ ) 24 * 24 * -A- 4 " -1 20 19 -A- x -1 13 * -A- 2 : i * - 2 * 1 4 4 2 2 2 3 } | 1 145 140 108 70 67 a) 15 1 Locals 12 and 32 of the International Association of Heat and I rost Insulators and Asbestos . Workers AFL Selikoff et al Mortality of Insulation Workers TE 7 A . TABLE IB _ years of Observation January 1 DECEMBER 31 1962 of January . . 1943. MEMBERSHIP OF NEW York and NEW JERSEY INSULATION WORKERS UNION : CLASSIFIED BY ATTAINED Age and Years from First ExPOSURE TO ASBESTOS DUST . Attained o. Age Years . 7. 15-19 ee 20-24 ; Total . years 4 44 20 4 44 Years from Onsei 20-34 _ - 35+ _ _ co oss 30-34 oo _ 40 - ae , ; ; -: 35-39 44 45-49 50-54 , 55-59 60-64 a - 65-69 70-74 75-79 80-84 85+ Total 542 1.068 1.339 1.588 1.562 1.344 1,142 849 513 242 84 29 10,515 542 773 253 74 39 28 22 17 9 _ - 1970 ~ 295 1086 1510 1368 782 361 175 72 33 1 5683 _ -- 4 155 534 759 657 432 209 83 29 4862 International Association of Heat and Frost Insulators and Asbestos Workers AFL averages While there might have been periods of little or no exposure there could also have been times of peak exposures much higher than the calculated averages - fre "are = oo Mortality Experience oF NEW YORk JerseY INSULATION WORKERS 1943-1976 On January 1 1943 there were 632 men registered as members of the two locals of the International Association of Heat and Frost Insulators and Asbestos Workers in the New York Jersey metropolitan area Locals 12 and 32 Their age distribution according to years from onset is contained in TABLE IA and years of observation 1943-1962 are shown in TABLE IB Each of these men was traced to December 31 1962 expected and observed deaths are found in Table 2. Nine men died before reaching 20 years from first employment and they are excluded from TABLE 2 which is limited to the 623 men who achieved that point While deaths related to asbestos exposure of the kind experienced by insulation workers may sometimes occur in less than 20 years from onset of employment lung cancer asbestosis and occasionally mesothelioma these are not common and we consider that analyses of experiences beyond the year point more clearly define the influence of such exposure It was of interest parenthetically that there was no excess in total deaths of all causes during the first 10 years of observation 1943-1952 in the post 20 years from onset experience- an excess was seen for lung cancer specifically as example of the healthy worker effect Observation of the survivors of the original cohort has continued prospectively and by December 31 1976 478 of the original 632 men had died The same overall pattern of causes of death has continued although distribution of deaths by cause has changed Annals New York Academy of Sciences TABLE 2 EXPECTED ANd Observed Deaths Among 623 ASBESTOS INSULATION WORKERS NEW YORK JERSEY 20 OR MORE YEARS AFTER ONSET OF WORK January 1 DecEMBER 31 1962 8545 years of Observation fi Underlying Cause of Death Total deaths causes Total cancer sites Cancer of lung Pleural mesothelioma av Peritoneal mesothelioma Cancer of esophagus stomach rectum Cancer of larynx pharynx buccal cavity Cancer of kidney All other cancer Noninfectious pulmonary diseases total Asbestosis All other causes Expected 195.4 32.1 6.0 + t 97 1.7 os 0.7 14.0 4.0 t 159.3 Observed 253 95 42 3 4 19 2 0 $ 14 12 144 Expected deaths are based upon white male specific U.S. death rates of the U.S. National Center for Health Statistics 1949-1962 Rates for specific causes of death for 1943 194w8ere extrapolated from rates for 1949 1955 . Rates are not available but these have been rare causes of death in the general population somewhat reflecting a number of epidemiological influences Thus pleural and peritoneal mesothelioma which tend to occur somewhat later than bronchogenic carcinoma became proportionately more common Table 3 This change in preponderance also reflects the smaller proportions of older men who ever smoked cigarettes and also a survivor effect Since the cigarette smokers in the original group had TABLE 3 EXPECTED AND OBSERVED Deaths AMONG 632 NEW YORK JERSEY ASBESTOS INSULATION Workers January 1 December 31 1976 13,925 years of Observation ly Underlying Cause of Death Expected Observed Total deaths all causes Total cancer all sites Cancer of lung Pleural mesothelioma Peritoneal mesothelioma Cancer of esophagus Cancer of stomach Cancer of rectum Cancer of larynx pharynx buccal cavity Cancer of kidney All other cancer Noninfectious pulmonary diseases total Asbestosis All other causes 328.9 57.0 13.3 t + 4 5.4 83 2.8 1 3 245 93 + 2020 478 210 93 11 27 1 19 23 6 2 28 5 41 223 Expected deaths are based upon white male specite US death rates of the U.S. National Center for Health Statistics 1949-1976 Rates for specific cause of death for 1943 194w8ere extrapolated from rates for 1949 1955 Rates are not available but these have been rare causes of death in the general population - Sclikoff et al Mortality of Insulation Workers increased mortality risk especially from lung cancer and cardiovascular disease there would likely have been comparatively fewer men with a history of cigarette smoking and : still fewer who continued smoking at least the same amount among the " . cohort survivors as the years went by Except as influenced by other factors associated with advancing lapsed time since onset of asbestos work this would make for fewer | deaths of lung cancer with more men at risk of dying of other associated . iv. disease Lung cancer remained the most important cause of excess deaths with 93 such deaths observed vs. 13.3 expected Thirty eight deaths occurred of mesothelioma 1 11 0 * pleural and 27 peritoneal The increase in gastrointestinalcancer originally reported in 1964 was again seen with 43 deaths observed 15.1 expected There were 41 deaths of asbestosis In addition 4 deaths were observed of other noninfectious pulmonary - diseases Apart from cancer asbestosis and other noninfectious pulmonary diseases . observed deaths were fewer than expected of all other causes only 223 seen 27 7 teos 2 approximately 40 fewer than anticipated L This experience with 19 of deaths due to lung cancer % the result of _ mesothelioma % of gastrointestinal cancer and % of asbestosis and other noninfec- tious pulmonary diseases begins to provide a broad outline of the total mortality experience of insulation workers employed under conditions of the past much less asbestos insulation was used in new construction after 1972 although variable and '_. intermittent asbestos exposure would be expected to have continued to occur during wos , repair work 76 of the original cohort enrolled in 1943 had died by cad of 1976 Among . Variationsin distribution of deaths by cause over time may be seen in TABLE 4 Among the 9 deaths listed before 20 years from onset of exposure there was none of lung cancer mesothelioma gastrointestinal cancer or asbestosis and other noninfec- tious pulmonary diseases Variations are also evident in the two periods 20 3y4ears ; ete . es ~ . and 35 or more years from onset Although the proportion of deaths due to cancer of _ all sites was virtually identical in the two periods 44.5 and 44.3 the specific f neoplasms were quite different in proportional Lung cancer accounted for . distribution 49 of the cancer deathsin the shorter period but only 43later There were 7 deaths } mesothelioma during of inin the 6263 years of observation the 20 3y4ear span but \ 31 such deaths in the 5692 years later on It of interest 100 that the proportion ' | of mesotheliomas that were pleural in location also changed over time 4 of the 7 were pleural in the earlier period against only 7 of 31 in the second period It is clear that unless opportunity for prolonged observation is available it will be difficult to fully evaluate the distribution of deaths by cause among asbestos exposed groups Concomi- \ tantly such analysis will be enhanced by considering deaths in each period of duration from onset separately Not unexpectedly deaths of asbestosis were again largely concentrated in the 35 or more years from onset period 38 of the 41 such deaths were found at this time It has been of interest to inquire concerning the experience of those insulation workers whose exposure began after 1943 since this would reflect postwar conditions Eight hundred and ninety men joined the New York Jersey metropolitan area locals of the union during the period January 1 December 31 1962. Most 833 had had no prior asbestos employment before entering the union These men have been observed prospectively from the time of admission to the union to December 31 1976 Tab~...es5A and 5B Our experience with their 1943 predecessors had demonstrated that we were to expect relatively few deaths before 20 years from onset of their work Still because of the importance of evaluating postwar experience among men not exposed in earlier years we undertook this study Table 6 details their mortality experience from first employment to December 31 1976. In the 15,520 years of observation during the less than year period there was no unusual mortality experience Altogether there were fewer deaths than expected again the healthy TABLE 4 EXPECTED AND OBSERVED DEATHS AMONG 632 New YORK JERSEY ASBESTOS Insulation WORKERS January DECEMBER 31 1976 Number of Men Attaining Category years of Observation Underlying Cause of Death Total deaths all causes Total cancer all sites Cancer lung Pleural mesothelioma Peritoneal mesothelioma Cancer esophagus Cancer stomach Cancer colon rectum Cancer larynx pharynx buccal cavity Cancer kidney All other cancer Noninfectious Noninfectious pulmonary discases total Asbestosis other causes Less than 20 Years 325 1970 Expected 9.0 1.1 0.2 f + 0.02 0.1 0.2 Observed a20 a20 a200 a200 0 0 0 0 0.05 2 0.03 0 0.5 0 0.1 JOO t JOO 7.8 JOO 20 Years 561 6263 * Expected 80.4 13.5 3.0 t 0.4 1.5 1.9 Observed 119 53 26 4 3 0 6 7 0.8 NOS 0.4 NOS . 5.5 5 - 1.6 432 + 432 65.3 432 35 or More Years 498 Anals 5692 Expected Observed New 239.5 350 42.4 155 10.1 67 York 3 7 24 1.0 I Academy 3.8 13 6.2 16 1.9 223 of 09 223 18.5 223 Sciens 7.6 41 t 38 189 5 154 Expected deaths are based upon white male specific U.S. death rates of the U.S. National Center for Health Statistics 1949 1976. Rates for specibe causes of death for 1943 1948 were extrapolated from rates for 1949 1955 Rates are not available but these have been rare causes of death in the general population Cadi blede ainracle Sith TABLE SA NEW YORK AND NEW Jersey InsulATION WORKERS OBSERVED January , DECEMBER 31 1962 AND SUBSEQUENTLY TO DECEMBER 31 1976 Number of Men Attaining Category 1943 ~ . ay To ae . Union Members Jan. , 1943 : Years from Onset Period Total 1943-1952 1953-1962 542 1963-1969 370 . 1970-1976 234 20 325 40 = 20-34 523 393 154 32 35- 190 321 328 224 Men Joining Union 1943 Years from Onset Total 20 20-34 412 833 828 811 412 833 828 561 258 51 1962 35 _ _ _ TABLE SB YEARS OF OBSERVATION OF NEW YORK AND NEW JERSEY INSULATION WORKERS 1943-1976 Number of years Period 1943-1952 1953-1962 1963-1969 1970-1976 Union Members Jan. 1 1943 Years from Onset Total 5928 4587 2088 1322 20 1682 288 - 20 34 3253 2430 418 162 35- 35- 993 1869 1670 1160 Men Joining Union 1943-1962 1943-1962 Years from Onset Total 1658 906 5752 5485 20 1658 5906 5156 2800 20-34 vee _ 596 2685 35- _ TABLE 6 EXPECTED ANd Observed Deaths Among 833 New York JERSEY ASBESTOS INSULATION Workers First Employed January 1 December 31 . AND OBSERVed from First Employment 31 1976 1962 Duration from Onset of Employment Number of Men Attaining Category years of Observation Underlying Cause of Death Total deaths all causes Total cancer all sites Cancer of lung Pleural mesothelioma Peritoneal mesothelioma Cancer of esophagus stomach rectum Cancer of larynx pharynx buccal cavity Cancer of kidney All other cancer Noninfectious pulmonary diseases total Asbestosis All other causes Less than 20 Years 833 15.520 Expected 39.8 5.1 1 t t Observed 23 5 NOO NOO NOO 20-34 Years 523 3281 Expected 24.8 5.0 1.8 t t Observed 39 15 8 2 1 0.7 1 0.8 2 0.2 1 0.3 I 0.1 i) 0.1 1 3.0 ! 2.0 0 0.5 0 0.6 7 + 0 + 6 34.2 18 19.2 17 Expected deaths are based upon white male specific U.S. death rates of the U.S. National Center for Health Statistics 1949-1976 Rates for specific causes of death for 1943 194w8ere extrapolated from rates for 1949 1955 Rates are not available but these have been rare causes of death in the general population Annals New York Academy of Sciences worker effect and there was no increase in cancer deaths No mesotheliomas were seen nor deaths of asbestosis There was no significant increase of either lung cancer or gastrointestinal cancer Since the year point we have begun to see the changes predicted by our earlier studies In the 3281 years of observation 20 3y4ears from onset there were approximately three times as many cancer deaths as expected primarily due to lung cancer Mesotheliomas were now first seen and some deaths of asbestosis occurred These had occurred primarily during the period 1970 1976 TABLE 7 When the 1943 workers were compared with those first exposed before that time and evaluation was limited to obs ationsless than 20 years from first exposure it was found that neither group had unusual lung cancer mesothelioma or asbestosis experience TABLE 8 demonstrates that among 325 World War II men who had not reached 20 years from onset of exposure during their period of observation covering 1970 years no excess of these diseases was seen Similarly among the 833 war men with 15,520 years of observation during the shorter than year from onset point and with exposures starting 1943 196n2either mesothe- lioma nor asbestosis deaths occurred and there were not significant excess deaths of lung cancer This is of interest in that by and large only chrysotile exposure had occurred before 1943 for the first group while amosite was added to chrysotile in terms of potential exposure from 1943 on The after group was potentially exposed to both types of asbestos throughout their work experience These data indicate that amosite did not shorten the period of clinical latency for asbestosassociated disease in these insulation workers Further taken together with the data in Tables 6 and 7 these observations suggest that the mortality experience of insulators exposed to both chrysotile and amosite will be in the same direction as those originally exposed only to chrysotile and later to insulation dusts also containing amosite Table 9 reviewing deaths of selected causes 20-34 years from onset in the 1943 group and comparing the findings with observations in the 1943 group for the same time span suggests that this will be the case Mortality Experience of InsulatoRS IN THE UNITED STAtes and Canada 1967-1976 There were 17.800 men on the rolls of the asbestos workers union in the United States and Canada on January , 1967 A good deal of information concerning these men was available including date of birth date of first insulation work employment status on January 1 1967. Additional information was obtained by questionnaire from a majority of the men concerning current symptoms respirator use smoking habits work practices We have maintained observation of this cohort since 1967 with the valuable assistance of the local and international officers of the union The men are registered in approximately 120 local unions in the various parts of the United States and Canada including Alaska and Hawaii Whenever an insulation worker associated with the union dies we are notified In most instances a death certificate certificate is forwarded if not it is obtained As with the New York Jersey group information is then sought concerning the details of the circumstances of death including clinical data roentgenograins histological obtained at surgery or autopsy The chnical and International Association of Heat and Frost Insulators and CLC Asbestos Workers AFL CO CO n Ce Te pa oae oy abnitn de dK Pancha DAM bay el a Se Selikof TABLE 7 et EXPECTED AND OBSERVED DEATHS AMONG 833 NEW YORK AND NEW JERSEY ASBESTOS ^ NSULATION WORKERs First EmptOYED JANUARY , 1943- DECEMBER 31 1962 AND OBSERVED FROM FIRST EMPLOYMENT DECEMBER 31 1976 al Noninfectious 1943 1952 Mortaliy Lung Lung CaCnacnceerr Expected Observed Pleural Mesothelioma Peritoneal Peritoneal Mesothelioma Pulmonary DDiiseeaasseses ToTtoatlal * Expected Observed Asbestosi Asbestosis Observed of ( 0 0.0 1953-1962 02 0 0 1963-1969 0 1970-1976 2 Insulation 0.2 Insulation 0.3 Insulation 0.6 S Insulation Expected deaths are based upon white male male specific U.S. death rates of the U.S. National Center for Health Health Statisties 1949 1976. Rates for Insulation 1943-1948 were extrapolated from rates for 1949-1955 Workers Workes wir ie estiers ise i peiatomtonam: says er Es, het WS TABLE 8 C$ Anals fa SELECTED CAUSES AMONG 632 NEW YORK NEW JERSEY ASBESTOS ASBESTOS INSULATION WORKERS FIRST EXPECTED AND OBSERVED DEATHS OF DECEMBER DECEMBER 31 1962 OBSERVED OBSERVED FROM EMPLOYED BEFORE BEFORE JANUARY , 1943 AND 833 WORKERS FIRST EMPLOYED JANUARY 1 JANUARY 1 1943 OR DATE OF FIRST EMPLOYMENT 31 1976 New Deaths from Selected Causes Less than 20 Years from First Exposure to Possible Amosite and or Chrysotile Asbestos Exposure Mesotheliomat Noninfectious Asbestosist Oe Lung Cancer Diseases York Less than 20 Years from First 1 sposure to Number of Men in Category years of Observation rr Rate per 1000 Exp Obs Obs years PulmonaryPulmonary Tot Exp > Obs Obs Rate per 1000 years Chrysotile only before Academy 1943. pans afnosite after 1943 325 0 1,970 0.2 0 0 0 0.1 0 ) of of spesied Scien s RK Mysound and Anve 833 15,520 7 spesied deaths are based upon white male specific U.S. 1.1 2 0) 0 0 death rates of the U.S. National Center for Health Statistics 1949-1976 1949-1976 0 Rates for 1943-1945 1943-1945 were extrapolated from rates for 1949 1955 Sciences Rates available but these have been rare causes of death in the general population #Amiosite insulation materials materials were first introduced shortly before and during World War El we No ante Linares is: nbonetoth TABLE 9 EXPECTED AND OBSERVED DEATHS OF SELECTED CAUSES AMONG 632 NEW YORK JERSEY ASBESTOS INSULATION WORKERS FIRST EMPLOYED BEFORE JANUARY , 1943 AND 833 WORKERS FIRST EMPLOYED JANUARY 1 DECEMBER 31 1962 OBSERVED FROM JANUARY 1 1943 OR DATE OF FIRST EMPLOYMENT DECEMBER 31 1976 Deaths of Selected Causes 20 34 Years from Onset of Exposure Selikof Mesothelioma Noninfectious Asbestosist et First Exposure Number of Men in years of Lung Cancer _ Lung Cancer Rate Pulmonary Total per 1000 Diseases Total Rate al per 1000 Category Observation Exp Obs Obs years Exp > Obs Obs years Mortaliy Before 1943 1943-1952 523 3253 0.31 1953-1962 393 2430 1.65 1963-1969 154 418 2.39 of 1970-1976 32 162 6.17 Total 561 6263 Insulation 1943-1962 1943-1952 1953-1962 1963 1969 258 1970-1976 515 Workers Workes Total 523 Expected deaths are based upon white male specific U.S. death 1943 1948 were extrapolated from rates for 1949 1955 Rates are not available but these have been rare causes of death in the general population Annals New York Academy of Sciences TABLE 10 . MEMBERSHIP OF ASBESTOS Insulation WORKERS UNION JANuary 1. CLASSIFIED BY AGE AND By Years from First ExPOSURE TO ASBESTOS 1967 DUST Total Age Years Number Members 0-9 Number of Years Since First Exposure to Asbestos 10-14 15-19 20-24 25-29 30-34 35-39 40-49 50+ 15-19 244 244 20-24 1.695 1695 25-29 2.412 2066 345 l 30-34 35-39 2,762 2.988 1065 313 1356 1141 341 1342 192 2,260 79 424 1026 591 139 1 40-44 45-49 1.589 131 433 3 487 +7 77 1.297 27 88 214 332 377 182 50-54 55-59 984 13 49 129 206 176 146 193 72 amhlit 703 \ 21 59 131 126 87 99 179 60-64 65-69 419 6 18 +1 58 45 29 201 21 7 6 14 22 21 16 105 71 255 _ 70-74 tf 75--79 111 -- \ 4 8 F 7 37 50 - - 2 \ 2 16 31 52 80-84 2 7 20 shbaie's Total 85+ 29 17,800 5552 3562 3569 1953 534 425 193 tomes Membership in the United States and Canada of the International Association of Heat and iden CLC bide) Frost Insulators and Asbestos Workers CIO ie, roentgenological roentgenological data are reviewed and the pathological material examined Most of go the presentation for for this cohort is in terms of underlying cause of death categorized ey according to best evidence available BE Further details are also given in the tables for underlying cause assigned on the basis of death certificate information only DC be At the outset of the study a majority of the men were below the age of 40 10.101 of 17,800 The majority too had yet to achieve 20 years from first exposure 12,683 of 17,800 TABLE 10 During the period January , December 31 1976 the cohort changed its age and duration from onset distribution with the passage of time Many of the men who started in the less than 20 year from onset group achieved 20+ years from onset during the decade of observation TABLE 11 Altogether 12,683 men with 89,462 years of experience suffered 325 deaths in the period before 20 years There TABLE 11 OBSERVATION OF 17,800 ASBESTOS Insulation WoRKERS and Canada January , DECEMBER IN THE United United 31 1976 States Number of men years of observation Deaths Average age during observation Total 17,800 166.857 166.857 2,271 44 20 Years from Onset 12,683 89,462 89,462 128 i 20+ Years from Onset 12,051 77.391 77.391 910 wT : 2. : - an Selikoff et al Mortality of Insulation Workers 103 occurred 1946 deaths among 12,051 men who had achieved 20+ with 77,391 years of observation The years from onset average age during observation was 36.3 . years for the shorter group and 53.8 years for those with longer duration from onset During the decade of observation 2271 deaths occurred TABLE 12 whereas 1658.9 deaths were expected based upon white male only U.S. National Center for Health age specific mortality data of the result of an increased Statistics The excess deaths were primarily the number of instances of cancer of several sites Investigation of the deaths found 486 due to bronchogenic carcinoma between 4 and 5 number anticipated There were 175 deaths of times the mesothelioma 63 pleural in location Spas : . ae _ ; KYa ; Deaths TABLE 12 among 17,800 ASBESTOS Insulation Workers AND CANADA JANUARY 1 1967 December in the United 31 1976 NUMBER OF MEN 17,800 YEARS OF OBSERVATION 166.853 StATES Underlying Cause of Death Total deaths all causes Total cancer all sites Cancer of lung Pleural mesothelioma Peritoneal mesothelioma Mesothelioma n.o.s. Cancer of esophagus Cancer of stomach Cancer of rectum Cancer of larynx Cancer of pharynx buccal Canceorf kidney All other cancer Noninfectious pulmonary diseases total Asbestosis All other causes Expected * 1658.9 1658.9 319.7 105.6 t 7 + 7.1 14.2 38.1 4.7 10.1 8.1 131.8 59.0 1 1280.2 Observed BE DC 2271 995 486 43 12 0 13 22 59 | 21 19 184 2271 921 429 15 24 55 18 18 58 9 16 18 252 212 168 1064 188 78 1161 Ratio ak) 1.37 3.11 4.60 DC 137 2.38 4.06 _ 2.53 1.54 1.55 2.34 2.08 2.36 1.40 oe 2.53 1.26 1.52 1.91 1.59 2.23 1.91 3.59 - 0.83 3.19 . 0.91 Expected deaths are based upon white male specific National Center for Health Statistics 1967-1976 U.S. death rates of the U..S Rates are not available but these have been rare causes of death in the general population BE Best evidence Number of deaths categorized after review of best available information information autopsy surgical clinical DC Number ofdeaths as recorded from death certificate information only and 112 peritoneal There was a modest increase in deaths of gastrointestinal cancer esophagus stomach rectum Cancers of several other sites were also significantly increased over the number expected There were 11 deaths of cancer of the larynx 21 of the buccal cavity and pharynx as well as 19 deaths of cancer of the kidney In each instance this was twice the number anticipated Comment had previously been made interest in these sites but at the time there concerning were inadequate data for evaluation Additional experience has indicated that the early hints were predictive Review of information concerning the deaths allowed a distinction to be made between deaths caused by asbestosis and those of other noninfectious pulmonary 104 ~ Annals New York Academy of Sciences diseases including emphysema and cor pulmonale Thereby 168 deaths were assigned to asbestosis and 44 were attributed to other noninfectious pulmonary diseases compared with a total expectation of 59.0 in the general population The question of whether noninfectious pulmonary diseases other than asbestosis are or are not increased in asbestos workers is a complex problem Continuing questions of nomen- clature of chronic obstructive lung disease in general and uncertainties of designation and pathological categorization were recently well reviewed by C. M. Fletcher Chronic nonspecific lung disease particularly that due to cigarette smoking may have an influence on the course of the asbestosis providing an added burden to damaged lungs We have evidence that there is such influence On the other hand diffuse interstitial parenchymal fibrosis diffuse pleural fibrosis would be disadvan- tageous for individuals with extensive chronic obstructive lung disease particularly with superimposed pulmonary infections or other physiological stress Such disadvan- tageous additional contributions in individual cases may play important roles in determining the adequacy of a patient's respiratory rese eCategorizing deaths in terms of a single underlying cause however does not allow for inclusion of nuances of interaction among the several factors nor to depict the full spectrum of such interacting disease from cases in which little other than asbestotic pulmonary fibrosis may be involved to those in which all evidence indicates that cigarette smoking and bl chronic obstructive lung disease were the principal factors 0b For causes other than cancer and asbestosis and other noninfectious diseases there were fewer deaths than expected 1064 against 1280.2 In particular there were fewer bande deaths of arteriosclerotic cardiovascular disease and its consequences This is further te nar considered elsewhere and it may well be that the active physical work associated with employment as insulation workers is advantageous in preventing or delaying death of Cees aches cardiovascular disease although the influence of initial selection upon admission to the trade cannot be disregarded It is evident that most excess deaths in this cohort were due to cancer 675 rather OE than to asbestosis and other noninfectious pulmonary diseases 153 This is notewor- Teac thy since the present United States Standard for occupational exposure to asbestos is in large part derived from reported recommendations designed to prevent asbestosis a PIRES Deaths of LESS COMMON MALIGNANT NEOPLASMS Apart from lung cancer mesothelioma gastrointestinal cancer cancer of the larynx pharynx and oral cavity and cancer of the kidney there was still as excess of cancer of other sites with 184 observed compared with 131.8 expected TABLE 13 provides information concerning expected and observed deaths for a number of other sites For some there was no evidence of increased incidence as with leukemia lymphoma primary cancer of the liver testes bladder Relatively small increases were suggested for brain skin pancreas prostate The overall increase is of some interest especially in view of the known possibility of asbestos fibrils being disseminated to virtually all organs following inhalation or ingestion We have long been properly accustomed to seeking verification of increases beyond chance expectation statistically significant in incidence of cancers of defined sites This perspective does not contradict the potential importance of more general increases in cancer incidence of a large variety of sites perhaps not teaching levels of statistical significance in any one location but still yielding definite increases of the overail cancer burden of the groups investigated Selikott et al Mortality of Insulation Workers MULTIPLE CANCERS From a purely statistical point of view in view of the increased incidence of cancer of several sites among asbestos insulation workers we would would expect that a proportion of these men would suffer multiple cancers simultaneously even beyond the tendency of such findings to be made among individuals with cancer in general Again this would not be reflected in tabulations of causes of death by single underlying cause as is the usual practice Analysis of our experience demonstrated one hundred malignant neoplasms present but not causing death TABLE 14 Sometimes these additional neoplasms were mentioned on the death certificate but as an other significant . condition not in the section on the underlying cause of death Forty were present among the 1064 cases where death was due to causes other than cancer or asbestosis Table 13 DEATHS AMONG 17,800 ASBESTOS Insulation WoRKERS AND CANADA January 1 1967 DECEMBER NUMBER OF MEN 17.800 IN THE United StATES 31 1976 +s YEARS of ObservatION 166,853 Underlying Cause of Death Total deaths all causes Cancer all sites Deaths of less common malignant neoplasms Pancreas Liver biliary passages Bladder Testes Prostate Leukemia Lymphoma Skin Brain Expected 1658.9 319.7 17.5 7.2 9.1 1.9 20.4 13.1 20.1 6.6 10.4 Observed BE DC 2271 995 2271 922 Ratio e BEE DC 1.37 3.11 1.37 2.58 23 707-3 1.32 2.81 S 707-3 0.70 2.65 9 707-3 0.99 0.77 2 70-3 _ _ 30 28 1.47 1.37 15 15 1.15 1.15 19 16 0.95 0.80 12 ' 1.82 1.22 14 17 1.35 1.63 Expected deaths are based upon white mate specific U.S. death rates of the U.S. National Center for Health Statistics 1967-1976 BE Best evidence Number of deaths categorized after review of best available information autopsy surgical clinical DC Number of deaths as recorded from death certificate information only TABLE 15 Among the 168 deaths of asbestosis cancer was also present in 7 6 of these being bronchogenic carcinoma Analysis of the circumstances leading to death however indicated that the underlying cause was asbestotie pulmonary insuficiency and that the lung cancers were present but with no decisive influence at the time of death Nineteen other cancers were present among the 486 deaths of lung cancer and 10 other cancers accompanied the 175 deaths of mesothelioma There were 9 incidental neoplasms among the 99 deaths of gastrointestinal cancer Although experiences are so far limited it may not be wholly unexpected that there were proportionately more incidental neoplasms accompanying deaths of rectum cancer compared to those of lung cancer 8.5 vs. 3.9 One may speculate that this 106 Annals New York Academy of Sciences TABLE 14 MORTALITY STATES EXPERIENCE AMONG 17,800 ASBESTOS INSULATION WORKERS IN AND Canada 1967-1976 OBSERVATIONS IN 2271 CONSEcutive CONSEcutive the United DeaTHS Malignant Neoplasms Present but not Causing Death Site Number Lung Pleural mesothelioma Peritoneal mesothelioma Esophagus Stomach Colon Oropharynx Larynx Kidney Other v^' 24 2 i 0 ' 19 3 ; 3 att ao Twenty of these neoplasms were mentioned on the death certificate but were not categorized as underlying cause of death Including leukemia 3. lymphoma 3 bladder 5 prostate 13 thyroid etc. Ys ma In 92 individuals total includes multiple cancers in eight cases mstibes: men could be due to the longer clinical course of many patients with rectum cancer thek compared to lung cancer with greater opportunity simply in terms of time to develop additional disease heplrbt Multiple cancers were present present overall in 2.1 of deaths among these asbestos vers insulation workers 48 of 2271 It is perhaps to be expected that this was more likely to be the case among those for whom cancer was was the primary cause of death 4.57 while only 3 of the 1276 other deaths had this finding From a clinical point of view in the management of patients with asbestos- associated disease the potential for incidental or multiple cancers is of some and awareness of the possibility may assist in both the diagnostic importance individuals with history of significant investigation and term surveillance of asbestos exposure Lapsed Per It is now well appreciatedapreciated that most asbestos associated discase is first seen after considerable periods from onset of exposure in both occupational and environmental circumstances This is true both for the presence and extent of parenchymal fibrosis a presnce and pleural fibrosis and calcification and for associated neoplasms pet, Data obtained in this investigation now provide a more complete overview of this question Broadly we saw some limited excess disease in less than 20 years from onset of exposure Table 16 Among 12,683 men with such experience covering 39,462 years of observation the number of cancer deaths was about doubled with 42.6 deaths expected and 83 observed There were no excess deaths of gastrointestinal cancer and only 5 deaths of mesothelioma with these in the 15. 19 years from onset category Age year year and sex specilie mortality data of the U.S. National Cancer for Health Statistics indicated that 11.9 deaths of lung cancer were be expected Thirty occurred There were 8 deaths of asbestosis Selikoff et al Mortality of Insulation Workers 107 On the other hand extensive disease was seen among the 12,051 men who had reached 20 or more years from onset during the decade of study Here 1376.0 deaths were anticipated 1946 occurred There were 160 deaths of asbestosis and 912 of cancer It was at this time that bronchogenic carcinoma made its heaviest contribu- tion with 93.7 such deaths expected and 450 observed One hundred and seventy deaths of mesothelioma were then seen and the increase in gastrointestinal cancer found TABLE 17 depicts these data in some detail in year periods from onset of employment Lung cancer data are given as both expected and observed numbers of death This practice cannot be followed for mesothelioma where expected deaths cannot be computed for the general population Instead we have provided data in both number of deaths of pleural and peritoneal mesothelioma as well as in terms of number of deaths of these causes per thousand persons years at risk The latter does not take into account variations in achieved age but this may have less influence than achieved duration from onset of employment It will be seen that very major increases in numbers of deaths of lung cancer are first seen at 15-24 years from onset of work with continued further increases The extraordinary increase in deaths of mesothe- lioma both of the pleura and the peritoneum is not observed until somewhat later reaching 2.78 deaths per thousand person at risk for pleural mesothelioma at 35-39 years from onset of work and 5.47 deaths of peritoneal mesothelioma per thousand person at 45+ years from onset In another reflection of the clinical concerns among these workers TABLE 18 indicates that approximately third of all deaths were due to lung cancer at 30 34 years from onset while mesothelioma accounted for 13 of all deaths at 35 3y9ears TABLE 15 Mortality Experience AMONG 17,800 ASBESTOS Insulation Workers in the United States and Canada 1967-1976 OBSERVations in 2271 CONSECUTIve Deaths NUMBER OF INcidental Malignant NeoPLASMS NOT Causing Death in RelatioN to Underlying Cause of Death as EstTABLISHED BY BEST EVIDENCE BE Underlying Cause of Death ~ Cancer sites Cancer of lung Pleural mesothelioma Peritoneal mesothelioma Cancer of esophagus Cancer of stomach Cancer of rectum Cancer of larynx Cancer of pharynx buccal cavity Cancer of kidney All other cancers Noninfectious pulmonary discases total Asbestosis All other causes Total Number Number of Deaths of Underlying Cause 995 486 63 112 18 22 59 11 21 19 184 212 168 1064 2271 Incidental Malignant _- NeopNeopiaisms asms No. of Total Deaths Cancers 45 50 17 19 4 4 5 6 1 ; 3 3 S S 0 0 2 3 0 0 8 9 0722 10 0722 7 0722 40 91 100 Six of these were lung cancer TABLE 16 DEATHS AMONG 17,800 ASBESTOS INSULATION WORKERS IN THE UNITED STATES AND Canada JANUARY , 1967 DECEMBER 31 1976 ANALYSIS BY DURATION FROM ONSET OF EMPLOYMENT Total Men years of Observation Underlying Cause of Death deaths all causes Cancer all sites Cancer of lung Pleural mesothelioma Peritoneal mesothelioma Mesothelioma 0.0.5 Cancer of esophagus Cancer of stomach Cancer of rectum Cancer of larynx Cancer of pharynx buccal Cancer kidney other cancer Nemnfections pulmonary diseases total Asbestusix Asbestusix Aibotlier caFUNCN Before 20 Years from Onset 20 or More Years from Onset 12,683 12,051 89.462 77,391 Anals Expected Observed BE DC Ratio ofe BE) DC * Expected Observed BE DC Ratio ofe BE DC 7 282.9 42.6 11.9 t t t 325 325 83 77 36 32 2 3 0 1.15 1.15 1.15 1.95 1.95 1.81 3.03 3.03 2.69 New 1376.0 277.1 1946 1946 1.41 1.4 912 845 3.29 3.05 93.7 450 397 4.81 4.24 t 7 t 61 23 Ld York 109 24 0 54 | 0.6 | 1.5 0 4.1 17 17 2.64 21 18 54 1.65 1.65 Academy 0.4 4 1.3 3 1. 3 1 21.7 28 30 234 1234 237 101 2.05 2.057 of 14 15 Sciens 222 177 Sciences 76 924 1.79 * Expected deaths are based upon white male specific U.S. death death rates of the U.S. National Rates are not available but these have been rare causes of death in the general population Center for Health Statistics 1967 1976 BF Best evidence Number of deaths categorized after review of best available information autopsy surgical chnical DC Number of deaths as recorded from death certificate information only ich Lind Ath al uy AN ihicigitcibdcdolt Attnats 3 TABLE 17 Selikof DEATHS AMONG 17,800 ASBESTOS InsulatioN WORKERS IN UNITED STATES and Canada January 1 1967- DECEMBER 31 1976 ANALYSIS BY DURATION FROM ONSet of EmplOYMENT Pleural Mesothelioma Peritoneal Mesothelioma et Duration from Number Person of Observed Ratio Ratio ofe No./1000 No./10 No./1000 Person al No 1000 Person Number years _ Number years Onset Years of Men Observation Exp BE DC BE DC BE DC BE HE DC BE 10 Mortaliy 10-14 15 19 0 20 24 8,190 26.393 0.7 0 0 - 0 9.063 29.003 2.7 7 S 2.55 0 9.948 34,066 8.5 29 27 3.40 2 8.887 31.268 31.268 17.0 59 57 3.48 6 ) 0 0 0 0 ) 3 0.09 3 2 0 10 6.596 20.657 21.0 105 96 5.00 58 13 3.547 112 65..0688 3 2,020 11,598 5,403 18.4 11.5 65 57 5.59 9 4.98 15 1.108 1,448 3,160 5.305 8.1 40 131 4.93 17.8 69 53 3.89 4 4 3 6 Insulation 6 19 092 23 1.98 19 S 3.52 16 5.06 19 5.47 Workers 1976 Worke s Expected deaths are based upon white male specific U.S. death rates of the U.S. National Center for Health Statisties 1967 1976 taken into account BI Best evidence Number of deaths categorized after review of best available information autopsy surgical clinical Smoking DC Number of deaths as recorded from death certificate information only Py * + Annals New York Academy of Sciences . TABLE 18 DEATHS AMONG 17,800 ASBESTOS INSULATION WORKERS IN THE United CANADA JANUARY 1 December 31 1976 ANALYSIS By Duration FROM ONSET of EmploYMENT States AND Percent of All Deaths Mesothelioma Years Years from Employment 10 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45+ Total Total Deaths 51 85 189 320 388 340 253 203 442 2271 Lung Cancer BE 0 8.2 15.3 18.4 27.1 32.9 25.7 19.7 15.6 21.4 DC 0 5.9 17.8 24.7 30.3 22.5 15.3 12.0 18.9 Pleural Peritoneal BE 0 " 1.9 3.4 1.7 5.9 2.0 3.2 2.8 DC BE DC 0 0 C Q 0 ul 1.6 1.3 0.9 0.6 13 4.9 0.8 0.9 68 S 1.6 7.5 2.0 1.5 7.9 3 0.9 6.6 Ld 1.1 4.9 at Total By DC ui + > Ls <3 4 (24 a ur 77 a i] 1.6 28 S22 6.5 7.9 6.4 4.1 4.6 Total includes mesothelioma not specified as either pleural or peritoneal BE Best evidence Number of death categorized after review of best available information ren autopsy surgical clinical Teter DC Number of deaths as recorded from death certificate information only eras Altogether lung cancer was responsible for 21 of all deaths observed by us in this eee cohort and mesothelioma for % rere fae INVESTIGATION and CATEGORIZATION OF CAUSEs of Death oy considerable It is widely known that causes of death as recorded on death certificates may be in error and that even when accurate these may be coded with considerable variation among different agencies despite the existence of agreed upon international rules and recommentations Yet death rates based upon large series of causes of death as recorded on death certificates are nevertheless useful and are widely utilized This distinction however leads to the understanding that comparisons between observed stared causes of death and those expected from national or local death rates should not be considered in rigid exact terms especially when considering the mortality experience of very specific groups For these there are no perfect controls that would take into account their age distribution ethnic derivation smoking habits economic circum- ashi stances prior personal and social history and so on det The matter is further complicated by the fact that deaths in the general population which provide the basis for established comparison death rates are not verified by investigation or examination of available data concerning the circum- stances associated with the deaths Of course one may elect to treat the deaths in the study population in exactly the same way with no attempt to review data other than that recorded on the death certificate explicitly accepting whatever whatever errors might exist in causes of death recorded and implicitly hoping that whatever errors exist are very much the same in the two sets of data deaths in the general population and those in the group under investigation Certainly this latter method is simpler cheaper much less time consuming Selikoff et al Mortality of Insulation Workers But this approach has a number of drawbacks First where the distribution of causes of death in the group being studied is different than that found in the general population one may expect that the distribution of inherent error might also be different Second data may be available which can shed much light on the causes of death under investigation and not including such information permits the risk of reporting results which are simply inaccurate It is perhaps inadequate comfort to skirt this difficulty by clearly stating that only death certificate diagnoses are reported this only gives the reason for potential inaccuracy There are also technical issues and these are of particular concern among exposed groups in the sixth seventh and eighth revisions of the International Classification of causes ofdeath There have been no clear categories for the diffuse malignant mesotheliomas of the pleura and peritoneum which occur and while some improvements have been made in the ninth revision now being introduced we fear that these will still not resolve the problem Just as there are no perfect controls there is also no single perfect solution and it is unlikely that there will be such in the foreseeable future especially Since data available for ascertainment of cause of death even when investigations during life and at autopsy have been undertaken are not always complete and are surely not uniform TABLE 19 MORTALITY EXPERIENCE AMONG 17,800 ASBESTOS INSULATION WORKERS IN THE United StaTES AND CANADA 1967-1977 OBSERVATIONS IN 2271 CONSECUTIVE Deaths with Underlying CAUSE OF DEATH CODED According to DEATH CERTIFICATE InformatION ONLY AND ACCORDING 10 Best EVIDENCE Underlying Cause of Death Cancer all sites Cancer of lung Pleural mesothelioma Peritoneal mesothelioma Mesothelioma n.o.s. Cancer of esophagus Cancer of stomach Cancer of rectum Cancer of larynx pharynx buccal cavity Cancer of kidney Cancer of prostate Cancer of bladder Cancer of pancreas Cancer ofliver Cancer of brain Noninfectious pulmonary diseases total Asbestosis other causes Expected 319.7 105.6 + t t 7.1 14.8 . / 20.4 9.1 17.5 72 10.4 59.0 + 1280.2 Death Certificate Best Evidence No.DC No. e No. ose 922 429 25 24 55 ****** ****** ****** 2.88 4.06 _ _ - 2.53 1.26 1.52 995 486 63 112 0 - flfl 59 3.11 4.60 _ 2.53 1.54 1.55 ****** 1.69 ****** 2.23 28 1.37 7 0.77 49 2.81 19 2.65 17 1.63 32 2.16 19 2.36 30 1.47 9 0.99 23 1.32 S 0.70 14 1.35 188 78 61 3.19 _ 0.91 212 168 1064 3.59 . 083 of Evidence 2882 2882 2882 2882 100 82 98 78 95 93 78 213 380 +21 89 46 109 Expected deaths based on white male Center for Health Statistics 1967-1976 specific L.S. death rates of the U.S. National Rates not available but these have been rare causes of death in the generat population population BE Best evidence Number of deaths categorized after review of best availabie information DC Number of deaths as recorded from death certificate information only ee 112 Annals New York Academy of Sciences #9 el We have elected to approach this problem by providing data in more than one way including causes of death as recorded on the death certificate in our cases for THe comparison with expected deaths based upon the data of the U.S. National Center ee for Health Statistics as well as causes of death established after detailed review of all Se oe: available information Such data were retrieved in 1961 of the 2271 deaths However we detailed information was not equally available for all categories of causes of death This was to be expected in the nature of things As a rule the best available a information for establishing the cause of death was considered to be autopsy findings eee Set with pathological information derived from surgical intervention next and in their ee absence clinical and roentgenological observations made during life particularly in the period before death Where no such details were available the cause of death as recorded from death certificate information was then utilized Among the 995 cases of cancer we were required to depend upon the death certificate alone in only 28 with other information available in 967 cases 977 In all 175 cases of mesothelioma surgical and autopsy findings were utilized We depended upon death certi^-cate information alone in 10 of the 486 cases of lung cancer Similarly in 166 of 168 deaths of asbestosis information was available in addition to the death certificate leaving dependence of the latter in only % In contrast f^r causes other than cancer and asbestosis additional information was available in only quarters of the cases Analysis of the distribution of deaths within this category showed that this was by no means unexpected Sudden death attributed to myocardial infarction or cerebrovascular accident is often not further investigated nor need clinical abnormalities have preexisted It was therefore no surprise that in 156 cases the medical attendant or the medical examiner warranted such death certificate diagnosis without other information being available It would seem difficult to avoid differences in quality of ascertainment under such varied circumstances ot! Analysis of our data suggests that by and large death certificate diagnoses were not far off the mark This speaks highly for the diagnostic acumen and quality of care tnd dac provided to these men by their medical attendants Cancer as the underlying cause of Yeon Siseald death was indicated by the death certificate in 922 instances compared with 955 so categorized after considering all available information TABLE 19 The specific a diagnosis of cancer of the lung and cancer of the several sites of gastrointestinal bit cancer as well as cancer of the larynx pharynx and kidney was also generally well predicted by the death certificate diagnosis In number of instances however there was important disparity between causes of death as recorded on the death certificate and those judged to be the case after review of available clinical and pathological material This was true for pleural and peritoneal mesothelioma asbestosis cancer of the pancreas primary cancer of the liver cancer of the brain and chronic obstructive lung disease In 49 cases cancer of the pancreas was listed on the death certificate as cause of death Only 17.5 such deaths were expected TABLE 14 If we were to accept cause of death as listed on the death certificate to establish the observed number of deaths for this disease we would have to conclude that cancer of the pancreas is significantly increased as a cause of death among asbestos insulation workers But this is not the case when all available material was reviewed it was found that only 23 deaths compared with the 49 so categorized on the death certificate were due to cancer of the pancreas Four were the result of metastatic lung cancer 15 were found on review of histological material to be cases of peritoneal mesothelioma and 5 were best categor- ized as abdominal carcinoma primary site established Two were due to cancer of the colon This is not to say that we have established that there is no increased incidence of cancer of the pancreas amone asbestos workers it os possible there is some limited increase and we are cognizant of 15g uncertabies uncertarabunicertearas bies merent the Selikoff et al Mortality of Insulation Workers computation of expected rates for cancer of the pancreas since it may well be that some of the cases so categorized in the general population from which the expected rates were derived might really be instances of lung cancer colon cancer and even perhaps peritoneal mesothelioma Since these deaths in the general population have not been investigated to verify death certificate cause of death it is not possible to know whether such inaccuracy exists nor its degree Asbestosis was another example where categorization by death certificate would be misleading since only 78 deaths of this disease were so categorized compared with 168 after review A variety of other diagnoses were offered in the discrepant cases primarily those of chronic obstructive lung disease or other noninfectious respiratory disease acute infections and in two cases cancer of the lung It was of interest that in 16 of the 97 cases called asbestosis after review but in which asbestosis was not listed as the underlying cause of death it was mentioned on the death certificate under the rubric of other significant conditions In 129 other cases asbestosis was again mentioned on the death certificate but not as underlying cause of death Altogether asbestosis was mentioned in 230 of the 2271 death certificates In 7 cases asbestosis so categorized by death certificate designation was reassigned to other categories after review with death found due to lung cancer in 5 peritoneal mesothelioma in one and myocardial infarction in another Accuracy of diagnosis of mesothelioma and its being recorded on death certiticates is a special problem First there are the difficulties and subtleties of pathological diagnosis of particular importance when cases of this neoplasm are seen throughout the United States and Canada by pathologists with varied experience Sometimes there is the added difliculty of extending the pathological diagnosis to the death certificate not infrequently completed by a physician who may or may not have been the regular medical attendant and fully cognizant of pathological findings to this could be added the problem occasioned by the fact that the death certificate must often be completed before there has been full consideration of postmortem findings When these differ with the death certificate diagnosis an amended certificate is expected to be filed In our experience this is rarely done When to these are added the administrative uncertainties and insecurities of classification it is not surprising that only about quarter of the deaths of mesothelioma in this series were correctly recorded on death certificates as pleural or peritoneal although 104 of the 175 cases were recorded as mesothelioma even if not with full details We are presently analyzing the 175 deaths of pleural and peritoneal mesothelioma and the results will be reported In 108 of the 112 cases of peritoneal mesothelioma surgical and pathological material was submitted to us for review and this was the case as well as 61 of the 63 pleural mesotheliomas 96.5 and 96.8 The association of pleural and peritoneal mesothelioma with prior asbestos exposure is so striking that it is not surprising that overdiagnosis might now sometimes occur We found such to be the case in this study In 8 cases in which mesothelioma was recorded as underlying cause of death on the death certificate review of the histological material showed the diagnosis to be other than mesothelioma cancer of the lung in 5 cases metastatic carcinoma in 1 and Wegener's granulomatosis involving the pleura in another In the eighth case pleural mesothelioma was present but was not the cause of death which was better attributed to concurrent cancer of the stomach Where mesothelioma appeared as the diagnosis on the death certificate depending upon the exact phrasing used this might be coded in the eighth revision of the International List in categories 158.9 malignant neoplasm of peritoneum 163 0 malignant neoplasm of pleura 197.0 secondary malignant neoplasm of lung 195.0 malignant neoplasm of abdomen 198.9 secondary inalignant neoplasm specified as F: ts i t | , i , bE 114 Annals New York Academy of Sciences Cota secondary 199.0 multiple malignant neoplasm carcinomatosis disseminated cancer 199.1 malignant neoplasm without specification of site and not infre- e quently 228 benign neoplasm of other and unspecified organs and tissues There is at the moment no reliable way to extract the numbers of pleural and peritoneal a $0 let mesotheliomas from death certificate data categorized and recorded by health statistics agencies in the past using the several revisions of the International Classification of causes of death be degree sewn We might add that overall pathologists diagnoses were much more accurate than Piees death certificate characterization of causes of death would lead one to believe This again bespeaks a high of competence on the part of pathologists in the United ts States and Canada we are aware of course that diagnostic suspicion be th increased in those instances in which it is known that asbestos may exposure had occurred oe as with individuals among whom occupational history indicated such exposure this could perhaps have accounted for some of the diagnosis However this might be it is clear that a problem exists in translating the information obtained in pathological study to the death certificate diagnosis sell as a problem of subsequent coding of the stated cause of death Sn ero CONCLUSIONS re . a Asbestos insulation workers in the United States and Canada suffer an extraordi- CAT nary increased risk of death of cancer and asbestosis associated with their employ- OS ment This includes increases in death of lung cancer pleural mesothelioma peritoneal mesothelioma cancer of the esophagus colon and rectum cancer of the larynx pharynx kidney and perhaps stomach Some increases were seen in cancer of several other sites as well but data are inadequate at this time to permit characterization of their significance although attention is called to such wider increase Little increase in cancer deaths nor of asbestosis was observed in less than 15 19 years from onset of exposure In general the period of latency between onset of exposure and death was 2 3 4 or more decades Large increases in lung cancer occurred at 15- years from onset while pleural and peritoneal mesothelioma showed their greatest incidence somewhat later Under the conditions of exposure which obtained the period of clinical latency for asbestosis was also prolonged and in many cases was 30-40 years or more from onset of employment It would appear that in studies of the effects of such asbestos exposure it would be advantageous to analyze the experience of exposed individuals in duration exposure categories with particular reference to durations of more than 30 years If this is not done the risk is run of obscuring the neoplastic effects of asbestos exposure by the mingling of later deaths with those which may have occurred much earlier and which would be much less likely to have been influenced by asbestos exposure In the same way studies should include whenever possible the opportunity for observation of the mortality experience of the individuals at risk at least 30-35 and preferably 40 or more from onset of their exposure Again unless this is possible only the years limited effects will be identified and the full import of the exposures may notvebreyappreciaetaerdly Our experiences demonstrate the advantages of review of all available information concerning the circumstances associated with the deaths that occur Depending entirely upon death certificate diagnosis can lead to erroneous reports of causes of death a problem that can be mitigated by characterizing causes of death according to the best available information Using this approach we found that the increased incidence of cancer of the pancreas among astrest^s insulation indicated by death certificate diagnosis did not really exist and that apparent workers many ; neer sed tich any yze with kis ater such .dies lity cars arly d yon Ling of 200 rent ers Selikoff et al Mortality of Insulation Workers 115 designated were due to other causes The same was found for primary cancer of the liver and cancer of the brain both of which would have been considered of increased incidence using solely death certificate diagnosis but were not so established established following review of histological material This of course could well be anticipated with exposures to agents which increase the risk of neoplasms known to metastasize to these sites bronchogenic carcinoma gastrointestinal cancer Our experiences do not indicate that the addition of amosite asbestos exposure during and after World War I to the chrysotile asbestos exposure which existed before then and which continued demonstrably altered the nature of the asbestos- induced diseases which resulted nor their extent Further limited experiences suggest that asbestos insulation employment begun 1943-1962 carried the same type of term risk as that begun before that time We have no information concerning the nature or extent of risk among insulation workers whose employment began after 1963 ACKNOWLEDGMENTS os We are grateful for the extraordinarily valuable assistance of Ms. Janet S. Kaffenburgh and Ms. Frances Perez in the tracing and acquisition of material concerning the insulation workers in these cohorts Clearly the completeness of the ea prolonged serial observations could not have been accomplished without their dedicated and skillful help At the same time the leaders of the asbestos workers union equally share our gratitude Mr. Andrew T. Haas and Mr. William G. Bernard International President and International Secretary of the union Mr. Roy J. Stein- furth coordinator of the Insulators Health Hazard Program and the many union officers throughout the United States and Canada whose dedication and concern have permeated their work with us Special mention should be made of officials of the New York Jersey metropolitan locals of the union Mr. Jack Novak Mr. Harry Ahrens Mr. Terence McConnell Mr. Jerome Market Mr. Thomas Viscovich Mr. William D. Fitzgerald Mr. James Grogan Mr. James F. Dwyer Jr. and Mr. Howard Barnett Our warm thanks are due too to the staff of the Department of Epidemiology and Statistics of the American Cancer Society including Mr. David A. Newman Mr. Ashley Bodden Mr. Edwin Silverberg Ms. Marie Corbo who have with competence and dedication assisted in the extensive processing and computation of the statistical data that were obtained As so often nowadays this epidemiological study could not have been completed without the integrated cooperation of many Equally warm and strongly heid gratitude is due to our colleagues Dr. Jacob Churg Dr. Yasunosuke Suzuki and Dr. Milton Kannerstein for their help in reviewing the many anatomical and histological specimens that were made available to us Their skills knowledge and competence form a qualitative bedrock for the study Equally we are appreciative of the generous help given to us by clinicians pathologists medical examiners and others in medical facilities in all parts of the United States and Canada providing much pleasure and ity of medical and detailed information records roentgenograms We obtained as satisfaction from our experiences with the kindliness and generosscientific colleagues as with the observations these enabled us to make These acknowledgements would be sadly incomplete if they did not include our appreciation for the many at the day help assisted the rest amount of information inherent Environmental Sciences Laboratory whose whose patient of us and assured the collection of the very large in our data warm thanks are extended to Selma Annals New York Academy ofSciences Annenberg Richard Ashley Doris Fleisher Rupert Fuller Judith Marmor Maria Martinez Diane Monahan Vera Reitman Julia Roberts Albert Sidney Sibel Their work was the warp warp and woooff the fabric of the invReosdtriiggatuieozn and REFERENCES SELIKOFE J. ChurG & E. C. Hammond JAMA 188 22-26 1964. Asbestos exposure and neoplasia SELIKOFF J. C. HAMMOND & H. Seidman 1973. Cancer risk of insulation the United States In Biological Effects of Asbestos P. Bogovski et al Eds 20w9o-rk2e1r6s JARC Sc Pub No. Lyons France Satikon | J. Churg & C. Hammond 1965. The occurrence of asbestosis insulation workers in the United States Ann N.Y. Acad Sci 13251 112-120 FROST J. Grorg & L. Moiler Moiler 1966. Asbestosis with pleural calcification insulation workers Danish Med Bull 3471 202 -204 among among NICHOLSON W. J. 1976. Case Study Sci 271 152-169 1 Asbestos TLV approach Ann N.Y. Acad SELIKOFF 1. J. C. HAMMOND & J. Churg neoplasia JAMA 204 106 112 1968. Asbestos exposure smoking and _ 7 Fletcher C. M. 1978. Terminology in chronic obstructive Comm Health 32 281-288 lung diseases J. Epidemiai HAMMOND E. C. J. SFLIKOFF & H. SEIDMAN SEIDMAN 1979. Asbestos smoking and death rates Ann N.Y. Acad Sci This volume exposure cigarette British Occupational Hygiene Society Hygiene standards for chrysotile asbestos 1968. Ann Occup Hyg 47 69 dust SELIKOFF L. 1964. ^ n Discussion Ann N.Y. Acad Sci 132. : 596 AUERBACH ) A. CONSTON C. HAMMOND L. GARFINKEL & V. press Parks 1979. In Berg J. W. D. SCHOTTENFELD 1977. Multiple primary cancers at 1949-1962 Cancer 40 F801-1005 F801-1005 SELIKOFF J. 1965. The occurrence of pleural calcification among workers Ann N.Y. Acad Sci 132/1 351-367 Memorial Hospital asbestos insulation SPGKOFF SPGKOFF J. Cancer risk ofasbestos exposure 1978. In Origins of Human Cancer H. H. Hiatt J. D. Watson and J. A. Winston Eds 1965-1984 Cold Spring Harbor New York PERCY C. & A. DOLMAN 1978. Comparison of the coding of death certificates related to cancer in seven countries Publ Hlth Reports 93 335 350 ENTERLINE P. P. DE Coufle & V. HENDERSON 1973. Respiratory cancer in relation to occupational exposures among retired asbestos workers Brit J. Industr Med 30 162 166 COCHRANE C. & L. WEbster A. Med J. 54 279 281 1978. Mesothelioma in relation to asbestos fibre exposure es ver y va whe chants na-hen ux. cblent. alr notin biel ee + 20