Document reX0ZXaj4OkNxrNvXXLVDOy2a

HOW TO USE THE8E SEPARATORS Use one page fo r each sep aratio n * Select appropriate tab , add fu rth e r id en tificatio n i f d e sire d , and cover it with scotch tape. Cut o f f and d isc a rd a ll tab s except the one covered by tap e. TABBED SEPARATOR SHEET Fora MEW-69B Mortality Experiences Among Talc Workers: A Follow-up Study M. Kleinfeid, M.D., J. Messite, M.D. and M. H. Zaki, M.D. ---- . ------------------ In an earlier study of talc workers who had 15 or more years of exposure to commercial talc dust, the authors found that the proportional mortality from carcinoma of the lung and pleura among these workers was four times that of the general population. However, the significant increase in incidence of malignancy appeared in the older talc workers, namely, the 60 to 79, rather than in the 40 to 59 year age group.1This observation in the talc workers was at variance with those found in a group or asbestos insuiators who had the same duration of exposure covering a similar time period.2 The asbestos insulators showed an increased incidence of mor tality from lung cancer in both age categories. The incidence ot carcinoma of the gastrointestinal tract and peritoneum among the talc workers was not significantly different from that of the general population, whereas among the asbestos insulators the incidence of gastrointestinal m alignancy was significantly higher. The authors postulated that the earlier occurrence of malignancies among the asbestos in sulators was due to two factors. The first was the relatively greater carcinogenicity of the chrysotile asbestos as compared to commercial talc. The seqond ractor was the exposure of the insulators to greater quantities of chrysotile asbestos as com pared to the talc wo.kers who were ex posed to lesser quantities of talc dust which was admixed with appreciable amounts of tremolite and anthophyllite from the New York $Ute DefMrtment ot LdOor Division of Industrial and the Stjfp Univer sBitryookolyfn,NNewY York. Oowostate Medical Center. Reprint requests to Dr Kleinfeid. 400 Ocean Park way. Brooklyn, NY 11^18 asbestos. The earlier,sXtudy1 also showed an increased incidence of deaths due to taic pneumoconiosis and/or its com plications. The present study was designed to bring the mortality data among the talc workers up to date and to provide additional information not reported in the earlier study. Materials and Methods All the talc workers employed in 1940 who had accumulated 15 or more years of exposure to commercial talc dust as well as those who achieved a minimum of 15 years of such exposure between 1940 and 1969 were included in the study. The group totaled 260 workers and it is believed that the overafl number constituted the total work force iri the worker population under study. Source of D ata.-- The data were ob tained from a number of sources. Plant records were examined and the work history of each individual was detailed to include changes of job and specific years of employment. Death certificates were studied in all instances where they were available. The records of the physicians w ho had attended the workers privately were reviewed. Sub stantial medical information on the majority of the workers was available in the Division's files which were used as an additional source of data. Hospital records, including autopsy reports and histological specimens, were examined wherever available. Autopsy or biopsy records were obtained in 38 of the 108 deaths. Statistical Analysis.-- The causes of death included the following- malignan cies, cardiac diseases other than cor pulmonale, pneumoconiosis and its complications; accidents or suicides. Journal of Occupational Medicine/Vol 16, No 5/May 1974 and all other causes. In vie< limitations of the available date of the mortality experience b years of exposure was not feasil alternate, a comparison was m; observed proportional morta from the specific causes wit! peeled rates among similar p groups and was found satisfac descriptive study of this nai proportions of observed moi tributed to cancer of the lung a and of the gastrointestinal t peritoneum and cardiac disea compared to the expected r due to the above causes in th age groups. The expected mo the total group represents the p of deaths among white mei United States due to the specil in the year 1955. This particular chosen as standard because median year of death among deaths. For each of the 5-yea the median years, namely, 19 1952^1957 and 1962 were sele ferences between observed peered frequencies were te significance using the normal large numbers and the Fishe probability test for small frequ Findings Total D e a th s.-- There w deaths in the group of 260 talc The causes of death in the categories are shown in Tal distribution of the deaths acci age group appears m Table average age at death of the workers was 60 3 years, with a 38 to 84 years. Table 3 shows death and the number of deal! each 5-year period from 1940 ' Table l . - ~ c l f ^ o ! Death in 108 Talc Workers During Period ol 1940 to 1969 Cause d Deal* Hs. k'al'gnancies lung and Pleura Gastrointestinal and peritoneal Ail Gtnei Cardiac Deaths (other than cor pulmonale) Pneumoconiosis and Complications Accidents or Suicides All Other Causes 25 13 9 3 3029 8 J6 . TctJ 10 S 23.1 12.0 8.3 28 2?a 26.9 7.4 14 8 100.0 M alignancies.-- Deaths from cancer of the respiratory- tract and gastroin testinal tract and observed and expected proportional mortality rates are shown in Table 2. Tweh'e of the 13 malignancies of the lung and pleura were carcinomas of the lung and 1 was a fibrosarcoma of the pleura. Of the 9 malignancies of the gastrointestinal tract and peritoneum, 3 were cancers of the stomach; 2 were cancers of the liver, 1 of which was a primary hepatoma of the liver and the other a metastasis from a gastrointestinal malignancy; 1 was a cancer of the colon; 2 were cancers of the pancreas; and 1 was a peritoneal mesothelioma. The 3 malignancies involving other sites in cluded 1 retroperitoneal reticulum cell g |c o m a , 1 chronic lympliatic leukemia 1 Hodgkins' disease The observed deaths and expected proportional mor tality from cancer of the lung and pleura and of the gastrointestinal tract and peritoneum during the 5-year periods ex tending from 1940 to 1% 9 are shown in Table 4. Cardiac D eaths.-- O f the 30 cardiac deaths, excluding cor pulmonale, 22 had coronary artery disease, 5 had hyper tensive heart disease and 3 had rheumatic heart disease. Table 2 shows the deaths and proportional mortality' from cardiac disease related to specific .age groups and Table 5 gives a break down of the number of deaths from car diac disease during the specified 5-year periods. Pn eum o con io sis and its C o m plications.-- There were 29 deaths in this group. Twenty of the 29 were due to cor pulmonale, 5 to advanced tuber culosis and 4 to bronchopneumonia. The lapsed time from the first talc ex- Age Group < 40 40-59 60-79 80-84 Total Total Deaths 3 47 54 4 tot Tatila 2. -- Deaths and Proportional Mortality from Carcinomas of the Respiratory Tract, of the Gastrointestinal Tract, and From Cardiac Diseases Among.Tale Workers by Age, 1340-1969 - Deaths and Proportional Mortality From Respira tory Cancers (%) Deatns and Proportional Mortality From Gastro intestinal Cancers (%) Deaths and Proportional Mortality from Ca'dUc Diseases <%> ho Observed Eipected Ha Observed Expected No Observed Ejected 00 1.6 0 0 23 3 33 3 21.1 4 85 .5 2 3 6.4 5.7 11 24.4 44.2 9 16.6 u 3.6 4 7.4 n 17 31.5 47.8 00 11 1 25.0 5.3 1 25.0 47,1 13 12.0 3.7 t 7A 63 30 27.8 4SI ' m ' Tibie 3. -- Causes of Death in 108 Talc Workers* During the Period 1940-1969 Cjv Vaii 1940-44 1945-49 1950-54 1355-59 Malignances lung and Pleura Ston-ath Liver Colon Pancreas Peritoneum Other Malignando Cardiac Diseases Pneumoconiosis and Complications Acndents and Suiades Gtfters To*it 2 --1 1-- - -- ' -- ---- ---- ---- 3. 6 24 11 --3 7 17 1 -- _ -1 -- -- 2 __ 2 1 1 S 5 1 1 -- -- 1 6 8 2 1 25 * who had at least 15 or more years of exposure to talc dust - 1960-64 3 -- -- , -- I -- -- 8 9 2 5 28 1965-69 2 1 -- 1 -- 1 7 4 1 6 23 - Total 13 3 2 1 1 l 3 30 ' 29 8 (6 108 ' : Mortality Experiences Among Talc Workers/Kleinfeld, Messile and Zaki 194044 19(549 1950-54 1955 53 1960 64 1965-69 Total Table A^DTeaths an..d....E..r.p..e..c..t.e..d.....M...o..r.t..a.l.i.t..y....f.r.o. m Cancer of the lung a ij^ e u ra and el the Gastrointestinal Trad and Pen! ineum Amonj Talc Workers 1940-1969 ' lonf and Fleur* ttttrointtttinj) Tract and Peritoneum Deaths Proportional Mortality c%> Obsenred Expected Deaths Proportional Mortality (%) Observed Expected 00 2.0 1 14.3 7.8 2 11.1 3.1 1 59 7X 1 12.5 a 1 12.5 7.1 5 20 0 5.7 3 12.0 67 3 10.7 6.7 1 -- 3.6 6.3 2 6.7 7.7 2 9.5 6.1 13 9 .- i t \ posure to death in this group averaged 30.9 years, with a range of 15 to 46 years. All 29 had their initial exposures prior to 1945 at which time more ef fective engineering controls, including wet drilling in the talc mines, were in troduced. AH O ther C a u se s.-- In addition to 8 accidents and suicides, there were 16 additional deaths in this category. Three were due to cerebrovascular accidents, 4 to pneumonia, and the remaining 9 to one of the following causes: bleeding CJU U Utrildf UiCcM, S u a O g u f a i O C i r i g u . u a ! hernia, perforated diverticulum with peritonitis, acute glomerulonephritis, mesenteric arterial occlusion, intestinal obstruction, uremia, and gunshot wounds Environm ental Exposure. -- En vironmental exposure data was available in 97 of the 108 death cases The mean duration of exposure for this group was 24.1 years, with a range of 15 to 47 years. The dust exposure was predominantly to talc, tremolite, anthophyllite, carbonate dusts and a small amount of free silica. Comparative dust counts at the talc mines and mills prior to 1945 and between 1946 and I969 are shown in Table 6. Table 7 shows the deaths from respiratory and gastroin testinal malignancy, cardiac disease and from all causes among the talc workers by years of exposure to commercial talc dust. Comments M alignancies.-- The data on car cinoma of the lung and pleura show the overall proportional mortality to be ap proximately four times that expected. Consistent with our previous ob servation1 a significant increase appears to occur in the age group of 60 to 79 years rather than in the 40 to 59 year age group. As has been mentioned, this find ing among taic workers is at variance with what the authors have observed among asbestos insulators where the ob served values in both the 40 to 59 and 60 to 79 year age group were significant ly different from the expected values. Kiviluoto and Meurmani also reported the occurrence of lung cancer among younger anthophvliite miners (45-54 year age group) who had more than 10 years of exposure, with a mean of ap proximately 20 veers, to pure anthophyllite asbestos. Two explanations are offered. One is that the mixed dust to which the talc workers were exposed, namely, talc, tremolite and anthophyllite, is less carcinogenic than chrysotile dust to which the asbestos insulators were ex posed. The second is that the talc workers were exposed to a lesser con centration of dust compared to the asbestos Insulators and anthophyllite miners. One or both of these factors may account for the difference in the mor tality experience of the talc and asbestos workers groups. In the absence of adequate smoking data, one cannot assess the role played by smoking in ac counting for the differences m the occcre n ce of malignancies. When carcinoma of the lung and pleura are related to each of the six 5year periods, as shown In Table 4, It is noteworthy that the observed propor tional mortality from carcinoma of the lung was approximately four times as much as the expected mortality during the years 1945 to 1959 and dropped to I approach the expected mortality In I960- 1 64 and 1965-69. The differences between 1 the observed and exoected. mortality | rates w ere significant In 1950-54 (P<0.01) and insignificant in 1960-64 | and 1965-69 (P>0.05). The improved f mortality experience between 1960 and | 1969 in the case of lung and pleural can- | cers is particularly pertinent since en- vironmental controls have resulted in an 1 appreciable reduction in the dust counts | in the mines and mills, although the fiber | counts still remain high (Table 6). This | finding Indicates that the present threshold limit tor tremolite and an thophyllite needs rvaluation. With regard to cancer ot the gastroin- g testlnal tract and peritoneum among the | 194044 194549 1950-54 1955 59 1960 64 1965 69 To T*bl 5. -- Deaths and Expected Mortality From Cardiac Disease Among Talc Workers 1940-1969 Deaths Proportional Mortality {%) Observed Expected 3 42.8 37.4 6 35.3 41.6 0 0 46.0 6 24.0 465 8 216 46.6 7 304 45.5 u Journal of Occupational Modiclne/Vol. 16, No. 5/May 1974 347 Table S. -- Comparative Dust and fiber Counts it the Various Talc Mining and Milling Operations P ro 1915 through 1969 Dud Counts* tn 1945 Aire.' * Med.** 1946-1965 A * ." Mod." 1965 1969 Ave." Med." Drilling SIS <13 MoeVjng 120 30 fn IM I Crushing 180 69 Screening 63 61 Milling 92 75 ' Garnering & Separating Pulverizing 278 -- 70 -- ' Bagging 151 129 RR S Truck Loading -- -- 8l<w Rxjq* ' * 122? 1196 Open Chutes* * 125 83 5 5 1948-1965 42 37 25 3 5 13 37 20 27 27 28 28 27 23 73 63 Dust courts m rnppcf. fiber counts m no fibers/ml. * 5u in length * "' Ave averse, Med. median ' "' Operation discontinued after 1948 ' 19 9 28 __ 40 -- -- 29 43 '-V 19 9 20 _ 24 __ 25 20 1972 Dust Counts' Fiber Counts* Ave." 7 3 35 __ 7 13 __ 27 36 Ked." 7 3 _15 7 9 __ 27 28 3 2 62 . 25 27 --. 47 24 -' -* ' - . - ... - talc workers, we did not find any significant difference between the ob served arid expected values tn the overci! and specific age groups studied Nor did Kiviluoto and Meurman find an increased incidence of gastrointestinal cancer among the anthophyllite workers they studied 3 These findings differ from those observed in asbestos insulators where a significant increase in the ob served incidence of gastrointestinal malignancy was found in the overall and specific age groups studied 1 Our find ings among asbestos insulators were similar to those reported by Selikoff, Hammond and Churg 4 Deaths Due to Pneum oconiosis and its C o m plicatio n s.-- A previous study has shown that cor pulmonale is a major complication of talc - pneumoconiosis and is a major cause of death among talc workers 1 The findings in this study confirm the previous report However, as shown m Table t the percentase of deaths due to pneumoconiosis and its complications has decreased by more than 50% in the last 5-year period studied (1965-69) as compared to the preceding period The number of deaths probably retlects the greater exposures which occurred in the earlier years of employment. A longer interval must elapse, however, before the effect of controls on the in cid en ce of pneumoconiosis can be appraised more definitively in the plant studied In another study of a different plant5 processing a similar mixture of talc, tremolite and anthophyllite but wherein controls were installed at the inception of operations in 1948, only one of 39 workers had a chest roentgenogram con sistent with pneumoconiosis. The mean exposure of the 39 workers was 16.2 years with a range of 11 to 22 years. The worker whose chest roentgenogram was consistent with pneumoconiosis was a 75-year old man who had a non productive cough, a Grade 1 dyspnea and who worked as a janitor for 11 years The low incidence of pneumoconiosis was found despite the presence of relatively high fiber and dust counts The fiber counts exceeded by 2 to 6 times the present threshold limit value of 5 fibers/ml with a length greater than 5 microns. In terms of time weighted averages, M urphy and associates* found no asbestosis among workers exposed less than 60 mppcf- Cum 1 Dotti Malignancy of the Respiratory Tract Mahgnency of the Gastrointestinal Tract Cardiac Oisease AH Causes 48 Table 7 .-- Deaths From Respiratory and Gastrointestinal Malignancy, Cardiac Disease and from All Causes Among Talc Workers by Tears of Eiposure to Tate Dust . Tiptauri in Tars 15-19 20-24 25-28 30-34 35-38 40+ 37 1 2 1 1 12 9 8 4 22 24 35 15 12 6 J 1 1 5 Unknown i ! 4 II Tots! 1 9 30 108 Mortality Experiences Among Talc Workers/Kleinfeld, Messiti and Zaki , , >we in ship ojnsifuction In the study of the having con'rols since the star^ H f operations, it was found that an ap preciable number of workers exceeded the 60 mppcf-years. but did not show any evidence of pneumoconiosis as determined by the criteria of Murphy and associates. The authors' concluded from the study of the plant having con trols from the outset of operations that tremotite and anthophyllite were less fibrogenic than chrysotile or amosite at comparable dust exposures Deaths from Cardiac Disease. -- Rather surprising was the observation that the observed proportional mortality from cardiac disease w as lower than the expected mortality m all 5-year periods except the first, namely, 1940-1944 (Table 5). No valid con clusion could be drawn regaiding this period since the authors could find records of only 3 deaths in the period 1940-1944. H o w e v e r, it seem s reasonable to state on the basis of the remaining data that the overall observed proportional mortality from cardiac disease among talc workers was lower than the expected mortality. The decreased mortality from cardiac disease among talc workers cannot be attributed to a predispos11ion to ung cancer which generally results in the death of these workers at earlier ages before they might be expected to succumb to cardiac disease. As Table 2 demonstrates, the decreased proportional mortality from cardiac disease is present in both the 40 to 59 as well as the 60 to 79 year age group are needed to validate Ibis ex- group If malignancy of the lung was a ^^alanation. With regard to malignancy of factor, one would have expected a dif gastrointestinal tract, the deaths were ference In incidence between these two distributed over all periods'of exposure age groups Deaths in the age group un The small number of deaths does not der 40 and 60 to 84 are too few to lend itself to provide any conclusion warrant any comments with regard to regarding the risk of developing cardiac disease. The true explanation is malignancy in the gastrointestinal tract open to coniecture. The rural en and years of exposure. With regard to vironment in which the talc workers deaths from cardiac disease, Tables 5 lived, as welt as the possibility that they and 7, there does not seem to be any dif smoked less, may account for the lower ference regarding the years of exposure mortality due to cardiac disease as com and the exposure pattern in the total pared to the national rate. group. Correlation of Malignancy with Age and Years of Exposure.-- The data shown in Table 7 indicate that the maiority of the malignancies of the respiratory tract occurred in the workers exposed 15 to 24 years. During this period 10 of the total oN 13 died from malignancy of the respiratory tract. In this group the elapsed time from onset of exposure to death was similar to the duration of exposure. The finding suggests that the carcinogenic effect of the commercial talc dust is manifested mainly after exposure of 15 to 24 years and that very prolonged exposure, 25 years plus, does not appear to carry with it a significantly increased risk for cancer production One plausible explanation Is that a more susceptible giCup will develop cancer between 15 and 24 years and that after 24 years there is a group vvhich is relatively less susceptible to cancer production in spite of added years of exposure. However, co n firmative findings in the study of a larger References V Klemfeld M. M essite I, Koovm an O and Zaki M: Mortality among talc miners and millers in t.e w York State. Arch Environ Hith 14 663-67, 1967. 2. Klemfeld M. M essite I and Koovm an O : Mortality experience in a grouo of asbestos workers Arch En'iron Hlth 15:177-80. 1967. 3. Kiviluoto R and M eurm an L. Results of asbestos exposure in Finland, pp. 180-186. In H. A. Shapiro. Ed.. P n eu m o co n io sis. Proceedings of the International Conference, lohannesburg. 1969 Cape Tow n: Oxford University Press. 1970. 4. Selikoff II. H am m ond EC and Churg |: Mortality experiences of asbestos insulation w orkers, 1943-1968. pp 130-186. In H. A. Shapiro, Ed . Pneum oconiosis Proceedings of the International Conference, lohannesburg. 1969. Cape Town: Oxford University Press, 1970. ' 5. Kleim eio M, M essite I and Langer Am - A study of workers exposed to asbestiform m inerals in com m ercial talc m anufacture En viron Res 6 132-243, 1973. 6. Murphy R IM . It.. Ferris BG , Burgess W A , et a l :. Effects -of low concentrations of asbestos. New Engl I M ed 285.1271-1278, 1971. . urnal of Occupational Medicine/Vol. 16, No. 5/May 1974 349