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EXHIEIT V / best available copy J Paper Presented at the Metal and Nonmetallic Mine Health and 8aety Symposium on Talc Dust Hazards Held in Washington, D.C. on Tuesday, May 8, 1973 By Morris Kleinfeld, M.D., Formerly Director of the Division of Industrial Hygiene, New York State / i My former colleagues In the Division of Industrial Hygiene of Mew York State and I have had the opportunity to conduct numerous studies of talc workers in New York State, including, clinical, physiological, radiological and environmental observations^ In addition, we have also studied the mortality experiences among workers in talc mining and willing In most Instances, we have had the invaluable opportunity to correlate the clinical with the environmental data In general, we have found that sustained inhalation of significant amounts of commercial talc dust over an extended period of time, or where there was a significant lapsed time from initial exposure, can produce a synptomatic form of pneumoconiosis The commercial talc to which the talc workers were exposed contained not only the mineral talc, but also other silicates Vtrt' -- - - . ... . such as serpentine, tremolite, anthophylllte and other ingredients, predominantly carbonates* Moreover, free silica was often present in the dust in variable amounts', usually not averaging more than 3 percent Specifically with regard to our mortality experiences among talc workers, we found in an earlier study of talc workers (miners and millers) who had 15 or more years of exposure to talc dust 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, those in the 60 to 79 year age group, rather than in the 40 to 59 (2) year age group This observation in the talc workers was at variance with those found in a group of asbestos insulators who had the same (3) duration of exposure covering a similar time period The asbestos insulators showed an Increased incidence of mortality from lung cancer in both age categories The incidence of carcinoma of the gastrointestinal tract and peritoneum among talc workers was not significantly different  Kb 2 * *% .. /' from that of the general population, whereat among the asbestos insulator* the incidence of gastrointestinal malignancy was significantly higher than that of the general population* We postulated that the earlier occurrence of malignancies among the asbestos insulators was due to two factors* The first was the relatively greater carcinogenicity of the chrysotlle asbestos as compared to commercial talc* The second factor was the exposure of the Insulators to greater quantities of chrysotile asbestos as compared to the talc workers who were exposed to lesser quantities of commercial talc dust which was admixed with appreciable amounts of tremolito and anthophyllite (2l asbestos* Our observations favored the first factor* The earlier studyv * also showed an increased incidence of deaths due to talc pneumoconiosis and/or its complications* A follow-up study was made to bring our mortality data among the talc workers up to date and to provide additional information not reported in the earlier study* The pertinent data is indicated below* All the talc workers employed in 1940 who had accumulated 15 or more years of exposure to comnereial talc dust as well as those who achieved a minimum of 15 years of such exposure between 1940 and 1969 were included in the follow-up study* The group totaled 260 workers and it is believed that the overall number constltilted the total work force in the worker population under study* The data were obtained 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 who had attended the workers privately were reviewed* Substantial medical information on the majority of the workers was available in the files of the Division of Industrial Hygiene and was used as an additional source of ITC" *-K*"* r *'~ ~n ^ / data* Hospital records, including autopsy reports end histological specimens, were examined wherever available Autopsy or biopsy records were obtained in 38 of the 108 deaths v ,r A comparison was made of the observed proportional mortality rates from the specific causes with the expected rates among similar population groups and was found satisfactory for a descriptive study of this nature The proportions of observed mortality attributed to cancer of the lung and pleura ffid,ofvthe gastrointestinal tract and peritoneum and cardiac diseases were Compared to the expected mortalities due to the above causes in the various .groups* The expected mortality for the total group represents the pro portion, of deaths among white men in the United States due to the specific causes in the year 1955 This particular year was chosen as standard because .was the median year of death among the 108 deaths For each of the 5-year periods, the median years, namely, 1942, 1947, 1952, 1957 and 1962 were selected* ........ . . . . . . ,, .,rIn the group of 260 talc workers studied, there were 108 deaths There T 1 v'~ - - '- - - -- - . .... , were a total of 25 deaths from malignancies Of these 25 deaths, 13 were due .to lung and pleural malignancies) 9 were due to gastrointestinal and peritoneal mlignancies and 3 were due to other malignancies Thirty deaths resulted from cardiac disease, other than cor pulmonale, and 29 deaths were attributable to .pneumoconiosis and its complications Accidents and suicides accounted for 8 deaths and there were 16 deaths due to other causes (Table 1) The average .9# at death of the 108 talc workers was 60*3 years, with a range of 38 to 84 years Environmental exposure data was available in 97 of the 108 death cases The mean duration of exposure for this group was 241 years, with a range of 15 to 47 years The dust exposure was predominantly to talc, tremolite, anthopftyllite, carbonate dusts and a small amount of free silica Cooperative dust counts at the talc mines and mills prior to 1945 and betwten 1946 and 1969 were obtained (Table 6 )* .ere With:regard to the deaths due to malignancies, 12 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 stomachf 2 were cancere of the liver, 1 of which was a primary hepatoma of the liver and the other e metastasis from a gastrointestinal malignancy! 1 was a cancer of the colons 2 were cancers of the pancreasj and 1 was a peritoneal mesothelioma. The 3 malignancies involving other sites Included 1 retroperitoneal reticulum cell sarcoma, JcchTonic lymphatic leukemia and 1 Hodgkins* disease (Table 3). The overall proportional mortality of carcinoma of the lung and pleura was four times that expected. Consistent with our previous observation, a significant increase appeared to occur in the age group of 60 to 79 years rather than in th 40 to 59 year age group (Table 2). As I have already mentioned, this finding among talc workers was at variance with what we had observed among asbestos insulators where the observed values in both the 40 to 59 and 60 to 79 year age groups were significantly different fran the expected values. In the absence of adequate smoking data, one cannot assess the role played by smoking in accounting for the differences in the occurrence of malignancies. ; When carcinoma of the lung and pleura was related to each of the six 9-year periods, namely, from 1940 to 1969, it is inportant to note that the observed proportional mortality from carcinoma of the lung was approximately' four times as much as the expected mortality during the years 1946 to 1949 and dropped to approach the expected mortality In the years 1960 to 1964 and 1965 to 1969 (Table 4), The differences between the observed and expected mortality rates were significant in 1950-54 and insignificant in 1960-64 and , * $ '' . ,' /' f' 1965-69. The improved mortality experience between 1960 and 1969 and to date (1973) in the case of lung and pleural cancer it particularly pertinent V-, -- ** ' - alnce environmental controls have resulted in an appreciable reduction in the duet counts in the mine and mills* although the fiber counts still exceed cf thi i-*.-.-. I ' . the present threshold limit value for asbestos dust by approximately four to c: tr.c r 1. v r - . five times (Table 6 ) This finding indicates that the present threshold limit per; ter.'*- . : - r value of 5 fibers/ml with a fiber length greater than 5 microns for fibrous vv.i;... :. : .. _ talc* including tremolite and anthophyllite, is basically adequate c a s c r c i n v . r.Lr............. ~ With regard to cancer of the gastrointestinal tract and peritoneum among the talc workers* we did not find any significant difference between the Wrjv;" r ;. observed and expected values in the overall and specific age groups studied (Table 2) and are consistent with findings reported by Kiviluoto and r.rrr.:(4) Iteurman . among anthophyllite workers These findings differ from those f.:-: c r ::v .. observed In asbestos insulators where a significant Increase in the observed Incidence of gastrointestinal malignancy was found in the overall and *- ( 2 ) specific age groups studied Our findings among asbestos insulators -' - : - (5 ) were similar to those reported by Sellkoff* Hammond and Churg ti. .itr. i.' . . '6 Of the 29 deaths due to pneumoconiosis and its complications* 20 were due to cor pulmonale* 5 to advanced tuberculosis and 4 to bronchopneumonia The lapsed time from the first coeroercial talc dust exposure 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 effective engineering l m. . . - - . . ' controls* including wet drilling in the talc mines* were introduced. The percentage of deaths due to pneumoconiosis and its complications has decreased by more than 50 percent in the last 5-year period studied* namely* 1965-69* as compared to the preceding period (Table 3) The number of deaths probably reflects the greater exposures which occurred In the earlier years of eqployment* A longer Interval must elapse, however, before the effect of controls on the incidence of pneumoconiosis can be appraised More definitively in the plant studied. It is noteworthy, however, that in another study of a different plant processing a similar mixture of talc, txemolite and anthophyllite, but wherein controls were installed at the inception of operations in 1948, only 1 of 39 workers had a chest roentgenogram consistent with pneumoconiosis* The mean exposure of the 39;workera was 16.2 years with a range of 11 to 22 years* The worker whose cheat roentgenogram was consistent with pneumoconiosis was a 75-year Old man who had a non-productive cough, a Grade 1 dyspnea and who worked a janitor for 11 years* The low incidence of pneumoconiosis was found despite the presence of relatively high fiber and dust counts in this (6) plant The fiber counts exceeded by two to six tines the present threshold limit value of 5 fibers/ml with a length greater than 5 microns* (7) In terms of time-weighted averages, Murphy and associates found no aabestosia among workers exposed less than 60 mppef-years to chrysotlle and amoslte in ship construction* In the study of the plant having controls since the start of o p e r a t i o n s ^ , it was found that an appreciable number of workers exceeded the 60 mppef-yeaxs, but did not show any evidence of pneumoconiosis as determined by the criteria of Murphy and associates. The findings from the study of the plant having controls from the onset of operations suggest that tremolite and anthophyllite are less fibrogenic than chrysotlle or amoslte at comparable dust exposures* Of the 30 cardiac deaths, excluding cor pulmonale, 22 had coronary artery disease, 5 had hypertensive heart disease and 3 had rheumatic heart disease* Rather surprising was the observation that the observed pro portional mortality from cardiac disease was lower than the expected * V- / mortality in all 5-year periods except the first* namely, 1940-1944 (Table 5)* It seen reasonable to state on the basis of the remaining data that the overail observed proportional mortality from cardiac disease among talc workers was lower than the expected mortality* The decreased mortality from tXC :' '-- '' ` `cardiac disease among talc workers cannot be attributed to a predisposition t o l u n g c a n c e r which generally results In the death of these workers at earlier ages before they might be expected to succumb to cardiac disease* Afc demonstrated* the decreased proportional mortality from cardiac disease wait present ih both the 40 to 59 as well as the 60 to 79 year age groups tTkble 2)* If malignancy of the lung was a factor* one would have expected a difference in incidence between these two age groups* The true explanation for the lower Incidence of cardiac disease is open to conjecture* The rural ^ _ \- . - ,, _ _. . environment in which the talc workers lived* as well as the possibility that thoy smoked less, may account for the lower mortality due to cardiac disease 4* compared to the national rate* <S` I trust that the information I have submitted this morning will provide the Bureau of Mines with essential data relating to the occupational hazards of exposure to talc* fibrous talc and tremolite dusts in order to evaluate the adequacy of the existing threshold limit values for pure talc and talc mixed with tremolite and anthophyllite* * . '' . / 1*. c c r i u c . i . - - Inference* ' cli: JUeinfeld, M., Messlte, J., Shapiro, J. And Svencicki, R.t Effect of wsri'.cTalc Dust Inhalation on Lung Function. Arch Environ Health 10 care i431-3?, 1965. v2* 2delnfeld, M., Messlte, J., Kooyman, 0. and 2aki, M. Mortality Among err] Talc Miners and Millers In Mew York State* Arch Environ Health 14 A: c 863-6?, 1967. vl* lelnfeld, M*, Messlte, J. and Rooyman, 0. s Mortality Experience in a (7 :7 Croup o Asbestos Workers. Arch Environ Health 15t 177-80, 1967. A - iRLviluoto, R. and Meurman, L. t Results of Asbestos Exposure In Finland, fer p;>. 180-188. IN H. A. Shapiro, Ed.i Pneumoconiosis. Proceedings of the cr.v:International Conference, Johannesburg, 1969. Cape Town Oxford th: University Press, 1970. 5 rSelikoff, I. J., Hammond, K. C. and Churg, J.i Mortality Experiences of Asbestos Insulation Workers, 1943-1968, pp. 180-186. 1H H. A. Shapiro, Ed.t PneuooconiosIs. Proceedings of the International Conference, c'i cJohannesburg, 1969. Cape Town Oxford University Press, 1970. 4 Klelnfeld, M., Messlte, J. and Langer, A. M. * A Study of Workers L i Exposed to Asbestifora Minerals in Connarcial Talc Manufacture. Environ Res. Accepted for Publication. 7. Murphy, R. L. M. Jr., Ferris, B. G., Burgess, W. A., et alt Effects of Low Concentrations of Asbestos. v Il I New Engl J Med 265 1271-1278, 1971. . t I-eier. ._ 1. F.lcinitli, ivesricc. Z. , Z Tele Dust Lnr.ais.ticr. or. Lur r lui-ctic:.. Arc T; L:.v.rc. - . :w .. 431-57, is;:. Xabl* 1 2. Q c liiftlc , J . , f-ccyr^ r., C Y ; ; -;__ _ Talc Minerr (Causes of Death, in 108 Talc Workers Daring Period of 1940 toi 1969 653-i?, 1 '. ' ' 3. Iv i c i r* c lc l. f wl "rc i . tc , J . c.r . ^ - - } Cause of Death Ho. ..V ... w. Malignancies . ve L. Dung and Pleura Castrointestinal and peritoneal > --- - All other malignancies ir.v: : . v . :.v .. . : Cardiac Deaths (other than cor pulmonale) V.v iv e ri ::- . ' - Pneumoconiosis and Complications t < -* - '" . ^^ Accidents or Suicides /-riiw All Other Causes . 1 '-. 23 * 3 .... . . 2 ..... 3 30 29 % : 16 . Total 108 1 23.1 12.0 8.3 ---- 2 .8 27.8 2C.S 7.4 14 8 100.0 IU c.ira cl;, /. % Tal*U 2 Deaths and Proportional Mortality Pros Carcinomas of the Respiratory Tract of the Gastrointestinal Tract, and From Cardiac Diseases Among Talc Workers by Age, 1940-1969 Age Group 40 40-59 60-79 80-84 Total Deaths Deaths and Proportional Mortality From Respiretory Cancers (% T ~ Ro Observed Expected 3 47 54 4' 0 4 9 0 0 8.5 16.6 0 1.6 5.2 3.6 1.1 Total 108 13 12.0 3.7 Deaths and Proportional Mortality From Gaatrointestinal Cancers WT Ro Observed Expected 00 3 6.4 4 7.4 1 25.0 2.5 5.7 ' 7.2 5.3 8 7.4 6.5 Deaths and Proportional Mortality From Cardiac Diseases T%T~ Ro Observed Expected 1 33.3 11 24.4 17 31.5 25.0 21.1 44.2 , 47.8 47,1 30 2.8 45.8 1m\ Table 3 Cause of Death In 108 Talo Workers* During the Period 1940-1969 t. I-IV. I** Cause of Death 1940-44 1945-49 1950-54 Malignancies Lung and Pleura m 2 1 Stomach m1 - Liver 1 m- Colon mm1 Pancreas m m Peritoneum e e* . m Other Malignancies m2 Cardiac Diseases . 3 6 - Pneumoconiosis and Complications 24 2 Accidents and Suicides 1 1 1 Others -31 Total 7 17 8 who had at least 15 or more years of exposure to talc dust 1955-59 1960-64 5 1 1 m m 1r 6 8 2 1 25 3 m' m m 1 m am 8 9 2 5 28 1965-69 Total 2 13 13 2 -1 12 - 1 i* 13 , 7 30 4 29 1 8 ** 6 16 23 108 TV V ; . w- r r ;\. fabl#'4r. T-"1.0 '- , i<- - "V Death* and Expected Mortality from Cancer of the Lung and Pleura and of the Gastrointestinal Tract and Peritoneum Among Talc Workers 1940-1969 ! '' r ' " ,r - Deaths Lunq and Pleura Proportional Mortality (%) Observed Expected .1 P 1940-44 1945-49 1950-54 1955-59 1960-64 1965-69 0 - 0 2 - 11.7 1 - 12.5 5 20.0 3 ' 10.7 2 8.7 Total 13 P probability S * significant NS not significant - 2.0 3.1 4.3 5.7 6.7 7.7 i J -s s 8 NS NS Gastrointestinal Tract and Peritoneum ' :Deaths Proportional Mortality P --------- l Observed Expected 7 1 -1 -1 11 -3 1 2 n - 14.3 l 5.8 - 12.5 - 12.0 : 3.6 9.5 r, -7.8 1 7.8 -7.1 j 6.7 7 6.3 6U A. \ NS N$ INS NS NS NS 9 i *\ i\ \ / - 1940-44 1945-59 1950-54 1955-59 1960-64 1965-69 labi 5 Death and Expected Mortality From Cardiac Dise&sa Aaong Talc Vorkers 1940-1969 / f* Deaths Proportional Mortality (%) Observed Expected 3 42*8 6 35.3 00 * '24.0 0 28.6 I 20.4 32.4 41.0 46.0 46.5 46.6 45.5 Total 30 Table 6 Comparative Duat and Fiber Count at the Various Talo Mining and Milling Operations Pre 1945 through 1969 Dust Counts* i 22L Dust Counts* Fiber Coun\ Pre 194b Ave.** Med.** 1946-1965 Ave * * Mad*** 1966-1969 Ave.** Med.** Ave.** Med.** Drilling Mucking Crushing Screening Milling Garnering & Separating Pulverizing Bagging R R & Truck Loading 818 413 120 30 Pre 1948 180 69 69 61 92 75 278 -- ' 151 70 - 129 ---- 53 55 1948-1965 42 13 37 37 25 20 27 27 28 28 27 23 73 63 19 19 99 28 - 40 --1 .- 29 43 20 - 24 -- -- 25 20 7 7 33 35 . 15 --- 77 r 13 9 mm -- 27 > 27 s 36 28 3 2 62 -- 25 27 -- 47 24 Blow Room*** 1227 1196 - Open Chutes** 125 83 *Dust counts in nppcf| fiber counts in no* fibers/nl*>u in length **Ave. - averagej lied* - median Operation discontinued after 1948