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FILE NAME Talc TALC DATE 1979 DOC TALC164 DOCUMENT DESCRIPTION Book Chapter - Mortality and Morbidity Among Talc Miners and Millers in Italy -- -- --------------" ----" -- --"1--979 MORTALITY AND MORBIDITY AMONG TALC MINERS AND MILLERS IN ITALY G.F. Rubino G. Scansetti G. Piolatto Institute of Occupational Health of Turin University Zuretti 29 Torino Italy G. Gay Ospedale Valdese Pomaretto Torino Italy The mortality experience of workers engaged in mining and milling the Italian asbestiform talc of Val Chisone was previously described Rubino et al 1976 In that paper we expressed some doubt as to whether we could be fully confident in the comparison with the agricultural neighbouring population we had chosen as a control For this report therefore expected deaths were recalulated by using as a standard the deaths rates of the Italian Male Population These rates are available since 1951. We have examined mortality patterns for the observation period from 1946 through 1974 using for the first quinquennium the rates relevant to the year 1951. The years method according to Case and Lea was used Case and Lea 1955 The results of this further analysis are reported in Table 1. There is in both miners and millers a significant excess of overall mortality which in miners is mainly accounted for by respiratory diseases and within this category by pneumoconiosis In millers there were 4 deaths from simple pneumoconiosis or with superimposed tuberculosis In both groups a very low incidence of respiratory cancer was observed TABLE 1. Miners and Millers - Observed and Expected Deaths During 1946 - 1974 Miners Millers Number in study 1260 418 Cause of Death 0 E SMR 0 E SMR All causes Lung cancer malignant respiratory diseases Pneumoconiosis Tb associated with Pneumoconiosis Tb 560 8 109 58 13 23 446.9 172 33.1 ~ - 11.6 125 47 3292 - 198 < < .01 Treating observed number of death as a Poisson vanable No expectation was assumed for pneumoconiosis 193 4 18 3 1 8 164.4 6.1 12.4 - 4.1 117 66 145 - 195 a ae oe ... oa 1 no mi a Se - 358 RUBINO ET AL The mortality among miners according to cumulative dust exposure is shown in Table 2. Environmental information regarding the mines and mills the composition of the talc and the methods for allocating individuals to exposure categories were reported in the previous paper Rubino et al 1976 It should be stated however that all mention of dust counts in this paper represent respirable particles of 0.5 to 5.0 micrometers From Table 2 it is evident that an increasing trend of pneumoconi- osis and tuberculosis is associated with increasing exposure At the highest level of exposure which was estimated to be more than 5,665 mppef about 20 of total deaths were due to pneumoconiosis complicated or not by tuberculosis The relationship of mortality to the intensity of exposure is not consistent in millers Table 3 The four observed cases of pneumoconiosis are quite uniformly distributed in the three exposure levels Further investigations were carried out for these deaths among millers in order to confirm the certified diagnosis and to assess any possible exposure to other dust not previously recognized Additional data were provided by the National Institute for Insurance The description of these cases is reported in Table 4 For cases no 1 and no 3 exposure to free silica in addition to talc was found miner Case no 1 had also worked as a graphite for 9 years Case no 3 was qualified for pay rolls as a miller but he had at irregular intervals also worked as talc miner helper For case no 4 no additional data were available as no claim compensation was set up Case no 2 whose death was certified as due to tuberculosis was only exposed to talc milling Chest film showed rounded opacities which were classified according to UICC Classification 1970 as r 1/2 in lower pulmonary zones in addition to tuberculous sclerosis and calcifications Histological examination of necropsy specimens showed the presence of nodules partly hyaline with central necrosis similar to caseous necrosis Figure ) These nodules may hardly be considered as classical silicotic nodules However the origin not simply tuberculous is supported by the presence of several birefringent particles which were found the as well as within the fibrous thickening of the septa Figure 2 Infrared analysis and diffractograms of dust from digested lung demonstrated 85-90 of talc particles mixed with 10-15 quartz In conclusion the results of our study show a marked difference between miners and millers mortality as regards the incidence of pneumoconiosis The high frequency among miners is attributable to the high content of free silica in the air dust in the mines which was measured to be as high as 18 in drilling operations Rubinoet al 1976 Through our further investigations evidence was provided on one case of pneumoconiosis with tuberculous association following exposure to talc in a work- room where free silica content in the air dust was less than % This death occurred 29 years after first exposure in a worker exposed to an estimated average dust concentration of 24 mppcf for 23 years The role of the small amount of free silica in addition to talc in inducing such pulmonary fibrosis is still an open question Moreover superimposed tuberculosis may be implicated in the development of the fibrosis as it happens in Pulmonary Massive Fibrosis James 1954 However on the basis of results of investigations by Kleinfeld et al 1964 and Leophonte et al 1976 the experimental study of rats by Wagner et al 1977 and our present findings the biological possibility of a pneumoconiosis produced by asbestiform talc with low silica content emerges although clinical and histologi- cal aspects may differ in the various studies MOI AL. MORTALITY AND MORBIDITY AMONG TALC MINERS 359 nin 'oe YINS 2004 6S Ble - - 1Bb2] SoOt9peglrQocones gggs Zes JZ $80 ga ey - - s < Cc Fe =>~ ie) tS2 S 99 Ov ou ray BESeo YAS 170-565 tz 170-565 - - 002 GRGaR SMR Ser 3 L0et a> s6 - SMR se > 0 eer oe 9.5 316 316 Z ' FLOaelCsPESR eaNSOXZ YWS aun 3.5 ibSt - 20 bSl ISNG 0041 coe . > ajeINwWD 3 2 01 6e 8 ~ ~ 92 Aq CHR sywPEQ [e) SSL FA Sk (< e] v payedxy Rev Pue pavesqo seasip SIODWNEUG - (sueA-jodws Loyeadse 0 YM juebyw-UON sioucOWwNed SIBUIN $B) Apny yeag Z U1 jo yeours vos; sanedjiy Paleose FIGVL ainsodxg 30QlUN asneg un} SO 10 > Qi QL >d: dz RUBINO ET AL. YWS c^' - be - - es per< est "3g $29 we vs - ~ 61 0 29 0 e] t L YWS 137 249 Ort - - 1P9E Peb-ZeL Ze S | st SMR - - bt 49.5 0 6S L 9 2 (e) - 273sng yWS 11 002 364 - - Ele Zoi 621 > aAne|NWD 3 vlp St L2 - - bh Aq se d 0 eZ < 8 t 0 < pa1ledxg pue saesig SIOUDWNS (sued-jow Uoyeidsay PeAl-asO SJOIW se) Apms yjeog ED jueByw-LON SIOUDWNA, IVL ainsodx3 uiyaquiny joasnep Sasnes daoues Bun |ly UNM PAIBNOSse SO LO QL QL >ch >d- MORTALITY AND MORBIDITY AMONG TALC MINERS FIGURE 1. A module partly fibrohyaline with central necrotic area Hematoxylin and Eosin x 17 5 FIGURE 2. Fibrous thickening of alveolar septa with several birefringent particles Hematoxylin and Eosin Polarized light X40 RUBINO ET AL TABLE 4. Description of the Certified Cases of Pneumoconiosis Among Talc Millers Case Number 1 23 3 4 Duration of exposure yrs Latent period yrs Cumulative dust exposure as talc worker mppcf Other Exposures to Dust Death certification Necropsy findings Chest : ILO UICC category 3 33 991 Free silica 23 29 552.5 None 12 38 365.8 Free silica Silicosis Fibrohyaline nodules sclerosis Silico Fibrohyaline nodules sclerosis Silicosis Interstitial fibrosis 2/2 r pl tb 0/0 11 41 351.0 No information available Silicosis Not available Not available In order to assess the exposure level at which pneumoconiosis may occur we have undertaken a morbidity study on talc millers This is a preliminary report based on radiographic changes The persons under study were the 43 millers still working in the years 1975 - 1976 and qualified by not having other exposures to inorganic or organic dust Frequency of radiological opacities was assessed according to the estimated cumulative dust exposure Table 5 shows that radiographic changes of 1/0 ILOUICC category or above appear after a cumulative exposure of more than 160 mppcf with the observation of 2 cases classified as 1/1 and 1/2 confined to the cumulative exposure of more than 320 mppcf TABLE 5. Radiographic Changes Among Talc Millers According to Cumulative Dust Exposure Cumulative Dust Exposure as mppcf Mean value of mppcf within each category Mean duration of exposure years Number in Study - Irregular or rounded opacities 0/0 0/1 1/0 1/1 1/2 More than 1/2 -80 -80 45.8 7.5 8 8 0 0 Q is} 0 81-160 1316 15.5 11 8 3 fe) 0 0 0 161-320 246 8 21.8 13 4 5 4 0 0 0 320 + 4180 287 11 2 x 3 1 0 p type s type AL | ation le le we as kiny nic or ated ILO160 ed to MORTALITY AND MORBIDITY AMONG TALC MINERS 363 Results of this radiological examination indicate that rounded and irregular opacities consistent with pneumoconiosis can be found among these talc millers after an average duration of exposure of about 22 years at an average dust concentration of about 11 mppcf During the period these workers were exposed the content of free silica in air dust was approximately % or less In conclusion our findings show that no relationship has been found between Italian talc exposure and cancer whereas pneumoconiosis may be observed Based on the radiographic changes we have classified signs definitely consistent with pneumoconiosis 1/1 or more of rounded or irregular opacities may be found after an exposure of more than 320 mppcf which a means lifetime exposure to more than 8 mppcf assuming a 40 year working life Initial signs may appear after 160 mppcf which a means lifetime expsure to more than 4 mppcf It is suggested from this data that the current Threshold Limit Value does not prevent radiological signs of pneumoconiosis REFERENCES Case R A.M. Lea A.G Mustard gas poisoning chronic bronchitis and lung cancer Brit J. Prev Soc Med 9 62-72 1955 International Classification of Radiographs of Pneumoconiosis Revised 1968 1970 ILO Geneva James W R.L : The relationship of tuberculosis to the developmentof massive pneumoconiosis in coal workers Br J. Tuberc and Dis Chest 48 89-93 1954 Kleinfeld M. Messite J. Shapiro J. Kooyman O and Swencicki R Lung Function in Talc Workers Arch Environ Hith 9 559-566 1964 Leophonte P. Fabre J. and Pous J Albarede J.L. and Delaude A Les pneumoconioses par le talc Archives des maladies professionnelles de Medicine du Travail et de Securite Sociale 6 513-532 1976 a Rubino G.F. Scansetti G. Piolatto G and Romano C Mortality Study of Talc Miners and Millers J. Occup Med 18 186-193 1976 r Wagner J.C. Berry G , Cooke T.J. Hill R.J. Pooley F D. and Skidmore Animal experiments with talc Inhaled Particles IV Part II pp 647-654 Pergamon Press Oxford England 1977 + SA PES ey Menges te any vA vt ERI Hider ig) anya x eral ner pnceat Sep eriemares amcniats A me eietmenlan rn eae peren e Ba) ae Tad nai COPYRIGHT 1979 BY THE SOCIETY FOR OCCU- PATIONAL AND ENVIRONMENTAL HEALTH All rights Reserved NO PART OF THIS PUBLICATION MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM BY ANY MEANS ELECTRONIC OR MECHANICALLY INCLUDING PHOTOCOPY RECORDING OR ANY INFORMATION STORAGE AND RETRIEVAL SYSTEM WITHOUT PERMISSION IN WRITING PATHOTOX PUBLISHERS INC 2405 Bond Street Park Forest South Illinois 60466 Library of Congress Catalog Card Number 79-888179-898819 ISBN 0-930376-08-0 Printed in The United States of America SOCIET In Deceml Health Act cha in the workplac given low prior and decision w people and the protecting the t of the total envi Attempts t from newly dis surrounded the quate controls . In 1972 met in a series From these dis Health - mt examination of Represent from academia independent m groups The m universal dime SOEH act Through its w communication often different | problems ByF scientific and s ing to the exa occupational a With the p hopes to expar living environm By focusing pu ing the dialogu professional ar working towarc