Document oN2K9bMmzoqOLm2Nw56oLz77

.J ] ] J ] i 1 ) Pcrgamon A*t*. tittup. "ft- voMt.fciMrtKia'i.fc..lB-tjr. m.' ^ W? CmiA SocW, ./gjitpceShJSlaVtf% hk*Ki Sf*ftc lt AO iwtll fsterWi n GtAt Enula (XTO-TOS0 iI7.00 OJSU- biiaiei rixiclu vnr PI!: $0003-4878(96)00107-X fTRENDS IN OCCUPATIONAL GROUPS AND INDUSTRIES ASSOCIATED WITH AUSTRALIAN MESOTHELIOMA cases 1979-1.995 A. J. Rogers!, P. Yeungt, A. Johnson, J. Leigh+ and P. Davjdson$ rn Rogers OH&S, PO Box 2128. ClovcHy. NSW 3031. Australia; jWorkjafe Australia. PO Box 58, Sydney, NSW 2001, Australia: and NSW Workers' Compensation (Dust Diseases) Board, * S2 Elizabeth St., Sydney. New South NVulcf. Australia introduction Id the mid 1970s concern was raised by a group of occupational health profession`, compensation authorities and government regulators about the rising numbers mesothelioma cases occurring in the Australian community. Asbestos exposure ras known at this time to be a major contributor to the cases and certain industries lech as crocidolite mining at Wjuenoom. local asbestos cement production, ar-time gas mask construction and the manufacture of crocidolite covered welding ods had contributed to local cohorts. Most states by this stage had specific asbestos regulations designed to prevent health effects principally asbestosis in the mining r>d manufacturing workforce with compensation authorities conducting regular inspection and health audits. Despite the introduction of these contemporary control strategies mesothelioma Eases have continued to rise in line with the v:?ri<.i wide trend (Peto et a!., 1995). Although this increase can he attributed to the long latency effects of the historical esvy exposure to asbestos especially amphiholes. there is still considerable concern in the community in regard to the use of bound chrysolite products and to lithe legacy of asbestos products such 3S in public and private buildings. This study icvides an analysis of the trends that have developed in Australian mesotheliomas s a means of predicting future outcomes. MATERIALS AND METHODS Australian cases of mesothelioma have been collected by some state compensa tion authorities for more than 30 years and by a national registration scheme since .1979. Australian Mesothelioma Surveillance Program (3979-1985) This research project centred in the Commonwealth Department of Health was up by a diverse group of occupational health professionals to investigate [amongst other things the incidence and aetiology of mesothelioma in Australia [.(Ferguson er al., 1987). Detailed occupational and environmental histories were .obtained by direct interview with patients or next of kin and. failing this, work /> HWBUI0011454 1 1 1 ] ]$ ?} ] ] J ] ] 1) ] 124 A. S. Roger* ci at. associates. All histories were independently examined by two occupational.hygien ists who had considerable experience in investigating exposures in a range of asbestos manufacturing and user industries. The Australian Mesothelioma Register (1986-1995) The comprehensive collection and reporting of cases continued post 1985 (Leigh et al., 1991, 1996). Owing to a number of factors the data collected on each case became less substantive with reliance placed on local rather than central diagnosis, case histories were reliant on information provided from clinical records with the consequence of considerable variability of details, quality and interpretation of information. Central register data was reviewed and coded by two experienced occupational hygienists one of which was involved with the coding of the 1999-1985 cases. The SSW Worker's Compensation (Dust Diseases) Board. (1985-1995) As part of the requirements of the "no fault" compensation scheme for dust diseases operating in the State of New South Wales (NSW), data is collected on asbestos related diseases associated wish employment in that State (DDB, 1995). Detailed occupational histories are obtained by direct interview which is followed up by industrial inspectors who conduct field inspection of premises and employer records and prepare a report to the independent medical panel. RESULTS In the period 1979-1995, 3538 cases were collected nationwide with an increase of 6-7% p.a. although this varies considerably across different industries and occupations (Tables 1 and 2). Five industries are typical of the differing trends found during the period of study and show' the considerable influence of exposure to amphiboles. The building industry produced the largest number of cases and also the largest increase (n - 5S9, 448%) across a wide range of occupation's'. Some cases recalled being present when "Limpet"' (mainly amositc and crocidoliie in Australia) was sprayed by insulation workers. Trades such as electricians and plumbers indicated that they had disturbed a variety of asbestos products whilst carrying out repairs, renovation or installation of new services. Marty carpenters and labourers indicated that they bad worked with asbestos cement products which were commonly used in domestic and commercial construction in the 1950s, 1960s and 1970s. Shore based shipbuilding, repair and demolition accounted for the second largest industry group. Case numbers appeared to have remained steady With a variable but slight increase of around one case per year. The majority of these were involved in boiler and engine repairs which involved the disturbance of asbestos lagging. Other trades Such as shipwrights, welders, plumbers and electricians indicated working with asbestos however and only a small proportion of cases listed their occupation as ships faggers. The local asbestos cement production industry ranks third in overall cases with an increase of approximately 5% p.a. although there is some evidence from Fig. 1 that this rate may have plateaued in the last 5 years. Almost all cases have arisen i HWBUI0011455 1 1 Jd s t J e f I !! J 3 3 1 Australian oicMJihslipnia cases 1979-3995 iis Table l. Industry distribution of mesothelioma cases in ihtee different. perfected. Industry Mesothelioma Program 1979-85 Mesothelioma Register 1986-90 1991-95 Primary asbestos industries Wiftenoom ctocidolitc mining/milling ~9 66 49 Asbestos cement production Insulation manufacture/installation Stevedoring 53 S5 a n 16 26 n 27 .34 Primary asbestos user industries Ship constructidnSrepairrilcmolilion Building Railway loco fabricution/maimcnincc Coal fired power station construction and maimcnancc JCS 65 45 29 SI 132. 203 291 29 63 32 -47 Secondary uscrfproduct contact Engineering labricaiion-'rcpaif Metal smelting Chemical plants Motor vehicle repair 15 so ss in 2 27 in ' 18 7 7 16 24 Other industries 301 341 271 Insufficient informatioiVunknowr, 137 218 383 Total BiS 1170 1510 Table 2. Occupational distribution of mesothelioma cases in three different periods Occupation Mesothelioma Program 1979-85 Mesothelioma Register 19SS-90 1991-95 Building trades Carpenters Electricians Plumbers Builders tabcut'ers Palmers Plasterer? Bricklayer (insulationtfuinsce) Bricklayer (non-insulation) Metal and engineering trades Boiler makers & assistants . Welders Car mechanics Shipping Ablcscamen Stokcls Marine engineers Wharf labourers 63 25 13 0 6 3. 3 fl 50 IS t 1 f l 21 107 1SS 30 59 29 39 34 35 25 24 4 11 5i S7 76 69 7 15 16 24 6 ____ 17 37 10 13 19 33 from employees who commenced in the era when dim levels were relatively high and crocidolitc was used (Boyle and Rogers. 1993). This industry had been operational from 1916 to 19B7 and used at its peak over 90% of alt asbestos fibre mainly in the form of roofing and cladding. By 1954 this accounted for 25% of new housing and a world ranking of four in per capita consumption. Imported w*t ! 14M : i! III ,n HWBUI0011456 'l' t 1 1 ] ] ns A. i, Roger* et u(. Ycir Re. I. crocidolite, amosite and chrysottle and local sources of crocidolite and chrysotile were used in various combinations throughout the history of the industry. Crocidolite mining, milling and associated activities at Wittenoom which ran in a number of phases from 1937 to 1966 ranked fourth and there is clear evidence that the numbers have been gradually decreasing over the last 7 years. Most of the cases were as a direct exposure at the various mines and mills whilst others we involved in transportation or the use of tailings for local road and concrete construction. Environmental cases from non mine employees such as women, children and town visitors are not included in this study having been reported elsewhere (Rogers 3nd Nevill, 1995). Although the infamy of the Wittenoom mine gives the impression that Australia was a major producer of asbestos, more than 95% was imported from Canada and South Africa (Boyle and Rogers, 1993). The stevedoring industry which was responsible for unloading both imported and locally produced crocidolite and chrysotile shows a steady increase of approximately 3-4% in cases. A group of primary asbestos user industries such as railway loco const ruction and repair, various engineering and metal fabrication groups and coal fired electric power stations have combined contributed 11% of cases and the number of cases from each industry has increased more than 50% since 1980. All of these industries involved the large scale use of both bulk crocidolite and bulk amosite along with chrysotile products such as rope, cloth and board. A steady rate of approximately 60 cases per year arose from a wide variety of both large and small industries. These involved jobs where the potential contact with amphibote or chrysotile asbestos ranged from negligible to highly likely. DISCUSSION Although a steady increase in mesothelioma over all industries and occupations cases is observed, there appear to be at least two separate groups. Cases arising from primary asbestos industries appear to have plaieaued and for Wittenoom they are on the decline. This is in line with predictions made using proportional latency jo: 60 - so S ao - 30 - z. 20 10 - t calculation particular!} and Nevill. and post th numbers fo compound) The abo\ ' primary asl asbestos prt which were product ma building ind of NSW uni: usually insm products we difficulty refasbestos con indicate that 4 or 5:1 since the ratio of caution in a; asbestos exp intermittent . tools which cj in the workft immigration j In examini mesothelioma al hygiene prt control of du; HWBUI0011457 J :i ] :.i * i I I wi ) Austtalian mesothelioma CjseJ. 197J*1$95 Mesothelioma sorveillucc program McieiDelioma register \tt Ship building and repair o Building indusuy 1980 1981 1982 1983 1934 IMS I9U 1987 S3s3 1989 1990 1991 1992 1923 1999 1995 Year Fi. a. H calculations made for these industries which ceased contact with amphiboles. particularly crocidolite, some 20-30 years ago (Bovje and Rogers, 1993; Rogers and Nevill, 1995). Data from the census of U.K. asbestos workers employed preand post the 1969 Asbestos Regulations, also indicates a decline in mesothelioma I' numbers for those manufacturing industries such as asbestos cement and asbestos . compounding that traditionally used amphibole asbestos (Hutchings cl ol., 1995). The above group is in sharp contrast to those industries who were users of the primary asbestos products and in trades where contact was made with in situ asbestos products. These industries were not included in early asbestos regulations which were usually specific!)- designed to prevent disease in asbestos mining and product manufacturing. Of particular concern are the trades associated with the building industry which were not covered bv specific legislation in the largest State of NSW uotii 19S3. For post 1955 cases collected in the national Register, there was usually insufficient information in the occupational history to determine if asbestos products were used and if so to what extent exposure occurred. To overcome this difficulty reference was made to the NSW DDB cases where considerable details on asbestos contact had been gathered. Building industry cases shown in Figs 2 and 3 indicate that the ratio of national to NSW cases has risen from approximately 2:1 to 4 or 5:1 since the change in programme to register information. This is higher than the ratio of 3:1 across all industries (Leigh ci at., 1996). The differences urge caution in assigning of all cases from the building trade being associated with asbestos exposure in that industry although it had the potentiaUbr continued intermittent contact during renovation and repair, introduced the use of power tools which created higher potential fot dust exposure and had considerable growth in the workforce particularly during the post war industrial expansion and later immigration programs. In examining the industry trends against the overall increasing numbers of mesothelioma it is possible to observe how the implementation of good occupation al hygiene practice such as the technical prohibition on the use of amphiboles, the control of dust emissions, adequate legislation and enforcement and removal of *i i 1 *#. f 1 i s I HWBUI0011458 A. J. Rogers el el. w .] 1 M ] Ti ] Fij. 5. pc asbestos from buildings and ships has lead to a reduced mesothelioma risk in the workforce albeit due to latency effects it has taken some 30-40 years for the results to show. Controls introduced later in the asbestos user industries will not show up in reduced mesothelioma numbers til! around 2010- de ln addition to data presented in this study, the reporting of cases not associated D. J with significant occupational exposure has increased and this has resulted in conflicting reports as to the significance of intensity of exposure, trace environmen Ot ba tal, low level occupational and chrysolite exposure or non-asbestos background oc mesotheliomas as contributing factors to mesothelioma in Australia. 19- ob tht REFERENCES Boyle, M. and Rogers. A. (1*393) Mesothci.c-ir.*. esses--the experience of the Australian asbestos cement manufacturing indust.-v. zvoi'f .v* /TV.* Annuel Conference oi the Australian fnxtiture of Occupational Hygicnots. pp 131--155. A:GH PO feo 1305. Titlljmsrine Vic 3Cs3, Australia. 1995 Report of the NSW Workers' Ccmpe.-.xutloi: (Dust Diseases Board) (1995) S2 Elizabeth St.. J Sydney 200C. Australia. Ferguson. D. A.. Berry. G.. Jcllhir-sky.'f.. Arust-cas. S.. Rogers. A.. Chung Fung. S.. Griinwood, A. foi po ] and Thomson. R. (I9S7) The menuhe .Nuria surtsitliiiicc program 1979-19S5. Med. J. Ausi. 147. 166-112. Hutchings. S.. Jones, 1. and Hodgson. J. t.1995: Occupational Health--llteennittlSupplement. Chapter 9. pp. 121-152. Asbestos related cise.iv;>. UK Heai:l; and Safety Exccutive.-HM Stationery Office, London. on j CO? col Leigh. J.. Corvalan. C.. Griiitwccd. A.. Berry. Cl.. Ferguson. D. A. and Thompson. R. (1991) The incidence of malignant mesothelioma in Australia. 19S2-19SS. Am. J. md. Med. 20. fri3-653. J Leigh. J.. Hull, B. and Davidson. P. (1996) The incidence of mesothelioma in Australia 1992-1994 and Australian mesothelioma register report. 1996 National Institute of Occupational Health and Safety, PO Box 58. Sydney. NSW 3W1. Australia. Pc to. J.. Hodgson, J., Matthews, F. and Jones, J. (1995) Continuing increase in mesothelioma mortality J in Britain. Lancet, J4S. 5*5-539. Rogers. A. and Nevitl, M. (1995) Occupations! and environmental mesotheliomas due to crocidolitc mining activities in Wittenoom. Western Au>;rxua Scond. i. Wort Environ. Health 21. 259-264. prr pn risl the 1 n HWBUI0011459