Document 71B663dwRdLp6Zmpq0qzkmEka

FILE NAME: Asbestos in Schools & Other Buildings (AIS) DATE: 1991 DOC#: AIS004 DOCUMENT DESCRIPTION: Journal Article - Mesothelioma among Employees with Likely Contact with in-Place Asbestos-Containing Building Materials Annals of NY Academy of Science Mesothelioma among Employees with Likely Contact with in-Place Asbestos-Containing Building Materials12 HENRY A. ANDERSON, LAWRENCE P. HANRAHAN, JOSEPH SCHIRMER, DEE HIGGINS, AND PRISCILLA SAROW Wisconsin Division o f Health P .O .B ox 309 Madison, Wisconsin 53701 When construction workers completed their tasks, care of new buildings became the responsibility of maintenance employees. Sometimes obviously, and at other times insidiously, asbestos-containing building material (ACBM) deteriorated or was physically damaged, necessitating repair or replacement. Not identified as a public health priority, such maintenance was often deferred when it was not cosmetically necessary. Although the health hazard of asbestos exposure from thermal asbestos insula tion during building maintenance work was recognized as early as 1932,2 and concerns were raised about the potential health hazard of spray-applied ACBM in 19323 and 1953,4 quantitative industrial hygiene assessment of exposure circum stances was not begun until the 1970s.5,6 Health investigations have begun de scribing asbestos-associated diseases among workers exposed to ACBM during the course of their usual work.7-12 In 1984 the United States Environmental Protection Agency (EPA) conducted a national survey of buildings to estimate the extent of friable ACBM in existing structures. They concluded that approximately 31,000 schools and 733,000 public and commercial buildings were likely to contain such materials.13 Priority has been placed upon addressing the ACBM in schools. The Wisconsin Division of Health (WDOH) within the Wisconsin Department of Health and Social Services (WDHSS) has served as the lead agency for the U.S. Environmental Protection Agency's (EPA) School Asbestos Programs since 1979. Wisconsin has 429 public-school districts containing 1,923 schools with a total of 2,230 buildings. There are an additional 986 private-school districts containing 1,014 schools with 1,142 buildings, and 18 government-school districts (state, county) with 28 schools and 107 buildings. All these schools are regulated under the Asbestos Hazard Emergency Response Act (AHERA). Under AHERA regulations, all school districts were required to submit asbes tos management plans to WDOH for review by October 1988. The WDOH devel oped and maintains a computerized database program for storing data abstracted " This project was partly supported through cooperative agreements with the National Institute of Occupational Safety and Health (NIOSH) and the Agency for Toxic Substances and Disease Registry, No. U53-CCU500801 and No. U60-CCU502984, and the U.S. Envi ronmental Protection Agency, No. K005903. 550 ANDERSON et al.: DISEASE & CONTACT WITH ACBM 551 .during the management plan review. T able 1 summarizes the status of ACBM identified from the inspections done to prepare the AHERA management plans. Significantly damaged friable thermal system insulation was reported from 37% of the public-school districts, but from only 15% of the private-school dis tricts. Significantly damaged friable surfacing ACBM was reported by 4% of public- and 1% of private-school districts. While 96% of public- and 86% of private-school districts reported nonfriable miscellaneous ACBM (primarily floor and ceiling tile), only 2% of public and 0.2% of private districts found significantly damaged miscellaneous materials. Wisconsin Occupational Exposure and Disease Surveillance No national occupational exposure or disease surveillance program exists in the United States. The fragmented and unreliable status of our ability to charac terize the impact of past and future work-site exposures on the public's health was characterized first in 1984 congressional testimony14 and later in a 1987 report from the National Academy of Sciences.15 t a b l e l. Asbestos-Containing Materials in Wisconsin Schools: Summary of 1989 AHERA Plan Reviews Thermal Surfacing Miscellaneous Friable Damaged Friable Damaged Friable Damaged Public-school districts (n = 411) Privateschool districts (n = 872) 326 (79%) 424 (49%) 153 (37%) 78(19%) * 130(15%) 105 (12%) 16 (4%) 8(1%) 91 (22%) 9 (2%) 48 ( 5%) 2 (0.2%)' To begin to address occupational and environmental health surveillance needs in Wisconsin, the WDHSS entered into a five-year (1984-1988) cooperative agree ment with the National Institute for Occupational Safety and Health (NIOSH). The intent was to evaluate existing Wisconsin data systems for utility in occupa tional disease and injury surveillance and to pilot selective sentinel disease sur veillance. In 1987 the pilot surveillance activities were expanded under the NIOSH Sentinel Event Notification System for Occupational Risks (SENSOR) initiative to include sentinel physician reports and investigative intervention. METHODS Surveillance Data Systems Utilized 1. Wisconsin Vital Statistics Registration System (VSRS)16 The Vital Statistics Registration System in Wisconsin was converted to a computer data base beginning in 195.9. Cause of death is coded by a certified 552 ANNALS NEW YORK ACADEMY OF SCIENCES nosologist using current International Classification of Disease (ICD) codes. Usual occupation of the deceased, coded by a certified nosologist using the United States Bureau of the Census Codes, became part of the initial electronic file. Beginning in 1981, usual industry was coded and added to the VSRS. Multiple cause of death coding has been employed since 1973. 2. Cancer Reporting System (CRS)17 In 1978, Wisconsin implemented a statutorily mandated, population-based, state-wide, Cancer Reporting System (CRS). All primary neoplasms, except basal cell and squamous cell carcinoma of the skin, are reportable. The system is maintained by the Wisconsin Center for Health Statistics and obtains information from all acute-care general medical-surgical hospitals in the state. Each hospital ization is reported. The CRS identifies duplicate reports, and then serially updates each case record to reflect the most current and definitive diagnoses including t a b l e 2. ICD Cause of Death Codes Reviewed to Identify Mesotheliomas ICD-7 (1958-1967) 158 -- -- -- 197.9 -- -- 211 212 -- -- 227 -- -- ICD-8 (1968-1978) __ 158.9 -- 163.0 -- 199.1 -- -- -- 212.3 212.4 -- 228 -- ICD-9 (1979- ) _ 158.9 162 163.0 -- 199.1 199.9 -- -- -- 212.4 -- 229.9 findings at autopsy, if performed. The ICD-9 extension codes for Oncology histol ogy (morphology) are utilized. Annually, the VSRS records are electronically searched to identify CRS fatalities. Identified matches are then incorporated into the CRS data system. Physicians and pathology laboratories began reporting nonhospitalized pa tients with cancer in 1987. 3. Wisconsin Mesothelioma Surveillance The VSRS and the CRS form the basis of Wisconsin's mesothelioma surveil lance system. The electronic VSRS spans three International Classification of Disease (ICD) coding revisions; ICD-7 (1958-1967), ICD-8 (1968-1978), and ICD-9 (1979present). Unfortunately, until ICD-9, there were no codes specific for either pleu ral or peritoneal mesothelioma. ANDERSON et ah. DISEASE & CONTACT WITH ACBM 553 State nosologies were asked to identify the ICD codes most likely to have been used for mesothelioma during the periods of the different ICD revisions (Ta b l e 2). For the years 1959-1982, death certificates in the VSRS with these codes were identified and the individual microfilmed death certificate reviewed. Certificates with any mention of mesothelioma as a contributing cause of death were flagged. Beginning in 1983, a system was instituted whereby, upon receipt of a death certificate with any mention of mesothelioma, a nosologist would flag the certifi-. cate at the time it was coded and the epidemiology program was notified. The CRS informational base was searched for all mentions of ICD-9 extension, Oncology histology (morphology) codes, 9050-9053, which are indicative of me sothelioma. Cases that were not duplicates of the VSRS-identified cases were added to the surveillance system. It was feasible to reconstruct lifetime occupational histories from medical records (since 1983, all Wisconsin in-patient medical records must contain an occupational history) augmented by interviews with next-of-kin and treating phy sicians. State data sources, such as professional licensure records and public employee service records, could be used to verify reports concerning length of service and public employment classification. For school employees, current AHERA building asbestos inspection reports could serve to verify the presence of ACBM and its current status in school buildings. Descriptive Epidemiology This report is the first investigation to utilize the Wisconsin mesothelioma surveillance system. We chose to investigate mesothelioma deaths in which usual occupation or industry on the death certificate identified public building custodian/janitor/maintenance workers as well as commercial or manufacturing facility maintenance and repair employment.' Additionally, because there is public health concern that school teachers may be exposed to asbestos released from friable ACBM and therefore be at risk of developing mesothelioma, we investigated deaths of mesothelioma among school teachers. We began by reviewing the death certificate information on usual occupation and industry found in the mesothelioma surveillance system. This review led to 41 detailed mesothelioma case investigations. For this investigation, lifetime occupational histories were reconstructed uti lizing four sources of information. First, CRS data and medical records were sought and, when available, reviewed to verify the diagnosis and to identify occupational history and asbestos exposure references. Second, self-administered questionnaires were sent to next-of-kin requesting information including demo graphics, smoking history, educational attainment (including names of schools attended), military service, father's occupation, employment history since first job, and whether the informant believed the individual had been exposed to asbes.tos and how. Third, a telephone interview with the next-of-kin was attempted to obtain the exposre information contained in the questionnaire when the selfadministered questionnaire was not returned, or when information provided was incomplete or additional specific detail was desired. Fourth, for public employees, personnel and pension fund offices were queried to verify dates of public employ ment. 554 ANNALS NEW YORK ACADEMY OF SCIENCES t a b l e 3. Mesothelioma as a Cause of Death: Wisconsin Vital Records, 1959-1988 Sex Years of Death Female Male All 1959-1963 1964-1968 1969-1973 1974-1978 1979-1983 1984-1988 All 3 (75%) 1 (25%) 4 4 (57%) 3 (43%) 7 6 (32%) 13 (68%) 19 13 (36%) 23 (64%) 36 25 (23%) 86 (77%) 111 48 (27%) 133 (73%) 182 99 (28%) 259 (72%) 359 RESULTS Mesothelioma Surveillance The mesothelioma surveillance system (1959-1989) contains 573 mesothe lioma reports (160 females and 413 males). This includes 410 deaths with mesothe lioma identified as an underlying or contributing cause of death (397 Wisconsin residents and 13 nonresidents who died while in Wisconsin institutions). The CRS contains an additional 77 deaths among those with diagnoses of mesothelioma for which the death certificate did not specifically mention mesothelioma (74 resi dents and 3 nonresidents). The vital status of the remaining 63 Wisconsin resi dents and 23 nonresidents is unknown. Because the CRS was not in existence for all the years covered by the surveil lance system, mortality trends were examined utilizing only the information ob tained from the VSRS. Table 3 summarizes the 359 deaths in Wisconsin residents (1959-1988) which identified mesothelioma as an underlying or contributing cause on the death certificate. Data on some, but not all, deaths from 1989-1990 are available. The mesothelioma case mortality for the period 1979-1988, during which the CRS was fully operational, is summarized in Table 4. This includes all deaths ' among Wisconsin residents with diagnoses of mesothelioma, whether or not the death certificate mentioned mesothelioma. The CRS identified 19% more me sothelioma deaths than did the death certificates alone. Mesothelioma among Maintenance Workers Tables 5, 6, 7, and 8 summarize the occupational information obtained from the 29 detailed investigations of those identified as performing maintenance work. t a b l e 4. Deaths among CRS Mesothelioma Cases: 1979-1988 Sex Years of Death Female Male All 1979-1983 1984-1988 All 32 (23%) 64 (29%) 96 (27%) 105 (77%) 160(71%) 265 (73%) 137 224 361 ANDERSON et al.: DISEASE & CONTACT WITH ACBM t a b l e 5. Mesothelioma Deaths among School Maintenance Employees Identified by Usual Occupation and Industry on Death Certificate (DC) Case 1 Type: Pleura Sex: Male Age: 61 Year of death: 1979 DC Occupation: Custodian Lifetime Occupational History 1944-1947 U.S. Army Corps of Engineers; built bridges in Europe 1947-1967 Cement and masonry work; laid sidewalks, curbs, driveways for city, worked outdoors 1968-1979 General maintenance for public school district; cleaning, washing walls, ceilings, floors, DC Industry: minor repairs Public schools Case 2 Type: Pleura Sex: Male Age: 73 Year of death: 1980 DC Occupation: Painter DC Industry: School board Lifetime Occupational History 1925--1941 Painting; owned sign-writing business . . 1941-1946 1946-1968 Machine operator; cold metal forge company, stamping metal parts for military equipment School district paint crew; 75% indoors, painting logos on gym floors, washed and maintained walls and ceilings during school year, painted exterior and interiors full time during school recesses Comments: Reported being present during school renovations involving removal of asbestos materials. Employed in same school district as Case 4. Case 3 Type: Pleura Sex: Male Age: 65 Year of death: 1983 DC Occupation: Maintenance engineer DC Industry: Technical college Lifetime Occupational History 1935-1941 Part-time clerking jobs; pumped gasoline at small family-run station 1942-1946 U.S. Army; drove truck in Europe 1946-1951 Carpenter; building bams, some residential framing 1952-1980 Maintenance; vocational school, last 8 years supervised all maintenance staff. Participated in and later supervised annual cleaning and repair of boilers Comments: Maintenance department handled all but major renovations tinn in (t a b l e 5- C o n tin u ed ) Case 4 71 7 O1 S Type: Pleura Sex: Male Age: 74 Year of death: 1984 DC Occupation: Construction supervisor DC Industry: School board Lifetime Occupational History 1925-1942 ' Residential construction; father's building company 1942-1945 Machine shop; military equipment manufacturing plant 1945-1948 Carpenter contractor 1948-1957 City building inspector 1957-1969 School district general contractor; supervised for district the building of 5 schools; participated in multiple major repair and reconstruction projects, including ceilings Comments: Calcified pleural plaque noted; awarded worker's compensation. Employed in same school district as Case 2. ANNALS NEW YORK ACADEMY OF SCIENCES Case 5 Type: Pleura Sex: Male Age: 68 Year of death: 1985 DC Occupation: Custodian Lifetime Occupational History 1936-1940 Odd jobs, surface labor at coal mine 1941-1945 U.S. Army Infantry in Europe, shot in left lung 1946-1949 Carpenter; low-income home construction 1950-1952 School; studied printing 1952-1953 Shipping department; metal parts plant 1953-1955 Machine operator; metal parts manufacturing 1955-1975 School custodian; general maintenance, carpentry, painting, plumbing repairs 1975-1980 Public library; maintenance and repair Comments:- Colon cancer removed in 1954. DC Industry: School system Case 6 Type: Pleura Sex: Male Age: 62 Year of death: 1986 DC Occupation: Custodian DC Industry: Public school Lifetime Occupational History 1941-1945 U.S. Navy; catapult operator on aircraft carrier and battleship in Pacific 1946-1947 Telephone company; installing dial telephone systems 1947-1949 Clerk in store; part-time residential construction during summers 1950-1960 Paper manufacturing company; extrusion machine operator 1960-1961 Automobile tire sales 1961--1970 Sheet-metal shop; manufactured dryers for paper companies 1971-1986 Public school custodian; helped clean boilers each year; cleaning and maintenance during school year; building repair during summer. Comments: Wife believes asbestos was used in the paper industry dryer machines, but in the assembly area of the plant not the sheet- metal shop. He did not recall handling or seeing asbestos used in the sheet-metal shop. Case 7 Type: Pleura Sex: Male Age: 52 Year of death: 1987 DC Occupation: Facilities repairman DC Industry: University ANDERSON et al.: DISEASE & CONTACT WITH ACBM Lifetime Occupational History 1950-1972 Fishing tackle manufacturing; assembled lures 1972-1987 University maintenance, facilities repair; ACBM repair performed Comments: Worker's compensation awarded; friable asbestos containing thermal and surfacing material abated at the school; employed at same university facility as Case 10 Case 8 Type: Pleura . Sex: Male Age: 73 Year of death: 1987 DC Occupation; Cabinet maker DC Industry: Board of education Lifetime Occupational History 1937-1955 Street car/bus carpenter; repaired wooden seats, overhead compartments, rails 1955-1977 School board maintenance worker; worked in district-wide maintenance shop where all trades were housed: built cabinets in shop then installed in schools; repaired vandalism to schools; responsible for repair of all woodwork in schools; did painting Comments: Street-car work done in large single-room building where all types of public transit repairs were done. Wife believes their private home hot water heating system had ACBM Case 9 Type: Pleura Sex: Male Age: 77 Year of death: 1987 DC Occupation: Power plant employee DC Industry: Elementary school Lifeliitie Occupational History 1935-1940 Public service power plant; general labor, flue blower 1940- 1941 Truck driver; beer delivery 1941- 1957 School custodian; did every kind of maintenance including repair of broken pipes; kept boiler functioning 1958-1972 Tavern; owner/operator 1972-1974 Managed a drugstore Comments: Public-service power plant across from asbestos products manufacturing facility: lived within 1 mile of this asbestos-using plant (1935-1940) Case 10 Type: Pleura Sex: Male Age: 56 Year of death: 1989 DC Occupation: Custodian DC Industry: University Lifetime Occupational History 1950-1953 U.S. Army Air Corp; Korea, supply officer 1953-1966 Manufacturing/assembling juvenile furniture, cribs etc. 1966-1967 Night watchman; publishing company 1967-1973 Papermill; grinder room, debarking logs, chipping logs 1974-1977 Back injury (disability); part-time self-serve gas station 1977-1978 Unemployed 1978-1989 Maintenance custodian at university; cleaning, vacuuming, light bulbs Comments: Maintained auditorium with crumbling acoustical asbestos ceiling, heavy dust; vacuum bags had to be emptied by hand; very in i>n1 dusty. Employed at same facility as Case 7. 558 t a b l e 6. Mesothelioma Deaths among Public Building Maintenance Employees Identified by Usual Occupation and Industry on Death Certificate (DC) Case 1 Type: Pleura Sex: Male Age: 65 Year of death: 1974 DC Occupation: Plumbing inspector DC Industry: City Lifetime Occupational History 1926-1940 Plumber; repairs in residential buildings and some work installing pipes under streets 1941-1943 Shipyard; steamfitter/pipefitter building submarines 1944-1954 Master plumber; new construction and repairs 1954-1974 City plumbing inspector; visited work sites to assure new and renovated plumbing met codes Case 2 Type: Pleura Sex: Male Age: 60 Year of death: 1981 DC Occupation: Superintendent of building DC Industry: County Lifetime Occupational History 1942-1945 U.S. Navy; engineering aboard aircraft carrier 1946-1948 Theater; building maintenance 1949-1949 Tannery; laborer 1950-1980 County stationary engineer; initially full time in boiler room, then job expanded to include general maintenance in all county buildings; last 8 years located only in county courthouse doing maintenance and-custodial work ANNALS NEW YORK ACADEMY OF SCIENCES Case 3 Type: Pleura Sex: Male Age: 79 Year of death: 1983 DC Occupation: Captain DC Industry: City fire department Lifetime Occupational History 1923-1925 Tractor assembly company 1926-1957 1957-1977 Comments: City fire department; did all jobs, promoted to captain in charge of firehouse Building maintenance; did all general repairs and custodial work in sheltered workshop building Interstitial fibrosis on chest X-ray in 1979. Wife reports that for 2 years while working for fire department subject did part-time work with a furnace company doing service calls and may have been involved with one or two furnace installation jobs. She also reported that recently an outside contractor was brought in to do asbestos abatement in the workshop building he main tained. Case 4 Type: Pleura Sex:. Male Age: 70 Year of death: 1985 Lifetime Occupational History 1932-1939 Store clerk; CCC forestry camp 1939-1945 U..S. Army; Infantry (Europe, Africa, Italy) 1946-1948 Bar supplies sales 1948-1951 Railroad; brakeman 1952-1953 Brewery warehouseman DC Occupation: Building inspector DC Industry: City ANDERSON et al.: DISEASE & CONTACT WITH ACBM 1953-1958 1959-1962 1962-1966 1967--1972 1972-1984 1984 Residential construction; carpenter, concrete'laying Manufacturing; aluminum pots & pans Residential construction City building inspector Mobile home construction (part-time in Texas); applied liquid roofing material Return to Wisconsin Case 5 Type: Pleura Sex: Male Age: 64 Year of death: 1988 DC Occupation: Maintenance DC Industry: County Lifetime Occupational History 1942-1946 U.S. Army; radio operator in Alaska, some time spent as radioman on an army boat. 1946-1950 Bricklayer for residential construction 1951-1966 Switchman for railroad 1967-1970 General construction labor; built high school 1971-1978 Aerospace industry; missile parts 1979-1987 County courthouse; general maintenance and repairs Comments: Calcified pleural plaques noted on autopsy Case 6 Type: Pleura Sex: Male Age: 76 Year of death: 1989 DC Occupation: Electrical inspector DC Industry: City Lifetime Occupational History 1932-1939 Bank clerk; teller 1939-1941 City employee; electric meter reader 1941-1943 U.S. Air Force; flight simulator training instructor, no overseas duty 1943-1979 City employee; electricians union, did work in city electric power-generating plant, city building electrical systems repair & maintenance; also electric wiring inspector for city Case 7 Type: Pleura Sex: Male Age: 53 Year of death: 1989 DC Occupation: Electrician DC Industry: County Lifetime Occupational History 1953-1956 U.S. Marines; infantry radioman (Korea) 1956-1959 Machinery manufacturing; personnel office 1959-1963 Railroad; electrician apprentice 1963-1966 Automobile manufacturing; personnel office, time sheets 1966-1971 Electrician for electrical contractor; worked around insulation in ceilings, walls 1971-1983 Maintenance electrician for county; worked with cables, conduits, around ACBM UOll Comments. Became ill in 1983, malignant mesothelioma confirmed at autopsy; worker's compensation awarded. VS til s ANNALS NEW YORK ACADEMY OF SCIENCES t a b l e 7. Mesothelioma Deaths among Private Building Maintenance Employees Identified by Usual Occupation and Industry on Death Certificate (DC) Case 1 Type: Pleura Sex: Male Age: 51 Year of death: 1982 DC Occupation: Building services Lifetime Occupational History 1939--1963 Fanning 1963-1975 Bank building maintenance and painting; for initial 5 years did all pipe repair work needed 1975-1977 Maintenance supervisor for all bank properties Comments: Building maintenance crews handled all maintenance and repairs except major construction compensation; retired in 1977 owing to diabetic vasculitis DC Industry; renovations; awarded Bank worker's Case 2 Type: Pleura Sex: Male Age: 69 Year of death: 1986 DC Occupation: Supervisor paint shop Lifetime Occupational History 1935-1946 Pioneer Corps in Israel 1946-1958 1958-1960 1960-1973 Palestine Electrical Corporation; maintenance Emigrated to U.S.; cook, house painting Chair company; upholstering 1973-1986 Hospital; supervised housekeeping and maintenance for hospital DC Industry: Hospital Case 3 Type: Pleura Sex: Male Age: 67 Year of death: 1987 Lifetime Occupational History 1937-1941 Plastering and masonry work (residential) DC Occupation: Custodian DC Industry: Church ANDERSON et al.: DISEASE & CONTACT WITH ACBM 1942-1946 1946-1964 1964-1982 .S. Army Air Corps; parachute packer Master sand plasterer (no drywall) Custodian (church); maintained boilers, did painting, helped remove bowling alley from church basement (including tearing out old pipes) . . Case 4 Type; Pleura Sex; Male Age: 82 Year of death; 1988 DC Occupation: Janitor DC Industry: Fur company Lifetime Occupational History 1924-1930 House painter; interiors and exteriors 1930-1964 Truck driver; delivered live animals (hogs, chickens) to markets; delivered dressed meat to retail stores 1964-1969 Fur company; janitor/custodian; included maintaining and stoking coal-fired furnace and general building repairs Case 5 Type: Pleura Sex: Male Age: 77 Year of death: 1989 DC Occupation: Maintenance Lifetime Occupational History 1928-1930 Meat market; service counter 1931-1937 1938-1939 1940-1946 1946-1959 1959-1967 1967--1977 Comments: Assembler; metal furniture manufacturing, hospital beds Cheese factory Shipyard, manufacturing submarines; labor inside boats Dairy; whey processing; boiler room attendant; adjusted valves, gauges Disability for impaired vision Hospital custodian/maintenance; windows, floors; no climbing Shipyard work involved working between hulls DC Industry: Hospital mo t a b l e 8. Mesothelioma .Deaths among Industrial Maintenance Employees Identified by Usual Occupation and Industry on Death Certificate (DC) Ul Case 1 5 Type: Pleura Sex: Male Age: 49 Year of death: 1978 DC Occupation: General maintenance DC Industry: Industry Lifetime Occupational History 1944-1950 1950-1955 1955-1957 Naval shipyard; pipefitter Maintenance pipefitter; asbestos products plant G.S. Army; medical corps in Washington State 1957-1961 Maintenance pipefitter; asbestos products plant 1961-1976 Maintenance pipefitter; automobile manufacturing plant Comments: Father was a shipyard pipefitter; worker's compensation awarded; asbestosis with many ferruginous bodies noted at autopsy ANNALS NEW YORK ACADEMY OF SCIENCES Case 2 Type: Pleura Sex: Male Age: 36 Year of death: 1979 DC Occupation: Maintenance DC Industry: Landscaping Lifetime Occupational History 1962--1966 Farming 1966-1968 Department store clerk 1969-1970 Metal casting company; iron grills for fences, lawns 1970-1979 Landscaping for construction company; spreading gravel, hauling dirt, outside work Comments: Lived with parents; father worked 1941-1970 at an asbestos pipe-producing plant; brother and brother-in-law also worked at the same plant. Case 3 Type: Pleura Sex: Male Age: 45 Year of death: 1980 DC Occupation: Maintenance Lifetime Occupational History 1953-1954 1955-1956 1956-1958 Shipyard; general labor (yard built PT boats) U.S. Army; radioman Telephone company; repaired telephones 1959-1966 1966-1967 1967--1978 Maintenance, hospital; repaired boiler and pipes, general building maintenance Maintenance, chair-manufacturing company Maintenance, soda bottling company 1967-1979 Maintenance, part-time, then full-time general building maintenance for cheese marketing DC company Industry: Cheese company Case 4 Type: Pleura Sex: Male Age: 62 Year of death: 1981 Lifetime Occupational History 1935-1940 Fanning, CCC camp in Northern Wisconsin 1940-1945 Railroad; general labor, laid rail ties DC Occupation: Maintenance man DC Industry: Manufacturing 19461947- 1947 U.S. Marines; cook in Pacific 1980 Maintenance, fertilizer plant; helped build plant, then hired to maintain building & equipment, handled asbestos siding and roofing materials during repairs ANDERSON et al.: DISEASE & CONTACT WITH ACBM Case 5 Type: Pleura Sex: Male Age: 57 Year of death: 1981 DC Occupation: Building service man DC Industry: Paper mill Lifetime Occupational History 1943-1946 U.S. Navy; seaman on battleship in Pacific 1947-1951 Residential construction 1952-1960 Paper mill; building services, swept floors, changed lights, other semi-skilled 1960-1963 Paper mill wax line operator; feed & trim stock 1963-1972 Paper mill film extrusion machine operator; load & change rolls 1972-1974 Paper mill pumper; wax refinery 1974-1976 Paper mill graphic arts facility; load press cylinders 1976-1981 Paper mill building services; service of areas above 6 feet off ground, dusted grounds (care of grass & snow) jobs moving roll stock & vacuumed pipes and lights, walls; outdoor Case 6 .* Type: Pleura . Sex: Male Age: 43 Year of death: 1987 .* DC Occupation: Maintenance supervisor Lifetime Occupational History 1960-1963 Family farm work 1963- 1964 Plastics factory laborer; packaging machine 1964- 1967 U.S. Navy; engine boilerman in Pacific & Mediterranean 1968- 1968 Multiple factory labor jobs 1969- 1969 Welder apprentice; farm equipment manufacturing 1969-1979 Welder for dairy; maintenance, renovation & building projects 1979-1987 Maintenance supervisor for dairy Comments: Participated in the demolition of three dairy plants which contained asbestos installations DC Industry:. Dairy Case 7 Type: Pleura Sex: Male Age: 66 Year of death: 1989 DC Occupation: Maintenance supervisor DC Industry: Leather products Lifetime Occupational History 1944-1946 U.S. Army Infantry in Philippines 1946- 1947 Drove school bus 1947- 1948 Farming 1949-1954 Shipyard; in mold loft, pattern maker; construction of ore hauling ships 1954-1956 Janitor in public high school; cleaning & minor maintenance 1956-1985 Maintenance; leather products manufacturing plant; pipe & boiler maintenance, building repairs done, supervisor in later years 563 564 ANNALS NEW YORK ACADEMY OF SCIENCES All 29 of the maintenance workers reviewed were male and all were diagnosed as having pleural mesothelioma. The mean duration of maintenance work was 20 years, with a range of 5 to 36 years. Two school districts had each employed two of the ten school school mainte nance workers. Many occupational opportunities for potential asbestos exposure, in addition to maintenance work, were identified. However, for 10 (34%) of the 29 mainte nance workers the only identifiable source of potential asbestos exposure was derived from their maintenance work. For five (17%), histories indicated some prior employment in occupations and industries with probable asbestos expo sures: four had worked in shipyards and one person had shipyard and asbestos .product manufacturing facility employment. Opportunities for indirect occupational exposure were identified for ten who had spent time in the construction industry. Additionally, four had served aboard ship in the Navy, two of whom were likely to have spent time in the engine rooms of ships. One maintenance worker had household asbestos exposure and one had neighborhood exposure. If it is assumed that asbestos exposure began on the first year of employment in maintenance work, it is possible to evaluate whether latency periods were sufficient to make it plausible that maintenance work asbestos exposures contrib uted to the occurrence of the mesotheliomas seen. The mean latency from onset of maintenance work was 26 years. For three individuals the latency was less than 15 years (9, 9, and II years). Such short latencies would be unusual, unless we consider the possibility of earlier asbestos exposure during construction work for two and that the third had a history of significant household asbestos exposure as a child. If these possible asbestos exposures are included in the assessment of latency, periods from first identified exposure all exceed 20 years. Mesothelioma among School Teachers T a b l e 9 summarizes the occupational information obtained from investigation of the 12 school teachers. There were 6 male and 6 female teachers. All 6 males were diagnosed with pleural mesothelioma, while three of the six cases in females were of peritoneal origin. For 9 (75%) of the school teachers the only identifiable potential source of asbestos exposure was derived from in-place ACBM in their schools. One male teacher had spent one season in the merchant marine aboard an iron ore-hauling ship and had worked outdoors at a coal-burning electric genera tion plant while attending college. Two other teachers had worked in residential construction. Unexpectedly, two of the teachers were found to be sisters. In two instances, two teachers had taught for some time in the same school. AHERA information was available concerning the schools in which 8 of the teachers worked. Among these, 6 taught in schools containing friable surfacing material as well as thermal insulation. Two others taught in schools that contained only friable thermal insulation. The status of any ACBM in the schools of the other 4 teachers was unknown. DISCUSSION Mesothelioma Surveillance Consistent with worldwide observations over the past 30 years,18-20 Wisconsin has experienced a markedly increasing prevalence of mesothelioma deaths among ANDERSON et al.: DISEASE & CONTACT WITH ACBM t a b l e 9. Mesothelioma Deaths among School Teachers Identified by Usual Occupation and Industry on Death Certificate (DC) Case 1 Type: Peritoneum Sex: Female Age: 78 Year of death: 1968 DC Occupation: Teacher DC Industry: Teacher Lifetime Occupational History 1908-1910 Grade school teacher in North Dakota 1911-1920 Teachers College; taught elementary school teacher-training courses 1920-1959 Teacher at 2-year teacher preparatory college Comments: Father was a farmer; unmarried; no neighborhood exposures; sister of Case 2. Laparotomy identified normal ovaries and no primary tumor site; surgical tissue diagnosed as mesothelioma. Status of any ACBM in schools unknown. Case 2 Type: Peritoneum Sex: Female Age: 68 Year of death: 1970 DC Occupation: Teacher DC Industry: Public Schools Lifetime Occupational History 1923-1962 High school home economics teacher Comments: Father was a farmer: husband was a menswear salesman; no neighborhood exposures; sister of Case 1: diagnosis confirmed at autopsy. 1989 AHERA inspection found significantly damaged friable thermal insulation and friable surfacing material in the school. Case 3 Type: Pleura Sex: Female Age: 63 Year of death: 1980 DC Occupation: Waitress trainer DC Industry; Vocational school ,Lifetime Occupational History 1932-1976 Hotel and restaurant waitress 1962-1976 Part-time teacher in vocational school; traveled 2-3 times a week to state vocational schools throughout Northeastern Wisconsin to conduct waitress/restaurant training courses . 1977-1980 City parking ramp cashier Comments: Father was a farmer and part-time carpenter; unmarried; no factories near home; status of any ACBM in schools unknown. Case 4 Type: Pleura Sex: Male Age: 65 Year of death: 1980 DC Occupation: Music professor DC Industry: University Lifetime Occupational History 1935-1942 Drove taxi; played piano in bands while in college 1942-1946 Traveled with armed services bands entertaining throughout Europe 1947-1953 Completed college; obtained Masters in Music; played piano in bands 1953-1978 Professor of music at a university Comments: Father a history teacher; wife a teacher; no factories near home. Music practice rooms reported to have acoustical asbestos surfacing material; back of stage used surfacing ACBM; asbestos stage curtain uatn\i (TABLE 9. C ontinued) Case S Type: Pleura Sex: Female Age: 66 Year of death: 1980 DC Occupation: Teacher ui DC Industry: School district Si Lifetime Occupational History 1937-1942' Elementary school teacher 1943-1946 1946-1955 1955-1977 Comments: Office; secretarial work Taught all grades in rural school Elementary school teacher in different district Father was a farmer; husband ran a mink farm. Mastectomy in 1959: received radiation therapy. Mesothelioma on opposite side from mastectomy. 1989 AHERA inspections found friable thermal insulation and friable surfacing material in the schools she taught in in 1955-1977. Earlier school's ACBM status unknown. Case 6 Type: Pleura Sex: Male Age: 81 Year of death: 1981 DC Occupation: School teacher DC Industry: Education Lifetime Occupational History 1920-1974 Teacher at parochial schools in Texas, Oklahoma, South Dakota, Illinois, Minnesota, Wisconsin (history, math, Bible classes) 1920-1974 Carpenter during summers working on renovation, remodeling and new residential jobs Comments: Father was a fanner; wife a teacher; no military service; no neighborhood exposures. Status of any ACBM in schools unknown. ANNALS NEW YORK ACADEMY OF SCIENCES Case 7 Type: Pleura Sex: Male Age: 48 Year of death: 1981 DC Occupation: Professor of architecture DC Industry: University Lifetime Occupational History 1950-1952 Summer construction work; driving wood pilings at dam sites 1953-1961 1961--1981 Comments: University degree program; part-time work at a cement plant and electrical supplies wholesaler University professor of architecture; research on urban renewal Father was an engineer; commercial building, federal government projects in the Tennessee valley. While at cement company, subject helped with the cleaning of an old closed cement plant. Wife is an architect; home not near factories. University office contained asbestos covered pipes-- since removed as part of an asbestos abatement project. Case 8 Type: Pleura Sex: Male Age: 50 Year of death: 1984 DC Occupation: Teacher DC Industry: Public schools Lifetime Occupational History ' 1953-1954 Seaman on iron ore boats; coal passer 1954-1955 Paper mill machine operator (Idaho) 1956-1958 U.S. Army medic; EKG technician at Hawaii hospital 1959-1966 College; part-time/full-time work for power plant; worked outside with coal piles and coal transport system. Cut up scrap metal with welding torch for short time 1966-1968 Teacher corps in Texas; training in special education 1968-1984 Teacher; special education classes; football coach Comments: Father ran shoe repair store. Wife reports the coach's roonVofifice was in the basement of the school, had many pipes running through it from the boiler room nearby. Taught in same school as Case 10. 1989 AHERA inspection identified significantly damaged friable thermal insulation in all schools subject taught in. ANDERSON et al.: DISEASE & CONTACT WITH ACBM Case 9 Type: Pleura Sex: Female Age: 80 Year of death. 1985 DC Occupation: Teacher DC Industry: Secondary school Lifetime Occupational History' 1925-1946 High school teacher (Latin) 1947-1956 Homemaker 1957-1960 Part-time Latin & history high school teacher 1960-1967 Comments: Full-time Latin & history high school teacher Father ran a retail store: family lived in apartment on 2nd floor above store, basement unused but did have boiler and pipes which may have been covered with asbestos; husband was a high school teacher: no factories near residence. Taught in same school as Case 10. 1989 AHERA inspection'found significantly damaged thermal insulation and surfacing material in school Case 10 Type: Pleura Sex: Female Age: 49 Year of death: 1986 DC Occupation: Home economics teacher DC Industry: Education Lifetime Occupational History 1958-1959 North Dakota high school teacher (home economics) 1960-1961 Interior decorator 1962--1963 Wisconsin high school teacher (home economics) 1964-1966 Part-time Wisconsin high school teacher (home economics) .1966-1984 Full-time Wisconsin high school teacher (home economics) . Comments: Father was a railroad depot agent; husband a teacher; no environmental exposure. 1989 AHERA inspection identified friable thermal insulation in all schools subject taught in and significantly damaged surfacing material in one. Taught in the same school as Case 9 (1962-63) and Case 8 (1964- 66). Case 11 Type: Pleura Sex: Male Age: 91 Year of death: 1987 DC Occupation: Professor emeritus Lifetime Occupational History 1920-1925 Waiter in restaurant while in school 1925-1965 Electrical engineer; professor of mathematics at University Comments: No military service; father a fanner; no neighborhood industry. Status of ACBM in university unknown. DC Industry: University Case 12 Type: Pleura Sex: Male Age: 43 Year of death: 1987 DC Occupation: Teacher DC Industry: Elementary & high school Lifetime Occupational History 1964-1969 6th grade teacher 1970-1972 U.S. Army meteorologist in Vietnam and Germany 1972-1972 Returned to school for reading specialist certificate 1973-1986 Special education teacher traveling to all district schools Comments: Father a farmer; no neighborhood factories. 1989 AHERA inspections found friable thermal insulation in all schools subject taught in. Friable surfacing material in one school he began teaching at in 1973. un - 568 ANNALS NEW YORK ACADEMY OF SCIENCES both sexes. The five years from 1984 to 1988 accounted for close to the same number of mesothelioma deaths (182) as occurred in the preceding 25 years (177). As seen in Table 3 nearly three-quarters of all cases occurred among males. The ratio of cases in males to those in females has doubled from 1.3 (1959-1973) to 2.8 (1974-1988) as the number of male cases increased earlier and more rapidly. Over the past decade (1979-1988), the ratio of male to female cases (3.0) has remained constant. The magnitude of the increase in cases among Wisconsin females, espe cially over the decade 1979-1988 is greater than that reported by others.21 These differences may partly be due to our inclusion of data from more recent years (1986-1988). This observation in Wisconsin is undergoing further investigation. When Table 3 is compared with Table 4, it can be seen that over the period of CRS full implementation (1979-1988) the death-certificate-only data underesti mated mesothelioma deaths by 24% among females and 17% among males. Histo pathologic study of surgical biopsy or autopsy tissue was used to establish the final diagnosis in 99% of the CRS mesothelioma deaths. Mesothelioma Case Investigations Epidemiologic analyses utilizing death-certificate characterization of usual oc cupation and industry have been useful in occupational and environmental health research.22 We found usual occupation and industry as listed on the Wisconsin death certificate a useful starting point in identifying individuals for further inves tigation who were likely to have performed maintenance work or taught school for significant periods. While the listing of maintenance work on the death certificate was confirmed by the in-depth interviews, it must be kept in mind that in the mesothelioma surveillance system there are certainly more individuals who had performed maintenance tasks than are discussed here. It is likely that instances occur where maintenance was not considered the usual occupation of the individual by the physician completing the certificate of death. The full assessment of the contribu tion of maintenance work to the occurrence of mesothelioma in Wisconsin will not be known until we have gathered full lifetime occupational histories on all the mesothelioma surveillance system reports. We conclude that in the absence of access to complete lifetime occupational histories, usual occupation and industry as listed on the death certificate are useful in identifying individuals who are likely to have spent significant propor tions of their employment in the identified occupation and industry, but will miss others with short-term employment which may add to the cumulative risk of disease. Maintenance Employment Building or industrial plant facility maintenance work often requires skills in multiple trades (such as plumbing, carpentry, painting, electrical work, and pipe and boiler repair and maintenance). We found that in 23 of the 29 cases, the work performed was of such a general nature. Given the diversity of skills needed, it is not surprising that many of the maintenance workers had also worked in the construction industry and that five had worked in shipyards. General construction work has been identified as a possible source of intermittent asbestos and could have added to the cumulative lifetime asbestos exposure of our cases.22-25 ANDERSON et al.: DISEASE & CONTACT WITH ACBM 569 All of the maintenance workers were likely to have performed tasks around thermal asbestos materials. It was commonly reported that periodic maintenance of boilers and pipes was performed either by the individuals or in their vicinity. Mention of acoustical or surfacing mterial was less common. The patients reported in cases 7 and 10 in Table 5 were employed at the same university facility, which was known to have friable thermal and acoustical ACBM. A similar situation was described in the school district in which the patients in cases 2 and 4 in Table 5 had both worked. It is unlikely that these clusters are due to chance alone. An unexpected observation was that four (17%) of the patients had served 4-year enlistments in the U.S. Navy. Two (one a boilerman and th other an engineer) spent time in the engine room and were probably exposed to asbestos aboard ship. The other two served aboard ship and may also have been indirectly exposed. A recent report of the mortality of United Kingdom military serviceman (those with more than 5 years of service) found an excess of mesothelioma among the Royal Navy servicemen (7 cases of mesothelioma).26 Asbestos diseases have also been reported among long-term merchant seamen.27'28 It is important to consider military service when investigating possible sources of asbestos expo sure when mesothelioma develops. School Teachers This is the first report that systematically investigates possible sources of asbestos exposure among school teachers with mesothelioma. In 9 of the 12 cases, the only potential source of asbestos exposure identified was in-place ACBM. It was unexpected to find two teachers who were sisters. The occurrence of more than one mesothelioma in a family is a very rare event. The world medical literature contains less than 10 reports.of family clustering of mesothelioma.29-30In each instance, exposure to asbestos (occupational and/or environmental) has been identified. The two sisters in our series fit the pattern described in these reports-- sharing a similar tumor site and histology. It was postulated by both Martensson29 and Lynch30 that a hereditary predisposing factor may exist which is especially sensitive to induction by asbestos. If such is the case, our sisters probably re ceived their induction dose of asbestos from ACBM within their schools. AHERA reports indicate that friable thermal and surfacing material were present in the school of one of the sisters. The school in which the other sister taught no longer exists and no information is currently available whether ACBM was in the school. Considering the rarity of mesothelioma and the more than 3,000 schools in the state, it was unexpected to find two school clusters of two cases among the 12 teachers investigated. In both instances significantly damaged thermal and surfac ing ACBM was present in 1988-89. The status of ACBM at the time the teachers were in the schools is unknown. CONCLUSION Our investigation of mesothelioma cases in Wisconsin with school, residential, commercial and factory maintenance'and repair employment identified asbestos exposure in every instance. For most, the opportunities for asbestos exposure came from multiple jobs, including maintenance work. However, in 10 (34%), the only identifiable likely source of asbestos exposure was to in-place ACBM, proba bly intermittently disturbed while maintenance activities were performed. We 570 ANNALS NEW YORK ACADEMY OF SCIENCES conclude that building maintenance workers are at increased risk to develop mesothelioma from exposure to in-place ACBM. We report 12 mesothelioma deaths among school teachers. For 9, the only likely source of asbestos exposure was to in-place ACBM. Two teachers, with similar peritoneal mesotheliomas, were sisters. All previous sibling clustering of mesothelioma reports have identified asbestos exposure to the siblings. This sug gests that our two teachers must have been exposed to asbestos, most likely during each of their 40+ years of teaching. Especially for the maintenance staff in the public school buildings, the high prevalence (36%) of significantly damaged friable thermal insulation described in our AHERA plan reviews represents a serious concern and underscores the need for strict operations and maintenance programs including repair and/or removal of such material. Rapid implementation of rigorous operations and maintenance programs is needed to prevent future asbestos exposure to the large existing maintenance work force and the even larger population of building residents whose health may be jeopardized by episodic environmental contamination by inadequate maintenance and operational precautions. SUMMARY The occurrence of mesothelioma is a sentinel event in occupational and envi ronmental disease.1A mesothelioma surveillance system was established utilizing existing computerized Wisconsin vital statistics data maintained since 1959 and a Cancer Reporting System (CRS) established in 1978. Review of the death certificate listing of usual occupation and industry from 487 mesothelioma deaths in Wisconsin from 1959 to 1989 led to the investigation of 41 persons with likely exposure to inplace asbestos-containing building mate rials (ACBM): 12 school teachers, 10 school maintenance employees, 7 public building maintenance workers, 5 private building maintenance workers, and 7 commercial and factory workers performing maintenance activities. For 10 (34%) of the 29 maintenance workers the only source of asbestos exposure identified was their maintenance work. For five (17%) histories indi' cated some prior employment in occupations and industries with probable asbes tos exposures. Opportunities for indirect occupational exposure were identified for ten who had been employed in the residential construction industry. One maintenance worker was exposed to asbestos in the household and another had neighborhood exposure. For 9 (75%) of the school teachers, the only identifiable potential source of asbestos exposure was derived from in-place ACBM in schools. One teacher had spent a season in the merchant marine aboard an iron ore-hauling ship and 2 had worked in the residential construction industry. Two of the teachers were sisters, and in two instances, two teachers had taught in the same school facility. We conclude that individuals occupationally exposed to in-place ACBM are at risk for the subsequent development of mesothelioma. ACKNOWLEDGMENT We wish to thank the Center for Health Statistics of the Wisconsin Division of Health for their assistance in providing access to data from the Wisconsin Cancer Reporting System and Wisconsin mortality vital statistics. ANDERSON et ah. DISEASE & CONTACT WITH ACBM 571 REFERENCES 1. Rutstein, D. D., R. J. Mullan, T. M. Frazier, W. E. Halperin, J. M. Melius & J. P. Sestito. 1983. 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