Mesothelioma and asbestos in the Province of Quebec, 1969-1972

All records of patients who died of mesothelioma in the Province of Quebec during the period 1969-1972 were collected and reviewed. Asbestos exposure in this group was compared with that in two control groups, one of persons dying of accidental causes and the other of those dying of cardiovascular disease. The mortality rate for mesothelioma was estimated at between 2.3 and 2.8 per million per year. Men were affected twice as frequently as women, this difference being related exclusively to pleural mesothelioma. The incidence in urban regions was much higher than in rural areas, and areas involved in mining showed an incidence in the expected range. Thirty-four percent of the patients with mesothelioma and only 2% of controls had histories of direct exposure to asbestos. This exposure was related to asbestos processing and not its production. No woman gave a history of occupational exposure to asbestos. It appeared that chrysotile may be less related to the production of mesothelioma than other types of asbestos fibers.     

Environmental asbestos exposure in rural Turkey and risk of lung cancer

The aim of this study was to determine the risk of lung cancer in a cohort of villagers with environmental asbestos exposure. The study was carried out as a field-based epidemiological study. Information from 3143 individuals in 15 asbestos exposed villages and 2175 individuals in 12 control villages was obtained. Asbestos fiber type to which villagers were exposed mainly was tremolite or tremolite, actinolite, chrysotile mixtures. The cumulative fiber count of the villagers during their lifespan ranged from 0.19 to 4.61 fiber-years/ml. The annual average incidence ratio of lung cancer was 135.21/100,000 persons/year in men and 47.28 in women in the asbestos exposed villages. For the control villages, this ratio was 60.15/100,000 person/year in men and 15.06 in women. Being a male, advanced age, smoking and asbestos exposure were established to increase the risk of lung cancer. Environmental asbestos exposure in rural area is a risk factor for lung cancer independent of smoking.     

A cohort study on mortality among wives of workers in the asbestos cement industry in Casale Monferrato, Italy.

The study investigates mortality from cancer and other diseases in a cohort of wives of asbestos cement workers in Casale Monferrato (northwest Italy). After the exclusion of women with an occupational record in the asbestos cement industry, the cohort comprised 1964 women. Their domestic exposure was estimated according to their husbands' periods of employment in the plant: 1740 had a period of domestic exposure whereas the remaining 224 married an asbestos cement worker only after he definitely stopped his activity in the asbestos cement plant; these have, therefore, been considered as unexposed. The cohort of wives was constructed entirely through official records in the town offices and is both exhaustive and unaffected by recall bias. At the end of follow up (1988) 1669 women were alive, 270 were dead and 25 (1.2%) were untraced. Main mortality analyses were only up to age 79 to reduce the misclassification of causes of death. Expected mortality was based on local rates. Mortality analyses were limited to the period 1965-88 due to the availability of local rates: in that period 210 deaths occurred among women with domestic exposure v 229.1 expected. There were four deaths from pleural tumours (one diagnosed as mesothelioma at necropsis) and six from lung cancer v. 0.5 and 4.0 expected respectively. Two further cases of mesothelioma were diagnosed by histological examination after the end of follow up. None of the three wives with histologically diagnosed mesothelioma had been engaged in industrial activities. Corresponding information for the other three cases could not be traced.     

Asbestos exposure in a shipyard area, northeastern Italy

The Monfalcone area, northeastern Italy, is a small industrial district (population 60,000), with a large shipyard. In order to monitor asbestos exposure in this area, a series of 3,640 necropsies, carried out at the Monfalcone Hospital between October 1979 and September 1998, were investigated. The thoracic cavities were examined for pleural plaques; these were classified into three classes (small, moderate, large). Routine histological sections of lung tissue were examined for asbestos bodies. Isolation and counting of asbestos bodies were performed in 1,075 cases. Lifetime occupational data were collected in 1,277 cases. Pleural plaques were observed in 70.5% among men and in 23.8% among women. The prevalences of pleural plaques did not show significant variations during the study period. Asbestos bodies were found on routine lung sections in 23.7% of men and 3.0% of women. The shipyard workers, the most numerous category in the series, were characterized by high prevalence of pleural plaques (total 86.7%, large 32.4%), high prevalence of asbestos bodies on routine lung sections (35.3%), and high amounts of lung asbestos bodies after isolation. The present data indicate that asbestos exposure may reach alarming levels in the shipyard areas.     

Asbestos exposure and ovarian fiber burden

Epidemiologic studies suggest increased risk of epithelial ovarian cancer in female asbestos workers and increased risk of malignancy in general in household contacts of asbestos workers. Ovaries were studied from 13 women with household contact with men with documented asbestos exposure and from 17 women undergoing incidental oophorectomy. Ovarian tissue was examined by analytic electron microscopy. Significant asbestos fiber burdens were detected in 9 out of 13 women with household asbestos exposure (69.2%), and in 6 out of 17 women who gave no exposure history (35%). Three exposed women had asbestos counts over 1 million fibers per gram wet weight (23%), but only 1/17 women without an exposure history had a count that high (6%). Although asbestos has been documented as a contaminant of some older cosmetic talc preparations, the chrysotile and crocidolite types of asbestos we detected are more indicative of background and/or occupational exposure. This study demonstrates that asbestos can reach the ovary. Although the number of subjects is small, asbestos appears to be present in ovarian tissue more frequently and in higher amounts in women with a documentable exposure history. © 1996 Wiley-Liss, Inc.     

Smoking habits and lifetime occupational exposure to gases or dusts, including asbestos and quartz, in a Norwegian community

Past or present occupational airborne exposure was recorded with a self-administered questionnaire sent to a random sample (N = 4992) of the 15- to 70-year-old population of Hordaland County, Norway. Completed questionnaires were returned by 90% of the sample. The respondents comprised 39% smokers, 20% ex-smokers, and 41% nonsmokers. Altogether 46% of the men and 12% of the women had a history of occupational gas or dust exposure. Occupational asbestos exposure was reported by 10% of the men and 0.4% of the women, and quartz exposure had been experienced by 8% of the men and 0.4% of the women. Smokers with a history of asbestos exposure represented 5% of the male population. Thirty percent of the smokers reported having been advised to stop smoking by a physician. The asbestos-exposed smokers had not received such advice more often than the smokers not exposed to asbestos. The findings indicate that airborne occupational exposure is widespread in the Norwegian County of Hordaland.     

Environmental exposure to asbestos in the area around Goor has been established as the cause of pleural mesothelioma in women

OBJECTIVE: To determine whether a disease cluster of 22 additional cases of pleural mesothelioma among women could be attributed to environmental asbestos exposure due to asbestos fibers from waste material on roads and property yards. The women studied were observed in an area with substantial environmental exposure to asbestos during the period 1989-2002. DESIGN: Ecological study. METHOD: In the study period of 1989-2002, all cases of mesothelioma among women, based on a strict histopathologic definition, occurring in the region of Twente, The Netherlands (n = 59) were provided by the regional cancer register. Additional information was collected on the occupational histories of the cases and their partners and addresses of residence through medical records, general practitioners, and next-of-kin. Environmental asbestos exposure was assigned to all cases that had had a long-term stay in a house in the area around Goor with demonstrated local environmental asbestos pollution and where any contact with asbestos through occupation or in the household had been excluded. RESULTS: In the risk area around Goor, out ofa total of 28 cases ofwomen with pleural mesothelioma, asbestos in the environment was found to be the only source of asbestos exposure for to women. In a further 4 women, environmental asbestos exposure was found to be the most likely cause of pleural mesothelioma. The average cumulative exposure was around 0.11 fiber/ml x exposure years. The observed extra incidence of 22 cases was attributed to the environmental exposure to asbestos in 64% (14/22) of cases. CONCLUSION: The environmental pollution to asbestos waste materials in the area around Goor was the main cause of the strongly increased incidence of pleural mesothelioma among women in this area. Taking into account an equal risk among men, the consequences of asbestos exposure in the area around Goor in the next 25 years are likely to result in 2 cases of pleural mesothelioma each year.     

Asbestos-related mesothelioma in monfalcone,Italy

The Monfalcone area, in northeastern Italy, is a small industrial territory (population about 60,000), with a large shipyard. Between October 1979 and April 1992, ninety-two malignant mesotheliomas were diagnosed at the Monfalcone Hospital. The series included 84 men and 8 women, aged 42 to 89 years (median age 68 years). There were 89 pleural and 3 peritoneal tumors. Seventy patients (69 men and 1 woman) had worked in the shipyards; six were seamen, and four insulators. Five men had been exposed to asbestos in various industries; six women had histories of domestic exposure, and one woman had a history of possible environmental exposure. The latency periods (intervals between first exposure to asbestos and diagnosis of the tumor) ranged from 20 to 65 years (median 52 years). Latency periods among insulators were significantly lower than among shipyard workers, as well as lower than among the other categories (p<0.01). Lung asbestos bodies were isolated after chemical digestion in 73 cases at necropsy, and in two cases at surgery. In necropsy cases, asbestos body burdens ranged between 100 and 10,000,000 bodies per gram of dried tissue (median 11,000). Pleural plaques were observed at necropsy in 62 out of 73 cases, and in two cases at surgery. In the time period we considered, the annual incidence rates for pleural mesothelioma were very high among male Monfalcone residents, being 189 per 100,000 among people aged 75 years or more. On the basis of occupational data and of objective signs (lung asbestos bodies, pleural plaques), all the cases of the present series but one (that with possible environmental exposure) were considered as asbestos-related. The role of co-factors in the development of asbestos-related mesothelioma is suggested. © 1993 Wiley-Liss, Inc.     

Malignant mesothelioma of the pleura among women

BACKGROUND: The epidemiological features of mesothelioma among women differ from those observed among men. OBJECTIVES: To trace the outline of pleural mesothelioma among women in the Monfalcone area, Italy. METHODS: Thirty-three malignant mesotheliomas of the pleura observed in female patients at the Hospital of Monfalcone, Italy, in the period 1979-2002 were reviewed. The diagnosis was based on/or confirmed by necropsy findings in 30 cases. Occupational and social histories were obtained from the patients themselves or from their relatives by personal or telephone interviews. In 29 necropsy cases thoracic cavities were examined for the presence of pleural plaques. Routine lung section were examined for asbestos bodies in 30 cases. In 21 cases asbestos bodies were isolated and counted after chemical digestion of lung tissue. RESULTS: The age of the patients ranged between 48 and 89 years (mean 72.85, median 73.00). All the patients had histories of exposure to asbestos, single in 25 cases and mixed in 8. Exposure at home due to cleaning of work clothes was the most frequent type of exposure. Various patients had been exposed in non-asbestos text industries (cotton mills). Unusual types of exposure occurred in some cases (distillery, small sodium carbonate factory, starch factory). The latency periods (time intervals elapsed between first exposure to asbestos and diagnosis of the tumour), calculated in 23 cases, ranged from 34 to 62 years. Pleural plaques were found in 21 cases. Twelve patients showed asbestos bodies on routine lung sections. The asbestos body burden ranged between only a few bodies and 92,000/g dried tissue. CONCLUSIONS: In contrast with other series of mesothelioma among women, all the present cases were attributable to asbestos. The detection of objective signs of exposure (pleural plaques, lung asbestos bodies) played a key role in attribution.     

Malignant mesothelioma in Basse-Normandie, a French population study. Descriptive analysis, prognostic factors and survival

BACKGROUND: Malignant mesothelioma is a pleural and/or peritoneal tumor closely related to asbestos exposure, and its incidence should continue to increase during the first two decades of the 21(rst)century. The main prognostic factors described for this tumor are older age, sex, tumor stage and histological type. The aim of this study was to assess the incidence of pleural and peritoneal malignant mesothelioma in the County of Basse-Normandie (France), as well as their epidemiological characteristics, and the prognostic factors related to survival duration. METHODS: Cases were identified through repeated inquiries among all chest physicians and pathologists of the County of Basse-Normandie. A special care was taken in the validation of the diagnosis of each case. Incidence of mesothelioma was determined according to sex and age (5 years categories). Qualitative and quantitative variables were compared with the use of chi-square or Student's t tests respectively. Survival rate was calculated by Kaplan-Meier method, and prognostic factors were studied by means of Cox model. RESULTS: Study population consisted in all 80 malignant mesothelioma cases diagnosed in Basse-Normandie between the 1(rst) of September 1995 and the 31(rst) of August 1999. Annual incidence rates of pleural mesothelioma were 1.1/100 000 in men and 0.23/100 000 in women; annual incidence rates for peritoneal mesothelioma were 0.21/100 000 in men and 0.13/100 000 in women. Asbestos exposure was present in 63 cases (78.8%). The study of geographic distribution of mesothelioma cases revealed the influence of the main asbestos industrial settings, as well as the numerous scattered cases related to other occupational exposure. Mean survival duration was 9 months for pleural mesothelioma and 5 months for peritoneal mesothelioma. After adjustment on age, death risk was higher in asbestos-exposed than in non asbestos-exposed cases. CONCLUSION: This study confirms that malignant mesothelioma is closely related to asbestos exposure, but not only in main asbestos industrial settings. It suggests that asbestos exposure may take place among prognostic factors of this tumor.     

Pleural malignant mesothelioma and non-occupational exposure to asbestos in Casale Monferrato, Italy.

OBJECTIVES--To assess and quantify the occurrence of pleural malignant mesotheliomas in people who neither experienced occupational exposure to asbestos nor were married to (or known to live with) workers exposed to asbestos in the workplace. The study was conducted in the area of the local health authority of Casale Monferrato, in north western Italy, where a large factory that produced asbestos cement was active up to 1985. No other major activities related to asbestos have ever been present in the area. METHODS--A retrospective survey covering the period 1980 to 1991 identified 126 incident pleural malignant mesotheliomas histologically diagnosed among residents in the local health authority (population at the 1981 census 98,000). Submission of 83 of 95 cases diagnosed during 1980-9 for revision by a panel of five expert pathologists led to the exclusion of 21. The 31 cases diagnosed in 1990-1 were not submitted for revision. For 64 of the 105 retained cases, information derived from different sources (rosters of the employees in the asbestos cement factory dated back to 1907, list of their spouses, clinical records) did not suggest occupational or paraoccupational exposure to asbestos. RESULTS--Incidence excludes cases for which there was some suggestion of occupational or paraoccupational exposure to asbestos. Incidence of histologically confirmed malignant mesothelioma among residents in the local health authority (annual x 100,000; age adjusted) was 4.2 in men and 2.3 in women (based on 26 and 18 cases respectively). In both sexes, rates in 1985-9 were higher than in the previous quinquennium. Corresponding estimates for 1990-1 (based on unrevised diagnoses) suggest similar rates in men and women. CONCLUSION--Rate ratios which are four to six times those measured by conventional Italian cancer registries can hardly be totally explained by bias produced by lack of recognition of occupational or paraoccupational exposure. The problem of proving this type of negative data is common to other circumstances of alleged cancer clusters of environmental (non occupational) origin.     

Pulmonary asbestos and non-asbestos fiber concentrations in autopsied inhabitants in Pohang, Korea

To establish reference values for pulmonary asbestos and non-asbestos fiber concentrations in rural Korean residents, and their comparison with those of urban Korean residents and the Japanese, autopsied lung samples from 22 subjects (20 males and 2 females), in Pohang, without known occupational asbestos exposure histories, were analyzed for asbestos and non-asbestos fibers, using transmission electron microscope equipped with an energy dispersive X-ray analyzer. Chrysotile was the major fiber type found in the lungs of the subjects. The residents in Pohang had significantly lower asbestos and non-asbestos fiber concentrations than the Korean urban residents. The Koreans had significantly lower asbestos and non-asbestos fiber concentrations than the Japanese.     

Five cases of pleural mesothelioma with endemic pleural calcifications in a rural area in Greece.

The authors describe 5 cases of pleural mesothelioma in a rural population of Macedonia, Greece. This population had been covered by an X-ray study over a 3-year period to detect pleural calcifications compatible with asbestos exposure. The study revealed a 24.2% prevalence of pleural plaques among the inhabitants aged over 40 years of 7 rural villages. High contents of asbestos (chrysotile and tremolite)--up to 90% by volume--were found in the material that was used for whitewashing the houses up to 1935. Even now, environmental concentrations of 0.01 fibres/ml were recorded in the houses. The prevalence of pleural mesothelioma in this rural population is high compared to the general population. A possible explanation of the phenomenon may be a cumulative environmental exposure to asbestos which, even though presumably within the acceptable limits for occupational exposure, lasted over a much longer time period, in terms of both daily exposure and total duration.     

Pleuropulmonary lesions, ergotamines and asbestos exposure

OBJECTIVES: This study investigated the possibility of pleuropulmonary lesions, which can occur as rare but serious side effects of different ergot drugs, occurring more commonly in persons earlier exposed to asbestos. METHODS: All reports of pleuropulmonary side effects of the ergot drugs used in Sweden in the Swedish side effect registry from 1985 to 2003 were studied. In addition, the literature was reviewed. RESULTS: In the registry, 47 men and 3 women were found. Of the men, 24 were exposed to asbestos, and 2 denied such exposure; 2 of the 3 women were exposed. In the literature, 111 patients were found--32 had confirmed exposure and 15 denied it. For most of the patients, it was not possible to determine exposure. CONCLUSIONS: Enough evidence exists to postulate that earlier asbestos exposure in combination with the intake of ergot drugs can cause pleuropulmonary lesions.     

Asbestos bodies in a bile duct cancer after occupational exposure

A case of asbestosis after 5 years of occupational asbestos exposure is presented. At the postmortem examination, cholelithiasis and a cancer developing from the cystic duct were found and identified histologically as a squamous cell carcinoma. After digesting the tumor tissue, short asbestos bodies and fragments could be identified having a similar shape as those observed in the lung. The possible role of asbestos in the carcinogenesis of the observed bile duct cancer is proposed. The digestive examination of all malignant tumors of any origin after an asbestos exposure is suggested for the identification of the possible presence of ingested asbestos fibers, and to obtain further comprehensive human pathological data.     

Mesothelioma of the pleura in the Province of Trieste

BACKGROUND: The Province of Trieste, north-eastern Italy (population about 240,000), has been identified as an area with a high incidence of pleural mesothelioma. OBJECTIVES: (i) To obtain preliminary data on the trend of the mesothelioma epidemic in the Province of Trieste during the last six years; (ii) to define the cases in terms of asbestos exposure. METHODS: Pleural mesotheliomas diagnosed at the Department of Surgery, Thoracic Surgery Unit, Trieste University, in the period January 2001-May 2006 were reviewed. The histological diagnosis was generally based on material obtained at thoracoscopy, pleurectomy, or pleuropneumonectomy. In three cases the pathological diagnosis was made by biopsy of the thoracic wall, and in a further three cases by cytological examination ofpleuralfluid. Detailed occupational histories were obtained from the patients themselves at the time of first admission. RESULTS: The group included 99 people resident in the Province of Trieste (89 men and 10 women, aged between 43 and 89 years). On the basis of the occupational history, 95 cases were defined as asbestos-related. A majority ofpatients had been employed in marine work, including shipbuilding (46 cases), port activity (13 cases), and maritime trades (8 cases). Thirteen patients had worked in other industries (iron industry, petrochemical, etc.). Fourteen people had been employed in a variety of occupations (fire-fighter, lift mechanic, cinema projectionist, pastry worker, telephone technician, etc.). Five women had histories of exposure to asbestos at home. About 70% of the patients had their first exposure to asbestos before 1960. Two-thirds of the cases were exposed to asbestos for 20 years or more. Latency periods (time intervals elapsed between first exposure to asbestos and diagnosis of mesothelioma) rangedfrom 25 to 71 years (mean 49.3, median 49.0). One patient had a history ofprior thoracic irradiationfor Hodgkin's disease. CONCLUSIONS: In the Province of Trieste the mesothelioma epidemic does not show any signs of abatement. Besides marine work, a variety of other occupations appear to be associated with the tumour in this area.     

Malignant mesothelioma of the pleura in Trieste, Italy.

One hundred and seventy malignant pleural mesotheliomas seen at necropsy at the Institute of Pathological Anatomy of the Trieste University during the period 1968-1987 were reviewed. The series included 153 men and 17 women, aged between 33 and 92 years (median 70 years). Lifetime work histories were obtained from the patients' relatives by personal or telephone interviews in 162 cases. A majority of the male subjects had been employed in "naval" work, 99 people having worked in the ship-building industry, 19 in the navy and merchant marine, and 7 in docks. A variety of trades appeared in the remaining histories. Work histories were indicative of occupational exposure to asbestos in 150 cases. A further 5 patients with negative or insufficient data showed asbestos bodies in routine lung sections and 5 women had a history of domestic exposure. A majority of the patients had had their first exposure before 1950. The intervals between first exposure and death ranged from 14 to 71 years (median 48 years).     

Pleural mesothelioma after a short interval from first exposure in the wine filter industry

Pleural mesotheliomas are usually reported after a long interval has passed since first exposure to asbestos. We, however, describe a case observed after a latent period of only 7.5 years in a worker exposed in a factory manufacturing auxiliary products for wine treatment, including chrysotile asbestos filters. The exposure to asbestos lasted 3-4 months per year, during which airborne fiber concentrations ranged from 1 to 4 ff/cc in the patient's workplace. Due to the characteristics of the manufacturing process, the asbestos fibers were very thin in diameter. The patient also suffered from nasal breathing impairment. An examination of the literature showed that asbestos-related mesotheliomas have been reported, albeit rarely, after less than 10 years from onset of exposure. Therefore, it is believed that this case should be related to past exposure to asbestos.     

Respiratory health in Turkish asbestos cement workers: the role of environmental exposure

AIM: Benign and malignant pleural and lung diseases due to environmental asbestos exposure constitute an important health problem in Turkey. The country has widespread natural deposits of asbestos in rural parts of central and eastern regions. Few data exists about the respiratory health effects of occupational asbestos exposure in Turkey. A cross-sectional study was conducted to investigate respiratory health effects of occupational asbestos exposure and the contribution of environmental asbestos exposure. METHODS: Investigations included asbestos dust measurements in the workplace and application of an interviewer-administered questionnaire, a standard posteroanterior chest X-ray and spirometry. Information on birthplace of the workers was obtained in 406 workers and used to identify environmental exposure to asbestos, through a map of geographic locations with known asbestos exposure. RESULTS: Asbestos dust concentration in the ambient air of the work sites (fiber/ml) ranged between 0.2 and 0.76 (mean: 0.25, median: 0.22). Environmental exposure to asbestos was determined in 24.4% of the workers. After the adjustment for age, smoking, occupational asbestos exposure, and potential risk factors environmental asbestos exposure was associated with small irregular opacities grade > or = 1/0 (44.2% vs. 26.6%, P < 0.01), FVC% (97.8 vs. 104.5, P < 0.0001), and FEV1% (92.4 vs. 99.9, P < .0001). Occupational exposure to asbestos was associated with small irregular opacities grade > or = 1/0 (OR: 2.0, 95% CI: 1.3-3.1, per 1 unit increase in the natural logarithm of fiber/ml) and FEV1/FVC% (beta: 1.1, SEM: 0.54; P < 0.05, per 1 unit increase in the natural logarithm of fiber/ml). CONCLUSIONS: Environmental exposure to asbestos could increase the risk of asbestosis and lung function impairment in workers occupationally exposed to asbestos, independent from occupational exposure and smoking.     

Cohort mortality study of women compensated for asbestosis in Italy.

BACKGROUND: The carcinogenic effect of asbestos is accepted for lung cancer and mesothelioma, while conflicting opinions exist for other cancer sites. The aim of the present investigation is to study cause-specific mortality of women compensated for asbestosis who had certainly been exposed to high levels of asbestos fibers. METHODS: The cause-specific mortality of all Italian women compensated for asbestosis and alive December 31, 1979, was investigated through October 30, 1997. In the total cohort, which included 631 subjects, 277 deaths occurred. Cause-specific SMRs (Standardized Mortality Ratio) were computed using the national rates for comparison. RESULTS: A significantly increased mortality for all diseases related to asbestos exposure was observed. Mortality for all causes, all neoplasms, lung cancer, uterine cancer, ovarian cancer, and non-neoplastic respiratory diseases was significantly increased. Separate analyses for textile (n = 276) and asbestos-cement (n = 278) workers were performed. Women employed in the textile industry, mainly exposed to chrysotile, who are compensated at a younger age, showed higher SMRs for lung cancer and asbestosis. Women in the asbestos-cement industry, mainly exposed to crocidolite containing asbestos mixtures, experienced higher mortality for pleural malignancies. CONCLUSIONS: The role of asbestos exposure in the development of gastrointestinal and genital neoplasms is discussed.