American Family Physician, Jan 15, 2000 by Barbara Apgar
Not only has the prevalence of malignant pleural mesothelioma (MPM) increased over the past 40 years, it is anticipated that the increase will continue because of the widespread use of asbestos from the 1940s to the end of the 1970s. MPM is a highly lethal neoplasm, and diagnosis is difficult because of the frequency of vague symptoms present over a long period of time. Chest radiography and computed tomographic (CT) scans can be helpful only in revealing the presence of pleural effusion. Enthusiasm for the use of pleural biopsy has waned, and other procedures such as percutaneous needle biopsy, fluoroscopy and CT biopsy have significant limitations. Heilo and associates assessed the clinical use of ultrasonographically (US)-guided core-needle biopsy performed with a one-hand automatic sampling technique in the diagnosis of MPM.
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This retrospective study included 70 patients admitted to a single hospital over a 10-year period with a tentative diagnosis of MPM. All study participants underwent US-guided core-needle biopsy; punctures were made under local anesthesia. Automatic high-speed core biopsy equipment used different-sized needle-gun combinations. One to five needle punctures were made in 82 procedures.
Of the 70 patients, first-attempt biopsy facilitated the diagnosis of MPM in 40 patients and the diagnosis of other diseases in 16 patients. The US-guided core-needle biopsy had an accuracy rate in the detection of MPM of 80 percent, a positive predictive value of 100 percent and a negative predictive value of 57 percent. In two patients with MPM, the diagnosis was not 100 percent conclusive, but the histologic specimens showed a sarcomatous-type MPM. These patients were treated for MPM without further investigation.
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In 14 patients, the biopsy specimen was inadequate. Twelve had MPM; two had another disease. Six patients did not undergo additional procedures but were treated for MPM based on prior biopsy. Eight patients underwent repeat procedures and in six of these patients, the correct diagnosis was determined. One of the two patients who did not have a conclusive diagnosis underwent surgical biopsy and was found to have MPM. The other patient underwent treatment for MPM based on clinical presentation.
No significant differences in diagnostic accuracy between the various needle-gun combinations was evident. Two minor complications occurred- mild hemoptysis and local chest pain that resolved within an hour. No skin metastases developed at the biopsy needle entry site over the study period.
Results of the study demonstrated that the US needle guidance technique is a quick and safe procedure. With US guidance, focal tumors and diffuse pleural thickening can be localized, regardless of the presence of pleural fluid, and biopsy can be performed.
The authors conclude that the best results are obtained when the biopsy is performed in the lateral costophrenic angle. Because of the presence of fluid in the pleural cavity in this region, the procedure is technically easier in this location. Tumor seeding or direct tumor growth through the chest wall is not evident with US-guided biopsy but is a potential complication of the other procedures used to obtain pleural biopsy specimens. Although surgically and thoracoscopically- guided biopsies have a higher accuracy rate than US-guided biopsy, the ease and low complication rate of US-guided tissue sampling offers an alternative choice for diagnosing MPM. As the US-guided technique is performed more frequently, accuracy will most likely improve.
Heilo A, et al. Malignant pleural mesothelioma: US-guided histologic core-needle biopsy. Radiology June 1999;211:657-9.
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COPYRIGHT 2000 Gale Group
Monday, June 11, 2007
Can Exposure to Very Low Levels of Asbestos Induce Pleural Mesothelioma?
American Journal of Respiratory and Critical Care Medicine, Oct 15, 2005 by Goldberg, Marcel, Luce, Danièle
Asbestos is a recognized human carcinogen, causally related to pleural and peritoneal mesothelioma and to lung cancer (1). Mesothelioma is of particular interest, as it is a specific outcome of asbestos exposure and no other causal factor except for exposure to asbestos (and erionite, a naturally occurring mineral fiber found in Turkey) (2) has been established or even convincingly suspected.
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The vast majority of asbestos-induced mesotheliomas in the industrialized world is caused by occupational asbestos exposure, and occurs among workers engaged in extracting and manufacturing asbestos, or performing tasks involving contact with asbestos-containing materials (3). Concern used to be focused on the occupational environment, but it is now recognized that asbestos fibers are widely distributed in the general environment. Persons can be exposed to asbestos in different nonoccupational circumstances: living with asbestos workers, with regular exposure to soiled work clothes brought home; environmental exposure in the neighborhood of industrial sources (asbestos mines and mills, asbestos processing plants); passive exposure in buildings containing asbestos; and natural environmental exposure to geological sources (4).
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Studying the effects of nonoccupational asbestos exposure on mesothelioma risk is important because it could provide information about the nature of the exposure-response relationship that cannot be obtained from studies of workers whose exposures begin in adulthood, are limited to working hours, are typically much higher in concentration, and who are mainly male. Natural environmental exposure to geological sources is of special interest, since populations subjected to natural sources present specific temporal exposure characteristics: exposure can start during childhood and be lifelong, and it can occur around the clock, seven days a week. Evidence on environmental exposure of natural origin thus provides information about the effect of early exposure on cancer risk and on latency periods, susceptibility according to sex, or the potentially different effect of asbestos fiber types (chrysotile, or amphiboles such as crocidolite, amosite, or tremolite, which are considered to be more potent carcinogens for mesothelioma than chrysotile fibers).
The main findings of studies in rural areas of Turkey (5), Greece (6), some Mediterranean islands (7-9), China (10), and New Caledonia (11), where occupational exposure to asbestos is rare, even nonexistent, show that asbestos exposure starting at birth does not seem to influence the latency period of mesothelioma. The data also indicate that susceptibility does not differ according to sex, and confirm that the much higher rates of mesothelioma among males in the industrialized countries are most probably due to sex differences in occupational exposure to asbestos.
Studies of mesothelioma related to environmental exposure to geological sources of asbestos have yielded important findings. However, some important issues remain unresolved. Thus, it would be of utmost importance, from a scientific and public health point of view, to know whether exposure to low levels of asbestos is able to induce pleural mesothelioma. There is still controversy regarding this question (12, 13). While exposure in environmental settings is generally much lower than in occupational circumstances, the levels may not be negligible. In studies in which elevated risk of mesothelioma was demonstrated, people typically lived in close vicinity of naturally occurring asbestos sources, and may have had direct contact with asbestos, when whitewashing houses with material containing asbestos or working in polluted fields. It is thus likely that lifelong cumulative exposure may have been as high (if not higher) as in some occupational settings, but it was not - or not adequately - measured, and nonoccupational studies have not yet provided adequate answers.
This is why the work of Pan and coworkers, reported in this issue of the Journal (pages 1019-1025) (14), showing a relationship between mesothelioma risk and residential distance from naturally occurring asbestos, and suggesting that there is an excess risk of mesothelioma even at a long distance from the asbestos source, is important. To our knowledge, this study is the first one that demonstrates such an effect quite convincingly.
While this study has some limitations (occupational exposure was only partially taken into account, no residential history was available for the subjects, no cases under 35 years of age could be included, and asbestos exposure was indirectly assessed), many features are strong. It relied on a register-based selection of a very large number of mesothelioma cases, and their localization was quite precise, thanks to the geocoding of residency and to the use of advanced GIS techniques. The results show a convincing internal consistency. The role of occupational exposure is clear and the risk varies with exposure, showing that even if it was not completely controlled for, the study captures its main effect. There was a linear relationship between distance and the pleural mesothelioma risk, still evident when different methods were used or when restricted to some subgroups; the distance-effect relationship was similar among men and women, even if not statistically significant among the latter due to smaller numbers
Asbestos is a recognized human carcinogen, causally related to pleural and peritoneal mesothelioma and to lung cancer (1). Mesothelioma is of particular interest, as it is a specific outcome of asbestos exposure and no other causal factor except for exposure to asbestos (and erionite, a naturally occurring mineral fiber found in Turkey) (2) has been established or even convincingly suspected.
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The vast majority of asbestos-induced mesotheliomas in the industrialized world is caused by occupational asbestos exposure, and occurs among workers engaged in extracting and manufacturing asbestos, or performing tasks involving contact with asbestos-containing materials (3). Concern used to be focused on the occupational environment, but it is now recognized that asbestos fibers are widely distributed in the general environment. Persons can be exposed to asbestos in different nonoccupational circumstances: living with asbestos workers, with regular exposure to soiled work clothes brought home; environmental exposure in the neighborhood of industrial sources (asbestos mines and mills, asbestos processing plants); passive exposure in buildings containing asbestos; and natural environmental exposure to geological sources (4).
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Studying the effects of nonoccupational asbestos exposure on mesothelioma risk is important because it could provide information about the nature of the exposure-response relationship that cannot be obtained from studies of workers whose exposures begin in adulthood, are limited to working hours, are typically much higher in concentration, and who are mainly male. Natural environmental exposure to geological sources is of special interest, since populations subjected to natural sources present specific temporal exposure characteristics: exposure can start during childhood and be lifelong, and it can occur around the clock, seven days a week. Evidence on environmental exposure of natural origin thus provides information about the effect of early exposure on cancer risk and on latency periods, susceptibility according to sex, or the potentially different effect of asbestos fiber types (chrysotile, or amphiboles such as crocidolite, amosite, or tremolite, which are considered to be more potent carcinogens for mesothelioma than chrysotile fibers).
The main findings of studies in rural areas of Turkey (5), Greece (6), some Mediterranean islands (7-9), China (10), and New Caledonia (11), where occupational exposure to asbestos is rare, even nonexistent, show that asbestos exposure starting at birth does not seem to influence the latency period of mesothelioma. The data also indicate that susceptibility does not differ according to sex, and confirm that the much higher rates of mesothelioma among males in the industrialized countries are most probably due to sex differences in occupational exposure to asbestos.
Studies of mesothelioma related to environmental exposure to geological sources of asbestos have yielded important findings. However, some important issues remain unresolved. Thus, it would be of utmost importance, from a scientific and public health point of view, to know whether exposure to low levels of asbestos is able to induce pleural mesothelioma. There is still controversy regarding this question (12, 13). While exposure in environmental settings is generally much lower than in occupational circumstances, the levels may not be negligible. In studies in which elevated risk of mesothelioma was demonstrated, people typically lived in close vicinity of naturally occurring asbestos sources, and may have had direct contact with asbestos, when whitewashing houses with material containing asbestos or working in polluted fields. It is thus likely that lifelong cumulative exposure may have been as high (if not higher) as in some occupational settings, but it was not - or not adequately - measured, and nonoccupational studies have not yet provided adequate answers.
This is why the work of Pan and coworkers, reported in this issue of the Journal (pages 1019-1025) (14), showing a relationship between mesothelioma risk and residential distance from naturally occurring asbestos, and suggesting that there is an excess risk of mesothelioma even at a long distance from the asbestos source, is important. To our knowledge, this study is the first one that demonstrates such an effect quite convincingly.
While this study has some limitations (occupational exposure was only partially taken into account, no residential history was available for the subjects, no cases under 35 years of age could be included, and asbestos exposure was indirectly assessed), many features are strong. It relied on a register-based selection of a very large number of mesothelioma cases, and their localization was quite precise, thanks to the geocoding of residency and to the use of advanced GIS techniques. The results show a convincing internal consistency. The role of occupational exposure is clear and the risk varies with exposure, showing that even if it was not completely controlled for, the study captures its main effect. There was a linear relationship between distance and the pleural mesothelioma risk, still evident when different methods were used or when restricted to some subgroups; the distance-effect relationship was similar among men and women, even if not statistically significant among the latter due to smaller numbers
Synchronous Pulmonary Carcinoma and Pleural Diffuse Malignant Mesothelioma
Synchronous Pulmonary Carcinoma and Pleural Diffuse Malignant Mesothelioma
Archives of Pathology & Laboratory Medicine, May 2006 by Allen, Timothy Craig, Moran, Cesar
* Synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma is rare. Cases from the archives of 2 large referral centers were reviewed to identify cases of synchronously occurring pulmonary carcinoma and pleural diffuse malignant mesothelioma. Three cases of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma were identified from more than 16 000 pleuropulmonary cases and were reviewed for demographic, clinical, radiographie, histologie, and immunohistochemical findings. The patients were men who were 63, 67, and 77 years old. Two had positive smoking histories; the smoking history of the other patient is unknown. One patient had a positive history of asbestos exposure; one patient had no history of asbestos exposure; and one patient's history of asbestos exposure is unknown. The patients underwent surgery for treatment of adenocarcinoma that was diagnosed preoperatively. Two of the adenocarcinomas were of a predominantly bronchioloalveolar pattern. No diffuse malignant mesothelioma was identified preoperatively. Diffuse malignant mesothelioma was suspected on the basis of pleural involvement by tumor with histology differing from that of the adenocarcinoma. Tumor immunostaining supported the diagnoses. The average survival after diagnosis was 6 weeks or less. In summary, the paucity of cases at 2 large referral centers and the paucity of cases reported in the English language literature highlights the rarity of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma. These synchronous neoplasms occur in patients who have risk factors for both neoplasms independently. Length of survival following diagnosis is bleak.
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(Arch Pathol Lab Med. 2006;130:721-724)
The simultaneous occurrence of multiple primary pleuropulmonary malignancies is rare, and although simultaneous primary pleuropulmonary malignancies have been reported in patients with significant occupational exposure to asbestos,1-4 only 14 cases of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma have been reported in the English language literature.5-10 Table 1 shows findings regarding the 14 previously reported cases. We present 3 cases identified from the archives of 2 large referral centers, and review these cases to identify any characteristic features or diagnostic problems.
MATERIALS AND METHODS
We reviewed cases from the archives of 2 large referral centers: Baylor College of Medicine for the past 25 years and M. D. Anderson Hospital for the past 10 years. We identified 3 cases (approximately 0.019%) of synchronously occurring pulmonary carcinoma and pleural diffuse malignant mesothelioma from among more than 16000 archived pleuropulmonary cases. One case had been previously reported,7 Criteria for inclusion required the concurrent occurrence of primary pulmonary carcinoma and pleural diffuse malignant mesothelioma. All other metastatic neoplasms to the pleura were excluded. cases were reviewed for demographic, clinical, and radiographic findings as well as histologic and immunohistochemical findings. Tables 2 and 3 show the demographic and immunohistochemical findings, respectively. The criteria used to diagnose primary pulmonary carcinoma and pleural diffuse malignant mesothelioma are those that have been previously published.11,12
PATHOLOGIC FINDINGS
The patients were men aged 63, 67, and 77 years. Patients 1 and 2 had smoking histories; the smoking history of patient 3 is unknown. Patient 1 worked as an insulator and was found to have asbestosis. Patient 2 had no significant history of asbestos exposure. No information is available regarding asbestos exposure for patient 3. For all patients, survival after diagnosis was 6 weeks or less.
Radiographically, diffuse malignant mesothelioma was suspected in these patients on the basis of pleural effusions and pleural involvement by tumor. All 3 patients had pleural effusions and were suspected of having a pleural malignancy. Patients 1 and 3 had preoperative diagnoses of adenocarcinomas with a predominantly bronchioloalveolar pattern. Patient 1 had a right pleural effusion and consolidation of the right lower lobe, and was found to have a 1-cm adenocarcinoma with a predominantly bronchioloalveolar pattern. Patient 2 was found to have advanced-stage lung adenocarcinoma, arising in the right upper lobe and extending into subpleural adipose tissue; he was treated with chemotherapy. Information regarding specific site and size of tumor for patient 3 was not available. No patient had a tissue diagnosis of diffuse malignant mesothelioma prior to surgery; diffuse malignant mesothelioma was found in patient 2 at autopsy.
Patient 1 was found to have epithelial diffuse malignant mesothelioma, measuring approximately 14 cm in greatest dimension, involving the right pleura. Patient 2 was found to have biphasic diffuse malignant mesothelioma involving the left pleura and left upper lobe, with extension into the chest wall. Patient 3 was found to have biphasic diffuse malignant mesothelioma. Information regarding specific site and size of the tumor is not available. Histologically, the epithelial diffuse malignant mesothelioma showed epithelioid cells arranged in sheets and cords, with acinar structures present in some areas. Tumor necrosis was focally present. Desmoplastic reaction surrounded nests of adenocarcinoma in some areas. The 2 biphasic diffuse malignant mesotheliomas contained an epithelial component with features as described, as well as a spindle cell component arranged predominantly in sheets. Some areas of necrosis were present within the sheets of spindle cells (Figures 1 through 4).
Archives of Pathology & Laboratory Medicine, May 2006 by Allen, Timothy Craig, Moran, Cesar
* Synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma is rare. Cases from the archives of 2 large referral centers were reviewed to identify cases of synchronously occurring pulmonary carcinoma and pleural diffuse malignant mesothelioma. Three cases of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma were identified from more than 16 000 pleuropulmonary cases and were reviewed for demographic, clinical, radiographie, histologie, and immunohistochemical findings. The patients were men who were 63, 67, and 77 years old. Two had positive smoking histories; the smoking history of the other patient is unknown. One patient had a positive history of asbestos exposure; one patient had no history of asbestos exposure; and one patient's history of asbestos exposure is unknown. The patients underwent surgery for treatment of adenocarcinoma that was diagnosed preoperatively. Two of the adenocarcinomas were of a predominantly bronchioloalveolar pattern. No diffuse malignant mesothelioma was identified preoperatively. Diffuse malignant mesothelioma was suspected on the basis of pleural involvement by tumor with histology differing from that of the adenocarcinoma. Tumor immunostaining supported the diagnoses. The average survival after diagnosis was 6 weeks or less. In summary, the paucity of cases at 2 large referral centers and the paucity of cases reported in the English language literature highlights the rarity of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma. These synchronous neoplasms occur in patients who have risk factors for both neoplasms independently. Length of survival following diagnosis is bleak.
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(Arch Pathol Lab Med. 2006;130:721-724)
The simultaneous occurrence of multiple primary pleuropulmonary malignancies is rare, and although simultaneous primary pleuropulmonary malignancies have been reported in patients with significant occupational exposure to asbestos,1-4 only 14 cases of synchronous pulmonary carcinoma and pleural diffuse malignant mesothelioma have been reported in the English language literature.5-10 Table 1 shows findings regarding the 14 previously reported cases. We present 3 cases identified from the archives of 2 large referral centers, and review these cases to identify any characteristic features or diagnostic problems.
MATERIALS AND METHODS
We reviewed cases from the archives of 2 large referral centers: Baylor College of Medicine for the past 25 years and M. D. Anderson Hospital for the past 10 years. We identified 3 cases (approximately 0.019%) of synchronously occurring pulmonary carcinoma and pleural diffuse malignant mesothelioma from among more than 16000 archived pleuropulmonary cases. One case had been previously reported,7 Criteria for inclusion required the concurrent occurrence of primary pulmonary carcinoma and pleural diffuse malignant mesothelioma. All other metastatic neoplasms to the pleura were excluded. cases were reviewed for demographic, clinical, and radiographic findings as well as histologic and immunohistochemical findings. Tables 2 and 3 show the demographic and immunohistochemical findings, respectively. The criteria used to diagnose primary pulmonary carcinoma and pleural diffuse malignant mesothelioma are those that have been previously published.11,12
PATHOLOGIC FINDINGS
The patients were men aged 63, 67, and 77 years. Patients 1 and 2 had smoking histories; the smoking history of patient 3 is unknown. Patient 1 worked as an insulator and was found to have asbestosis. Patient 2 had no significant history of asbestos exposure. No information is available regarding asbestos exposure for patient 3. For all patients, survival after diagnosis was 6 weeks or less.
Radiographically, diffuse malignant mesothelioma was suspected in these patients on the basis of pleural effusions and pleural involvement by tumor. All 3 patients had pleural effusions and were suspected of having a pleural malignancy. Patients 1 and 3 had preoperative diagnoses of adenocarcinomas with a predominantly bronchioloalveolar pattern. Patient 1 had a right pleural effusion and consolidation of the right lower lobe, and was found to have a 1-cm adenocarcinoma with a predominantly bronchioloalveolar pattern. Patient 2 was found to have advanced-stage lung adenocarcinoma, arising in the right upper lobe and extending into subpleural adipose tissue; he was treated with chemotherapy. Information regarding specific site and size of tumor for patient 3 was not available. No patient had a tissue diagnosis of diffuse malignant mesothelioma prior to surgery; diffuse malignant mesothelioma was found in patient 2 at autopsy.
Patient 1 was found to have epithelial diffuse malignant mesothelioma, measuring approximately 14 cm in greatest dimension, involving the right pleura. Patient 2 was found to have biphasic diffuse malignant mesothelioma involving the left pleura and left upper lobe, with extension into the chest wall. Patient 3 was found to have biphasic diffuse malignant mesothelioma. Information regarding specific site and size of the tumor is not available. Histologically, the epithelial diffuse malignant mesothelioma showed epithelioid cells arranged in sheets and cords, with acinar structures present in some areas. Tumor necrosis was focally present. Desmoplastic reaction surrounded nests of adenocarcinoma in some areas. The 2 biphasic diffuse malignant mesotheliomas contained an epithelial component with features as described, as well as a spindle cell component arranged predominantly in sheets. Some areas of necrosis were present within the sheets of spindle cells (Figures 1 through 4).
Pleural mesothelioma cases in Biancavilla are related to a new fluoro-edenite fibrous amphibole
Archives of Environmental Health, April, 2003 by Pietro Comba, Antonio Gianfagna, Luigi Paoletti
FLUORO-EDENITE is a new mineral species detected in Biancavilla, a city in eastern Sicily, Italy, characterized by a high incidence of pleural mesothelioma. In this study, we sought to provide new information about this fibrous amphibole and to discuss epidemiologic and environmental evidence supporting the etiologic role of fluoro-edenite in the occurrence of mesothelioma.
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In a national survey of mortality from pleura mesothelioma in Italy from 1988 to 1992, a cluster of cases (N = 4) was detected in Biancavilla (standardized mortality ratio [SMR] = 417 [95% confidence interval {CI} = 142,954]). (1) From 1993 to 1997, an additional 8 cases were observed (SMR = 721 [95% CI = 359, 1,300]). (2)These findings prompted an ad hoc epidemiological investigation. Paoletti et al. (3) reported that 17 cases were identified and reviewed, their pathological diagnoses were confirmed, and history of exposures to asbestos was evaluated. Information on both occupational exposures and exposures to asbestos in the work place (in-site exposure) was available for 16 subjects There was no evidence of exposure for 9 subjects; 2 had probable exposure (a construction worker and a foundry worker). Exposure could neither be ascertained nor ruled out for the remaining 5 subjects, who worked in bricklaying, printing, or the clothing and paper industries.
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Given that the occupational histories did not point to a common activity or source of exposure that could significantly increase the subjects' risk for developing mesothelioma, a general environmental source was considered. An environmental survey suggested that the general environmental source might be asbestos from the stone quarries located in Monte Calvario, southeast of the town. The materials extracted from the quarries--used widely in the local building industry--contained large quantities of fibrous amphiboles.
The Monte Calvario amphiboles were initially referred to by Paoletti et al. (3) as sodium (Na)--and fluorine (F)-rich tremolites and actinolites. The fibers were detected in the materials extracted from the quarries and in the plaster or mortar of the buildings in Biancavilla. The same fibers were detected in a lung tissue sample taken at autopsy from an 86-yr-old woman who resided in Biancavilla prior to succumbing to pleural mesothelioma. Other mineral fibers were not found in the sample, and it was impossible to reveal the presence of ferruginous bodies. Inasmuch as the quantity of the specimen was very limited, it was impossible to conduct histological investigations, the purpose of which was the elucidation of pathological changes related to an exposure to asbestos. No lung tissue samples were available from the other identified cases.
A subsequent crystal-chemistry investigation of the Monte Calvario amphiboles (4) identified the mineral as fluoro-edenite--a new end-member of the edenite [right arrow] fluoro-edenite series. The finding was confirmed by the Commission on New Minerals and Mineral Names on January 30, 2001. (5)
Environmental and Geological Investigations
The fluoro-edenite from Biancavilla (ideal formula: Na[Ca.sub.2][Mg.sub.5][Si.sub.7]Al[O.sub.22][F.sub.2]) is transparent, intense yellow with habit from prismatic to acicular. It is also fibrous and asbestiform, occurring in autoclasts of grey-red altered benmoreitic lavas where it is generally associated with potassium-feldspar and plagioclase, quartz, clino-and orthopyroxenes, fluoro-apatite, ilmenite, and hematite. In Table 1 are shown relevant mineralogical data for fluoro-edenite.
In the Monte Calvario area, the fluoro-edenite mineralization process yielded mainly prismatic, evenly sized acicular crystals (Fig. 1). Similar fibers have recently been found in neighboring areas of the quarry (Fig. 2), but in a different volcanic formation. The fibers are similar in size and morphology to some amphibolic asbestos fibers (tremolite, actinolite, antophyllite); sometimes they occur as elastic and tensile (filamentous) fibers (Fig. 2) (size: < 0.5 [micro]m in width to > 10 [micro]m in length).
[FIGURES 1-2 OMITTED]
The fluoro-edenite at Monte Calvario is found in cavities and cracks of benmoreitic lava that has been meta-somatized by hot, F-rich fluids. The asbestiform fluoro-edenite is found in refall pyroclastic products and scoriae that have been greatly altered; these are mainly found in the northwest of Monte Calvario. The finding of amphibolic fibers near Monte Calvario points to a very complex volcanic process with several evolutionary stages. It also suggests that the process may have also occurred in other areas that have not yet been identified, perhaps because the products are not at the surface or perhaps they have not yet been quarried.
Discussion and Conclusions
The physical processes that determined the genesis of this new amphibole are not yet understood. Among the various hypotheses posited, the most plausible points to an upsurge of very hot fluids directly from the magma chamber. These fluids altered and metasomatized the previously emplaced volcanic products (lavas, pyroclasts). Fluoro-edenite appears to have formed during this metasomatic process because there was an abundance of fluorine in the contaminating fluid. Concurrently, the rising fluid also conditioned other nionlavic formations peripheral to Mount Calvario and gave rise to asbestiform fluoro-edenite. The different morphology of the fibers may be ascribed to different rates of cooling of the materials affected: larger fluoro-edenite crystals in the central part of the dome represent a slower cooling rate, whereas asbestiform fibers in the more peripheral areas represent a faster cooling rate.
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FLUORO-EDENITE is a new mineral species detected in Biancavilla, a city in eastern Sicily, Italy, characterized by a high incidence of pleural mesothelioma. In this study, we sought to provide new information about this fibrous amphibole and to discuss epidemiologic and environmental evidence supporting the etiologic role of fluoro-edenite in the occurrence of mesothelioma.
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* Unusually High Incidence of...
* Malignant pleural mesothelioma...
* Metastatic malignant pleural...
* Incidence of pleural...
Most Popular Articles
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In a national survey of mortality from pleura mesothelioma in Italy from 1988 to 1992, a cluster of cases (N = 4) was detected in Biancavilla (standardized mortality ratio [SMR] = 417 [95% confidence interval {CI} = 142,954]). (1) From 1993 to 1997, an additional 8 cases were observed (SMR = 721 [95% CI = 359, 1,300]). (2)These findings prompted an ad hoc epidemiological investigation. Paoletti et al. (3) reported that 17 cases were identified and reviewed, their pathological diagnoses were confirmed, and history of exposures to asbestos was evaluated. Information on both occupational exposures and exposures to asbestos in the work place (in-site exposure) was available for 16 subjects There was no evidence of exposure for 9 subjects; 2 had probable exposure (a construction worker and a foundry worker). Exposure could neither be ascertained nor ruled out for the remaining 5 subjects, who worked in bricklaying, printing, or the clothing and paper industries.
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Given that the occupational histories did not point to a common activity or source of exposure that could significantly increase the subjects' risk for developing mesothelioma, a general environmental source was considered. An environmental survey suggested that the general environmental source might be asbestos from the stone quarries located in Monte Calvario, southeast of the town. The materials extracted from the quarries--used widely in the local building industry--contained large quantities of fibrous amphiboles.
The Monte Calvario amphiboles were initially referred to by Paoletti et al. (3) as sodium (Na)--and fluorine (F)-rich tremolites and actinolites. The fibers were detected in the materials extracted from the quarries and in the plaster or mortar of the buildings in Biancavilla. The same fibers were detected in a lung tissue sample taken at autopsy from an 86-yr-old woman who resided in Biancavilla prior to succumbing to pleural mesothelioma. Other mineral fibers were not found in the sample, and it was impossible to reveal the presence of ferruginous bodies. Inasmuch as the quantity of the specimen was very limited, it was impossible to conduct histological investigations, the purpose of which was the elucidation of pathological changes related to an exposure to asbestos. No lung tissue samples were available from the other identified cases.
A subsequent crystal-chemistry investigation of the Monte Calvario amphiboles (4) identified the mineral as fluoro-edenite--a new end-member of the edenite [right arrow] fluoro-edenite series. The finding was confirmed by the Commission on New Minerals and Mineral Names on January 30, 2001. (5)
Environmental and Geological Investigations
The fluoro-edenite from Biancavilla (ideal formula: Na[Ca.sub.2][Mg.sub.5][Si.sub.7]Al[O.sub.22][F.sub.2]) is transparent, intense yellow with habit from prismatic to acicular. It is also fibrous and asbestiform, occurring in autoclasts of grey-red altered benmoreitic lavas where it is generally associated with potassium-feldspar and plagioclase, quartz, clino-and orthopyroxenes, fluoro-apatite, ilmenite, and hematite. In Table 1 are shown relevant mineralogical data for fluoro-edenite.
In the Monte Calvario area, the fluoro-edenite mineralization process yielded mainly prismatic, evenly sized acicular crystals (Fig. 1). Similar fibers have recently been found in neighboring areas of the quarry (Fig. 2), but in a different volcanic formation. The fibers are similar in size and morphology to some amphibolic asbestos fibers (tremolite, actinolite, antophyllite); sometimes they occur as elastic and tensile (filamentous) fibers (Fig. 2) (size: < 0.5 [micro]m in width to > 10 [micro]m in length).
[FIGURES 1-2 OMITTED]
The fluoro-edenite at Monte Calvario is found in cavities and cracks of benmoreitic lava that has been meta-somatized by hot, F-rich fluids. The asbestiform fluoro-edenite is found in refall pyroclastic products and scoriae that have been greatly altered; these are mainly found in the northwest of Monte Calvario. The finding of amphibolic fibers near Monte Calvario points to a very complex volcanic process with several evolutionary stages. It also suggests that the process may have also occurred in other areas that have not yet been identified, perhaps because the products are not at the surface or perhaps they have not yet been quarried.
Discussion and Conclusions
The physical processes that determined the genesis of this new amphibole are not yet understood. Among the various hypotheses posited, the most plausible points to an upsurge of very hot fluids directly from the magma chamber. These fluids altered and metasomatized the previously emplaced volcanic products (lavas, pyroclasts). Fluoro-edenite appears to have formed during this metasomatic process because there was an abundance of fluorine in the contaminating fluid. Concurrently, the rising fluid also conditioned other nionlavic formations peripheral to Mount Calvario and gave rise to asbestiform fluoro-edenite. The different morphology of the fibers may be ascribed to different rates of cooling of the materials affected: larger fluoro-edenite crystals in the central part of the dome represent a slower cooling rate, whereas asbestiform fibers in the more peripheral areas represent a faster cooling rate.
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Incidence of pleural mesothelioma in New Caledonia: a 10-year survey - 1978-1987
Incidence of pleural mesothelioma in New Caledonia: a 10-year survey - 1978-1987
Archives of Environmental Health, Sept-Oct, 1991 by Paquerette Goldberg, Marcel Goldberg, Marie-Josee Marne, Albert Hirsch, Jean Tredaniel
ASBESTOS, in various forms, is a well-known risk factor for certain diseases. Pleural cancer is related to occupational exposure [1,2] (asbestos or fibers of industrial origin) and environmental exposure (e.g., natural fibers in the soil of a region, local industries that use certain materials, asbestos in building materials). [3-5] Persons who live with an occupationally exposed member of the household can also experience exposure. [6]
Related Results
* Unusually High Incidence of...
* Malignant pleural mesothelioma...
* Metastatic malignant pleural...
* Pleural mesothelioma cases in...
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in Health
* Cocktails and...
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Within the framework of a study on the relationship between respiratory cancer and occupational exposure in the nickel industry, we collected data on all respiratory cancer cases, including cancer of the pleura, that were diagnosed during a 10-y period (i.e., 1978-1987). In an incidence study and in a case-control study within a cohort of nickel-exposed workers, [7] nickel exposure was excluded in New Caledonia as a risk-factor of respiratory cancer, including, as expected, cancer of the pleura.
The authors considered the possible pathological role of natural asbestos fibers in the soil, especially in the nickel mines, [8,9] to be of sufficient interest to warrant study.
Materials and methods
New Caledonia is a large island in the Southern Pacific region. Of the approximately 145 000 inhabitants, 40% are Melanesian and 40% are European.
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All pleural cancer cases that were diagnosed during the preceding 10-y period were reviewed in France by a Certification Committee that was composed of pneumology experts. The cases were then submitted for certification to the French National Committee of Mesothelioma. Twelve cases were certified as primitive pleural cancers, of which 9 were mesothelioma cases. The remaining 3 were probable cases, but clinico-pathological evidence was insufficient. The characteristics of the cases are shown in Table 1.
Residence and occupational history information for the 12 cases was reconstructed during an interview with a family member. Information included details on [TABULAR DATA OMITTED]
all places of residence (name of the town or village, years of arrival and departure) and a description of all employment activities (i.e., type of work and dates of employment that were related to occupational exposure, if any).
The incidence of pleural cancer in New Caledonia was compared with five reference cancer registers that were representative of (a) different levels of industrialization; (b) the Anglo-Saxon and French lifestyles; and (c) various regions of the world, including the Pacific. Standardized Incidence Ratios (SIRs) were calculated by indirect standardization and were based on the age structure of the population. The observed number of cases was compared with the number expected (Poisson).
Results
The comparisons between cases in New Calendonia and the 5 reference registers are presented in Table 2. In all instances, the observed number of cases of pleural cancer in New Calendonia was higher than expected. The differences were statistically significant for the population as a whole and also for Melanesians.
The excess of pleural cancer cases was low compared with the results of other observations in nonoccupationally exposed populations, [10] and it could be related to an environmental or occupational factor. Identification of a possible cause for this excess in New Caledonia was investigated, and residential and occupational histories of the 12 cases were examined.
The interviews revealed that all 12 patients had lived at least part of their lives in rural areas (i.e., the bush). Other characteristics that were related to residence were extremely variable (Fig. 1). Some patients had always resided in the bush in the same region (i.e., Hienghene region, case no. 5; Kouaoua region, case no. 9; Moindou region, case no. 11; Bourail region, case no. 7). With the exception of a stay at Paita, case no. 2 had always lived on Lifou island. Case no. 12 resided in the bush for the shortest period of time (i.e., 2 y in the village of Yate).
Only two cases lived primarily in Noumea, which is the largest city (Fig. 1). One-half of the total population of New Caledonia lives in Noumea. The two cases were 58 and 61 y of age at the time of diagnosis. However, the youngest cases (31, 35, and 40 y of age at diagnosis) lived primarily in the central region between Poya and Canala.
Occupational histories varied. Three patients worked in the nickel industry: case no. 4 was an engine driver at a mine for 6 y, case no. 10 was a bargeman for 9 y, and case no. 12 was a clerk in a mine for 1 y. Other cases had work connections with mines, either personally (e.g., transportation of ore by truck) or through their families (e.g., father, brother, husband). Only 3 cases (nos. 2, 3, and 5) did not mention contact with mining.
The 3 women who had mesothelioma (cases no. 7, 8 and 9) were Melanesians, and except for case no. 7 who had lived in the small town of Bourail for 6 y, they had always lived in a tribe (traditional residence). These 3 women maintained traditional occupations, and case no. 7 had been a cook while she lived in Bourail. Members of their families (father, brother, husband) had been nickel mine workers, but typically for periods that did not exceed 18 mo. Two of these 3 women were 31 and 35 y of age at the time of diagnosis, whereas the
Archives of Environmental Health, Sept-Oct, 1991 by Paquerette Goldberg, Marcel Goldberg, Marie-Josee Marne, Albert Hirsch, Jean Tredaniel
ASBESTOS, in various forms, is a well-known risk factor for certain diseases. Pleural cancer is related to occupational exposure [1,2] (asbestos or fibers of industrial origin) and environmental exposure (e.g., natural fibers in the soil of a region, local industries that use certain materials, asbestos in building materials). [3-5] Persons who live with an occupationally exposed member of the household can also experience exposure. [6]
Related Results
* Unusually High Incidence of...
* Malignant pleural mesothelioma...
* Metastatic malignant pleural...
* Pleural mesothelioma cases in...
Most Popular Articles
in Health
* Cocktails and...
* The best damn chest...
* The sour truth about...
* The best self-tanners:...
Within the framework of a study on the relationship between respiratory cancer and occupational exposure in the nickel industry, we collected data on all respiratory cancer cases, including cancer of the pleura, that were diagnosed during a 10-y period (i.e., 1978-1987). In an incidence study and in a case-control study within a cohort of nickel-exposed workers, [7] nickel exposure was excluded in New Caledonia as a risk-factor of respiratory cancer, including, as expected, cancer of the pleura.
The authors considered the possible pathological role of natural asbestos fibers in the soil, especially in the nickel mines, [8,9] to be of sufficient interest to warrant study.
Materials and methods
New Caledonia is a large island in the Southern Pacific region. Of the approximately 145 000 inhabitants, 40% are Melanesian and 40% are European.
Advertisement
All pleural cancer cases that were diagnosed during the preceding 10-y period were reviewed in France by a Certification Committee that was composed of pneumology experts. The cases were then submitted for certification to the French National Committee of Mesothelioma. Twelve cases were certified as primitive pleural cancers, of which 9 were mesothelioma cases. The remaining 3 were probable cases, but clinico-pathological evidence was insufficient. The characteristics of the cases are shown in Table 1.
Residence and occupational history information for the 12 cases was reconstructed during an interview with a family member. Information included details on [TABULAR DATA OMITTED]
all places of residence (name of the town or village, years of arrival and departure) and a description of all employment activities (i.e., type of work and dates of employment that were related to occupational exposure, if any).
The incidence of pleural cancer in New Caledonia was compared with five reference cancer registers that were representative of (a) different levels of industrialization; (b) the Anglo-Saxon and French lifestyles; and (c) various regions of the world, including the Pacific. Standardized Incidence Ratios (SIRs) were calculated by indirect standardization and were based on the age structure of the population. The observed number of cases was compared with the number expected (Poisson).
Results
The comparisons between cases in New Calendonia and the 5 reference registers are presented in Table 2. In all instances, the observed number of cases of pleural cancer in New Calendonia was higher than expected. The differences were statistically significant for the population as a whole and also for Melanesians.
The excess of pleural cancer cases was low compared with the results of other observations in nonoccupationally exposed populations, [10] and it could be related to an environmental or occupational factor. Identification of a possible cause for this excess in New Caledonia was investigated, and residential and occupational histories of the 12 cases were examined.
The interviews revealed that all 12 patients had lived at least part of their lives in rural areas (i.e., the bush). Other characteristics that were related to residence were extremely variable (Fig. 1). Some patients had always resided in the bush in the same region (i.e., Hienghene region, case no. 5; Kouaoua region, case no. 9; Moindou region, case no. 11; Bourail region, case no. 7). With the exception of a stay at Paita, case no. 2 had always lived on Lifou island. Case no. 12 resided in the bush for the shortest period of time (i.e., 2 y in the village of Yate).
Only two cases lived primarily in Noumea, which is the largest city (Fig. 1). One-half of the total population of New Caledonia lives in Noumea. The two cases were 58 and 61 y of age at the time of diagnosis. However, the youngest cases (31, 35, and 40 y of age at diagnosis) lived primarily in the central region between Poya and Canala.
Occupational histories varied. Three patients worked in the nickel industry: case no. 4 was an engine driver at a mine for 6 y, case no. 10 was a bargeman for 9 y, and case no. 12 was a clerk in a mine for 1 y. Other cases had work connections with mines, either personally (e.g., transportation of ore by truck) or through their families (e.g., father, brother, husband). Only 3 cases (nos. 2, 3, and 5) did not mention contact with mining.
The 3 women who had mesothelioma (cases no. 7, 8 and 9) were Melanesians, and except for case no. 7 who had lived in the small town of Bourail for 6 y, they had always lived in a tribe (traditional residence). These 3 women maintained traditional occupations, and case no. 7 had been a cook while she lived in Bourail. Members of their families (father, brother, husband) had been nickel mine workers, but typically for periods that did not exceed 18 mo. Two of these 3 women were 31 and 35 y of age at the time of diagnosis, whereas the
Unusually High Incidence of Malignant Pleural Mesothelioma in a Town of Eastern Sicily: An Epidemiological and Environmental Study
Archives of Environmental Health, Nov, 2000 by Luigi Paoletti, Domenico Batisti, Caterina Bruno, Maurizio Di Paola, Antonio Gianfagna, Marino Mastrantonio, Massimo Nesti, Pietro Comba
THE CAUSAL ASSOCIATION between malignant mesothelioma and exposure to asbestos fibers dates back to the early 1960s. This specific neoplastic form, generally localized in the pleura, is a rare tumor, the incidence of which is estimated at 1-2/million persons [multiplied by] y in the general population.[1] Pleural mesothelioma can be caused by occupational, domestic, or residential asbestos exposure; the etiologic role of other factors is negligible.[2]
In a recent epidemiological study on mortality for malignant pleural neoplasms in Italy, Di Paola et al.[3] detected some geographic clusters of cases. For some of the cases, previous asbestos exposure was easily identifiable, whereas for others an occupational exposure could not be suggested.
Given the preceding facts, we found Biancavilla, a town in eastern Sicily located in a volcanic area, to be of special interest. Industrial activities involving asbestos have never occurred in Biancavilla. The subjects who resided in this town--and for whom a diagnosis of pleural mesothelioma had been made--never had any relevant exposure to asbestos during their professional lives.
The results of an environmental survey, which was conducted by the Istituto Superiore di Sanita in collaboration with the local health authorities, suggested that a possible cause of the asbestos exposure of Biancavilla's population was the stone quarries located in Monte Calvario. Monte Calvario is located on the southwest side of the Etnean volcanic complex, northeast of Biancavilla. The materials extracted from the quarries contain large quantities of fibrous amphiboles; these materials are used widely in the local building industry. In consideration of the available data and in view of some analogies with other situations observed in various areas of the Mediterranean basin,[4-8] we undertook an in-depth study of the potential connection between the increased occurrence of pleural mesothelioma and the presence of mineral fibers in the building materials that originated in the stone quarries.
I. Mortality and Morbidity among Residents
I. Material and Method
We studied cause-specific mortality among residents in Biancavilla from 1980 (i.e., the first year for which such figures were available at the municipality level) through 1993 (i.e., the most recent year for which mortality data were provided by the National Institute for Statistics. We selected causes of death for which a causal association with asbestos has been ascertained (e.g., malignant neoplasms of the pleura, peritoneum, and lung) or suspected (e.g., malignant neoplasms of the ovary).
We are aware that the relationship between ovarian cancer and asbestos exposure is controversial. The results of epidemiological and experimental studies indicate a possible association between, ovarian cancer and materials of the talc-asbestos group.[9] Findings relative to gas-mask assemblers in the United Kingdom support this hypothesis,[10 11] and, recently, in two Italian studies researchers reported an increased risk of ovarian cancer in female workers exposed to asbestos.[12 13] In our view, the aforementioned evidence justified the inclusion of ovarian cancer in the mortality study.
For each cause of death, we confronted the observed morality with the corresponding expected value on the basis of cause-sex-age-calendar year-specific morality rates of Sicily's population. To this end, we used the epidemiological databank of the National Board for Energy, New Technology and Environment. Standardized mortality ratios (SMRs) were computed, and we estimated their 95% confidence intervals (CIs) in accordance with Poisson distribution.
Cases of pleural mesothelioma were searched thoroughly via the files of Biancavilla Registrar Office and hospital discharge cards. Patients or their close relatives were interviewed about previous fiber exposure, and we used guidelines of the National Registry of Mesotheliomas[14] to assign them to exposure categories.
I. Results
Mortality. A significant increase in mortality from malignant pleural neoplasms occurred in Biancavilla during the study period (Table 1). The increase was relatively stronger (a) among women, (b) in subjects 65 y of age or less, and (c) during the most recent years. No comparable finding could be detected in any of the neighboring municipalities.
Table 1.--Mortality from Malignant Pleural Neoplasms in Biancavilla, 1980-1993: Analysis by Age, Class, and Calendar Year
Men
Year and age Obs. Exp. SMR 95% CI
1980-1993:
all ages 4 1.57 255 69, 652
1980-1987:
all ages 2 0.74 270 33, 976
1988-1993:
all ages 2 0.82 244 30, 881
1980-1993:
< 65 y of age 2 0.62 323 39, 1,165
1980-1993:
[is greater than or
equal to] 65 y of age 2 0.95 211 26, 761
Women
Year and age Obs. Exp. SMR 95% CI
198.0-1993:
all ages 5 0.74 676 219, 1,577
1980-1987:
all ages 2 0.40 500 61, 1,806
1988-1993:
all ages 3 0.33 909 188, 2,657
1980-1993:
< 65 y of age 3 0.27 1,111 229, 3,247
1980-1993:
[is greater than or
equal to] 65 y of age 2 0.48 417 51, 1,505
Total
Year and age Obs. Exp. SMR 95% CI
198.0-1993:
all ages 9 2.31 390 178, 740
1980-1987:
all ages 4 1.14 351 96, 898
1988-1993:
all ages 5 1.15 435 141, 1,015
1980-1993:
< 65 y of age 5 0.89 562 182, 1,311
1980-1993:
[is greater than or
equal to] 65 y of age 4 1.43 280 76, 716
THE CAUSAL ASSOCIATION between malignant mesothelioma and exposure to asbestos fibers dates back to the early 1960s. This specific neoplastic form, generally localized in the pleura, is a rare tumor, the incidence of which is estimated at 1-2/million persons [multiplied by] y in the general population.[1] Pleural mesothelioma can be caused by occupational, domestic, or residential asbestos exposure; the etiologic role of other factors is negligible.[2]
In a recent epidemiological study on mortality for malignant pleural neoplasms in Italy, Di Paola et al.[3] detected some geographic clusters of cases. For some of the cases, previous asbestos exposure was easily identifiable, whereas for others an occupational exposure could not be suggested.
Given the preceding facts, we found Biancavilla, a town in eastern Sicily located in a volcanic area, to be of special interest. Industrial activities involving asbestos have never occurred in Biancavilla. The subjects who resided in this town--and for whom a diagnosis of pleural mesothelioma had been made--never had any relevant exposure to asbestos during their professional lives.
The results of an environmental survey, which was conducted by the Istituto Superiore di Sanita in collaboration with the local health authorities, suggested that a possible cause of the asbestos exposure of Biancavilla's population was the stone quarries located in Monte Calvario. Monte Calvario is located on the southwest side of the Etnean volcanic complex, northeast of Biancavilla. The materials extracted from the quarries contain large quantities of fibrous amphiboles; these materials are used widely in the local building industry. In consideration of the available data and in view of some analogies with other situations observed in various areas of the Mediterranean basin,[4-8] we undertook an in-depth study of the potential connection between the increased occurrence of pleural mesothelioma and the presence of mineral fibers in the building materials that originated in the stone quarries.
I. Mortality and Morbidity among Residents
I. Material and Method
We studied cause-specific mortality among residents in Biancavilla from 1980 (i.e., the first year for which such figures were available at the municipality level) through 1993 (i.e., the most recent year for which mortality data were provided by the National Institute for Statistics. We selected causes of death for which a causal association with asbestos has been ascertained (e.g., malignant neoplasms of the pleura, peritoneum, and lung) or suspected (e.g., malignant neoplasms of the ovary).
We are aware that the relationship between ovarian cancer and asbestos exposure is controversial. The results of epidemiological and experimental studies indicate a possible association between, ovarian cancer and materials of the talc-asbestos group.[9] Findings relative to gas-mask assemblers in the United Kingdom support this hypothesis,[10 11] and, recently, in two Italian studies researchers reported an increased risk of ovarian cancer in female workers exposed to asbestos.[12 13] In our view, the aforementioned evidence justified the inclusion of ovarian cancer in the mortality study.
For each cause of death, we confronted the observed morality with the corresponding expected value on the basis of cause-sex-age-calendar year-specific morality rates of Sicily's population. To this end, we used the epidemiological databank of the National Board for Energy, New Technology and Environment. Standardized mortality ratios (SMRs) were computed, and we estimated their 95% confidence intervals (CIs) in accordance with Poisson distribution.
Cases of pleural mesothelioma were searched thoroughly via the files of Biancavilla Registrar Office and hospital discharge cards. Patients or their close relatives were interviewed about previous fiber exposure, and we used guidelines of the National Registry of Mesotheliomas[14] to assign them to exposure categories.
I. Results
Mortality. A significant increase in mortality from malignant pleural neoplasms occurred in Biancavilla during the study period (Table 1). The increase was relatively stronger (a) among women, (b) in subjects 65 y of age or less, and (c) during the most recent years. No comparable finding could be detected in any of the neighboring municipalities.
Table 1.--Mortality from Malignant Pleural Neoplasms in Biancavilla, 1980-1993: Analysis by Age, Class, and Calendar Year
Men
Year and age Obs. Exp. SMR 95% CI
1980-1993:
all ages 4 1.57 255 69, 652
1980-1987:
all ages 2 0.74 270 33, 976
1988-1993:
all ages 2 0.82 244 30, 881
1980-1993:
< 65 y of age 2 0.62 323 39, 1,165
1980-1993:
[is greater than or
equal to] 65 y of age 2 0.95 211 26, 761
Women
Year and age Obs. Exp. SMR 95% CI
198.0-1993:
all ages 5 0.74 676 219, 1,577
1980-1987:
all ages 2 0.40 500 61, 1,806
1988-1993:
all ages 3 0.33 909 188, 2,657
1980-1993:
< 65 y of age 3 0.27 1,111 229, 3,247
1980-1993:
[is greater than or
equal to] 65 y of age 2 0.48 417 51, 1,505
Total
Year and age Obs. Exp. SMR 95% CI
198.0-1993:
all ages 9 2.31 390 178, 740
1980-1987:
all ages 4 1.14 351 96, 898
1988-1993:
all ages 5 1.15 435 141, 1,015
1980-1993:
< 65 y of age 5 0.89 562 182, 1,311
1980-1993:
[is greater than or
equal to] 65 y of age 4 1.43 280 76, 716
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