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Ronald F. Dodson - One of the best experts on this subject based on the ideXlab platform.
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Omentum and Mesentery
2015Co-Authors: Ronald F. Dodson, D. Holiday, Ju Huang, Samuel P. HammarAbstract:Study objectives: Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers. Design: Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy. Results: Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and Ferruginous Body burden. An increased total Ferruginous Body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p < 0.05). Conclusion: Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue. (CHEST 2000; 117:486 ‐ 493)
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Characteristics of Asbestos Concentration in Lung as Compared to Asbestos Concentration in Various Levels of Lymph Nodes that Collect Drainage from the Lung
Ultrastructural pathology, 2007Co-Authors: Ronald F. Dodson, Sara Shepherd, Jeffrey L. Levin, Samuel P. HammarAbstract:Inhaled dust particulates are able to relocate to the extrapulmonary compartments, particularly the lymph nodes that drain the lung. There is little information about the concentration and type of asbestos in the lymphatics and lymph nodes. Quantitative analysis of asbestos lymph node burden conducted by light and analytical transmission electron microscopy has shown Ferruginous bodies in lymph nodes that drain the lung and appreciable numbers of short asbestos fibers accumulate in lymph nodes in occupationally exposed individuals. The location of lymph nodes in the thoracic cavity was categorized according to the Naruke anatomical map. Tissue from eleven individuals with a history of asbestos exposure were selected for a comparative study of the asbestos content of lung with that found in the thoracic lymph nodes. The study used a digestion technique for tissue preparation and evaluated Ferruginous Body burden and concentration of asbestos fibers (> 0.5 µm in length). Comparison was made between sites an...
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Stability of Ferruginous bodies in human lung tissue following death, embalmment, and burial.
Inhalation toxicology, 2005Co-Authors: Ronald F. Dodson, Mark A. L. Atkinson, Michael O'sullivanAbstract:The identification of asbestos bodies in tissue sections is an indicator of past exposure to longer asbestos fibers. These structures are formed in lung tissue as a consequence of interactions with pulmonary macrophages resulting in the deposition of a ferroprotein (Ferruginous) coating on the fiber. While the process of Ferruginous Body formation is known to take months in animal tissue, there is no published information on the stability of Ferruginous bodies in tissue following death. The material assessed in the present study was obtained from lung material collected from an exhumed Body approximately 8(1/2) mo after death, embalmment, and burial. Tissue sections were reviewed for the presence of asbestos bodies. Additional pieces of lung tissue were digested, with the digestate being evaluated by light microscopy for Ferruginous bodies and by electron microscopy for uncoated asbestos fibers and core analysis of asbestos bodies. Classical Ferruginous (asbestos) bodies were found in abundance in the tissue sections including in areas with fibrosis. The levels of uncoated asbestos fibers and classical appearing Ferruginous bodies (asbestos bodies) were consistent with occupational levels of tissue burden. The data from this study indicate that Ferruginous bodies remain morphologically stable within the tissue for months following death, embalmment, and burial. Thus the lung tissue from this exhumed individual was usable not only to pathologically confirm asbestosis but also to provide quantitative data of occupational exposure to asbestos.
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Asbestos burden in cases of mesothelioma from individuals from various regions of the United States.
Ultrastructural pathology, 2005Co-Authors: Ronald F. Dodson, Michael O'sullivan, Russell Graef, Sara Shepherd, Jeffrey L. LevinAbstract:Mesothelioma is a rare tumor that is considered an asbestos marker disease. It occurs in individuals following a longer latency period from first exposure than other asbestos-related diseases. The tumor also occurs in individuals with a wide range of exposures, including individuals with lower level or secondary exposures. In the present study lung tissue from 54 individuals with a pathological diagnosis of mesothelioma was evaluated for Ferruginous Body and uncoated asbestos fiber content. The data were compared with an earlier study of mesothelioma cases from the northwestern United States. Tissue was prepared via a digestion procedure, with the collected digestate reviewed by light microscopy for quantification of asbestos bodies and analytical transmission electron microscopy for determination of uncoated fiber burden. Twenty-seven cases in the present study had over 1000 Ferruginous bodies per gram of dry tissue. The data suggest that amosite provides a more likely stimulus for Ferruginous coating th...
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Asbestos content of omentum and mesentery in nonoccupationally exposed individuals. Toxicol. Ind. Health 17:138–143
2001Co-Authors: Ronald F. Dodson, Michael A F O’sullivan, Dwaina A R Brooksa, James R BrucebAbstract:Asbestos fibers in occupationally exposed individuals relocate from the lung to extrapulmonary sites. A mechanism for relocation is via the lymphatic circulation. Indeed, asbestos fibers have been found in lymph nodes as well as pleural plaques. Our laboratory has recently shown that asbestos fibers also reach the mesentery and omentum in the peritoneal area where a small percentage of mesotheliomas occurs in exposed individuals. The present study uses light and analytical transmission electron microscopy for defining the asbestos burden in digested lung, omentum, and mesentery tissues from individuals considered as representing the general population in East Texas. The findings, when compared with previous data from occupationally exposed individuals, indicate extreme contrasts as to the level and types of fiber burden between individuals representing the groups. Toxicology and Industrial Health 2001: 17, 138 ± 143. Key words: asbestos; extrapulmonary sites; Ferruginous Body; fibers; mesentery; omentu
Samuel P. Hammar - One of the best experts on this subject based on the ideXlab platform.
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Omentum and Mesentery
2015Co-Authors: Ronald F. Dodson, D. Holiday, Ju Huang, Samuel P. HammarAbstract:Study objectives: Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers. Design: Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy. Results: Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and Ferruginous Body burden. An increased total Ferruginous Body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p < 0.05). Conclusion: Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue. (CHEST 2000; 117:486 ‐ 493)
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Characteristics of Asbestos Concentration in Lung as Compared to Asbestos Concentration in Various Levels of Lymph Nodes that Collect Drainage from the Lung
Ultrastructural pathology, 2007Co-Authors: Ronald F. Dodson, Sara Shepherd, Jeffrey L. Levin, Samuel P. HammarAbstract:Inhaled dust particulates are able to relocate to the extrapulmonary compartments, particularly the lymph nodes that drain the lung. There is little information about the concentration and type of asbestos in the lymphatics and lymph nodes. Quantitative analysis of asbestos lymph node burden conducted by light and analytical transmission electron microscopy has shown Ferruginous bodies in lymph nodes that drain the lung and appreciable numbers of short asbestos fibers accumulate in lymph nodes in occupationally exposed individuals. The location of lymph nodes in the thoracic cavity was categorized according to the Naruke anatomical map. Tissue from eleven individuals with a history of asbestos exposure were selected for a comparative study of the asbestos content of lung with that found in the thoracic lymph nodes. The study used a digestion technique for tissue preparation and evaluated Ferruginous Body burden and concentration of asbestos fibers (> 0.5 µm in length). Comparison was made between sites an...
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Asbestos in Extrapulmonary Sites: Omentum and Mesentery
Chest, 2000Co-Authors: Ronald F. Dodson, D. Holiday, Michael O'sullivan, Ju Huang, Samuel P. HammarAbstract:Study objectives Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers. Design Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy. Results Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and Ferruginous Body burden. An increased total Ferruginous Body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p Conclusion Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue.
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Clinical InvestigationsAsbestos in Extrapulmonary Sites: Omentum and Mesentery
Chest, 2000Co-Authors: Ronald F. Dodson, D. Holiday, Michael O'sullivan, Ju Huang, Samuel P. HammarAbstract:Study objectives Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers. Design Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy. Results Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and Ferruginous Body burden. An increased total Ferruginous Body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p Conclusion Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue.
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Analysis of Asbestos Fiber Burden in Lung Tissue from Mesothelioma Patients
Ultrastructural pathology, 1997Co-Authors: Ronald F. Dodson, Michael O'sullivan, C. J. Corn, Jerry W. Mclarty, Samuel P. HammarAbstract:Mesothelioma is a rare neoplasm that occurs most frequently in individuals with previous asbestos exposure. Differences for risk of development of asbestos-related mesothelioma and lung cancer have been attributed to the various types of asbestos, as well as to the dimension of the inhaled fibers. In the present study, 55 individuals with the pathological diagnosis of mesothelioma were evaluated as to Ferruginous Body and fiber content in lung tissue. The procedures used in the analysis included tissue digestion and analysis of the collected material for Ferruginous bodies by light microscopy and for uncoated fibers by analytical transmission electron microscopy. Forty-six of the samples had Ferruginous Body concentrations of over 1000/per gram dry weight of lung tissue. The majority of the cores of these Ferruginous bodies were amosite. Likewise, the most common uncoated asbestos fiber in the tissue was amosite. Only a small percentage of each type of asbestos would have been visible by light microscopy or even potentially by electron microscopy if the magnification was not sufficient to detect those with thin (< 0.2 micron) diameters. The consistent finding in most of the cases was a considerable presence of asbestos, often of mixed types.
A. Dufresne - One of the best experts on this subject based on the ideXlab platform.
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Ferruginous Body counts in sputum as an index of past exposure to terminal fibres
Annals of Occupational Hygiene, 1992Co-Authors: J.c. Mcdonald, Patrick Sebastien, B.w. Case, A.d. Mcdonald, A. DufresneAbstract:Previous work by our group among vermiculite miners exposed to fibrous tremolite demonstrated that asbestos Body counts in sputum closely reflected intensity and duration of past exposure. In the present project sputum samples from nearly 600 volunteers from 11 cohorts of workers exposed to asbestos and other mineral fibres were found to contain much lower numbers of asbestos bodies than had been observed in vermiculite workers and these counts did not reliably reflect past levels of exposure. No evidence was found that Occupational exposure to man-made mineral fibres led to any Ferruginous Body formation. Asbestos Body counts appeared to differentiate between mesothelioma cases and controls and between levels of radiological asbestosis, but in both comparisons, based on small numbers, the power of discrimination was low. Substantial Variation was found both in asbestos Body and in macrophage counts in daily sampling of vermiculite workers but it was not sufficient to invalidate comparison between groups for epidemiological study. In individual subjects, however, little reliance can be put on results from a single sputum sample, particularly if negative.
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Ferruginous Body counts in sputum as an index of past exposure to mineral fibres.
The Annals of occupational hygiene, 1992Co-Authors: J.c. Mcdonald, Patrick Sebastien, B.w. Case, A.d. Mcdonald, A. DufresneAbstract:Previous work by our group among vermiculite miners exposed to fibrous tremolite demonstrated that asbestos Body counts in sputum closely reflected intensity and duration of past exposure. In the present project sputum samples from nearly 600 volunteers from 11 cohorts of workers exposed to asbestos and other mineral fibres were found to contain much lower numbers of asbestos bodies than had been observed in vermiculite workers and these counts did not reliably reflect past levels of exposure. No evidence was found that occupational exposure to man-made mineral fibres led to any Ferruginous Body formation. Asbestos Body counts appeared to differentiate between mesothelioma cases and controls and between levels of radiological asbestosis, but in both comparisons, based on small numbers, the power of discrimination was low. Substantial variation was found both in asbestos Body and in macrophage counts in daily sampling of vermiculite workers but it was not sufficient to invalidate comparison between groups for epidemiological study. In individual subjects, however, little reliance can be put on results from a single sputum sample, particularly if negative.
Michael O'sullivan - One of the best experts on this subject based on the ideXlab platform.
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Stability of Ferruginous bodies in human lung tissue following death, embalmment, and burial.
Inhalation toxicology, 2005Co-Authors: Ronald F. Dodson, Mark A. L. Atkinson, Michael O'sullivanAbstract:The identification of asbestos bodies in tissue sections is an indicator of past exposure to longer asbestos fibers. These structures are formed in lung tissue as a consequence of interactions with pulmonary macrophages resulting in the deposition of a ferroprotein (Ferruginous) coating on the fiber. While the process of Ferruginous Body formation is known to take months in animal tissue, there is no published information on the stability of Ferruginous bodies in tissue following death. The material assessed in the present study was obtained from lung material collected from an exhumed Body approximately 8(1/2) mo after death, embalmment, and burial. Tissue sections were reviewed for the presence of asbestos bodies. Additional pieces of lung tissue were digested, with the digestate being evaluated by light microscopy for Ferruginous bodies and by electron microscopy for uncoated asbestos fibers and core analysis of asbestos bodies. Classical Ferruginous (asbestos) bodies were found in abundance in the tissue sections including in areas with fibrosis. The levels of uncoated asbestos fibers and classical appearing Ferruginous bodies (asbestos bodies) were consistent with occupational levels of tissue burden. The data from this study indicate that Ferruginous bodies remain morphologically stable within the tissue for months following death, embalmment, and burial. Thus the lung tissue from this exhumed individual was usable not only to pathologically confirm asbestosis but also to provide quantitative data of occupational exposure to asbestos.
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Asbestos burden in cases of mesothelioma from individuals from various regions of the United States.
Ultrastructural pathology, 2005Co-Authors: Ronald F. Dodson, Michael O'sullivan, Russell Graef, Sara Shepherd, Jeffrey L. LevinAbstract:Mesothelioma is a rare tumor that is considered an asbestos marker disease. It occurs in individuals following a longer latency period from first exposure than other asbestos-related diseases. The tumor also occurs in individuals with a wide range of exposures, including individuals with lower level or secondary exposures. In the present study lung tissue from 54 individuals with a pathological diagnosis of mesothelioma was evaluated for Ferruginous Body and uncoated asbestos fiber content. The data were compared with an earlier study of mesothelioma cases from the northwestern United States. Tissue was prepared via a digestion procedure, with the collected digestate reviewed by light microscopy for quantification of asbestos bodies and analytical transmission electron microscopy for determination of uncoated fiber burden. Twenty-seven cases in the present study had over 1000 Ferruginous bodies per gram of dry tissue. The data suggest that amosite provides a more likely stimulus for Ferruginous coating th...
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Asbestos in Extrapulmonary Sites: Omentum and Mesentery
Chest, 2000Co-Authors: Ronald F. Dodson, D. Holiday, Michael O'sullivan, Ju Huang, Samuel P. HammarAbstract:Study objectives Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers. Design Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy. Results Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and Ferruginous Body burden. An increased total Ferruginous Body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p Conclusion Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue.
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Clinical InvestigationsAsbestos in Extrapulmonary Sites: Omentum and Mesentery
Chest, 2000Co-Authors: Ronald F. Dodson, D. Holiday, Michael O'sullivan, Ju Huang, Samuel P. HammarAbstract:Study objectives Asbestos fibers have not been reported in tissues from the peritoneal cavity. Therefore, omentum, mesentery, and lung tissues from 20 individuals in whom mesothelioma was diagnosed were analyzed for asbestos bodies and asbestos fibers. Design Tissue was digested and prepared filters were analyzed by light microscopy and analytical transmission electron microscopy. Results Asbestos bodies were found in the lungs of 18 individuals, mesentery samples from 5, and omentum samples from 2. Uncoated asbestos fibers were found in lungs of 19 patients, 17 of whom had fibers in at least one extrapulmonary site. The most common asbestos in the omentum and mesentery was amosite. Several features of asbestos found in lung influenced the likelihood of amphibole fibers being found in the omentum or mesentery. Lung features included total amphibole fiber burden, length, aspect ratio, and Ferruginous Body burden. An increased total Ferruginous Body burden was strongly associated with increased likelihood of detecting amphiboles in the omentum (p Conclusion Asbestos fibers reach areas in the peritoneal cavity where some mesotheliomas develop. This study suggests their presence can be predicted based on concentrations and characteristics of fiber burdens in lung tissue.
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Analysis of Asbestos Fiber Burden in Lung Tissue from Mesothelioma Patients
Ultrastructural pathology, 1997Co-Authors: Ronald F. Dodson, Michael O'sullivan, C. J. Corn, Jerry W. Mclarty, Samuel P. HammarAbstract:Mesothelioma is a rare neoplasm that occurs most frequently in individuals with previous asbestos exposure. Differences for risk of development of asbestos-related mesothelioma and lung cancer have been attributed to the various types of asbestos, as well as to the dimension of the inhaled fibers. In the present study, 55 individuals with the pathological diagnosis of mesothelioma were evaluated as to Ferruginous Body and fiber content in lung tissue. The procedures used in the analysis included tissue digestion and analysis of the collected material for Ferruginous bodies by light microscopy and for uncoated fibers by analytical transmission electron microscopy. Forty-six of the samples had Ferruginous Body concentrations of over 1000/per gram dry weight of lung tissue. The majority of the cores of these Ferruginous bodies were amosite. Likewise, the most common uncoated asbestos fiber in the tissue was amosite. Only a small percentage of each type of asbestos would have been visible by light microscopy or even potentially by electron microscopy if the magnification was not sufficient to detect those with thin (< 0.2 micron) diameters. The consistent finding in most of the cases was a considerable presence of asbestos, often of mixed types.
J.c. Mcdonald - One of the best experts on this subject based on the ideXlab platform.
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Ferruginous Body counts in sputum as an index of past exposure to terminal fibres
Annals of Occupational Hygiene, 1992Co-Authors: J.c. Mcdonald, Patrick Sebastien, B.w. Case, A.d. Mcdonald, A. DufresneAbstract:Previous work by our group among vermiculite miners exposed to fibrous tremolite demonstrated that asbestos Body counts in sputum closely reflected intensity and duration of past exposure. In the present project sputum samples from nearly 600 volunteers from 11 cohorts of workers exposed to asbestos and other mineral fibres were found to contain much lower numbers of asbestos bodies than had been observed in vermiculite workers and these counts did not reliably reflect past levels of exposure. No evidence was found that Occupational exposure to man-made mineral fibres led to any Ferruginous Body formation. Asbestos Body counts appeared to differentiate between mesothelioma cases and controls and between levels of radiological asbestosis, but in both comparisons, based on small numbers, the power of discrimination was low. Substantial Variation was found both in asbestos Body and in macrophage counts in daily sampling of vermiculite workers but it was not sufficient to invalidate comparison between groups for epidemiological study. In individual subjects, however, little reliance can be put on results from a single sputum sample, particularly if negative.
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Ferruginous Body counts in sputum as an index of past exposure to mineral fibres.
The Annals of occupational hygiene, 1992Co-Authors: J.c. Mcdonald, Patrick Sebastien, B.w. Case, A.d. Mcdonald, A. DufresneAbstract:Previous work by our group among vermiculite miners exposed to fibrous tremolite demonstrated that asbestos Body counts in sputum closely reflected intensity and duration of past exposure. In the present project sputum samples from nearly 600 volunteers from 11 cohorts of workers exposed to asbestos and other mineral fibres were found to contain much lower numbers of asbestos bodies than had been observed in vermiculite workers and these counts did not reliably reflect past levels of exposure. No evidence was found that occupational exposure to man-made mineral fibres led to any Ferruginous Body formation. Asbestos Body counts appeared to differentiate between mesothelioma cases and controls and between levels of radiological asbestosis, but in both comparisons, based on small numbers, the power of discrimination was low. Substantial variation was found both in asbestos Body and in macrophage counts in daily sampling of vermiculite workers but it was not sufficient to invalidate comparison between groups for epidemiological study. In individual subjects, however, little reliance can be put on results from a single sputum sample, particularly if negative.