tremolite and Pleural-Diseases

A 51-year-old man underwent pleuroscopy for radiologic pleural abnormalities. Pathologic examination of pleural and lung biopsy specimens concluded on hyalinized pleural plaques associated with mild asbestosis. Transmission electron microscopy analysis showed significant retention of tremolite asbestos fibers. The absence of any occupational exposure to asbestos and the existence of geologic deposits of tremolite in the Kabul area of Afghanistan suggest an environmental exposure during the patient's childhood spent in this region.

Topics: Afghanistan; Air Pollutants; Asbestos, Amphibole; Asbestosis; Biopsy; Environmental Exposure; Humans; Lung; Male; Middle Aged; Pleura; Pleural Diseases

In 2000, the Agency for Toxic Substances and Disease Registry (ATSDR; Atlanta, GA, USA) investigated lung disease in those exposed to the tremolite-contaminated vermiculite mine in Libby, MT, USA. Previously unreported spirometric results are presented here in relation to exposure and radiographic findings. 4,524 study participants were assigned to one of seven mutually exclusive exposure categories. Associations among radiographic findings, spirometric results and exposure were investigated, along with the effect of a reduction in exposure potential when production was moved to a wet process mill in the mid 1970s. Spirometry data for the total population by smoking status and age were within the normal range. Prevalence of pleural plaque increased with age, but was lowest in the environmentally exposed group (0.42-12.74%) and greatest in the W.R. Grace & Co. mineworkers (20-45.68%). For males, there was a significant (4.5%) effect of pleural plaques on forced vital capacity. For W.R. Grace & Co. workers and household contacts, a reduction in plaque (0.11 versus 1.64%) and in diffuse pleural thickening or costophrenic angle obliteration (1.94 and 0.13%) was noted for those exposed after 1976. These analyses do not support a clinically important reduction in spirometry of this cohort. The 1976 reductions in exposure have led to decrease in radiographic changes.

Topics: Adult; Aged; Aged, 80 and over; Aluminum Silicates; Asbestos, Amphibole; Cohort Studies; Environmental Exposure; Female; Humans; Lung; Male; Middle Aged; Mining; Montana; Pleural Diseases; Prevalence; Radiography; Respiratory Function Tests; Smoking

Mediterranean regions such as Greece, Turkey, Cyprus, Corsica and New Caledonia have experienced epidemics of malignant mesothelioma as a result of non-occupational, "domestic" exposure to tremolite asbestos and fibrous erionite. This exposure to tremolite asbestos and fibrous erionite is typified "domestic" due to its prevalence in regions with natural deposits of tremolite asbestos (or fibrous erionite) where the material from tremolite asbestos or fibrous erionite is used for domestic applications such as whitewashing. However, these exposures may be useful in examining the potential consequences of even small amounts of amphibole asbestos fibers in the ambient air. It can also elucidate the effects of fibers that behave like amphibole asbestos. However, this type of exposure is not useful for studying the potential effects of small amounts of asbestos in the ambient air of big cities due to the differing nature of the fiber types and modes of exposure between the regions.

Topics: Air Pollutants; Asbestos, Amphibole; Asbestosis; Calcinosis; Carcinogens, Environmental; Disease Outbreaks; Female; Humans; Male; Mediterranean Region; Mesothelioma; Mineral Fibers; Pleural Diseases; Zeolites

The progress of pleural plaques in persons exposed to environmental asbestos in Almopia, Greece were studied prospectively.. During a 15-year period, 198 individuals, in whom pleural plaques had been observed during the period 1988-1990 were followed. Respiratory function was initially evaluated in 23. All were inhabitants of seven villages of Northern Greece, where rocks with high concentration in asbestos fibers were used for whitewashing until 1935.. Out of this population, 126 survived and underwent chest X-ray in 2003 while respiratory function was retested in 18. New radiological findings were compared to previous ones using digital technology. Furthermore, the cause of death of the remaining 72 was recorded. Deterioration of X-ray findings was observed in all survivors. Not only did the surface area of previous plaques increase (8.66 +/- 12.6 cm2, mean value +/- SD) but new ones also appeared. Total lung capacity decreased from 95.6 +/- 14.8 in 1998 to 76.5 +/- 9.3% predicted in 2003. It was found that out of 72 deaths, 11 people died of malignant lung neoplasm, and 4 of mesothelioma.. Radiological appearance of pleural plaques and respiratory function of people previously exposed to asbestos environmental pollution worsens over the years. Prevalence of mesothelioma was found to be higher than expected.

Topics: Adult; Aged; Asbestos; Asbestos, Amphibole; Disease Progression; Environmental Exposure; Female; Greece; Humans; Male; Mesothelioma; Pleura; Pleural Diseases; Prospective Studies; Rural Population; Time Factors

Twenty years ago, we reported on a very high prevalence of pleural calcifications (PCs) and malignant mesothelioma among inhabitants of Metsovo, in northwestern Greece. It was shown that both abnormalities were related to asbestos exposure from a whitewash containing tremolite. The fading use of this material has resulted in a decreased incidence of mesothelioma (one third of the original incidence). The aim of the present study was to examine whether PCs among Metsovites has followed a similar trend.. Retrospective study.. University Hospital of Ioannina, a tertiary teaching hospital, "G. Hadjikosta" Hospital, a tertiary hospital in Ioannina, and Metsovo Health Center, a primary care center in the town of Metsovo.. Chest roentgenograms of 307 Metsovites, obtained between from 1998 to 2002 were examined. The prevalence of PCs was compared to the one noted 20 years ago.. A significantly lower prevalence of calcifications was observed now among younger Metsovites (< 60 years of age). In both studies, there was an increasing rate of PC with age.. The findings of the present study strengthen the incrimination of the whitewash containing tremolite in the development of PCs in Metsovites. The withdrawal of its use in the area has resulted in a null prevalence of PCs in individuals < 40 years old.

Topics: Adult; Aged; Asbestos; Asbestos, Amphibole; Calcinosis; Environmental Exposure; Female; Greece; Humans; Male; Mesothelioma; Middle Aged; Pleural Diseases; Pleural Neoplasms; Prevalence; Retrospective Studies

The community of Libby, Montana has recently been the focus of national attention secondary to widespread amphibole contamination associated with vermiculite mining and processing.. Patients who had occupational and non-occupational exposure to amphibole asbestos in Libby, Montana were evaluated for progressive loss of pulmonary function.. Of the 123 patients evaluated, 94 demonstrated average age-corrected accelerated loss per year of vital capacity at 3.2%, total lung capacity (TLC) 2.3%, and DLCO 3.3%. All patients all had predominantly pleural changes with minimal to no interstitial disease.. The study demonstrates a progressive loss of pulmonary function in patients exposed to tremolite asbestos.

Topics: Aged; Asbestos, Amphibole; Asbestosis; Disease Progression; Female; Humans; Male; Mining; Montana; Occupational Exposure; Pleural Diseases; Prevalence; Respiratory Function Tests; Risk Factors

Inhabitants of Metsovo in northwest Greece have been exposed to asbestos from use of a tremolite-containing whitewash ("luto" soil). As a result, they have increased incidence of malignant pleural mesothelioma and pleural calcifications (PCs). However, subjects with calcifications have a much lower incidence of mesothelioma than those without. A previous study of the two groups with BAL revealed higher proportional lymphocytosis among subjects with calcifications. We suggested that BAL lymphocytosis may be somehow correlated with "protection" against neoplasia.. The present report is a study of the liquid phase of BAL in the two groups. BAL specimens of 43 Metsovites (13 subjects with PCs and 30 subjects without PCs) and two control groups were examined. We measured total protein, albumin, IgG, IgA, and interleukin-6. Proteins were analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis and further characterized using an appropriate computer program.. The most interesting finding was the presence of two additional protein spots corresponding to the electrophoretic site of Ig heavy chain and C(4) component of complement. The two proteins were present in all Metsovites with PCs but in none without PCs and also in none of the control groups.. This study further separates two groups of Metsovites with different reaction to asbestos, possibly as a result of different activation of alveolar macrophages. This difference leads the first group to the formation of PCs, BAL fluid lymphocytosis, and relative "protection" against malignancy, and the second group to no calcifications, no lymphocytosis, but also no protection against malignancy.

Topics: Adult; Aged; Asbestos, Amphibole; Asbestosis; Bronchoalveolar Lavage Fluid; Calcinosis; Complement C4; Environmental Exposure; Female; Greece; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin Heavy Chains; Interleukin-6; Lymphocytosis; Male; Mesothelioma; Middle Aged; Pleural Diseases; Pleural Neoplasms; Prognosis; Proteins

Deposits of carbonate rock like limestone and dolomite may contain tremolite asbestos. This study assessed the exposure to tremolite asbestos and the respiratory health of Swedish dolomite workers.. 95% of 137 eligible workers at two dolomite producing companies completed a self administered questionnaire that included questions on respiratory symptoms and were examined with spirometry as well as chest radiography. Total exposure to dust was gravimetrically measured and the tremolite asbestos content of the dust was assessed with polarisation and phase contrast microscopy.. Dolomite dust concentrations were moderate (median 2.8 mg/m3) and tremolite asbestos concentrations were generally below the limit of detection (<0.03 fibres/ml). Somewhat higher values, around 0.1 fibres/ml, were obtained in manual stone sorting and bagging. Respiratory symptoms suggestive of chronic bronchitis were more related to smoking than to estimates of individual exposure to dust. The mean vital capacity was 0.2 l lower than expected after adjustment for sex, age, height, and smoking but the decline in lung function was not associated with current or cumulative exposure to dust in a clear cut way. Two definite cases of pleural plaques and one possible case of simple pneumoconiosis were noted, but the plaques could not be attributed exclusively to exposure to tremolite asbestos.. Dolomite mining and milling may indeed entail low levels of exposure to tremolite asbestos, but this exposure was not a strong determinant of respiratory symptoms, lung function, or pneumoconiosis in exposed Swedish workers. This was true also for dolomite dust. The hazards of exposure to tremolite asbestos may vary across deposits, however, and additional studies at other sites of carbonate rock exploitation are warranted.

Topics: Adult; Asbestos, Amphibole; Calcium Carbonate; Confidence Intervals; Cross-Sectional Studies; Dust; Female; Forced Expiratory Volume; Humans; Logistic Models; Lung Diseases, Obstructive; Magnesium; Male; Microscopy, Phase-Contrast; Microscopy, Polarization; Middle Aged; Mining; Occupational Exposure; Odds Ratio; Pleural Diseases; Pneumoconiosis; Radiography; Smoking; Vital Capacity

To examine how fiber type, fiber concentration, and fiber size correlate with the presence of asbestos-related disease in workers with heavy chrysotile exposure, we used analytic electron microscopy to determine the fiber content of the lungs of 94 long-term chrysotile miners and millers from the region of Thetford Mines, Quebec. Mesothelioma, airway fibrosis, and asbestosis were strongly associated with a high tremolite fiber concentration, whereas pleural plaques and carcinoma of the lung showed no relationship to tremolite burden. Similar patterns were seen for chrysotile concentration, but further analysis suggested that the apparent effect of chrysotile probably was due to the high correlation (r = 0.70) between chrysotile and tremolite concentration rather than to an independent effect of chrysotile. Increased tremolite-chrysotile ratio was marginally associated with the presence of pleural plaques but not with any other disease. Very high correlations (r > 0.90) between the concentrations of fibers longer or shorter than 8 microns prevented assessment of the effects of long compared with short fibers. Pleural plaques were very strongly associated with higher mean tremolite fiber aspect ratios, but no differences in mean fiber size (length, width, aspect ratio, surface area, and mass) were seen for any other disease. Total fiber size measures (total fiber length/g and others) showed differences similar to fiber concentration for mesothelioma, airways fibrosis, and asbestosis, but no one measure was clearly better than another or better than fiber concentration. We conclude that, in this population of heavily exposed chrysotile miners and millers, the presence of airways fibrosis and asbestosis and, probably, mesothelioma reflects high tremolite burden.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aged; Asbestos; Asbestos, Amphibole; Asbestos, Serpentine; Asbestosis; Humans; Lung; Lung Neoplasms; Mesothelioma; Microscopy, Electron; Middle Aged; Mining; Particle Size; Pleural Diseases; Pulmonary Fibrosis; Quebec; Regression Analysis; Silicic Acid

The purpose of this study was to determine whether the inhabitants of villages environmentally exposed to asbestos, in northeast Corsica, had a higher incidence of pleural plaques. X-rays were obtained from subjects aged over 50 yrs, with no occupational exposure to asbestos or history of pleural disease, in one village exposed to asbestos, Murato, and a nonexposed, control village, Vezzani. In addition, the mineral content of the air and parietal pleura of animals in the exposed zone was studied, using transmission electron microscopy. The incidence of bilateral pleural plaques in the exposed population was 41%, as compared to 7.5% in the nonexposed population (p < 0.00001). The levels of airborne tremolite were higher in Murato (6-72 ng.m-3) than in Vezzani (< 1 ng.m-3), but chrysotile levels were similar. Significant numbers of chrysotile and tremolite fibres were identified in the parietal pleura of animals from the exposed village. This study confirms the well-known correlation between bilateral pleural plaques and environmental exposure to low levels of asbestos.

Topics: Aged; Air Pollutants; Animals; Asbestos; Asbestos, Amphibole; Asbestos, Serpentine; Asbestosis; Dogs; Environmental Exposure; Female; France; Goats; Humans; Incidence; Male; Middle Aged; Pleura; Pleural Diseases; Prevalence; Silicic Acid

Endemic PCs and high incidence of malignant mesothelioma from household use of asbestos have been reported in Metsovo in northwestern Greece ("Metsovo lung"). In the present study, we present similar findings in six more areas of Greece. Like Metsovo, all these areas are located within ophiolite belts. Like Metsovo, material similar to "Metsovo whitewash" has been used for various domestic uses. Asbestos fibers (chrysotile, antigorite and tremolite) were found in three of the six areas. Also, in two, MPM has been diagnosed. These findings suggest that "Metsovo lung" occurs in several areas of Greece and has similar etiology and epidemiology.

Topics: Aged; Asbestos; Asbestos, Amphibole; Asbestosis; Calcinosis; Environmental Exposure; Greece; Humans; Incidence; Mesothelioma; Middle Aged; Pleural Diseases; Pleural Neoplasms; Silicic Acid; Soil

In north-east Corsica, asbestos outcrops are a source of environmental pollution, as assessed by airborne concentrations of chrysotile and tremolite that are significantly higher in the north-east than the north-west. For this reason we compared the frequencies of patients with asbestos pleural plaques in these 2 regions by checking the X-rays of 1721 patients born in north Corsica who had not undergone any occupational exposure to asbestos. The percentage of plaques was respectively 3.7% in the north-east, and 1.1% in the north-west (p less than 0.05). The relative risk of 3.3 demonstrates a strong relationship between environmental asbestos and the pleural plaques found in north-east Corsica.

Topics: Aged; Air Pollutants; Asbestos; Asbestos, Amphibole; Asbestos, Serpentine; Female; France; Humans; Male; Pleural Diseases; Radiography; Silicic Acid; Silicon Dioxide

Topics: Asbestos, Amphibole; Calcinosis; Greece; Humans; Mesothelioma; Paint; Pleural Diseases; Silicic Acid; Silicon Dioxide

We report four cases of pleural plaques found at autopsy in individuals who resided in or near the chrysotile mining town of Thetford Mines, Quebec, and who had never been employed in the chrysotile mining and milling industry. Three of these patients were farmers, and one was a road construction worker. Lung asbestos content of these cases was compared with that of a group of nine persons living in the same vicinity who did not have pleural plaques. The plaque group was found to have an equal chrysotile content but about a fourfold elevation in median tremolite content, a statistically significant increase. Fiber sizes were the same in both groups. Also, one plaque case had an elevated level of relatively long titanium oxide fibers. These observations suggest that environmental pleural plaques in this region of Quebec are probably caused by exposure to tremolite derived from local soil and rock and that other types of mineral fibers such as titanium oxide may occasionally also be the cause of such lesions.

Topics: Aged; Asbestos; Asbestos, Amphibole; Asbestos, Serpentine; Asbestosis; Environmental Pollution; Humans; Lung; Male; Mining; Pleural Diseases; Quebec; Silicic Acid; Silicon Dioxide; Titanium

Topics: Adult; Asbestos; Asbestos, Amphibole; Environmental Exposure; Female; Humans; Lung Diseases; Male; Mesothelioma; Pleural Diseases; Pleural Neoplasms; Rural Population; Silicic Acid; Silicon Dioxide; Turkey

Radiologic screening of 688 inhabitants of the Metsovo area in Northwest Greece revealed that 323 (46.9 percent) had pleural calcifications. The percentage of positive examinations rose with age. Calcifications were observed in all four villages of the area where a material ("luto" soil) had been extensively used for whitewashing until 1940 to 1950. In four other villages in the immediate vicinity, where "luto" had never been used, pleural calcifications were not observed. Results suggest that Metsovo tremolite may have caused pleural calcifications to all individuals born in Metsovo before 1940. This is the first study indicating that environmental asbestos exposure can cause abnormalities in everyone exposed to it.

Topics: Adult; Aged; Asbestos, Amphibole; Calcinosis; Environmental Exposure; Female; Greece; Humans; Male; Middle Aged; Paint; Pleural Diseases; Silicic Acid; Silicon Dioxide; Tomography, X-Ray Computed

Topics: Asbestos, Amphibole; Calcinosis; Greece; Humans; Pleural Diseases; Silicic Acid; Silicon Dioxide

Chest radiographs taken by a standard technique were obtained from 173 current employees (164 men, 9 women) of a vermiculite mine in Montana, from 80 of 110 past employees resident within 200 miles, and from 47 men from the same area without known exposure to dust. In 43 of the 80 and 24 of the 47 an earlier chest x ray film was retrieved from the hospital archives. All 367 films were assessed blind and independently by three experienced readers using the ILO 1980 classification. Median radiographic assessment scores were analysed in relation to estimated cumulative exposure to the amphibole fibres that contaminate the vermiculite. Logistic regression analyses showed independent effects of age, smoking, and exposure on the prevalence of small opacities and of age and probably of exposure on pleural thickening. Overall, the data suggest that by retirement age the increase in prevalence of small opacities (greater than or equal to 1/0) lies between 5% and 10% per 100 f/ml years. This gradient may be somewhat steeper than for chrysotile miners and millers, but not much so.

Topics: Adult; Age Factors; Aged; Aluminum Silicates; Asbestos, Amphibole; Female; Humans; Lung; Lung Diseases; Male; Middle Aged; Mining; Occupational Diseases; Pleura; Pleural Diseases; Radiography; Silicic Acid; Silicon Dioxide