SEARCH · PubMed Health

Results for “ASBESTOS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources

PubMed2000

Asbestos content in the lymph nodes of nonoccupationally exposed individuals.

BACKGROUND: The thoracic lymph nodes are a part of the clearance system from lung tissue. Accumulation of dust in these nodes are known to occur following some types of exposure. However, no information exists as to asbestos content in lymph nodes from the general population. METHODS: The study cohort consisted of 21 individuals previously defined as nonoccupationally exposed to asbestos. Tissue burden of asbestos obtained from lung analysis by analytical electron microscopy was compared with burden in the lymph nodes. RESULTS: No asbestos fibers were detected in nodes from 8 cases. The majority of the fibers found in lymph nodes were short (<5 microm) and most often noncommercial amphiboles. Ferruginous bodies (FBs) were detected in lymph node from only two samples. CONCLUSIONS: The total asbestos burden in the lung tissue from these individuals was quite low. However, in 12 of the 13 cases that had positive nodes, the tissue burden in the node was appreciably heavier per gram than in the lung. This raises the question as to whether the lymph nodes, though less efficient clearance, may be better indicators of lifetime exposure to dust than lung tissue.

Adolescent↗

PubMed1992

Tobacco, alcohol, asbestos, and occupational risk factors for laryngeal cancer.

Data from a hospital-based case-control study between 1985-1990 were used to examine the effects of tobacco, alcohol, asbestos, and other occupational exposures on laryngeal cancer risk in 194 white men with primary cancer of the larynx and 184 age-matched control subjects. A dose-dependent effect for current cigarette smoking was observed, with higher relative risks (RR) for supraglottic cancer (RR, 21.6 to 68) than for cancer of the glottis (RR, 5.5 to 20.7). Elevated RR for ex-smokers (RR, 4.8) and pipe and cigar smokers (RR, 4.3) did not vary by subsite. The effects of alcohol also showed dose-dependent effects, with higher RR for cancer of the supraglottis than glottis for heavy drinkers (207 ml or more/daily; RR, 9.6 versus 2.5) and binge drinkers (RR, 28.4 versus 8.3). A slightly elevated but not significant association was seen for asbestos exposure and glottic cancer (RR, 1.3). The RR did not increase linearly with the number of years employed in asbestos-related occupations. No relationship was observed between asbestos and cancer of the supraglottis. When examining the data for a synergistic effect of cigarette smoking and asbestos exposure, no excess risk was found. A significantly elevated risk was found for men exposed to diesel fumes (RR, 5.2). Elevated but not significant RR were seen for men chronically exposed to rubber (RR, 6.4) and wood dust or employed as construction laborers, auto mechanics, and other jobs. A significant inverse trend with body mass was observed for cancer of the supraglottis.

Adult↗

PubMed2002

The exposure-time-response relationship between occupational asbestos exposure and lung cancer in two German case-control studies.

BACKGROUND: Numerous studies have been carried out to evaluate the association between lung cancer and occupational asbestos exposure. However, the effects of timing of exposure have not been analyzed thoroughly. METHODS: Two German case-control studies with data on occupational asbestos exposure histories have been pooled. Duration of work in potentially asbestos exposed jobs and two derived weighted exposure measures are analyzed together with time since last exposure. A spline function is used to model the effect of time since exposure. RESULTS: The odds ratios (OR) and corresponding 95% confidence intervals were 1.8 (1.2, 2.7) and 2.4 (1.7, 3.4) for subjects having worked for 3 to 7 years and 8 or more years, respectively, in a job with potential asbestos exposure compared to never-exposed. Based on an evaluation of time since last exposure, the OR decreased significantly to about one-half after more than 20 years since exposure ceased. Using a spline function, applied to workers' complete exposure histories, the effect of an increment of exposure is greatest 10-15 years after that exposure was received. CONCLUSIONS: In contrast to previous indications, the risk of lung cancer increases soon after asbestos exposure, with its maximum effect from 10 to 15 years after the exposure was received.

Adult↗

PubMed2004

The British approach to asbestos standard setting: 1898-2000.

BACKGROUND: The asbestos industry started in the late 1870s, and the first accounts of severe respiratory disease in its workers were published in England (1898, 1906), France (1907), and Italy (1908). For a hundred years, a series of increasingly lower standards were set for asbestos in Britain: initially they purported to prevent asbestosis, and latterly to reduce asbestosis and malignancies to acceptable levels. METHODS: Published accounts of how British asbestos exposure standards came to be derived are reviewed in the light of archival materials originated by industry and government. RESULTS: The earliest standard, of necessity, was not evidence based and while subsequent standards purported to relate doses to effects, the indifferent quality of the measurement of dose, and the poor discrimination of effects, militated against arriving at a standard in which trust should be placed. Each successive standard that was accepted, conformed to what could be achieved in production processes, as far as it was reasonably practicable on technological and economic grounds. CONCLUSIONS: For the better part of a hundred years, confidence was misplaced in the ability of process engineers and physicians to protect workers against asbestos. Finally, deciding that asbestos was neither technologically nor economically essential, and was unsafe in use, Europe issued a Directive, to which Britain will conform, that will virtually ban it use throughout the Community by 2006.

Asbestos↗

PubMed2004

Evaluation of the size and type of free particulates collected from unused asbestos-containing brake components as related to potential for respirability.

BACKGROUND: Chrysotile asbestos has found multiple applications in the production of friction products. At one point it comprised 40-50% of the composition of brake linings thus generating the potential for the development of asbestos related diseases in millions of workers involved in vehicle repairs. While some attention has been given to the health status of workers involved in the handling of worn components, little has been given to the potential for exposure during the handling and fitting of new (unused) components as replacement parts. METHODS: Unused brake linings or brake shoes with attached linings from four different sources were gently rinsed with prefiltered water that was then collected on filters for analysis by Analytical Transmission Electron Microscope. RESULTS: Large numbers of chrysotile asbestos containing structures, the majority of respirable size, were present in each sample. CONCLUSIONS: We conclude that any manipulation of new asbestos containing brake components would be expected to yield free dust containing chrysotile asbestos of respirable size. That the vast majority of these fibers and particulates would not be counted as regulated fibers rendering assessment of potential exposures in the work place, based on data of Permissible Exposure Limits or Regulated Fibers, questionable.

Air Pollutants, Occupational↗

PubMed1982

Features of asbestos-exposed and unexposed mesothelioma.

Thirty-six histologically confirmed cases of pleural and peritoneal mesothelioma have been observed in a chest unit over a period of 53 months. The past asbestos exposure was assessed by a standardized questionnaire in all cases and the asbestos lung burden was determined by means of mineralogical analysis of lung-related biological specimens (sputum, bronchoalveolar lavage fluid, lung tissues) in 28 cases. The results of these two methods were found in good agreement. Past asbestos exposure has been definitely implicated in 17 cases and definitely eliminated in 10 cases. The results were inconclusive in other cases. The group with definite past asbestos exposure was different from the nonasbestos-exposed group by clinical, biological, pathological, and prognosis features that were analyzed. In cases without past asbestos exposure there were no other possible causative agents. Younger age and similar incidence in men and women suggest an environmental or natural disease.

Adult↗

PubMed1984

Lung function among asbestos cement factory workers: cross-sectional and longitudinal study.

Ventilatory capacity tests and standardized respiratory questionnaires were used in 1973 and in 1980 to measure the effect of mixed dust exposure in the asbestos cement industry on respiratory symptoms and lung function in 65 exposed workers and 30 controls (exposed to polyvinyl chloride but not to asbestos). Workers exposed to asbestos had 1) a higher prevalence of breathlessness and chest pain, and a higher incidence of breathlessness; 2) lower 1980 values of forced vital capacity (FVC) (0.27-0.83 liters) and forced expiratory volume in 1 sec (FEV1) (0.23-0.62 liters); and 3) a faster decline (nearly 40 ml/year) in FVC and FEV1 between 1973 and 1980. The FVC annual decrease was 52.5 ml in the subjects with more than 15 years since first asbestos exposure, whereas it was 24.3 ml in those with less than 15 years, suggesting a faster decline after 15 years of exposure. The effect of asbestos exposure and smoking habits was less than additive as regards pulmonary function.

Adult↗

PubMed1984

Decreased lung function in long-term asbestos cement workers: a cross-sectional study.

The effect on lung function of exposure in an asbestos cement plant was investigated in male workers, employed more than 10 years. The exposed group was selected to exclude subjects with pneumoconioses and ex-smokers and consisted of 77 smokers and 48 never-smokers. Referents were chosen from plants where asbestos had not been in use and restricted to those without X-ray signs of chest disease. The primary type of asbestos used was chrysotile and the general dust level in the two decades 1950-1970 seems to have been around 10 mg/m3 while the asbestos fiber concentration averaged 2 fibers/ml. The mean differences between exposed and referents were statistically significant for forced vital capacity and forced expiratory volume, -0.25 and -0.30 liters, respectively, after adjustment for age, height, tracheal area, and smoking category. No significant differences were detected between those with and without pleural plaques. Smokers and never-smokers were similarly affected. In conclusion, the group exposed to dust with comparatively low asbestos fiber concentration had a minor impairment of lung function, mainly due to obstructive changes.

Air Pollutants, Occupational↗

PubMed1985

Asbestos disease in sheet metal workers: the results of a proportional mortality analysis.

The results of a proportional mortality analysis of a cohort of sheet metal workers who have only intermittent exposure to asbestos demonstrates a significant excess of cancer at the three sites most frequently associated with asbestos: lung, colon and rectum, and the mesothelium. No excess nonmalignant respiratory disease was detected. These data strongly suggest that significant asbestos-related disease is present in populations with secondary exposure to asbestos and emphasize the importance of considering possible asbestos-related disease when treating patients with a history of employment in the construction industry.

Aged↗

PubMed1987

Past exposure to asbestos among active railroad workers.

Before the transition from steam- to diesel-powered locomotives during the 1950s certain railroad workers had the opportunity for significant occupational exposure to asbestos. Past studies have demonstrated that older workers with jobs associated with the repair of steam locomotives had the most exposure. To determine the prevalence of currently employed railroad workers with past asbestos exposure we surveyed 514 white male employees of an active US railroad by mail questionnaire. Twenty-one percent (50/242) of the workers 50 years old or greater had likely asbestos exposure compared to 3% (9/275) of the workers 49 years old or less (p less than .001). Fifteen (30%) of the 50 older workers with likely asbestos exposure had current job titles no longer suggestive of past exposure. The duration of exposure of these older active workers was short, (median = 3 years; range, 6 months to 15 years). A history of past asbestos exposure may still be obtained among active railroad workers with past railroad shop employment.

Adult↗

PubMed1988

Respiratory morbidity in workers exposed to asbestos in the primary manufacture of building materials.

Former employees (214) of a plant that manufactured asbestos-containing building materials (wallboard and acoustic tile) from 1958 through 1974 were screened for asbestos-related pulmonary disease. Results are presented on 182 union members whose names appeared on a 1966 seniority list in one of six departments believed to have had substantial asbestos exposure. The study population demonstrated a high frequency of pulmonary abnormalities often associated with asbestos exposure: low mean forced vital capacity percent of predicted (FVC % predicted), low mean forced expiratory volume at one second percent of predicted (FEV1 % predicted), presence of parenchymal abnormalities (40.1% with profusion scores of 1/0 or higher), and 30.5% with bilateral pleural abnormalities on chest roentgenograms. In addition, râles in two or more locations were found in 22.8% on examination of the chest, 30.6% gave a history of chronic bronchitis, and 34.8% of dyspnea grade two or higher. Calculated asbestos exposure scores, based upon participant recall, were not found to be associated with these abnormalities. The abnormal findings were not adequately explained by potential confounders such as cigarette smoking. Other notable findings in this study include the presence of smoking-adjusted decrements in pulmonary function associated with moderate profusion scores (i.e., 1/0 and 1/1) and the presence of a substantial degree of obstructive lung disease (19.2%) in this population.

Adult↗

PubMed1991

Radiographic abnormalities in asbestos insulators: effects of duration from onset of exposure and smoking. Relationships of dyspnea with parenchymal and pleural fibrosis.

Chest radiographs and spirometry were evaluated in 2,907 active and retired asbestos insulators; most (86.8%) had greater than or equal to 30 years from onset of asbestos exposure. Testing was performed in 19 cities in the United States during 1981-1983. Complete demographic, smoking, clinical, and radiologic data were obtained for 2,790 workers. This is the largest single group of insulators that has been studied. Five hundred forty-eight (19.7%) had never smoked cigarettes, 942 (33.9%) were current cigarette smokers, and 1,300 (46.6%) were ex-smokers. Only 439 (15.7%) workers had no radiographic evidence of asbestos-related disease (normal chest X-ray); 668 (23.9%) had pleural fibrosis only, 325 (11.6%) had parenchymal fibrosis alone, and 1,358 (48.7%) had both parenchymal and pleural fibrosis. The prevalence of radiographic parenchymal changes increased significantly (p less than .001) from 38.6% (DURONSET less than 30 years) to 70% (greater than or equal to 40 years). For pleural changes the comparative prevalences were 55% and 82%. Those with no history of cigarette smoking were more likely to have normal films than those with a history of smoking (19.2% versus 14.4% for current smokers and 15.2% among ex-smokers), and were less likely to have parenchymal fibrosis (44.5% versus 69.7% for current smokers and 60.2% of ex-smokers). Dyspnea, MRC grade 3 and higher, was more prevalent when pleural fibrosis was associated with interstitial pulmonary fibrosis (at all profusion levels of small opacities) than when pleural fibrosis was absent. Logistic regression analysis of factors contributing to such dyspnea showed that the presence of combined parenchymal and pleural abnormalities was a significant explanatory variable, in addition to age, smoking, and body mass (Quetelet index); the presence of parenchymal changes only or of pleural changes only, as factors contributing to dyspnea, did not reach the level of statistical significance in the regression analysis. The results of these examinations show that pleural fibrosis is a frequent finding in asbestos-exposed groups with long-term follow-up and that its functional significance is not negligible. The contribution of cigarette smoking to prevalence and severity of interstitial fibrosis is an additional reason for smoking cessation among asbestos-exposed individuals.

Adult↗

PubMed1991

Difficulties of attribution of effect in workers exposed to fiberglass and asbestos.

Man-made mineral fibers have many properties of asbestos that raise concern about their safety. We studied 175 fiberglass production workers, using chest radiographs, measurement of total lung capacity, chest examinations, and occupational and medical histories. Pulmonary volumes and flows were calculated as percent of predicted, adjusted for height, age, ethnicity, and cigarette smoking. Thirty-one men with radiographically evident small irregular opacities of profusion of 1/0 or greater and/or pleural abnormalities were observed. Eight of 38 men with such changes said they had been exposed only to fiberglass; the other 23 with radiologically detectable pleural and/or pulmonary changes were among the 137 whose histories indicated that they had been exposed to asbestos and to fiberglass. Pulmonary function measurements as group means were reduced in the 175: FVC was 94.8% predicted, FEV1 was 91.3% predicted, FEF25-75 was 80.7% predicted, FEF75-85 was 73.1% predicted and FEV1/FVC was 0.73. Total lung capacity (TLC) was elevated to 114.2% predicted (mean) and RV/TLC (mean 0.46) was also elevated. Although only 78% of fiberglass production workers gave histories of asbestos exposure, all had shared the air in a manufacturing plant where ovens insulated with asbestos were continuously cleaned, repaired, dismantled, and rebuilt. It appears that attribution of the effects of their exposure to fiberglass could not be estimated independently of the effects of asbestos exposure.

Adult↗

PubMed1992

T-cell alveolitis in lung lavage of asbestos-exposed subjects.

In sarcoidosis and idiopathic pulmonary fibrosis, it has been reported that lymphocyte proportions in lung lavage predict the subsequent clinical course. Recent evidence has suggested that lymphocytes are important in the alveolitis of asbestosis. We hypothesized that a greater relative proportion of T-lymphocytes in lung lavage of asbestos-exposed subjects is associated with immune activation and may predict the subsequent clinical course. We assessed lymphocyte subsets in lung lavage and peripheral blood (PB) of 97 asbestos-exposed subjects and 10 unexposed normal, using flow cytometry analysis of monoclonal antibody-treated cells. T-cell alveolitis was defined as follows: [%lymphocytes in lavage x %CD3 in lavage] greater than 2 SD above that product in normals. Eighteen subjects had T-cell alveolitis (group 1) and 79 did not (group 2). There were no significant differences between the groups in age, smoking status, duration of exposure, lung function results, or frequency of plaques or profusion greater than or equal to 1/0. Percent CD2 was higher in lavage of group 1 compared with group 2. There was a trend for higher %Ia in lavage of group 1 compared with group 2. These results identify a subgroup of asbestos-exposed subjects with T-cell alveolitis but no present excess of asbestos-related disease who may be at risk for future asbestos-related disease.

Adult↗

PubMed1992

Blood superoxide dismutase and plasma malondialdehyde among workers exposed to asbestos.

Blood superoxide dismutase (SOD) and plasma malondialdehyde (MDA) (an indicator of lipid peroxidation [LPO]) were determined in 97 randomly selected asbestos exposed workers (age range: 25-60 years, mean duration of exposures 19.8 +/- 8.3 years) and in 42 healthy male controls. MDA, SOD, and MDA/SOD ratio in asbestos exposed workers were significantly higher than in controls. Among both the controls and exposed workers neither age nor smoking was related to SOD or MDA levels. SOD was significantly positively correlated with MDA among the exposed workers. Such correlation was not observed among the controls. SOD but not MDA was significantly positively correlated with the duration of exposure to asbestos. Mean levels of SOD or MDA in exposed workers with radiographic signs of lung fibrosis or pleural thickening did not differ significantly from those without such signs. The results confirm the possible involvement of LPO and development of anti-oxidant mechanism(s) of prolonged exposure to asbestos in humans. However, SOD seems not to be the essential anti-asbestos-induced LPO. Relation between these factors and lung fibrosis is still unclear.

Adult↗

PubMed1992

Accelerated loss of lung function and alveolitis in a longitudinal study of non-smoking individuals with occupational exposure to asbestos.

Long-term asbestos workers who insulate pipes and boilers may develop interstitial lung disease associated with loss of lung function. To quantitate annual loss of lung function, 77 individuals with chest X-rays greater than or equal to 1/0 ILO category who were life-long non-smokers or ex-smokers for greater than 5 years were evaluated. Study parameters included pulmonary function tests and bronchoalveolar lavage for a mean of 3 visits over 30 +/- 2 months. The study participants were 56 +/- 1 years old and had 31 +/- 1 years' occupational exposure to asbestos. At the first visit, multiple regression analysis revealed significant associations between rales or radiographic opacities and VC, FEV1, and total lung capacity; significant associations were also found between neutrophils/ml lavage fluid with FEV1 and diffusing capacity (all p less than 0.05). Annual declines for the asbestos-exposed were VC -92 +/- 28 ml/yr and FEV1 -66 +/- 21 ml/yr. Declines in VC and FEV1 were less in those with reduced lung function at the initial visit. There were no significant associations between any of the annual declines and cells recovered by bronchoalveolar lavage. Compared to other asbestos-exposed cohorts followed longitudinally, asbestos insulators with radiographs greater than or equal to 1/0 and exposure greater than or equal to 20 years have larger rates of FVC and FEV1 decline for both non-smokers and ex-smokers.

Asbestos↗

PubMed1992

Lung function and exposure to asbestos among vehicle mechanics.

Vehicle mechanics (n = 99) exposed to asbestos (annual median value 0.08 f/ml), and local controls (n = 83) not occupationally exposed to asbestos were studied with regard to symptoms and pulmonary function. The inclusion criteria to participate in this study was an age of at least 40 years with no known exposure to lung irritating agents, and for the exposed subjects, more than 15 years occupational exposure to asbestos with at least 20 years from the first exposure. The subjects were studied during identical conditions by means of dynamic and static spirometry, single breath wash-out with nitrogen (N2) and carbon monoxide (CO). The median for cumulative exposure of asbestos during the entire work life among the studied mechanics was 2.3 f*y/ml. The mechanics had reduced transfer factor (TLCO), after adjustment for age, height, and smoking category. A significant dose-response relationship was noted between the cumulative exposure of asbestos and CV%. The findings suggest a slight influence of small airways and alveoli. The evaluation of the prognostic significance of this requires a longitudinal study.

Adult↗

PubMed1993

Asbestos screening and education programs for building and construction trades unions.

Worker notification involves informing current and past employees of their risk of disease. It also involves suggesting ways to reduce their risks. The asbestos screening and education programs designed for the building and construction trades unions were a national multisite effort that focused on improving the health of eligible union members and retirees at high risk of developing asbestos-related disease. The asbestos screening and education programs were made available to "high-risk," asbestos-exposed local union members through the efforts of a number of international unions, including the International Union of Elevator Constructors and the Laborers' International Union of North America--both affiliates of the Building and Construction Trades Department, AFL-CIO. Consultation and program assistance in developing and implementing these programs were provided by the Occupational Health Foundation, a labor-sponsored, nonprofit organization with a multidisciplinary safety and health staff. Program components included identification of "high-risk" individuals, notification of risk, education, medical screening, legal referral, and various support services. Community-based physicians and/or physician-staffed mobile testing units provided services on a contractual basis according to a standardized medical protocol. Between 1988 and 1991, 2,136 union members and retirees from 89 local unions affiliated with the Elevator Constructors or the Laborers were screened in 59 regional programs. A general description and historical perspective are offered concerning program implementation, integration into existing union infrastructures. Emphasis is placed on the role of the unions in advancing members' interests when dealing with the health and socioeconomic implications of asbestos-related disease.

Asbestos↗