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 1,567 records · Page 87Linked to original sources

PubMed1981

Mesothelioma relative to asbestos, radiation, and methylcholanthrene.

The carcinogenicity of chrysotile asbestos fibers (Canadian and Rhodesian) for the mesothelium of pleura and peritoneum of NEDH rats was explored by injection of 2 mg of asbestos fibers suspended in saline intratracheally, intrapleurally, or intraperitoneally, with or without ancillary radiation treatment (1,000 rad to the whole body of parabiont rats or 2,000 rad to the right thorax of single rats), or alternatively, by injection of asbestos plus 1 mg of 3-methylcholanthrene. A highly significant incidence of mesothelioma (3.8%) was noted in 159 rats treated with asbestos alone, as compared with 0.1% in 1,417 control rats. Additional treatment with radiation or 3-methylcholanthrene increased this incidence to 11.8% and 25.5%, respectively, the latter increase alone being significant at the .01 level of probability.

Animals↗

PubMed1980

[Investigations and review of literature relating to carcinogenesis. I. Communication: Cancer from asbestos, schistosomiasis, and cicatrization (author's transl)].

This review covers the following aspects: Cancer associated with asbestos and other fibers: Epidemiology. - Cancer types and location (mesothelioma; bronchogenic carcinoma; cancer of the upper respiratory tract; abdominal cancer). - Experimental asbestos cancer. - Other kinds of fibers and cancer (wool and cotton; glass; talc; others). - Cancer determining or influencing factors (individual predisposition; species susceptibility; type of material; shape and size of fibers; smoking). - Preneoplastic signs in man (fibrosis; ferruginous bodies; pleural plaques; milky spots). - Preneoplastic development in animals. - Fiber effects on cell cultures (macrophages; fibroblasts). Cancer associated with schistosomiasis: Epidemiology. - Patient age and cancer latency. - Pathology. - Foreign body reaction and preneoplastic development. Scar cancer. Foreign body cancer: In man. - Experimental (species differences in susceptibility; individual genetic differences in tumor incidence and latency; influence of sex, age, nutrition; tumor histopathology and ultrastructure; tumor growth, invasiveness, metastases, transplantability, immunology; search for tumor viruses). - Properties of foreign body materials in relation to tumorigenicity (chemical and physical properties; size and shape; surface properties; porosity). - Investigations and findings concerning the origin of foreign body sarcomas (the foreign body reaction; search for foci of tumor origin; an analytical method; monoclonal tumor origin; heterogenicity of carcinogenic events; surface dependency; identification of originator cells; time and location of the emergence of tumor originator cells; the carcinogenic initiation event; surface-independent and dependent preneoplastic maturation; the carcinogenic role of the foreign body). - Earlier hypotheses and theories in the light of new experimental findings. The results of experimental foreign body tumorigenesis in relation to foreign body-, asbestos-, schistosomiasis-, and scar-cancer in man. (Common factors of promotion; differences regarding induction mechanisms, cells of origin, latencies, frequencies; immune defense). Consequences for prevention: Asbestos cancer. - Fiber cancer. - Schistosomiasis cancer. - Foreign body cancer (assessing the peril in man; testing of materials for carcinogenicity; recommendations).

Animals↗

PubMed1978

Production of antibody toward asbestos.

Unlike normal rabbit control globulins, experimental globulins from rabbits injected with BSA-coated asbestos were found to bind with asbestos. One evidence of such binding is a decreased rate of sedimentation of asbestos in solution. Other evidence has been obtained in experiments with fluorescein-labelled reagents. These results are taken to be indicative of the presence of anti-asbestos antibody in the experimental globulins.

Animals↗

PubMed1982

Smoking and duration of asbestos exposure in the production of functional and roentgenographic abnormalities in shipyard workers.

Functional and roentgenographic abnormalities in 131 asbestos-exposed shipyard workers were assessed in terms of duration of asbestos exposure and smoking history to determine the relative contributions of these factors. Both exposure and smoking contributed to the frequency of abnormalities in FEV1 and FVC. In contrast, airways obstruction (FEV1/FVC less than 70%) was unrelated to exposure but correlated closely with smoking. Abnormalities in DLCO were minimally associated with asbestos exposure, but were strongly related to smoking history, suggesting that diffusion impairment in these workers is more likely to be related to smoking and emphysema than to interstitial disease. Significant roentgenographic pleural abnormalities were associated with both duration of exposure and smoking. Interstitial disease did not correlate with exposure and was only mildly associated with smoking. Smoking contributes to many of the functional and roentgenographic abnormalities in asbestos-exposed workers.

Adult↗

PubMed1980

Clinical and radiological observations on asbestos-related pathology.

The papers in this session, which are summarized briefly, do not cover the wide range of radiological and clinical problems resulting from inhalation of asbestos dust. Pleural effusions are found in persons exposed occupationally to asbestos, even in the absence of asbestosis, but they are difficult to attribute to such exposure. Asbestosis of the lung shows no striking symptoms and can also be diagnosed only after all other possibilities have been excluded. There are no convincing or striking morphological peculiarities that suggest that an 'asbestos lung cancer' exists. Mesotheliomas of the pleura and of the peritoneum are usually resistant to therapy of any kind, although several possibilities are discussed. Radiological surveillance is presented as being still the most effective and reliable method for medical surveillance of asbestos workers. Circumscribed pleural thickening is benign but a good indicator of exposure to mineral dusts. Diffuse pleural thickening occurs frequently in nonexposed groups and cannot, therefore, be used as an indication of exposure; however, it cannot yet be ruled out as being significant epidemiologically.

Adult↗

PubMed1980

Asbestos: scientific basis for environmental control of fibres.

Any review of the scientific evidence on which public policy is based must commence with a cautionary statement about the quality of the available data both about dust and about asbestos-related disease. Attention is drawn to some of the main problems. It is concluded that, in spite of their shortcomings, the data are sufficiently consistent to be useful in relation to some aspects of the problem of environmental control of the asbestos hazard. The question whether or not there is a threshold dose of fibre below which no biological effect occurs is of considerable importance in framing public policy. The evidence concerning the existence or otherwise of a threshold in relation to the different asbestos-related diseases is summarized. A summary is also given of the evidence about the shape of the dose-response curves for asbestos-related diseases in man. The paper concludes with a note on how scientific data may be summarized in a manner which may be helpful in formulating public policy with regard to a control limit.

Air↗

PubMed1980

Estimation of exposure to asbestos-cement dust on building sites.

In the Federal Republic of Germany, about 1.2 million tons of asbestos are handled on building sites, for example, by roofers, carpenters and ventilation fitters. The objective of this study was to determine both the exposure to dust during the handling of asbestos-cement products on building sites and the possible resulting fibrogenic health hazard. In order to assess the tumour risk, this cross-sectional study should be enlarged to a longitudinal study. Dust measurements were made on about 40 building sites with four static and four personal dust samplers and a Tyndallometer. Evaluation was performed by infrared spectrography and light and scanning electron microscopy. Peak concentrations of more than 100 fibres/ml of length greater than 5 micrometers or about 80 mg/m3 fine dust were observed in the vicinity of the grinding machine. The asbestos content of the fine dust was about 10%. Scanning electron microscopy showed a wide variation of fibre lengths and diameters; a large proportion of fibres with diameters below 0.2 micrometers was found. Long-term, mean values and confidence intervals of the concentration of fine dust were calculated from the measurements. For example, the mean fine dust mass concentrations for roofers cutting corners of asbestos-cement sheets with the grinding machine amounted to 2.2 mg/m3 when the cutting was done in the open air at a fixed location. When cutting was performed on the roof, the mean fine dust mass concentration amounted to 1.8 mg/m3.

Air Pollutants↗

PubMed1980

Morphological, morphometric and x-ray microanalytical studies on lung tissue of rats exposed to chrysotile asbestos in inhalation chambres.

Rats were exposed to NIEHS short-range and to NIEHS intermediate-range chrysotile fibres for periods varying from one hour to one year. Following the exposures, the lungs from each animal were fixed by intratracheal instillation of 2% glutaraldehyde. Studies of fibre location following short exposure periods suggest that inhaled asbestos reaches the connective tissue compartment of the lung by passing through epithelial cells. X-ray energy microanalytical techniques were used to determine the magnesium to silicon ratios in fibres in situ. Inhaled particles were found to have decreased Mg:Si ratios if they were located in the interstitium, and many of the particles located within the alveolar airspaces had an even more marked decrease in the Mg:Si ratio. Morphometric techniques were used to quantitate structural changes occurring in the asbestos-treated animals. After three months of exposure, both types of chrysotile asbestos fibres caused similar increases in the volume of the alveolar epithelium, the interstitium and in alveolar macrophages. After twelve months of exposure, greater lung injury, involving both the alveolar epithelium and the interstitium, was found in animals exposed to the intermediate-range fibres. Physiological studies done after one year of asbestos exposure demonstrated a fall in total lung capacity and in vital capacity, which was most marked in the animals exposed to the intermediate-range fibres. These studies suggest that both classes of chrysotile fibres cause lung injury but that long fibres have the greater toxicity.

Animals↗

PubMed1980

Pretumorous lesions and lung and pleural tumours induced by asbestos in rats, Syrian golden hamsters and Macaca mulatta (rhesus) monkeys.

Asbestos samples were injected into the right pleural cavity of random-bred rats (20 mg thrice monthly). Milled commercial chrysotile induced pleural mesotheliomas in 65.5%, its dust in 46.3%, milled synthetic chrysotile in 2.4%, milled commercial magnesia-arphvedsonite in 77.1%, milled commercial anthophyllite in 41.4%, its dust in 64.9% and milled synthetic hydroxyamphibole in 54.5%. Intratracheal injections (10 mg twice monthly) of milled commercial chrysotile into Syrian golden hamsters induced lung tumours in 63% (malignant in 44.4%, benign in 18.5%), synthetic chrysotile in 23% (malignant in 7.7%, benign in 15.3%), commercial magnesia-arphvedsonite (5 mg twice monthly) in 80.8% (malignant in 46.2%, benign in 34.6%) and synthetic hydroxyamphibole (5 mg twice monthly) in 63.4% (malignant in 19.2%, benign in 44.2%). Benzo[a]pyrene adsorbed or added to asbestos dust stimulated asbestos-induced lung carcinogenesis in rats but had no influence on pleural carcinogenesis. Pretumorous lesions were found in lung tissue and in pleural mesothelium in all experiments in rats, hamsters and monkeys after instillations of asbestos into the lungs and pleural cavity. The morphological picture of the pretumorous lesions and tumours was similar in all experiments. Diffuse and focal hyperplasia and proliferation of epithelium-like and fibroblast-like mesothelial cells were observed. Benign (adenoma-like, fibrous) and malignant (carcinoma-like, sarcoma-like, mixed) mesotheliomas were also found.

Adenocarcinoma↗

PubMed1981

Psychological aspects of asbestos-related mesothelioma and knowledge of high risk for cancer.

Ten patients with a diagnosis of malignant mesothelioma were assessed for history of asbestos exposure, acquisition of and reactions to risk information, smoking behavior, and feelings about their disease and the asbestos industry. Mean age was 59 years; median span of time from diagnosis to interview was 10 months. Only two of seven patients with direct occupational asbestos exposure acquired risk information from a professional source. Lack of concern and denial are the reactions reported most frequently to risk information. Behavioral findings support the reported attitudinal reactions. None of the eight smokers in the sample stopped smoking after receiving increased risk information. Not a single patient increased his visits to a physician. Patients commonly expressed feelings of of being unlucky in reactions to the disease. Seven of the ten patients denied any feelings of anger toward the asbestos industry. These preliminary findings suggest the need for better information and education of high risk individuals.

Asbestos↗

PubMedDate not supplied

Asbestos fibers in wines: relation to filtration process.

Asbestos fibers have been counted, using the transmission electron microscope, in 42 wines from France and abroad. 15 samples were found to be significantly positive for chrysotile asbestos. Concentrations were in the range of 2 to 60 x 10(6) fibers/liter. Technical inquiries have shown that the asbestos content of the wines was related to the process by which they were filtered. On the other side, it has been tested that if one abolished the use of asbestos for filtering wines, they would not be altered from the oenological point of view.

Asbestos↗

PubMedDate not supplied

[The diffusion of information on the carcinogenicity of asbestos in the Italian scientific community before 1965].

The spreading of information on asbestos carcinogenicity within the Italian scientific community before 1965. The paper deals with the development of recognition of asbestos carcinogenicity within the Italian scientific community. This development was difficult in Italy as in other countries. Articles and other papers in handbooks and congress proceedings, by Italian authors, published in the period 1934-1965, were considered. The first cases of lung cancer in Italian workers exposed to asbestos were observed in 1955-56, the first cases of malignant mesothelioma in 1965. The cases observed were very few, but knowledge on asbestos carcinogenicity became widespread within the Italian scientific community during the fifties (from 1953 on wards) with the publication of several handbooks of occupational medicine.

Asbestos↗

PubMed1995

Inherited GSTM1 and NAT2 defects as concurrent risk modifiers in asbestos-related human malignant mesothelioma.

Besides asbestos exposure, the factors that determine susceptibility to malignant mesothelioma are unknown. We evaluated the risk of GSTM1 null genotype and slow acetylation-associated NAT2 genotype for malignant mesothelioma in relation to asbestos exposure. Both the GSTM1 null genotype and the NAT2 slow acetylator genotype placed individuals at about 2-fold increased risk of developing malignant mesothelioma [odds ratio (OR) = 1.8, 95% confidence interval (CI) = 1.0-3.5 and OR = 2.1, 95% CI = 1.1-4.1, for the GSTM1 and NAT2 genes, respectively]. When the patients were divided into low/moderate and high exposure groups according to their asbestos exposure histories, the effect of the at-risk genotypes was mostly attributable to the high exposure groups (OR = 2.3, 95% CI = 1.0-5.6 and OR = 3.7, 95% CI = 1.3-10.2, for the GSTM1 and NAT2 genes, respectively). The individuals with combined GSTM1 and NAT2 defects had about a 4-fold risk of developing malignant mesothelioma compared to those with the GSTM1 gene and NAT2 fast acetylator genotype (OR = 3.6; 95% CI = 1.3-9.6). Moreover, the risk among subjects highly exposed to asbestos with the double at-risk genotype was more than 7-fold greater compared to those with the more beneficial genotypes of both GSTM1 and NAT2 genes (OR = 7.4; 95% CI = 1.6-34.0).

Adult↗

PubMed1995

[Asbestos-related mesotheliomas in housewives from indoor air pollution].

We report five cases of pleural mesothelioma in housewives, that are attributed to inhalative household-contact with asbestos. An occupational history of asbestos exposure could not be revealed. A causal relationship between the fatal disease and the inhalative house-hold-contact with asbestos was established based on the cleaning of asbestos contaminated work-clothes of the husbands.

Aged↗

PubMed1994

[The role of pulmonary epithelial cells in lung cellular reaction to asbestos exposure].

The damage of pulmonary alveolar epithelial cells occurs in many inflammatory conditions caused by various agents, e.g. asbestos, that involve interstitial lung disease in experimental animals and in humans. After exposure to asbestos alveolar epithelial cells contain significant amount of asbestos fibers and show histologic changes which indicate a marked epithelial injury. The alveolar epithelial injury is manifested by swelling, debris and patchy necrosis of type I cells partly detached from its basement membrane. Besides, regenerative hyperplasia of type II pneumocytes with ultrastructurally cisternal dilation of the rough endoplastic reticulum and significantly greater number of lamellar bodies are found. Following the cessation of exposure, epithelial cells are cleared out of asbestos fibers and return to the normal condition. These data provide insight into pathogenesis of diffuse lung disease and the role of alveolar cells in early and late phases of asbestosis.

Animals↗

PubMedDate not supplied

Asbestos content of bronchoalveolar lavage fluid. A comparison of light and scanning electron microscopic analysis.

We studied the asbestos content of bronchoalveolar lavage fluid (BALF) from 9 patients with asbestosis, 17 asbestos exposed but without asbestosis, 15 with idiopathic pulmonary fibrosis (IPF) and 9 nonexposed volunteers. The cellular lavage pellet was digested and filtered for asbestos body (AB) quantification by light microscopy (LM) and analysis of numbers and types of uncoated fibers (UF) by scanning electron microscopy (SEM) and energy dispersive x-ray analysis. BALF of asbestosis patients had significantly higher AB content than that of the combined IPF and volunteer groups. The UF content as determined by SEM was similar in all four groups. Commercial amphiboles (amosite or crocidolite) were identified more frequently in BALF from patients with asbestosis than from the other groups. ABs were detected by SEM only in highly exposed individuals. We conclude that the findings of > 1 AB per 10(6) cells or 1 AB/mL BALF by LM and of ABs or commercial amphibole fibers by SEM are indicative of considerable exposure to asbestos in the majority of cases.

Adult↗

PubMed1993

[Remote effects in the mutagenic action of chrysotile asbestos and zeolite dusts in vivo].

It was proposed that there are a generalized mutagenic actions of chrysotile-asbestos fibers and zeolite particles in vivo. Chrysotile-asbestos fibers and different species zeolite particles in doses 50 mg/kg, intraperitoneally, increased the levels of damaged chromosomes not only in peritoneal cells, but also in bone marrow of C57BL/6 mice. Cytogenetic effect of chrysotile-asbestos does not depends on the time exposure of animals with mutagenic factor. In four weeks followed after administration chrysotile-asbestos fibers there were revealed 19-22% peritoneal cells with damaged chromosomes and 3.2-4.4% aberrant cells of bone marrow. Cytogenetic effect of zeolite particles was observed on 14-28 days after the administration, with peaks at 35.6% in peritoneal and 3.6-4.2% in bone marrow cells. Our data indicate the mutagenic action is realised as in cells contacted with dusts as in cells of other tissues. Probably, these effects are mediated by products of lipid peroxidation.

Animals↗

PubMed1994

The beta-carotene and retinol efficacy trial (CARET) for chemoprevention of lung cancer in high risk populations: smokers and asbestos-exposed workers.

CARET is a multicenter, two-armed, double-masked randomized chemoprevention trial in Seattle, Portland, San Francisco, Baltimore, Connecticut, and Irvine, to test whether oral administration of beta-carotene (30 mg/day) plus retinyl palmitate (25,000 IU/day) can decrease the incidence of lung cancer in high risk populations, namely, heavy smokers and asbestos-exposed workers. The intervention combines the antioxidant action of beta-carotene and the tumor suppressor mechanism of vitamin A. As of April 30, 1993, CARET had randomized 1,845 participants in the 1985-1988 pilot phase plus 13,260 "efficacy" participants since 1989; of these, 4,000 are asbestos-exposed males and 11,105 are smokers and former smokers (44% female). Accrual is complete everywhere except Irvine, which was the last center added (1991), and the safety profile of the regimen to date has been excellent. With 14,420 smokers, 4,010 asbestos-exposed participants, and 114,100 person-years through February 1998, we expect CARET to be capable of detecting a 23% reduction in lung cancer incidence in the two populations combined and 27, 49, 32, and 35% reductions in the smokers, female smokers, male smokers, and asbestos-exposed subgroups, respectively. CARET is highly complementary to the alpha-tocopherol-beta-carotene study in Finland and the Harvard Physicians Health Study (beta-carotene alone) in the National Cancer Institute portfolio of major cancer chemoprevention trials.

Aged↗