Fibrosis In Workers Research Articles

Assessment of the lung tissue fibrosis in workers exposed to silica-hazardous dust for a long time

Introduction. Silicosis is the most common and severe type of pneumoconiosis caused by inhalation of dust containing more than 10% of crystalline silica in the occupational setting. The chest X-ray plays a decisive role in the diagnosis of the disease.
 The purpose of our work was to establish lung tissue fibrosis in industrial workers suffering from silicosis.
 Materials and methods. In 2015–2022, ten patients with silicosis, employed at a Ural refractory manufacturing plant as press operators (Group 1) for the average of 17.23 ± 4.31 years, were examined at the Occupational Health Clinic of the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers. The comparison group (Group 2) included 34 press operators without pneumoconiosis who had worked for more than 10 years in hazardous working conditions. The control group (Group 3) consisted of 32 people of different occupations unexposed to industrial dusts. All the subjects were matched by gender (male) and age (50.7 ± 5.25 years). Lung tissue fibrosis was measured by multislice computed tomography using a GE OPTIMA 660 128 Slice CT Scanner with accessories, GE HealthCare Japan, manufactured in 2012. The data were then analyzed in Statistica for Windows 7.
 Results. We established a decrease in tissue fibrosis in the apexes and inferior lobes of both lungs and an increase in the fibrosis in groups of target lymph nodes (11–14R, 2L, 10L) in the silicosis cases, and an increase in Hounsfield units in target groups of lymph nodes (2R, 4R, 10R, 11–14R, 2L, 11–14L) in the comparison group.
 Limitations. The study includes only workers engaged in refractory manufacturing with over 10 years of exposure to silica. For CT lung densitometry, the limitation is the permissible radiation dose of less than 5 mSv per year.
 Conclusion. The results of CT densitometry of the lungs and targeted groups of lymph nodes demonstrate its high efficiency in the quantitative assessment 
 of dust-related disorders in patients with silicosis and in experienced workers occupationally exposed to crystalline silica.

Influence exerted by somatic pathology on risks of occupational lung fibrosis in workers employed at refractory production

Occupational lungs and bronchial pathology occurs not only under exposure to dusts, their aerosol structure and aggression, but also depends on individual properties of a body. The latter can determine either increased body resistance or susceptibility to occupational pathology occurrence. Our research goal was to determine influence exerted by somatic pathology on occupational lung fibrosis occurrence as well as to estimate prevalence of risk factors for cardiovascular and metabolic pathology occurrence in workers employed at refractory production. At the first stage 449 workers employed at refractory production were examined at a periodical medical examination (PME). Patients’ average age was 41.59±0.45 and average work experience was 14.47±0.39 years. At the second stage 172 workers were examined at an occupational pathology center; 75 out of them were workers who had silicosis and were included into the test group and the remaining 97 workers didn’t have any occupational pathology and were included into the reference group. Both groups were comparable as per sex (p = 0.0052) and work experience under exposure to dusts (р = 0.862). Workers examined at a PME most frequently had overweight and obesity (68 %). Arterial hypertension (AH) prevalence amounted to 19.5%; carbohydrate metabolism disorders, 19.8 %; 48.1 % workers had hypercholesterolemia. Patients with silicosis had certain disorders significantly more frequently than workers with long work experience but without any occupational pathologies; those disorders were AH, cardiac muscle hypertrophy in the left ventricle, ischemic heart disease, heart rate disorders, as well as mixed (obstructive and restrictive) breath mechanics disorders. We determined some factors that authentically produced certain effects on occupational lung fibrosis occurrence in workers employed at refractory production. Median time of silicosis occurrence was significantly shorter (by 11.5 years) among workers with severe AH, arrhythmia (by 13 years), lower hemoglobin in blood (by 11.5 years). Besides, silicosis occurred significantly earlier (by 10.8) among women than among men.

Progress in study on intervention of silica-induced pulmonary fibrosis with the exosomes released from mesenchymal stem cells

Pneumoconiosis is an occupational disease which seriously endangers the health of workers exposed to dust. Silica is regarded as the most serious cause of pneumoconiosis because it can cause diffuse pulmonary fibrosis in workers' lung tissue. Mesenchymal stem cells (MSCs) are adult stem cells with multiple differentiation potential. As member of extracellular vesicles family, exosomes can be secreted from MSCs to regulate and intervene tumorigenesis, cardiovascular disease, immune system disorder and tissue damage disease. This article reviews the experimental results in the field of intervention of MSCs and its exosomes in silicosis research in recent years, which plays an important role in indicating direction in the future research on the mechanism and function of MSCs exosomes in the therapy of silica-induced pulmonary fibrosis.

Morphological features of pulmonary fibrosis in workers occupationally exposed to alpha radiation

Purpose: The article reports on a comparative analysis of biological specimens of lung tissues collected from workers with pulmonary fibrosis induced by internal exposure to plutonium alpha-particles (plutonium-induced pulmonary fibrosis [PuPF]) and with etiologically different pulmonary fibrosis (non-PuPF) that developed as an outcome of a chronic obstructive pulmonary disease (COPD).Materials and methods: To perform histological examinations, lung tissues were sampled during autopsy. Six samples of various lung regions (the apical region, the lingula of the left lung and the inferior lobe) were collected from each donor. The resected tissue samples were fixed in 10% neutral-buffered formalin during 24 h and embedded into paraffin blocks (FFPE). FFPE blocks with lung tissue specimens collected from 56 workers with PuPF, 34 workers with non-PuPF and 35 workers without any lung disease were used in the study. To perform microscopic examination, lung tissue specimens were hematoxylin and eosin stained. To examine the connective-tissue scaffold of lung stroma and identify foci of pulmonary fibrosis, the cut sections of paraffin blocks were stained by Van Gizon’s method (to assess the total volume of fibrosis-affected tissues), Gomori’s technique (to define the reticular scaffold of lung stroma) and Weigert’s technique (to examine elastic fibers). Morphological patterns of all biological specimens were studied using immunohistochemistry. To fit the empirical data, the Weibull’s model was used.Results and conclusions: The study found qualitative and quantitative morphological features specific for PuPF compared to non-PuPF. The study demonstrated that hyper-production of collagen type V plays a key role in PuPF. The collagen type V content in fibrotic foci in lung tissue specimens from workers with PuPF was found to be increased.

CARDIOVASCULAR AND METABOLIC DISORDERS ASSOCIATED WITH OCCUPATIONAL LUNG FIBROSIS IN EMPLOYEES EXPOSED TO THE DUST AT THE WORKPLACE

Introduction. The attribution of certain medical conditions in industrial workers to hazardous exposures at the workplace remains a challenging issue of occupational health. Material and methods. In order to identify cardiovascular conditions associated with occupational lung diseases in workers exposed to fibrogenic dust, we conducted a medical check-up examination of individuals employed in refractory production and asbestos industry. The main group consisted of the patients with a confirmed diagnosis of lung fibrosis (asbestosis, silicosis); the reference group was age- and tenure-matched workers without occupational fibrosis. Results. We established a significantly higher prevalence of arterial hypertension, left ventricular hypertrophy, sinus tachycardia, obesity, hypertriglyceridemia and impaired fasting glycemia in workers with silicosis and asbestosis if compared to those without work-related diseases. Based on the relative risk and attributable fraction estimates, we assume there is moderate occupational causation for arterial hypertension and a strong one for left ventricular hypertrophy, sinus tachycardia, and obesity. Very strong causation was found between occupational exposure to fibrogenic dust and carbohydrate metabolism disorders. High-stage hypertension, dyslipidemia and left ventricular hypertrophy were found to have a statistically significant impact on the timing of silicosis. Whereas high-stage hypertension, coronary artery disease, left ventricular hypertrophy and obesity were found to impact the timing of asbestosis. Conclusion. Cardiovascular and metabolic disorders are statistically more occurrent in workers with silicosis or asbestosis. Therefore, the disease can be regarded as work-related. We established cardiovascular and metabolic disorders to have a statistically significant impact on the timing of silicosis and asbestosis. Therefore, a timely CVD prophylaxis could reduce the risk of occupational lung fibrosis in workers exposed to fibrogenic dust.

Progressive massive fibrosis in workers outside the coal industry: A case series from New Mexico

Progressive massive fibrosis in workers outside the coal industry: A case series from New Mexico

Pulmonary Fibrosis in Workers Exposed to Non-asbestiform Tremolite Asbestos Minerals

Studies of the health effects of non-asbestiform asbestos minerals remain inconclusive. Nephrite is a type of non-asbestiform tremolite mineral. We assessed the risk for pulmonary fibrosis in workers who process nephrite. A cross-sectional study that included 344 stone workers and their families was undertaken in Taiwan in 2010. The diagnostic criteria for pulmonary fibrosis included (1) radiographic fibrosis profusion of 1/1 or greater and (2) audible lung crackles confirmed by physician. The nephrite samples were analyzed using polarized light and transmission electron microscopy combined with selected-area electron diffraction and energy-dispersive x-ray spectroscopy. After excluding 16 subjects with histories of tuberculosis or previous employment in metal casting and welding, as well as 23 family members who had not worked in the stone industry, we analyzed 305 subjects. Processing nephrite increased the risk for pulmonary fibrosis (odds ratio = 2.8 [95% confidence interval = 1.0-9.9] and unchanged after adjustment for age and smoking). Bulk sample analyses showed that the nephrite is a tremolite mineral composed of both asbestiform and non-asbestiform components. The cat's-eye nephrite had the highest asbestiform fibrous content, and the average length and aspect ratio of elongated mineral particles were the highest of all the nephrite types. Compared with workers processing other types of nephrite, workers processing cat's-eye nephrite had the highest risk for pulmonary fibrosis. Processing non-asbestiform tremolite mineral may increase the risk for pulmonary fibrosis. Medical monitoring is warranted for workers with such exposure.

CYP2E1 and XRCC1 Genetic Polymorphisms and the Risk of Liver Fibrosis in Workers Exposed to Vinyl Chloride Monomer

CYP2E1 and XRCC1 Genetic Polymorphisms and the Risk of Liver Fibrosis in Workers Exposed to Vinyl Chloride Monomer

Health hazards due to the inhalation of amorphous silica.

Occupational exposure to crystalline silica dust is associated with an increased risk for pulmonary diseases such as silicosis, tuberculosis, chronic bronchitis, chronic obstructive pulmonary disease (COPD) and lung cancer. This review summarizes the current knowledge about the health effects of amorphous (non-crystalline) forms of silica. The major problem in the assessment of health effects of amorphous silica is its contamination with crystalline silica. This applies particularly to well-documented pneumoconiosis among diatomaceous earth workers. Intentionally manufactured synthetic amorphous silicas are without contamination of crystalline silica. These synthetic forms may be classified as (1) wet process silica, (2) pyrogenic ("thermal" or "fumed") silica, and (3) chemically or physically modified silica. According to the different physicochemical properties, the major classes of synthetic amorphous silica are used in a variety of products, e.g. as fillers in the rubber industry, in tyre compounds, as free-flow and anti-caking agents in powder materials, and as liquid carriers, particularly in the manufacture of animal feed and agrochemicals; other uses are found in toothpaste additives, paints, silicon rubber, insulation material, liquid systems in coatings, adhesives, printing inks, plastisol car undercoats, and cosmetics. Animal inhalation studies with intentionally manufactured synthetic amorphous silica showed at least partially reversible inflammation, granuloma formation and emphysema, but no progressive fibrosis of the lungs. Epidemiological studies do not support the hypothesis that amorphous silicas have any relevant potential to induce fibrosis in workers with high occupational exposure to these substances, although one study disclosed four cases with silicosis among subjects exposed to apparently non-contaminated amorphous silica. Since the data have been limited, a risk of chronic bronchitis, COPD or emphysema cannot be excluded. There is no study that allows the classification of amorphous silica with regard to its carcinogenicity in humans. Further work is necessary in order to define the effects of amorphous silica on morbidity and mortality of workers with exposure to these substances.

Natural organic fibers--health effects.

Natural organic fibers are used in large quantities in the production of paper products and textiles. They are also constituents of food and added to food to promote health. The objective of this review is to evaluate the health effects of natural organic fibers. The health effects of dietary fibers are excluded from the review. This is a literature review. Exposure to these fibers in industry is usually not characterized as fibers but as dust. Rather dusty conditions have been reported in both paper and textile industries with concentrations up to and above 30 mg/m3. Both in the paper and textile industry inorganic fibers may occur making it hard to evaluate health effects of natural organic fibers from studies of workers in the paper and textile industry. There seems to be no increased risk of mesothelioma, lung cancer or lung fibrosis in workers exposed to natural organic fibers in contrast to workers exposed to inorganic crystalline fibers as asbestos. However, workers with a heavy exposure to paper dust or textile dust seem to have an increased risk of obstructive lung disease and bronchitis. These effects have not been causally linked to the fibrous shape of the particles but rather to the dust, chemicals absorbed on the dust or microorganisms occurring together with the dust. There is some indication that work in the textile industry may increase the risk of sinonasal cancer, but the etiological agents are unknown. Natural organic fibers are not causally linked with the well-known effects of some inorganic fibers, i.e. mesothelioma, lung cancer, lung fibrosis or some pleural diseases. The health effects of natural organic fibers, e.g. irritative effects, seem not to be linked to their fibrous shape.

The public health significance of the measurement of cytokines in serum

As variable functions of cytokines have been proved in recent years, cytokine levels in biological fluids such as serum, plasma, and synovial fluid of patients with every kind of disease have been enthusiastically measured. As a result, many studies have shown an increase or decrease in the production of cytokines or abnormal cytokine levels in biological fluids. However, the relationship between the abnormal levels of cytokines and the intensity of the clinical symptoms or the prognosis remains unclear. The significance for the measurement of cytokines depends on whether it should be valid for detecting a preclinical status such as AST or ALT used for health checks or for disease screening such as some tumor markers. The purpose of this study is to know whether or not some cytokine levels in serum could be biomarkers for preventive purposes. Serum cytokine levels (IL-4, 6, 8, 12, and IFN-gamma) were measured in three different types of cohorts (nursery school infants, manufacturing workers and middle and old aged women) with chemiluminescence ELISA. The results showed no differences with atopic status in infants, pulmonary fibrosis in workers or with the decrease in bone stiffness, these results are mainly due to a great inter-individual variability of serum cytokine levels. This study concludes that serum cytokine levels are inappropriate as biomarkers for preventive purposes. However, a further detailed evaluation in healthy people with high serum cytokine levels may be necessary.

Serum Type III Procollagen N-Terminal Peptide in Coal Miners

Health surveillance of workers exposed to fibrogenic agents ideally should identify individuals at risk or detect pulmonary fibrosis in preclinical stages. We investigated serum procollagen type III N-terminal peptide (PIIIP) in several groups of active miners and in a nondust-exposed control group. The purpose of this study was to determine the applicability of PIIIP as an early noninvasive marker of pulmonary fibrosis in workers exposed to coal mine dust. PIIIP levels were significantly elevated in miners without radiological signs of coal workers pneumoconiosis (CWP) as compared with the nonexposed controls. However, in coal miners with CWP beyond ILO classification 1/0, PIIIP levels were not significantly different from nondust-exposed controls. Trend analysis within the miners group indicated a decrease in PIIIP levels with progression of the fibrosis. Our data suggest that detection of early lung fibrosis by measuring serum PIIIP values may be more sensitive than radiological diagnosis of CWP. However, follow-up of the control miners with respect to serum PIIIP and chest radiography is essential to validate PIIIP as a biological marker for CWP.

Asbestos Bodies And Their Bioeffects

<h3>To the Editor:—</h3> This letter outlines the history of the asbestos body from its discovery through a period of little clinical significance to the present day when it holds the position of being possibly one of the greatest industrial medical problems of the age. <h3>Asbestos:—</h3> Asbestos is a general term that covers a number of minerals of which four are of commercial importance: crocidolite from the Republic of South Africa, amosite also mined chiefly in the Republic of South Africa, chrysolite which occurs in many countries of the world, and anthophyllite which is mined mainly in Europe. <h3>Asbestosis:—</h3> This is a type of lung fibrosis in workers exposed to large amounts of asbestos dust. It may or may not be associated with recognizable clinical disease during life and is produced by all types of asbestos. Asbestosis was recognized as an industrial disease at the turn of the century, but at

Pulmonary Disease Amongst Sisal Workers

The sisal industry is economically one of the most important in Kenya as it employs about 8,000 Africans who are engaged on work in 69 sisal plantations in the Colony. This corresponds to about 2 % of the total number of Africans employed in all public services, agricultural, and other indus tries. Employees on sisal estates are broadly speaking subject to the same diseases as other agricultural workers except that possibly tropical ulc?ration of the leg is more prevalent amongst them. The dusty conditions created by the brushing machines in the sisal factories, may, however, cause special hazards, as, apart from the general nuisance value of the dust, and its irritative action on the eyes and the upper respiratory tract, there remains the possibility that it might be responsible for damage to the lung tissue. The only reference in the literature which can be found which deals with the effect of sisal dust on the pulmonary tissues is that of an investigation carried out recently by Martins (1956) who clinically examined 118 operatives employed in the brushing rooms of three sisal estate factories in Mozambique. He reported that respiratory incapacity was more prevalent amongst brushing-room workers than others, and that he could find no flagrant signs of pneumoconiosis ; but it should be pointed out that he had no radiological facilities. Although this report by Martins is the only one available on sisal dust it is well known that other organic dusts of vegetable origin are capable of causing lung damage. Broadly speaking these dusts may affect the lungs in three different ways. First, they may produce allergic, asthmatic, and bronchitic conditions. A classical example is byssinosis, first described by Leach in 1863, and contracted by a considerable proportion of operatives working in the cardor blow-rooms in cotton mills. Asthmatic or bronchitic attacks may also occur amongst workers in the woollen industry (Moll, 1933), and amongst bakers (Anton, 1934; Ordman, 1947) and millers (Linko, 1947). Secondly, pulmonary disease may be caused by the inhalation of organic dust containing bacteria, fungi and moulds, and in particular, pulmonary mycosis may occur amongst persons exposed to moulded grain or hay (Fawcitt, 1936; T?rnell, 1946; Hoffmann, 1946). A variety of fungi may be the causative agents, but M. albicans, M. candida, and A. fumigatus appear to be the most frequent. Other fungi may also cause an allergic state giving rise to asthma and vasomotor rhinitis, and mites con taminating grain have been reported to give rise to pulmonary symptoms (Marcandier and Le Chuiton, 1928; Najera ?ngulo and Dantin Gallego, 1939). Caminita, Baum, Neal, and Schneiter (1947) have incriminated Aerobacter cloacae as being responsible for mill fever in cotton operatives. Schilling (1956) has described the same condition in workers preparing hemp and flax for spinning. A third possibility of pulmonary damage arising from exposure to vegetable dusts may be due, not to the effect of the dust itself, but to a high content of free silica mixed with it. Thus the pulmonary fibrosis in workers occupied in the stemming and redrying of tobacco from North Carolina is not due to the tobacco dust itself but to its admixture with free silica which occurs in high content in the soil in which the tobacco is grown (McCormick, Smith, and Marsh, 1948). Finally there is a group of pulmonary affections caused by organic dusts the aetiology of which are in doubt. One such disease is bagassosis which was first described by Jamison and Hopkins in 1941, and which results from exposure to the dust of the fibre trash remaining after the extraction of sugar from the sugar cane. Dunner, Hermon, and Bagnall (1946) have reported radiological findings of reticulation, mottling, and fibrosis amongst dockers handling grain and seeds, and they concluded that mycotic organisms were unlikely to have caused these changes.

Pulmonary disease amongst sisal workers.

The sisal industry is economically one of the most important in Kenya as it employs about 8,000 Africans who are engaged on work in 69 sisal plantations in the Colony. This corresponds to about 2 % of the total number of Africans employed in all public services, agricultural, and other indus tries. Employees on sisal estates are broadly speaking subject to the same diseases as other agricultural workers except that possibly tropical ulc?ration of the leg is more prevalent amongst them. The dusty conditions created by the brushing machines in the sisal factories, may, however, cause special hazards, as, apart from the general nuisance value of the dust, and its irritative action on the eyes and the upper respiratory tract, there remains the possibility that it might be responsible for damage to the lung tissue. The only reference in the literature which can be found which deals with the effect of sisal dust on the pulmonary tissues is that of an investigation carried out recently by Martins (1956) who clinically examined 118 operatives employed in the brushing rooms of three sisal estate factories in Mozambique. He reported that respiratory incapacity was more prevalent amongst brushing-room workers than others, and that he could find no flagrant signs of pneumoconiosis ; but it should be pointed out that he had no radiological facilities. Although this report by Martins is the only one available on sisal dust it is well known that other organic dusts of vegetable origin are capable of causing lung damage. Broadly speaking these dusts may affect the lungs in three different ways. First, they may produce allergic, asthmatic, and bronchitic conditions. A classical example is byssinosis, first described by Leach in 1863, and contracted by a considerable proportion of operatives working in the cardor blow-rooms in cotton mills. Asthmatic or bronchitic attacks may also occur amongst workers in the woollen industry (Moll, 1933), and amongst bakers (Anton, 1934; Ordman, 1947) and millers (Linko, 1947). Secondly, pulmonary disease may be caused by the inhalation of organic dust containing bacteria, fungi and moulds, and in particular, pulmonary mycosis may occur amongst persons exposed to moulded grain or hay (Fawcitt, 1936; T?rnell, 1946; Hoffmann, 1946). A variety of fungi may be the causative agents, but M. albicans, M. candida, and A. fumigatus appear to be the most frequent. Other fungi may also cause an allergic state giving rise to asthma and vasomotor rhinitis, and mites con taminating grain have been reported to give rise to pulmonary symptoms (Marcandier and Le Chuiton, 1928; Najera ?ngulo and Dantin Gallego, 1939). Caminita, Baum, Neal, and Schneiter (1947) have incriminated Aerobacter cloacae as being responsible for mill fever in cotton operatives. Schilling (1956) has described the same condition in workers preparing hemp and flax for spinning. A third possibility of pulmonary damage arising from exposure to vegetable dusts may be due, not to the effect of the dust itself, but to a high content of free silica mixed with it. Thus the pulmonary fibrosis in workers occupied in the stemming and redrying of tobacco from North Carolina is not due to the tobacco dust itself but to its admixture with free silica which occurs in high content in the soil in which the tobacco is grown (McCormick, Smith, and Marsh, 1948). Finally there is a group of pulmonary affections caused by organic dusts the aetiology of which are in doubt. One such disease is bagassosis which was first described by Jamison and Hopkins in 1941, and which results from exposure to the dust of the fibre trash remaining after the extraction of sugar from the sugar cane. Dunner, Hermon, and Bagnall (1946) have reported radiological findings of reticulation, mottling, and fibrosis amongst dockers handling grain and seeds, and they concluded that mycotic organisms were unlikely to have caused these changes.