Effect of Occupational Silica Exposure on Stone Crusher Workers

Abstract Background: Construction workers are at a high risk of exposure to various types of hazardous substances such as crystalline silica. Though multiple studies indicate the evidence regarding the effectiveness of different silica exposure reduction interventions in the construction sector, the decisions for selecting a specific silica exposure reduction intervention are best informed by an economic evaluation. Economic evaluation of interventions is subjected to uncertainties in practice, mostly due to the lack of precise data on important variables. In this study, we aim to identify the most cost-beneficial silica exposure reduction intervention for the construction sector under uncertain situation. Methods: We apply a probabilistic modeling approach that covers a large number of variables relevant to the cost of lung cancer, as well as the costs of silica exposure reduction interventions. To estimate the societal lifetime cost of lung cancer, we use an incidence cost approach. To estimate the net benefit of each intervention, we compare the expected cost of lung cancer cases averted, with expected cost of implementation of the intervention in one calendar year. Sensitivity analysis is used to quantify how different variables effects interventions net benefit.Results: A positive net benefit is expected for all considered interventions. The highest number of lung cancer cases are averted by combined use of wet method, local exhaust ventilation and personal protective equipment, about 107 cases, with expected net benefit of $45.9 million. Results also suggest that the level of exposure is an important determinant for the selection of the most cost-beneficial intervention.Conclusions: This study provides important insights for decision makers about silica exposure reduction interventions in the construction sector. It also provides an overview of the potential advantages of using probabilistic modeling approach to undertake economic evaluations, particularly when researchers are confronted with a large number of uncertain variables.

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Estimating Counterfactual Risk Under Hypothetical Interventions in the Presence of Competing Events: Crystalline Silica Exposure and Mortality From 2 Causes of Death

American Journal of Epidemiology ◽

10.1093/aje/kwy077 ◽

2018 ◽

Vol 187 (9) ◽

pp. 1942-1950 ◽

Cited By ~ 2

Author(s):

Andreas M Neophytou ◽

Sally Picciotto ◽

Daniel M Brown ◽

Lisa E Gallagher ◽

Harvey Checkoway ◽

...

Keyword(s):

Causes Of Death ◽

Crystalline Silica ◽

Silica Exposure ◽

Competing Events

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Dusty trades and associated rheumatoid arthritis in a population-based study in the coal mining counties of Appalachia

Occupational and Environmental Medicine ◽

10.1136/oemed-2021-107899 ◽

2022 ◽

pp. oemed-2021-107899

Author(s):

Gabriela Schmajuk ◽

Laura Trupin ◽

Edward H Yelin ◽

Paul D Blanc

Keyword(s):

Rheumatoid Arthritis ◽

Coal Mining ◽

Smoking Status ◽

Strong Association ◽

Population Based ◽

Cross Sectional ◽

Silica Exposure ◽

Random Digit Dial ◽

Ergonomic Exposure ◽

Ergonomic Exposures

ObjectivesWe previously showed increased coal mining-associated risk of rheumatoid arthritis (RA). Using additional survey data, we sought to delineate this risk further.MethodsWe used data from two cross-sectional, random-digit-dial, population-based surveys (males;≥50 years) in selected counties in the Appalachian region of the inland, mid-Atlantic USA with elevated pneumoconiosis mortality. Surveys ascertained age, smoking, coal mining and non-coal silica exposure jobs. In a subset, we surveyed ergonomic exposures, scored by intensity. We queried diagnosis of RA, corticosteroid use, and, in a subset, use of disease modifying antirheumatic drugs (DMARDs). Multivariable logistic regression modelled RA risk (defined by glucocorticoid or DMARDs use) associated with coal mining employment, other silica exposure, smoking status, and age and ergonomic exposures.ResultsWe analysed data for 2981 survey respondents (mean age 66.6 years; 15% current, 44% ex-smokers). The prevalence of glucocorticoid-treated and DMARD-treated RA was 11% and 4%, respectively. Glucocorticoid-treated RA was associated with coal mining (OR 3.5; 95% CI 2.5 to 4.9) and non-coal mining silica exposure (OR 3.2; 95% CI 2.4 to 4.4). For DMARD-treated RA, the odds associated with coal mining and other silica remained elevated: OR 2.3 (95% CI 1.18, 4.5) and OR 2.7 (95% CI 1.51, 5.0), respectively. In the same model, the highest intensity ergonomic exposure also was associated with increased odds of RA (OR 4.3; 95% CI 1.96 to 9.6).ConclusionsWe observed a strong association between coal mining and other silica-exposing dusty trades and RA. Clinicians and insurers should consider occupational histories in the aetiology of RA.

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miR-135a Alleviates Silica-Induced Pulmonary Fibrosis by Targeting NF-κB/Inflammatory Signaling Pathway

Mediators of Inflammation ◽

10.1155/2020/1231243 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Bin Xie ◽

Can Lu ◽

Chen Chen ◽

Jianhua Zhou ◽

Zhenghao Deng

Keyword(s):

Cell Proliferation ◽

Pulmonary Fibrosis ◽

Inflammatory Response ◽

Inflammatory Mediators ◽

Protein Level ◽

Molecular Mechanisms ◽

Cancer Cell Proliferation ◽

Inflammatory Signaling ◽

Silica Exposure ◽

Collective Data

Silica exposure triggers inflammatory response and pulmonary fibrosis that is a severe occupational or environmental lung disease with no effective therapies. The complicated biological and molecular mechanisms underlying silica-induced lung damages have not yet been fully understood. miR-135a inhibits inflammation, apoptosis, and cancer cell proliferation. But the roles of miRNA135a involved in the silica-induced lung damages remain largely unexplored. We investigated the roles and mechanisms of miR-135a underlying silica-induced pulmonary fibrosis. The present study showed silica exposure caused the decrease in miR-135a level but the increase in inflammatory mediators. Transduction of lentivirus expressing miR-135a reduced the level of inflammatory mediators in lung tissues from silica-treated mice and improved pulmonary fibrosis which was consistent with the downregulated α-SMA but enhanced E-cadherin. Moreover, miR-135a overexpression inhibited p-p65 level in lung tissues. Overexpression of miR-135a inhibitor strengthened TLR4 protein level and NF-κB activation in BEAS-2B cells. Injection of PDTC, an inhibitor of NF-κB, further reinforced miR-135a-mediated amelioration of inflammation and pulmonary fibrosis induced by silica. The collective data indicate miR-135a restrains NF-κB activation probably through targeting TLR4 to alleviate silica-induced inflammatory response and pulmonary fibrosis.

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Microscopic polyangiitis in a case of silica exposure: a rare presentation

Monaldi Archives for Chest Disease ◽

10.4081/monaldi.2019.1087 ◽

2019 ◽

Vol 89 (3) ◽

Author(s):

Nitesh Gupta ◽

A J Mahendran ◽

Shibdas Chakrabarti ◽

Sumita Agrawal

Keyword(s):

Microscopic Polyangiitis ◽

Antineutrophil Cytoplasmic Antibody ◽

Final Diagnosis ◽

Alveolar Haemorrhage ◽

Diffuse Alveolar Haemorrhage ◽

Hypoxemic Respiratory Failure ◽

Rare Presentation ◽

Arterial Blood Gas ◽

Silica Exposure ◽

Arterial Blood

A 28-year-old male was admitted for breathlessness, haemoptysis, fever and fatigue. The patient had occupational exposure to silica dust. Arterial blood gas test ABG revealed hypoxemic respiratory failure. Chest CT demonstrated ground glass opacities with interlobular septal thickening and small centrilobular nodules with patchy areas of consolidation in bilateral lungs. He was mechanically ventilated for refractory hypoxemia. The treatment with cyclophosphamide and methylprednisolone lead to recovery and extubation. The final diagnosis was diffuse alveolar haemorrhage due to perinuclear antineutrophil cytoplasmic antibody (ANCA)-associated microscopic polyangiitis (p-ANCA-associated MPA). In a tuberculosis endemic country, for patients presenting with diffuse alveolar haemorrhage (DAH), with history of silica exposure, differential diagnosis of ANCA associated vasculitis must be considered.

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