Progression of coal workers' pneumoconiosis absent further exposure.

OBJECTIVES: The natural history of coal workers' pneumoconiosis (CWP) after cessation of exposure remains poorly understood. METHODS: We characterised the development of and progression to radiographic progressive massive fibrosis (PMF) among former US coal miners who applied for US federal benefits at least two times between 1 January 2000 and 31 December 2013. International Labour Office classifications of chest radiographs (CXRs) were used to determine initial and subsequent disease severity. Multivariable logistic regression models were used to identify major predictors of disease progression. RESULTS: A total of 3351 former miners applying for benefits without evidence of PMF at the time of their initial evaluation had subsequent CXRs. On average, these miners were 59.7 years of age and had 22 years of coal mine employment. At the time of their first CXR, 46.7% of miners had evidence of simple CWP. At the time of their last CXR, 111 miners (3.3%) had radiographic evidence of PMF. Nearly half of all miners who progressed to PMF did so in 5 years or less. Main predictors of progression included younger age and severity of simple CWP at the time of initial CXR. CONCLUSIONS: This study provides further evidence that radiographic CWP may develop and/or progress absent further exposure, even among miners with no evidence of radiographic pneumoconiosis after leaving the industry. Former miners should undergo regular medical surveillance because of the risk for disease progression.

Dust induces lung fibrosis through dysregulated DNA methylation.

Pneumoconiosis is a serious occupational disease that often occurs to coal workers with no early diagnosis and effective treatment at present. Diffuse pulmonary fibrosis is the major pathological change of pneumoconiosis, and its mechanism is still unclear. Epigenetics is involved in the development of many diseases, and it is closely associated with fibrosis. In this study, we investigated whether DNA methylation contributes to the pathogenesis of pulmonary fibrosis in pneumoconiosis. By exposure to coal dust or silica dust, we established the models of coal worker's pneumoconiosis (CWP), which showed an increased expression of COL-I, COL-III. We further found that DNMT1, DNMT3a, DNMT3b, MBD2, MeCP2 protein expression changed. Pretreatment with DNMT inhibitor 5-aza-dC reduced expression of COL-I, COL-III, and reduced pulmonary fibrosis. In summary, our results showed that DNA methylation contributes to dust-induced pulmonary fibrosis and that it may serve as a theoretical basis for testing DNA methyltransferase inhibitors in the treatment of CWP.

Progressive Massive Fibrosis Identified at Federally Funded Black Lung Clinics in the US.

This study of US Black Lung Clinics (established to treat coal miners) reports the prevalence of progressive massive fibrosis identified through June 2023.

Coal mine dust lung disease in the modern era.

Coal workers' pneumoconiosis (CWP), as part of the spectrum of coal mine dust lung disease (CMDLD), is a preventable but incurable lung disease that can be complicated by respiratory failure and death. Recent increases in coal production from the financial incentive of economic growth lead to higher respirable coal and quartz dust levels, often associated with mechanization of longwall coal mining. In Australia, the observed increase in the number of new CWP diagnoses since the year 2000 has necessitated a review of recommended respirable dust exposure limits, where exposure limits and monitoring protocols should ideally be standardized. Evidence that considers the regulation of engineering dust controls in the mines is lacking even in high-income countries, despite this being the primary preventative measure. Also, it is a global public health priority for at-risk miners to be systemically screened to detect early changes of CWP and to include confirmed patients within a central registry; a task limited by financial constraints in less developed countries. Characteristic X-ray changes are usually categorized using the International Labour Office classification, although future evaluation by low-dose HRCT) chest scanning may allow for CWP detection and thus avoidance of further exposure, at an earlier stage. Preclinical animal and human organoid-based models are required to explore potential re-purposing of anti-fibrotic and related agents with potential efficacy. Epidemiological patterns and the assessment of molecular and genetic biomarkers may further enhance our capacity to identify susceptible individuals to the inhalation of coal dust in the modern era.

Flexible link functions in nonparametric binary regression with Gaussian process priors.

In many scientific fields, it is a common practice to collect a sequence of 0-1 binary responses from a subject across time, space, or a collection of covariates. Researchers are interested in finding out how the expected binary outcome is related to covariates, and aim at better prediction in the future 0-1 outcomes. Gaussian processes have been widely used to model nonlinear systems; in particular to model the latent structure in a binary regression model allowing nonlinear functional relationship between covariates and the expectation of binary outcomes. A critical issue in modeling binary response data is the appropriate choice of link functions. Commonly adopted link functions such as probit or logit links have fixed skewness and lack the flexibility to allow the data to determine the degree of the skewness. To address this limitation, we propose a flexible binary regression model which combines a generalized extreme value link function with a Gaussian process prior on the latent structure. Bayesian computation is employed in model estimation. Posterior consistency of the resulting posterior distribution is demonstrated. The flexibility and gains of the proposed model are illustrated through detailed simulation studies and two real data examples. Empirical results show that the proposed model outperforms a set of alternative models, which only have either a Gaussian process prior on the latent regression function or a Dirichlet prior on the link function.

Black Lung Benefits Act: standards for chest radiographs. Final rule.

Physicians and adjudicators use chest radiographs (X-rays) as a tool in evaluating whether a coal miner suffers from pneumoconiosis (black lung disease). Accordingly, the Department's regulations implementing the Black Lung Benefits Act allow the submission of radiographs in connection with benefit claims and set out quality standards for administering and interpreting film-based chest radiographs. This final rule updates the Department's existing film-radiograph standards and provides parallel standards for digital radiographs. This rule also updates outdated terminology and removes certain obsolete provisions.

Lung transplantation in patients with coal workers' pneumoconiosis.

Patients with coal workers' pneumoconiosis (CWP) can develop chronic respiratory failure and require lung transplantation. A retrospective review was performed of the 712 referrals and 143 patients undergoing unilateral or bilateral lung transplantation at the University of Kentucky Medical Center between January 1999 and July 2009. Twenty-one of the 712 referrals (3%) had a diagnosis of CWP with eight patients eventually undergoing lung transplant (six single, two bilateral). The mean age of the cohort was 53 ± 5 (mean ± SD) yr (range 45-59). There was no increased risk of perioperative or postoperative complications. Six patients (75%) remain alive after a mean follow-up of 1013 ± 857 d with the two deaths attributable to sepsis 683 and 145 d after transplant, respectively. There were no pulmonary complications because of the native lung in patients after a single lung transplant, with otherwise good clinical outcomes seen after lung transplantation.

Pyrite-driven reactive oxygen species formation in simulated lung fluid: implications for coal workers' pneumoconiosis.

The origin of coal worker's pneumoconiosis (CWP) has been long debated. A recent epidemiological study shows a correlation between what is essentially the concentration of pyrite within coal and the prevalence of CWP in miners. Hydrogen peroxide and hydroxyl radical, both reactive oxygen species (ROS), form as byproducts of pyrite oxidative dissolution in air-saturated water. Motivated by the possible importance of ROS in the pathogenesis of CWP, we conducted an experimental study to evaluate if ROS form as byproducts in the oxidative dissolution of pyrite in simulated lung fluid (SLF) under biologically applicable conditions and to determine the persistence of pyrite in SLF. While the rate of pyrite oxidative dissolution in SLF is suppressed by 51% when compared to that in air-saturated water, the initial amount of hydrogen peroxide formed as a byproduct in SLF is nearly doubled. Hydroxyl radical is also formed in the experiments with SLF, but at lower concentrations than in the experiments with water. The formation of these ROS indicates that the reaction mechanism for pyrite oxidative dissolution in SLF is no different from that in water. The elevated hydrogen peroxide concentration in SLF suggests that the decomposition, via the Fenton mechanism to hydroxyl radical or with Fe(III) to form water and molecular oxygen, is initially inhibited by the presence of SLF components. On the basis of the oxidative dissolution rate of pyrite measured in this paper, it is calculated that a respirable two micron pyrite particle will take over 3 years to dissolve completely.

A pilot study on the lung morphology of shelter dogs in relation to air pollution in Trinidad.

OBJECTIVE: To identify and characterize the gross and histological lesions associated with air pollution in the lungs of dogs from various locations in Trinidad. ANIMALS: 56 fresh lungs were obtained from already euthanized adult dogs collected from different locations in Trinidad at the Trinidad and Tobago Society for the Prevention of Cruelty to Animals. PROCEDURES: Lung specimens were examined grossly and tissue samples were taken for routine histologic examination. RESULTS: Histological examination showed that 51.8% of the dogs had evidence of anthracosis. Dogs with anthracosis had greater median lesion scores compared to dogs without anthracosis (P = .022). There was no association between the presence of anthracosis and any other lesion in this study (P > .05). CLINICAL RELEVANCE: There was evidence that dogs with anthracosis had a greater degree of nonspecific lung histologic lesions. Using the dog as a sentinel model for human exposure in Trinidad, our findings indicate that environmental air pollution may also have an effect on the respiratory health of the human population. It is important for the public to be aware of air pollution, and the government of Trinidad and Tobago should develop an intervention protocol along with veterinary and human medical epidemiologists to reduce air pollution in the country.

A systematic review and meta-analysis on international studies of prevalence, mortality and survival due to coal mine dust lung disease.

BACKGROUND: Coal mine dust lung disease comprises a group of occupational lung diseases including coal workers pneumoconiosis. In many countries, there is a lack of robust prevalence estimates for these diseases. Our objective was to perform a systematic review and meta-analysis of published contemporary estimates on prevalence, mortality, and survival for coal mine dust lung disease worldwide. METHODS: Systematic searches of PubMed, EMBASE and Web of Science databases for English language peer-reviewed articles published from 1/1/2000 to 30/03/2021 that presented quantitative estimates of prevalence, mortality, or survival for coal mine dust lung disease. Review was conducted per PRISMA guidelines. Articles were screened independently by two authors. Studies were critically assessed using Joanna Briggs Institute tools. Pooled prevalence estimates were obtained using random effects meta-analysis models. Heterogeneity was measured using the I2 statistics and publication bias using Egger's tests. RESULTS: Overall 40 studies were included, (31 prevalence, 8 mortality, 1 survival). Of the prevalence estimates, fifteen (12 from the United States) were retained for the meta-analysis. The overall pooled prevalence estimate for coal workers pneumoconiosis among underground miners was 3.7% (95% CI 3.0-4.5%) with high heterogeneity between studies. The pooled estimate of coal workers pneumoconiosis prevalence in the United States was higher in the 2000s than in the 1990s, consistent with published reports of increasing prevalence following decades of declining trends. Sub-group analyses also indicated higher prevalence among underground miners, and in Central Appalachia. The mortality studies were suggestive of reduced pneumoconiosis mortality rates over time, relative to the general population. CONCLUSION: The ongoing prevalence of occupational lung diseases among contemporary coal miners highlights the importance of respiratory surveillance and preventive efforts through effective dust control measures. Limited prevalence studies from countries other than the United States limits our understanding of the current disease burden in other coal-producing countries.

Anthracosis and large mediastinal mass in a patient with healed pulmonary tuberculosis.

A Mexican woman, aged 71 years, with life-long exposure to soot from a wood cook stove in a closed environment, who was treated for tuberculosis 4-years prior, presented with prominent mediastinal lymphadenopathy with anthracosis. Mediastinal lymphadenopathy is a common presentation of diverse granulomatous, malignant and infectious conditions like tuberculosis. Anthracotic pigment is found in different conditions such as tuberculosis or domestically acquired particulate lung disease. Accurate assessment of chronology and causative factors presents a challenge. Recognizing that pneumoconiosis can mimic or coexist with other granulomatous, infectious and malignant conditions presenting as mediastinal lymphadenopathy is important. Misdiagnosis may result in under- or over-treatment of potentially curable conditions such as tuberculosis, under-treatment of a lethal condition such as melanoma, or exposure of patients to inappropriate administration of costly therapy with potential untoward effects.

Working conditions and pneumoconiosis in Turkish coal miners between 1985 and 2004: a report from Zonguldak coal basin, Turkey.

In Turkey, bituminous coal mining is performed only in Zonguldak coal basin since 1940. Pneumoconiosis surveillance programs and dust control measures are in effect, but published pneumoconiosis data from this area is lacking. In this study, we aimed to evaluate the change in prevalence and case detection between 1985 and 2004 and assess the correlation between the dust concentration in workplaces and the prevalence of pneumoconiosis. Data on respirable dust concentrations and number of workers diagnosed as pneumoconiosis between 1985 and 2004 were obtained from Turkish Coal Enterprises authorities. Mean respirable dust concentrations in workplaces underground and on the ground were 1.66 mg/m(3) and 0.73 mg/m(3) respectively. Total number of workers decreased from 38.231 in 1985 to 12.261 in 2004 including 8932 underground workers. In this period, pneumoconiosis has not been reported in the ground workers. Incidence of pneumoconiosis ranged between 0.17-2.8 percent and prevalence ranged between 1.23-6.23 percent between 1985 and 2004. Radiologic opacities compatible with pneumoconiosis were predominantly small opacities. This is the first report about the incidence and prevalence rate of coal worker's pneumoconiosis in the main coal mining area of Turkey. Dust measurement and screening standards should be improved and adapted to international standards and we conclude that surveillance data should be closely monitored in this region and further epidemiologic studies in this area are warranted.

Prediction of the length of service at the onset of coal workers' pneumoconiosis based on neural network.

Three environmental parameters, i.e. dust concentrations, dust dispersion, and free silica content, were introduced into the traditional indices of the neural network model in order to construct a new prediction index and explore a new method for preventing the incidence of pneumoconiosis with intelligent accuracy and universality. Data of the pneumoconiosis patients from Huabei Mining Group (HBMG) of China from 1980 to 2017 were collected. SPSS22.0 was used to develop the combined models based on Back Propagation (BP) neural network model, Radial Basis Function (RBF) neural network model, and Multiple Linear Regression (MLR) model. The paired sample t-test was performed between the real and predicted values. According to this model, it was predicted that 382 coal workers in HBMG were likely to suffer from pneumoconiosis in 2022 and the incidence rate was 4.48%. It is necessary to take prevention measures and transfer these workers from their current positions. In four combined models, the BP-MLR combined model achieved the optimal error parameters and the most accurate prediction. This study provided a scientific basis for effective control and prevention of the incidence of the pneumoconiosis.

Bronchial anthracostenosis with mediastinal fibrosis associated with long-term wood-smoke exposure.

Bronchial anthracostenosis describes a disease entity consisting of bronchial destruction, deformity and stenosis related to dark pigmentation on bronchoscopy in patients with a history of coal workers' pneumoconiosis or chronic exposure to biomass smoke. The combined occurrence of bronchial anthracostenosis and mediastinal fibrosis in association with wood-smoke exposure has not been previously reported. This case report describes a non-cigarette smoking elderly woman who developed bronchial anthracostenosis and mediastinal fibrosis after long-term exposure to wood smoke. Clinical and radiological improvements were achieved after treatment with corticosteroid and tamoxifen. Awareness of this unusual entity will help to avoid misdiagnosis of malignancy or unnecessary thoracotomy.

Distract, delay, disrupt: examples of manufactured doubt from five industries.

Manufactured doubt describes the efforts used by organizations or individuals to obscure the harmful effects of their products or actions by manipulating science. Although approaches to do so are widely used, relevant stakeholders are often unaware of these tactics. Here, we examine the strategies used in five cases of manufactured doubt: tobacco and adverse health; coal and black lung; Syngenta and the herbicide atrazine; the sugar industry and cardiovascular disease; and the Marshall Institute and climate change. By describing the tactics used in these cases, effective methods for identifying and countering instances of manufactured doubt can be generated.

Black lungs in the general population: a new look at an old dispute.

Almost from the time that autopsies were first routinely carried out, darkening of lungs with increasing age was described. Different explanations for the origin of the accumulating black pigment arose and by the early nineteenth century three hypotheses had emerged: 1) soot inhaled into the lungs from the air; 2) carbon accumulating in the lungs from abnormal pulmonary carbon dioxide metabolism; and, 3) pigment derived from the blood. In 1813 the English physician and chemist George Pearson published a paper in which he described the recovery of the black pigment from lungs and its chemical analysis. Pearson declared the black pigment to be airborne carbon/soot from the burning of coal and wood. He described these particles depositing in 'black spots' in the terminal airways and accumulating in the peribronchial lymph nodes, forming 'black glands'. Despite Pearson's prescient account, debate continued and the true explanation, given in that paper, was not fully accepted until the late nineteenth century.

James Craufurd Gregory, 19th century Scottish physicians, and the link between occupation as a coal miner and lung disease.

By the mid-19th century about 200,000 miners were employed in a UK coal mining industry still growing with the advances of the Industrial Revolution. Coal miners were long known to suffer poor health but the link to inhaling dust in the mines had not been made. In 1813 George Pearson was the first to suggest that darkening of lungs seen in normal individuals as they aged was caused by inhaled soot from burning oil, candles and coal, which were the common domestic sources of heat and light. In 1831 Dr James Craufurd Gregory first described black pigmentation and disease in the lungs of a deceased coal miner and linked this to pulmonary accumulation of coal mine dust. Gregory hypothesised that the black material seen at autopsy in the collier's lungs was inhaled coal dust and this was confirmed by chemical analysis carried out by Professor Sir Robert Christison. Gregory suggested that coal dust was the cause of the disease and warned physicians in mining areas to be vigilant for the disease. This first description of what came to be known as 'coal worker's pneumoconiosis' sparked a remarkable intellectual effort by physicians in Scotland, culminating in a large body of published work that led to the first understandings of this disease and its link to coalblackened lungs. This paper sets out the history of the role of Scottish physicians in gaining this understanding of coal worker's pneumoconiosis. It describes Gregory's case and the lung - recently discovered in the pathology collection of the Surgeons' Hall Museums, Edinburgh, where it has lain unnoticed for over 180 years - on which Gregory based his landmark paper.

The concomitant occurrence of pulmonary tuberculosis with bronchial anthracofibrosis.

BACKGROUND: Bronchial anthracofibrosis (BAF), diagnosed bronchoscopically, is a clinical entity which is now beginning to emerge from obscurity. This is commonly encountered in elderly females with history of long-standing exposure to biomass fuel smoke in poorly ventilated kitchens. As awareness of BAF has increased in recent times, distinct clinicoradiological and bronchoscopic features of the disease have emerged. Diagnosis is achieved by visualisation of bluish-black mucosal hyperpigmentation along with narrowing/distortion of the affected bronchus on fibreoptic bronchoscopy (FOB). BAF was first recognised nearly a decade ago in India, when a 65-year-old female who presented with a middle lobe syndrome (MLS) was diagnosed with concomitant pulmonary tuberculosis and BAF. Pulmonary tuberculosis, seen in up to one-third of patients with BAF, is now considered to be an associated condition rather than a causative agent, as was initially postulated. METHODS: Respiratory symptomatics with a history of biomass fuel smoke exposure underwent high-resolution computed tomography (HRCT) of chest as well as FOB to establish a diagnosis of BAF. In patients who were diagnosed with BAF, an association with tuberculosis was also sought for. RESULTS: Of the 31 patients diagnosed with BAF in one unit, four had an associated diagnosis of tuberculosis. Cough was the most common presenting symptom seen in all four patients. Imaging revealed consolidation in 3/4 subjects, nodular lesions in one and in another one multifocal narrowing on HRCT, a feature characteristic of BAF. One patient had a diagnosis of MLS. FOB, in all four subjects, visualised anthracotic pigmentation along with narrowing/distortion of the affected bronchi with the left upper lobe bronchus being most commonly affected. Stains and cultures of the bronchial aspirate for Mycobacterium tuberculosis were positive in all four patients while GeneXpert performed in three was positive in all. Rifampicin resistance was not detected. One patient had an actively caseating form of endobronchial tuberculosis as evidenced by oedematous, hyperemic mucosa along with whitish cheese-like material affecting the right middle lobe as was seen on FOB. CONCLUSION: Once a diagnosis of tuberculosis is established in a patient with long-standing exposure to biomass fuel smoke, invasive procedure required for the diagnosis of BAF is usually not considered and the diagnosis would remain confined to pulmonary tuberculosis. This study highlights the need to recognise BAF and to exclude pulmonary tuberculosis in such patients.

[Black smoke lung disease ­ a new disease in Sweden]. / Sotrökslunga är en ny sjukdom i Sverige - Exponering för rök från biomassa är orsaken.

Black smoke lung disease - a new disease in Sweden We describe two elderly female patients, immigrants to Sweden from Afghanistan, with intensive longtime exposure to smoke from biomass, and who presented with bronchial stenosis and severe bronchial obstruction. CT and X-ray showed bizarre perihilar infiltrates in the lungs. Bronchoscopy revealed black narrow bronchi with a middle lobe stenosis in one of the patients. These findings indicate the diagnosis bronchial anthracofibrosis (BAF). The here described findings are seen mainly in elderly never-smoking women from developing countries who have spent years cooking food in poorly ventilated kitchens. With increased immigration from these countries such cases will be seen in industrialized countries as well. Active tuberculosis must always be excluded but otherwise no more active investigations such as biopsies are warranted. We suggest that this disease should be termed ¼black smoke disease« to differentiate it from coal workers' pneumoconiosis, silicosis, and other classical occupational diseases which can have similar clinical and radiological pictures. This term is easily understood even by non-medical persons and illustratess both the etiology and the black bronchi.