Prevalence Of Coal Workers' Pneumoconiosis Research Articles

Respiratory health of American Indian and Alaska Native coal miners participating in the Coal Workers' Health Surveillance Program, 2014-2019.

In 2014, a federal rule reduced occupational exposure limits to coal mine dust and expanded medical surveillance eligibility beyond underground miners to surface and contract coal miners. This expansion may have provided an opportunity for more American Indian and Alaska Native (AI/AN) coal miners to participate in screening, since many surface coal mines are located near AI/AN communities and may employ AI/AN miners. Therefore we sought to better understand the respiratory health of AI/AN coal miners by characterizing prevalence of coal workers' pneumoconiosis (CWP), progressive massive fibrosis (PMF), and abnormal lung function in this population. Descriptive analysis of 1405 chest radiographs and 627 spirometry test results for AI/AN miners who participated in the Coal Workers' Health Surveillance Program (CWHSP) during 2014-2019 was conducted. Most AI/AN miners (0-25+ years of tenure) were western United States residents (82.3%) and active surface miners (76.9%) with no underground tenure. Among miners with at least 10 years of tenure, prevalence of CWP was 3.0%, and of PMF was 0.3%. Lung function abnormalities were seen in 9.0% with primarily restrictive patterns. The prevalence of CWP, PMF, and lung function abnormality among active and former AI/AN coal miners was higher than seen in a larger CWHSP study of active western miners working primarily underground with 10+ years of tenure. Interventions that eliminate or control coal mine dust exposure, identify miners with CWP early, and limit respiratory disease progression and complications remain vital for eliminating the preventable adverse health effects of coal mining. Comprehensive demographic data on the coal mining workforce are needed to improve CWHSP participation assessment.

Coal Workers' Pneumoconiosis at PT. A Sawahlunto and The Influencing Factors

Background: Coal workers’s pneumoconiosis (black lung disease) is an interstitial lung disease caused by chronic inhalation of coal dust. The incidence of coal workers’s pneumoconiosis increased globally from the 1990s to the 2000s by 3.2%. Indonesia is the country which has many coal mining, but national prevalence of coal workers pneumoconiosis was not discovered. PT. A is one of mining companies in Sawahlunto. The aims of this study was to determine the incidence of coal workers’ pneumoconiosis at PT. A Sawahlunto and it’s influencing factors. Methods: This study is an analytic study with cross sectional design, conducted from November 2019 to April 2020. There were 90 coal miners participated in this study. All subjects were performed chest X-ray examination with ILO standard to asses the incidence of pneumoconiosis. Spirometr examination, dust level measurement with portable low volume air sampler, interview, and validated questionnare were performed to evaluate it’s influencing factors. Statistical analysis used Chi-square test and double logistic regression test. Results: This study found 12 workers (13.3%) had pneumoconiosis. From the statistical test results obtained age >50 years (P=0.035), duration of exposure (P=0.040), mask usage (P=0.029), restrictive lung function (P=0.004), and the mixed abnormality lung function (P=0.006) is associated with pneumoconiosis. The most dominant factor was mask usage (P=0.049) with OR=5.026 Conclusion: The most dominant factor that influence coal workers’ pneumoconiosis was mask usage. Others related factors were age, duration of exposure and abnormality lung function.

Estimating the prevalence and spatial clusters of coal workers' pneumoconiosis cases using medicare claims data, 2011-2014.

Workers employed in the coal mining sector are at increased risk of respiratory diseases, including coal workers' pneumoconiosis (CWP). We investigated the prevalence of CWP and its association with sociodemographic factors among Medicare beneficiaries. We used 5% Medicare Limited Data Set claims data from 2011 to 2014 to select Medicare beneficiaries with a diagnosis of ICD-9-CM 500 (CWP). We aggregated the data by county and limited our analysis to seven contiguous states: Illinois, Indiana, Kentucky, Ohio, Pennsylvania, Virginia, and West Virginia. We estimated county-level prevalence rates using total Medicare beneficiaries and miners as denominators and performed spatial hotspot analysis. We used negative binomial regression analysis to determine the association of county-wise sociodemographic factors with CWP. There was significant spatial clustering of CWP cases in Kentucky, Virginia, and West Virginia. Spatial clusters of 210 and 605 CWP cases representing an estimated 4200 to 12 100 cases of Medicare beneficiaries with CWP were identified in the three states. Counties with higher poverty levels had a significantly elevated rate of CWP (adjusted rate ratios [RR]: 1.15; 95% CI, 1.12-1.18). There was a small but significant association of CWP with the county-wise catchment area. Rurality was associated with a more than three-fold elevated rate of CWP in the unadjusted analysis (RR: 3.28, 95% CI, 2.22-4.84). However, the rate declined to 1.45 (95% CI, 1.04-2.01) after adjusting for other factors in the analysis. We found evidence of significant spatial clustering of CWP among Medicare beneficiaries living in the seven states of the USA.

Coal mining and lung disease in the 21st century.

To review the impact of coal mining and resurgence of coal workers' pneumoconiosis (CWP) in 21st century and effect of ambient air pollution on lung function. At the beginning of 21st century, statistics by National Institute for Occupational Safety and Health showed a steep rise in pneumoconiosis. This was followed by numerous epidemiologic and pathologic studies that confirmed increasing CWP prevalence as well as disease in younger miners and those with a shorter mining tenure. Recent studies have demonstrated that poor dust control in mines, a relative shift in composition of the coal mine dust, small sized mines and increase in surface mining are all possible contributors to this resurgence. There is also growing literature evaluating the effects of worsening air pollution on health, including decreasing lung function and development of emphysema, worsening quality of life measures and lung cancer. This irreversible but preventable disease currently haunts approximately 60 000 miners across United States and millions across the world. Its resurgence despite the strict dust regulations is a setback from the public health standpoint. The continued reliance on coal for energy will continue to place coal miners at danger of developing disease as well as the world.

Combined effect of coal dust exposure and smoking on the prevalence of respiratory impairment among coal miners of West Bengal, India

Accelerating prevalence of coal workers pneumoconiosis is considered as a serious occupational health problem. This cross-sectional study was designed to determine the prevalence of lung function impairment of underground coal miners in West Bengal, India. A total of 230 underground coal dust-exposed subjects and 130 nonexposed subjects were examined for lung function test and also information on sociodemographic characteristics, addiction, respiratory morbidity, personnel protective equipment and dust exposure were collected. Lung function impairment was significantly higher in exposed group than nonexposed group and personnel dust exposure level were exceeded above the NIOSH recommended level. In addition, respiratory ailments were found to be higher in exposed group than the nonexposed group. So, this study has established the need for an advanced understanding of the quantifiable and measurable remedies for protection of lung disorder of coal mine workers.

Continued Increase in Prevalence of Coal Workers' Pneumoconiosis in the United States, 1970-2017.

To update prevalence estimates for coal workers' pneumoconiosis (CWP) among working underground coal miners in the United States. We conducted a prevalence study using radiographs collected from 1970 to 2017. We classified each radiograph using international standards. We defined CWP as the presence of small opacities, with profusion greater than or equal to subcategory 1/0, or the presence of a large opacity larger than 1 centimeter. Following a low point in the late 1990s, the national prevalence of CWP in miners with 25 years or more of tenure now exceeds 10%. In central Appalachia (Kentucky, Virginia, West Virginia), 20.6% of long-tenured miners have CWP. When we excluded miners from central Appalachia, the prevalence for the remainder of the United States was lower, but an increase since 2000 remains evident. The national prevalence of CWP among working coal miners is increasing. This increase is most pronounced in central Appalachia. Current CWP prevalence estimates will likely be reflected in future trends for severe and disabling disease, including progressive massive fibrosis. Public Health Implications. Recently enacted protections to prevent coal mine dust exposure and identify CWP at its early stage remain essential to protect US coal miners.

Continued increase in lung transplantation for coal workers' pneumoconiosis in the United States.

Severe coal workers' pneumoconiosis (CWP) is increasingly common, and sometimes requires lung transplantation. Using Organ Procurement and Transplantation Network data, we updated the trend for CWP-related lung transplants, described CWP patients who have been waitlisted but not transplanted, and characterized the primary payer of medical costs for CWP-related and other occupational lung disease transplants. There have been at least 62 CWP-related lung transplants; 49 (79%) occurred in the last decade. The rate of these procedures has also increased. Twenty-seven patients were waitlisted but did not receive a transplant. Compared to other occupational lung diseases, transplants for CWP were more likely to be paid for by public insurance. The increase in the frequency and rate of lung transplantation for CWP is consistent with the rising prevalence of severe CWP among U.S. coal miners. Effective exposure controls and identification of early stage CWP remain essential for protecting these workers.

Respiratory morbidity among U.S. coal miners in states outside of central Appalachia.

Recent NIOSH publications have focused on the respiratory health of coal miners in central Appalachia, yet 57% of U.S. coal miners work in other regions. We characterized respiratory morbidity in coal miners from these regions. Active coal miners working outside of central Appalachia who received chest radiographs and/or spirometry during 2005-2015 were included. Chest radiographs were classified according to International Labour Office standards and spirometry was interpreted using the American Thoracic Society guidelines. Prevalence of coal workers' pneumoconiosis (CWP) and abnormal spirometry were compared by region. A total of 103 (2.1%) miners had CWP. The eastern region had the highest prevalence (3.4%), followed by the western (1.7%), and interior (0.8%) regions. A total of 524 (9.3%) miners had abnormal spirometry. CWP occurs in all U.S. coal mining regions. Prevalence of CWP was higher in the eastern region, but lower than levels reported in central Appalachia.

Coal workers' pneumoconiosis: an Australian perspective.

Coal workers' pneumoconiosis (CWP) is an untreatable but preventable lung disease arising from chronic inhalation of coal dust. Recent reports of CWP in Queensland, along with international data, suggest that there is a resurgence in pneumoconiosis. The prevalence of CWP varies considerably between countries. In Australia, there is no mandatory reporting system and no national data on the prevalence of CWP. The symptoms and manifestations of CWP vary depending on the composition of the inhaled dust, duration of exposure, stage of disease and host-related factors. CWP may develop into progressive massive fibrosis (PMF), which can be fatal. Radiological assessment should be performed according to evidence-based standards using the ILO (International Labour Office) International Classification of Radiographs of Pneumoconioses. As preventing exposure to coal dust prevents CWP, it is important to implement and enforce appropriate standards limiting exposure. In Australia, these standards currently vary between states and are not in keeping with international understanding of the levels of coal dust that cause disease. Longitudinal screening programs are crucial for monitoring the health of coal workers to identify individuals with early-stage disease and prevent progression from mild disease to PMF. We recommend: standardisation of coal dust exposure limits, with harmonisation to international regulations; implementation of a national screening program for at-risk workers, with use of standardised questionnaires, imaging and lung function testing; development of appropriate training materials to assist general practitioners in identifying pneumoconiosis; and a system of mandatory reporting of CWP to a centralised occupational lung disease register.

Prevalence Characteristics of Coal Workers' Pneumoconiosis (CWP) in a State-Owned Mine in Eastern China.

Coal Workers’ Pneumoconiosis (CWP) is the primary occupational disease in China. However, information about the definite prevalence of CWP is only partially available. The aims of our study were to assess the prevalence characteristics of CWP in a state-owned coal mine, evaluate the effects of control measures and develop further preventive strategies for CWP. The total study population included 495 cases who were diagnosed with CWP from the construction of this coal mine to the end of October 2014. Individuals’ information, including duration of dust exposure, job titles, age as first diagnosis, stages of CWP, CWP progress, complications with pulmonary tuberculosis, death and others were collected and analyzed. The results showed that 71.11% of 495 CWP cases were stage I and 90.71% were involved in tunneling or coal mining. The mean dust exposure period in CWP patients was 26.7 years, the mean latent period was 29.3 years and the mean diagnosed age was 50.3 years old. The proportion of CWP diagnosed after ending dust exposure were remarkably increased with the time passing. Among the CWP cases, 36 (7.27%) were complicated with pulmonary tuberculosis. The mortality of patients with stage III was the highest (60.71%) (p < 0.0001). Our data obviously show that more strict policies to protect coal miners are needed to be implemented in China, especially for tunneling and mining workers.

Small mine size is associated with lung function abnormality and pneumoconiosis among underground coal miners in Kentucky, Virginia and West Virginia

ObjectivesTo describe the prevalence of lung function abnormality and coal workers’ pneumoconiosis (CWP) by mine size among underground coal miners in Kentucky, Virginia and West Virginia.MethodsDuring 2005–2012, 4491 miners completed...

Prevalence of coal workers’ pneumoconiosis in China: A systematic analysis of 2001–2011 studies

Nowadays, coal workers' pneumoconiosis (CWP) is still believed to be the main occupational disease in China. However, information on the exact prevalence of the disease is not available. Therefore, the aims of our investigation were to provide the missing information in China by conducting a systematic evaluation of published data from 2001 to 2011 and to compare the prevalence of CWP with those in other countries. Published reports about the prevalence of CWP were searched from PudMed(English language databases), Foreign Medical Journal Full-Text Service Database (FMJS, English language databases), Chinese Journal Full-Text Database (CJFD, Chinese language databases), Chongqing VIP Chinese Science and Technology Journals Database (VIP, Chinese language databases), Chinese Biomedical Literature Database (CBM, Chinese language databases) and Chinese Medical Association Journals Database (CMAJ, Chinese language databases). The quality of identified reports was strictly evaluated using predetermined inclusion and exclusion criteria. Based on these criteria, 11 reports were selected. Then, the content of these reports were reviewed and the needed information was extracted. Meta-analysis was performed on the extracted data. The R2.15.1 software was applied for statistical analysis. The total populations from these reports were 173,646 and 10,821 for dust-exposed coal workers and patients with CWP, respectively. The pooled prevalence of CWP was 6.02% (95% CI: 3.43-9.26%) and the pooled rate of CWP patients combined with tuberculosis was 10.82% (95% CI: 8.26-13.66%). The prevalence was analyzed according to the geographic areas of the study, years of the investigation, duration of dust exposure, coal rank, stages of CWP, types of work and coal-mining categories, etc. Among them, the prevalence of CWP in locally owned mines (9.86%; 95% CI: 1.25-25.17%) was significantly higher than that of state-owned mines (4.83%; 95% CI: 2.35-8.13%) (P<0.05). Publication bias was assessed by the Egger's test which showed insignificant results (P>0.05). It was concluded that the prevalence of CWP were still high in China compared to UK (0.8%, during 1998-2000) and USA (3.2% in 2000s). In addition, the conditions in locally owned mines had caused more CWP than that of state-owned mines. Our data clearly show that regulatory agencies in China need to step up their effort in implementing more rigorous policies to protect coal miners, especially those in locally owned mines.

Potential Determinants of Coal Workers’ Pneumoconiosis, Advanced Pneumoconiosis, and Progressive Massive Fibrosis Among Underground Coal Miners in the United States, 2005–2009

We better defined the distribution and determinants of coal workers' pneumoconiosis (CWP) among US underground coal miners. We obtained chest radiographs from the mobile unit of an enhanced surveillance program begun in 2005 by the National Institute for Occupational Safety and Health for underground coal miners. B Readers classified them for presence of pneumoconiosis. Miners from 15 states participated (n = 6658). The prevalence of CWP was higher in 3 states (Kentucky, 9.0%; Virginia, 8.0%; West Virginia, 4.8%) than in 12 other states (age-adjusted risk ratio [RR] = 4.5; 95% confidence interval [CI] = 3.3, 6.1). Miners in these 3 states were younger and had less mining tenure, but advanced CWP (category ≥ 2/1; RR = 8.1; 95% CI = 3.9, 16.9) and progressive massive fibrosis (RR = 10.5; 95% CI = 3.8, 29.1) was more prevalent among them. Advanced CWP and progressive massive fibrosis were more prevalent among workers at mines with fewer than 155 miners, irrespective of mining region, than among workers at larger mines. Enhanced surveillance results confirmed the persistence of severe CWP among US coal miners and documented the health consequences of inadequate dust control for miners in parts of Appalachia and at smaller mines.

Critical Review of Scientific Basis for Lowering Coal Mine Dust Exposure Level. iii. Exposure-Response Studies of Radiographic CWP

Implementation of the coal mine dust (“CMD”) interim standard of 3.0 milligrams per cubic meter (“mg/m 3 ”) in 1970 was reduced to 2.0 mg/m3 in 1972 and produced a steady decline in dust levels and prevalence of coal workers pneumoconiosis (“CWP”). Beginning in the mid-1990s, an apparent increase was reported in what was thought to be severe and rapidly progressive CWP and PMF despite stability in CMD levels. These “sentinel health” events led to further investigation and stimulated the 2010 MSHA proposal to lower the current CMD standard from 2.0 mg/m 3 to 1.0 mg/m 3 . The purpose of this study is to summarize exposure-response associations between CMD and CWP to evaluate evidence for a revised standard. There are five cohorts of UK and US coalminers with exposure-response analyses useful for assessing a proposed coal mine dust standard. Two major biases confound such an evaluation. Exposure misclassification bias occurs for exposures occurring before standards and before sampling surveillance was initiated. This bias is most obvious in the US studies where sample results collected after initiation of the standard were back-extrapolated to pre-standard time periods. The bias introduced produces a spurious steeper exposure-response slope due to overestimation of risk at higher exposure levels (>4 mg/m 3 ) and under-estimation of risk at lower exposures. Participation bias occurs in one of the US studies when survey participation rates dropped below 50% in rounds 1-4. Exposure-response evidence suggests a coal mine dust standard of 2 mg/m 3 appears to be protective from occurrence of CWP ≥2 for low rank coals. However there is excess CWP ≥2 in miners exposed to high rank coal, suggesting a lower exposure standard is needed to protect these miners.

Rapidly Progressing Coal Workers Pneumoconiosis as a Confounding Risk Factor in Assessing Coal Mine Dust Safe Exposure Levels

The US coal mine dust (“CMD”) standard is among the lowest in the world. Lowering exposures to 2 mg/m3 markedly reduced prevalence of coal workers pneumoconiosis (“CWP”). Lowering the standard to 1 mg/m3 is proposed because of a recent increase in rapidly progressive coal workers pneumoconiosis. The purpose of this report is to evaluate the characteristics of the reported rapidly progressive CWP to evaluate these findings with regard to classical characteristics of CWP and to establish whether these rapidly progressive cases call for a lowering of the CMD standard. We conclude that rapidly progressing CWP appears to be silicosis based on rapid progression of disease, the characteristics of the radiological changes observed, and the high quartz exposures experienced by these cases.

Severe Occupational Pneumoconiosis Among West Virginian Coal Miners: One Hundred Thirty-eight Cases of Progressive Massive Fibrosis Compensated Between 2000 and 2009

Miners inhale dust at work and are at a risk for coal workers pneumoconiosis (CWP), a preventable and potentially fatal lung disease. After regulations were implemented in the 1970s, declines were reported in both dust levels and the prevalence of simple and advanced CWP until about 2001, when despite stable reported dust levels, disease levels sharply increased. A structured, retrospective chart review was performed to describe the demographics and disease progression for 138 coal miners with progressive massive fibrosis (PMF) whose claims were approved by the West Virginia State Occupational Pneumoconiosis Board between January 2000 and December 2009. PMF, a complication of CWP, developed in 138 West Virginian coal miners at a mean age of 52.6 years after an average of 30 years work tenure. The time of progression averaged 12.2 years from the last normal chest radiograph until PMF was detected. Lung function declined sharply in both smokers and nonsmokers, averaging 87 mL/y for FEV(1) and 74 mL/y for FVC. The board has confirmed 21 deaths in this group. The most common job activities were operating continuous-mining machines (41%) and roof bolting (19%). Virtually all of these miners' dust exposures occurred after the implementation of current federal dust regulations. Contemporary occupational dust exposures have resulted over the past decade in rapidly progressive pneumoconiosis and massive fibrosis in relatively young West Virginian coal miners, leading to important lung dysfunction and premature death.

Coal workers' pneumoconiosis in the United States: regional differences 40 years after implementation of the 1969 Federal Coal Mine Health and Safety Act

ObjectiveTo assess whether the recent increases in the prevalence of coal workers' pneumoconiosis (CWP) in the USA reflect increased measured exposures over recent decades, and to identify other potential causative...

Trends in pneumoconiosis mortality and morbidity for the United States, 1968–2005, and relationship with indicators of extent of exposure

This surveillance report examines trends in selected pneumoconioses in the U.S. for 1968--2005 and their relationship with past indicators of extent of exposure. Numbers of deaths with asbestosis, silicosis, and coal workers' pneumoconiosis (CWP) were tabulated by time and age at death. Worker monitoring CWP prevalence data were tabulated by tenure group. Information on indicators of extent and intensity of exposure were obtained from various sources. Asbestosis deaths from 1968--2005 closely followed the historical trend in asbestos consumption, and appear to be declining in most age groups. Given appropriate exposure control, asbestosis could be eliminated by 2050. Silicosis deaths decreased substantially from 1968--2005, but levelled off after 1998 in all age groups, indicating a continuing occupational risk. In the anthracite coal region, CWP mortality has been declining rapidly. If there is no resurgence in the industry, CWP could disappear in that region by 2030. In the much larger bituminous region, deaths have declined over time but may be increasing among younger individuals. In addition, although CWP prevalence in working coal miners declined substantially from 1970 to 1994, it increased from 1995 to 2006. This indicates the need for increased vigilance in dust control in underground coal mining.

IL18 and IL18R1 polymorphisms, lung CT and fibrosis: a longitudinal study in coal miners

It has been suggested that interleukin (IL)-18 plays a role in the development of inflammatory and fibrosing lung diseases. Associations of polymorphisms in the genes coding for IL-18 (IL18 /G-656T, C-607A, G-137C, T113G, C127T) and its receptor (IL18R1 /C-69T) with coal workers' pneumoconiosis (CWP) were studied in 200 miners who were examined in 1990, 1994 and 1999. Coal-dust exposure was assessed according to job history and ambient measures. The main health outcome was lung computed tomography (CT) score in 1990. Internal coherence was assessed by studying CT score in 1994, 4-yr change in CT score and CWP incidence and prevalence. CT score in 1990 was a good predictor of radiographic grade in 1999 and, therefore, an appropriate subclinical quantitative trait. The IL18 -137C allele was associated with lower CT score in 1990 and 1994 (1.24 versus 1.69 and 1.57 versus 2.46, respectively), slower progression of CT score between 1990 and 1994 and lower pneumoconiosis prevalence in 1999 relative to the G allele (0.33 versus 0.77 and 8.2 versus 19.6%, respectively). Smoking- or dust-adjustment, and stratification on IL18R1 genotype and adjustment for haplotype effects did not change the conclusions. In conclusion, the results of the present study suggest a role for IL18 in reducing the development of this fibrosing lung disease.

Interaction of Iron and Calcium Minerals in Coals and their Roles in Coal Dust-Induced Health and Environmental Problems

Epidemiological studies using pollutant gases (e.g., SO2) and particle characteristics (e.g., elemental carbon) indicate that products of fossil fuel combustion are important contributors to particulate matter (PM)-associated hospital admissions and mortality. Coal is one of the world’s most important fossil fuels, providing 40% of electricity worldwide. Besides individuals exposed to PM in ambient air, coal mining can cause adverse health effects in workers exposed to coal dusts at the workplace. Among the respiratory diseases, coal workers’ pneumoconiosis (CWP) has received the most attention because of its clear occupational association. The field of CWP research is one of the few areas in occupational health in which considerable epidemiological data are available. This offers a good opportunity to focus on the relationship between epidemiological data and physico-chemical and/or biological characteristics of coals. The objective of this review is to assess whether some physico-chemical parameters play a role in the observed regional differences in the prevalence of CWP among various coalmine regions. We mainly concentrate on the chemical interaction of two minerals, pyrite (FeS2) and calcite (CaCO3) in the coals and their role in causing occupational lung diseases (e.g., pneumoconiosis) and other environmental problems (e.g., acid mine drainage). Therefore, understanding the chemical interaction of the two minerals in the coal may lead to the identification of the causal components in coal dusts as well as in PM. Examples from U.S.A. coals are used to illustrate the chemical interaction and geological distribution of iron and calcium minerals in various coalmine regions and how the differences in levels of these types of minerals contribute to the observed regional differences in the prevalence of CWP. Molecular mechanisms leading to the CWP development are also discussed, particular in the aspects of oxidative stress and inflammation.