Coal Workers' Pneumoconiosis Research Articles

Polymorphisms in Long Noncoding RNA H19 Contribute to the Protective Effects of Coal Workers' Pneumoconiosis in a Chinese Population.

The H19 is a kind of long noncoding RNA, which has been implicated in multiple biological functions. However, the associations between genetic variants in H19 and susceptibility of coal workers’ pneumoconiosis (CWP) have been seldom reported. In the present study, three potential polymorphisms (rs2067051, rs217727, and rs2839702) in H19 were genotyped in a case-control study including 703 CWP cases and 705 controls. We found that individuals with the H19 rs2067051 CT/TT genotypes showed a decreased risk of CWP compared with those with the CC genotype (adjusted OR = 0.64, 95%CI = 0.49–0.83, p = 0.001). Further stratified analyses revealed that the associations between variant genotypes of rs2067051 and the risk of CWP were more prominent in subjects of non-smokers (adjusted OR = 0.55, 95%CI = 0.39–0.79, p = 0.001) and CWP patients with Stage I (adjusted OR = 0.63, 95%CI = 0.46–0.86, p = 0.004). Additionally, the protective effects of H19 rs2067051 were also evident in coal miners both with dust exposure years <25 years (adjusted OR = 0.63, 95%CI = 0.42–0.95, p = 0.026) and ≥25 years (adjusted OR = 0.57, 95%CI = 0.40–0.80, p = 0.001). Our results indicated that rs2067051 in the H19 gene is correlated with a deceased risk of CWP in a Chinese population, which may be a potential genetic marker for prevention and intervention of CWP. Further functional studies are warranted to validate our findings.

Plasma LncRNA-ATB, a Potential Biomarker for Diagnosis of Patients with Coal Workers' Pneumoconiosis: A Case-Control Study.

LncRNA-ATB (lncRNA was activated by transforming growth factor-β) has been reported to be involved in specific physiological and pathological processes in human diseases, and could serve as biomarkers for cancers. However, the role of lncRNA-ATB in coal workers’ pneumoconiosis (CWP) is still unknown. This study aimed to investigate the association between lncRNA-ATB and CWP. Quantitative real-time polymerase chain reaction was performed to detect plasma lncRNA-ATB expression in 137 CWP patients, 72 healthy coal miners and 168 healthy controls. LncRNA-ATB was significantly upregulated in CWP (p < 0.05). Compared with the healthy controls and healthy coal miners, the odds ratios (ORs) (95% confidence interval (CI)) for CWP were 2.57 (1.52–4.33) and 2.17 (1.04–4.53), respectively. LncRNA-ATB was positively associated with transforming growth factor-β1 (TGF-β1) (r = 0.30, p = 0.003) and negative correlated with vital capacity (VC) (r = −0.18, p = 0.033) and forced vital capacity (FVC) (r = −0.18, p = 0.046) in CWP patients. Compared with healthy controls, the area under the curve (AUC) was 0.84, resulting in a 71.17% sensitivity and 88.14% specificity. When compared with healthy coal miners, the AUC was 0.83, the sensitivity and specificity were 70.07% and 86.36%, respectively. LncRNA-ATB expression is commonly increased in CWP and significantly correlates with the TGF-β1 in CWP patients. Furthermore, elevated lncRNA-ATB was associated with CWP risk and may serve as a potential biomarker for CWP.

HSP70 gene polymorphism on genetic susceptibility to the coal worker's penumoconiosis of han nationality in Xinjiang, China.

Objective: To explore the influence of heat shock protein 70 (HSP70) gene genetic susceptibility of coal worker's pneumoconiosis among the han nationality in xinjiang. Methods: 156 coal worker's pneumoconiosis patients and 96 mine workers were randomly selected from the han coal worker's pneumoconiosis patients and attend the health check retirement mine workers from March to December, 2014 in Xinjiang Uygur Autonomous Region of Occupational Disease Hospital. Using TaqMan genotyping methods to detect HSP70 genotype distribution in the two groups. Results: The HSP70-1+190 loci GC genotype occurrence frequencies of coal worker's pneumoconiosis was significantly higher than the control group (χ2=6.75, P<0.05) , the risk of coal worker's pneumoconiosis armed with HSP70-1+190 GC genotype individual was 2.21 times of CC genotype individual (95%CI: 1.03~4.75) , and HSP70-2+1267 and HSP70-hom+2437 loci polymorphism were no significant difference between the two groups (HSP70-2+1267: χ2=3.30, P=0.19; HSP70-hom+2437: χ2=0.12, P=0.94) . Conclusion: HSP70-1+190 GC genotypes may be a susceptible genotype, the genotype individual may be more likely to suffer from coal worker's pneumoconiosis.

A solitary anthracotic lower lobe lung mass mimicking lung malignancy: an unusual presentation

Pneumoconiosis in coal workers is seen as small nodular aggregations of anthracotic macrophages in the collagen network, which are known as coal macules, with larger aggregations known as coal nodules/mass with or without fibrosis. These are usually seen around the initial site of coal dust accumulation that is the upper regions around respiratory bronchioles; however, in our case the anthracotic mass is present in the anterior basal segment of the lower lobe of the left lung. Although coal workers’ pneumoconiosis is a form of pneumoconiosis that is a common affliction of coal workers and/or chronic smokers. In our patient, prior exposure to biomass fuel exhaust seems to be the only risk factor. We present the case of an 80-year-old man presenting with fever and cough of 4 months’ duration. On evaluation, he was found to have a well-defined mass lesion in the anterior basal segment of the lower lobe of the left lung, which on core biopsy revealed features consistent with an anthracotic mass.

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.

Platelet Indices in Patients with Coal Workers' Pneumoconiosis.

Coal workers' pneumoconiosis (CWP) is caused by an accumulation of coal particles in the lung parenchyma. Reactive oxygen species (ROS) play an important role in the pathogenesis of CWP. It is well documented that ROS stimulate platelet activation, adhesion, and aggregation. The aim of the present study was to investigate the relationship between platelet indices and CWP. The demographic features, occupational and medical history, exposure time, and complete blood count of retired coal miners were retrospectively analysed. The control group comprised healthy subjects who had not worked underground. Chest radiographs were evaluated according to the CWP classification of the International Labour Office. The study population was divided into following groups: 50 controls, 97 without CWP, 142 simple pneumoconiosis (SP), 157 progressive massive fibrosis (PMF). The platelet count, mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) were significantly higher in patients with CWP compared to those in patients without CWP and controls. The platelet count, MPV, and PCT were higher in patients with PMF compared to those in the SP group (p<0.05). The results of multiple logistic regression analyses indicated that the platelet count, MPV, and PCT were independently associated with the development of CWP. Platelet indices may be considered as disease markers for pneumoconiosis in coal miners and as a useful indicator of the progression of pneumoconiosis.

Estimates and Predictions of Coal Workers' Pneumoconiosis Cases among Redeployed Coal Workers of the Fuxin Mining Industry Group in China: A Historical Cohort Study.

This research was aimed at estimating possible Coal workers’ pneumoconiosis (CWP) cases as of 2012, and predicting future CWP cases among redeployed coal workers from the Fuxin Mining Industry Group. This study provided the scientific basis for regulations on CWP screening and diagnosis and labor insurance policies for redeployed coal workers of resource-exhausted mines. The study cohort included 19,116 coal workers. The cumulative incidence of CWP was calculated by the life-table method. Possible CWP cases by occupational category were estimated through the average annual incidence rate of CWP and males’ life expectancy. It was estimated that 141 redeployed coal workers might have suffered from CWP as of 2012, and 221 redeployed coal workers could suffer from CWP in the future. It is crucial to establish a set of feasible and affordable regulations on CWP screening and diagnosis as well as labor insurance policies for redeployed coal workers of resource-exhausted coal mines in China.

Lung transplantation is increasingly common among patients with coal workers' pneumoconiosis.

The prevalence of coal workers' pneumoconiosis (CWP) in U.S. coal miners has increased, and severe presentations are increasingly common. We describe trends in lung transplantation during 1996-2014 for recipients with a primary diagnosis of CWP or pneumoconiosis unspecified, and we summarize recipient characteristics and estimate survival. A total of 47 transplants were included; nearly three-quarters were performed during 2008-2014. All recipients were male, 96% were white, and the mean age was 56 years. Mean FEV1 % was 35%; mean FVC% was 53%. Mean time on a waitlist was 155 days, and 60% of transplants were bilateral. Median survival was 3.7 years. These transplants reflect the use of a scarce resource for an entirely preventable disease, and highlight the need for enhanced efforts to reduce coal mine dust exposures.

Optical Estimation on Pollution Level of Respirable Dust Based on Infrared Transmitting Behavior in Coalmine Fully Mechanized Working Face

Respirable coal particle generated during underground mining is the main cause for gas-dust explosions and coal workers’ pneumoconiosis (CWP) which needs accurate monitoring especially on its concentration. Focusing on the coal dust pollution in the fully mechanized working face of Huangbaici coalmine, coal particle was sampled for further industrial analysis and FT-IR test to obtain its chemical composition and optical constant. Combined with the simulated spatial distribution of airborne dust, the spectral transmission characteristics of coal dust within wavelengths of 2.5 to 25 μm under different operating conditions were obtained. The simulation results show that the transmittance and aerosol optical depth (AOD) of coal dust are closely linked and obviously influenced by the variation of dust generation source (intensity of dust release, position of coal cutting, and the wetting of the coal seam) and airflow field (wind speed and direction of ventilation). Furthermore, an optical channel of 1260–1280 cm−1(7.937–7.813 μm) which is almost only sensitive to the variation of dust concentration but dull to the diameter change of coal dust was selected to establish the correlation of dust concentration and infrared transmittance. The fitting curve was then applied to retrieve the equivalent dust concentration based on optical information, and the comparison results demonstrate that the estimated pollution level is consistent with field measurement data in engineering practice.

ACR Appropriateness Criteria Review ACR Appropriateness Criteria® Occupational Lung Diseases.

Occupational lung disease is a category of disease entities characterized by a reaction of the lung parenchyma to inhaled aerosolized particles found in the environment. This document summarizes the imaging appropriateness data for silicosis, coal worker pneumoconiosis, and asbestosis. The main points of the document are that computed tomography is more sensitive than radiography, computed tomography without contrast generally suffices for evaluation, and fluorodeoxyglucose-positron emission tomography may have utility in patients with mesothelioma. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review includes an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Modifying influence of occupational inflammatory diseases on the level of chromosome aberrations in coal miners.

Coal miners are exposed to a wide range of genotoxic agents that can induce genome damage. In addition, miners are characterised by a high risk of the initiation of different occupational inflammatory as well as non-inflammatory diseases. The aim of this investigation is to analyse the modifying influence of occupational pulmonary inflammatory diseases on the level of chromosome aberrations (CAs) in miners working in underground coal mines in Kemerovo Region (Russian Federation). The study group included 90 coal miners with the following pulmonary diseases: chronic dust-induced bronchitis (CDB) and coal-workers' pneumoconiosis (CWP) (mean age = 53.52±2.95 years; mean work experience in coal-mining conditions = 27.70±3.61 years). As a population control (control 1), we have used venous blood extracted from 124 healthy unexposed men. The mean age in this group was 50.92±4.56 years. Control 2 was the venous blood extracted from 42 healthy coal miners (mean age = 51.56±6.38 years; mean work experience in coal-mining conditions = 25.43±8.14 years). We have discovered that coal miners are characterised by an increased general level of CAs as well as an increased frequency of several types of CAs. The significant increase in the frequency of aberration per 100 cells and aberration of chromosome type was discovered in the group of pulmonary disease patients (study group). No correlations of the level of chromosome damage with age, smoking status and work experience in coal-mining conditions were discovered.

Profusion of Opacities in Simple Coal Worker's Pneumoconiosis Is Associated With Reduced Lung Function

A large body of evidence demonstrates dose-response relationships of cumulative coal mine dust exposure with lung function impairment and with small-opacity profusion. However, medical literature generally holds that simple coal worker's pneumoconiosis (CWP) is not associated with lung function impairment. This study examines the relationship between small-opacity profusion and lung function in US underground coal miners with simple CWP. Miners were examined during 2005 to 2013 as part of the Enhanced Coal Workers' Health Surveillance Program. Work histories were obtained, and chest radiographs and spirometry were administered. Lung parenchymal abnormalities consistent with CWP were classified according to International Labor Organization guidelines, and reference values for FEV1 and FVC were calculated using reference equations derived from the third National Health and Nutrition Examination Survey. Differences in lung function were evaluated by opacity profusion, and regression models were fit to characterize associations between profusion and lung function. A total of 8,230 miners were eligible for analysis; 269 had category 1 or 2 simple CWP. Decrements in FEV1 % predicted were nearly consistent across profusion subcategories. Clear decrements in FVC % predicted and FEV1/FVC were also observed, although these were less consistent. Controlling for smoking status, BMI, and mining tenure, each 1-unit subcategory increase in profusion was associated with decreases of 1.5% (95% CI, 1.0%-1.9%), 1.0% (95% CI, 0.6%-1.3%), and 0.6% (95% CI, 0.4%-0.8%) in FEV1 % predicted, FVC % predicted, and FEV1/FVC, respectively. We observed progressively lower lung function across the range of small-opacity profusion. These findings address a long-standing question in occupational medicine and point to the importance of medical surveillance and respiratory disease prevention in this workforce.

Associations of MMP1, MMP2 and MMP3 Genes Polymorphism with Coal Workers’ Pneumoconiosis in Chinese Han Population

Coal workers’ pneumoconiosis (CWP) has been associated with abnormalities in the extracellular matrix remodeling, as well as aberrant matrix metalloproteinases (MMPs) in lung tissues. We investigated the association of three functional polymorphisms in MMP gene promoters (MMP1 rs1799750, MMP2 rs2285053 and MMP3 rs522616) with the risk of CWP. A total of 693 CWP cases and 690 controls were included in a case-control study. Genotype analysis was performed by the TaqMan method. Statistically significant differences were found in distributions of MMP3 rs522616 under a recessive model (p = 0.047) between CWP cases and controls. In the stratification analysis, individuals with MMP3 rs522616 GG genotype decreased the risk of CWP (adjusted OR = 0.72, 95% CI = 0.52–0.99) compared to those with AA/AG genotype obviously, particularly among subgroups of no smokers (adjusted OR = 0.64, 95% CI = 0.41–1.00). Furthermore, serum MMP3 protein levels measured with enzyme-linked immune-sorbent assay in the control group was significantly lower than that in the CWP groups (p = 0.02). Extremely lower MMP3 among subjects with the rs522616 GG or AG genotype compared with the AA genotype carriers (p < 0.05, p < 0.01 respectively) in the normal serum. These findings indicate that the MMP3 rs522616 polymorphism may contribute to the etiology of CWP in the Chinese population and MMP3 might be a potential diagnostic biomarker for CWP, additional independent studies are warranted to validate our findings in different populations as well as in a larger series.

An approach to adjust standardized mortality ratios for competing cause of death in cohort studies.

PurposeThe calculation of standardized mortality ratios (SMRs) is a standard tool for the estimation of health risks in occupational epidemiology. An increasing number of studies deal with the analysis of the mortality in employees suffering from an occupational disease like silicosis or coal-worker pneumoconiosis (CWP). Their focus lies not on the mortality risk due to the occupational disease itself, but on other diseases such as lung cancer or heart diseases. Using population-based reference rates in these studies can cause misleading results because mortality rates of the general population do not reflect the elevated mortality due to the occupational disease investigated. Hence, the purpose of the present paper is to develop an approach to adjust the risk estimates for other causes of death with respect to the effect of an occupational disease as a competing cause of death in occupational mortality cohort studies.MethodsTo overcome the problems associated with SMRs, the paper makes use of proportional mortality ratios (PMR), which are a further approach for the estimation of health risks in occupational epidemiology. The cause-specific SMR can be rewritten as a product of PMR times the overall SMR. The PMR can be adjusted by ignoring the competing cause of death. Hence, an adjusted cause-specific SMR can be derived by multiplying this adjusted PMR with the overall SMR. This approach is applied to studies concerning lung cancer risk in coal miners suffering from CWP.Results and conclusionsThe usual approach for calculating SMRs leads to an underestimation of the real lung cancer risk in subgroups of miners suffering from CWP. The same effect can be observed in workers exposed to respirable silica already suffering from silicosis. The presented approach results in more realistic risk estimation in mortality cohort studies of employees suffering from an occupational disease. It is easily calculable on the basis of usually published values of observed cases and the corresponding cause-specific SMR.

Associations of MMP-7 and OPN gene polymorphisms with risk of coal workers’ pneumoconiosis in a Chinese population: a case-control study

Background: The matrix metalloproteinase-7 (MMP-7) and osteopontin (OPN) are both multifunctional proteins with roles in inflammation, cell proliferation, tissue remodeling and so on, implicated in the pathogenesis of numerous conditions including pulmonary fibrosis. In this study, we investigated the associations between the potential functional polymorphisms in MMP-7 and OPN and the risk of coal workers’ pneumoconiosis (CWP) in a Chinese population.Methods: Four polymorphisms (rs10502001 in MMP-7, rs1126772, rs11728697 and rs9138 in OPN) were genotyped and analyzed in a case-control study of 697 CWP and 694 control subjects.Results: Our results revealed that three single nucleotide polymorphisms (SNPs, MMP-7 rs10502001, OPN rs1126772 and OPN rs11728697) were associated with increased risk of CWP under a recessive model (adjusted odds ratio [OR] = 1.80, 95% confidence interval [CI] = 1.01–3.20, p = 0.045 for MMP-7 rs10502001; adjusted OR = 2.09, 95% CI = 1.17–3.72, p = 0.013 for OPN rs1126772; adjusted OR = 2.48, 95% CI = 1.37–4.51, p = 0.003 for OPN rs11728697). Additionally, a combined effect was observed in a dose-dependent manner with increasing numbers of risk variant alleles (Ptrend = 0.003). Furthermore, logistic regression analysis revealed no significant interaction between SNPs and smoking status on CWP risk.Conclusions: Our results indicate that three functional SNPs (MMP-7 rs10502001, OPN rs11728697 and OPN rs1126772) are associated with an increased risk of CWP in a Chinese population.

Patterns of pneumoconiosis mortality in Kentucky: Analysis of death certificate data.

Mortality rates associated with total pneumoconiosis, including coal worker's pneumoconiosis (CWP), have remained elevated. 2003-2013 pneumoconiosis mortality data obtained from National Center for Health Statistics and 2011-2013 Kentucky death certificates were analyzed. Total pneumoconiosis mortality rates showed significant linear decreases in West Virginia, Pennsylvania, Kentucky, and the U.S. from 2003 to 2013; Pennsylvania and Kentucky had comparable rates in 2003 but while Pennsylvania rates significantly decreased ∼3.0 deaths/million annually, Kentucky rates decreased only 0.5/million annually. Kentucky and Pennsylvania CWP fatality rates were also comparable in 2003 but while Pennsylvania rates decreased 82% over the study period, Kentucky rates decreased only 26%. Kentucky pneumoconiosis deaths primarily occurred in white Appalachian males in-hospital. Diseases leading to pneumoconiosis death were largely respiratory and cardiovascular, with autopsies rarely performed. Coal worker environmental exposure protection should be enhanced and pneumoconiosis surveillance improvements, including enhanced management of comorbid conditions like COPD, should be considered.

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.

Gene variance in microsomal epoxide hydrolase and the susceptibility of coal workers' pneumoconiosis

To explore whether the tagging single nucleotide polymorphisms (SNPs) within EPHX1 gene were involved in the genetic susceptibility to coal worker's pneumoconiosis (CWP) by case-control study. This study consisted of 697 CWP patients and 694 controls. All the subjects were Han Chinese, underground coal miners and recruited from coal mines of Xuzhou Mining Business Group Co Ltd.. The venous blood samples were obtained from all subjects and extracted genome DNA from the isolated leucocytes. Three SNPs were selected from the HapMap and the genotyping was done by the TaqMan method with the ABI 7900HT Real Time PCR system. The Single SNP analyses showed that the genotype frequencies of EPHX1 (rs2234922) was significantly associated with decreased risk of CWP under co-dominant model (OR = 0.22, 95% CI = 0.06~0.79, P = 0.020), recessive model (OR = 0.23, 95% CI = 0.06~0.82, P = 0.023), and addictive model (OR = 0.75, 95% CI = 0.58~0.96, P = 0.022). The further stratification analysis showed that the risk of CWP will significantly decreased in non-smoking groups (OR = 0.10, 95% CI = 0.01~0.83, P = 0.033). Our results suggest that individuals with the EPHX1 (rs223492) GG genotype was associated with a dereased risk of CWP, and it has a protective effect on the developing CWP.

Clinical analysis of thoracoscopy of 30 coalworker's pneumoconiosiswith pleural effusion cases

To investigate the diagnostic value of thoracoscopy on idiopathic coalworker's pneumoconiosis with pleural effusion in general medicine. Routine (general medicine) thoracoscopyof patients suffering from iIdiopathiccoalworker's pneumoconiosis with pleural effusion, pathological examination of lesions obtained (direct vision). Pathological examination revealed grayish-white miliary nodules with multiple protruding nodules, irregular focal pleura thickening, pulmonary congestion, edema, fibrous adhesion. Thorascopy produced a diagnostic rate of 93.3%. Confirmed cases includes 13 cases of tuberculous pleurisy, 11 cases of malignant pleural effusion, 4 cases of cardiac insufficiency with pleural effusion and 2 cases of idiopathic pleural effusion, with no serious complications. Thoracoscopy of idiopathic coalworker's pneumoconiosis with pleural effusion is a safe, accurate diagnostic methodin general medicine, and could benefit the establishment of a treatment method quickly, visual observation of the lesions of patients suffering from coalworker's pneumoconiosis with pleural effusion using thoracoscopy, and at the same time offer preliminary investigationof the correlation between the intensity and compactibilityof coal macule distribution and clinical stages of coalworker's Pneumoconiosis.

Comparison of the Cumulative Incidence Rates of Coal Workers' Pneumoconiosis between 1970 and 2013 among Four State-Owned Colliery Groups in China.

The purpose of this study was to identify differences in the incidence characteristics of coal workers’ pneumoconiosis (CWP) based on data from four large state-owned colliery groups of China, by comparing the cumulative incidence rates of CWP. We investigated 87,904 coal workers from the Datong, Kailuan, Fuxin, and Tiefa Colliery Groups, who were exposed to dust for at least 1 year. The cumulative incidence rate of CWP was calculated with the life-table method and stratified analysis among coal workers with different occupational categories during different years of first dust exposure. Our results showed the cumulative incidence rate of Datong was higher than that of any other colliery group among workers with different occupational categories during different years of first dust exposure. For Datong workers who started their dust exposure in the 1970s, the cumulative incidence rates of CWP among tunneling, mining, combining, and helping workers were 34.77%, 10.20%, 34.59%, and 4.91% during the observed time of 34 years, respectively. For those in the 1980s, the cumulative incidence rates were 32.29%, 13.51%, 2.98%, and 0.47%, respectively. The cumulative incidence rates of Fuxin and Tiefa were the lowest. In conclusion, the Datong colliery has the highest cumulative incidence rate of CWP among the four studied collieries, followed by Kailuan. The cumulative incidence rates of Fuxin and Tiefa were the lowest. Additional dust-proofing measures for decreasing dust concentrations are still necessary.