The impacts of coal dust on miners' health: A review

The hospitalisation risk of chronic circulatory and respiratory diseases associated with coal mining in the general population in Queensland, Australia

Queensland is the main coal mining state in Australia where populations in coal mining areas have been historically exposed to coal mining emissions. Although a higher risk of chronic circulatory and respiratory diseases has been associated with coal mining globally, few studies have investigated these associations in the Queensland general population. This study estimates the association of coal production with hospitalisations for chronic circulatory and respiratory diseases in Queensland considering spatial and temporal variations during 1997-2014. An ecological analysis used a Bayesian hierarchical spatiotemporal model to estimate the association of coal production with standardised rates of each, chronic circulatory and respiratory diseases, adjusting for sociodemographic factors and considering the spatial structure of Queensland's statistical areas (SA2) in the 18-year period. Two specifications; with and without a space-time interaction effect were compared using the integrated nested Laplace approximation -INLA approach. The posterior mean of the best fit model was used to map the spatial, temporal and spatiotemporal trends of risk. The analysis considered 2,831,121 hospitalisation records. Coal mining was associated with a 4 % (2.4-5.5) higher risk of hospitalisation for chronic respiratory diseases in the model with a space-time interaction effect which had the best fit. An emerging higher risk of either chronic circulatory and respiratory diseases was identified in eastern areas and some coal-mining areas in central and southeast Queensland. There were important disparities in the spatiotemporal trend of risk between coal -and non-coal mining areas for each, chronic circulatory and respiratory diseases. Coal mining is associated with an increased risk of chronic respiratory diseases in the Queensland general population. Bayesian spatiotemporal analyses are robust methods to identify environmental determinants of morbidity in exposed populations. This methodology helps identifying at-risk populations which can be useful to support decision-making in health. Future research is required to investigate the causality links between coal mining and these diseases.

An evaluation of pyrite as a component of respirable coal dust

Over the past two decades, the rise in coal worker's pneumoconiosis has prompted research into the effects of respirable coal dust components. This study explores how coal-pyrites produce hydroxyl radicals (•OH), a reactive oxygen species closely associated with particle toxicity, and assesses the ability of safe chemical additives to reduce •OH production at various pH levels. Promising candidates were evaluated in various solutions, including tap and process waters and simulated lung fluid. We employed electrokinetic measurements, infrared and X-ray photoelectron spectroscopies, and ab initio atomistic simulations to analyze particle surfaces. The study also looked at how surface aging affects •OH production. Our results show that •OH generation of the pyrite varies and is catalyzed by elements like silicon, aluminum, and iron in pyrite. Carboxymethyl cellulose was effective in reducing •OH production by targeting surface sulfide and silicon sites and affecting surface hydration and charge. Atmospheric aging was found to increase •OH production, especially in the pyrite with high iron and silicon and low calcium contents, relative to other samples. This highlights the role of the pyrite surface properties and chemical composition, and the solution pH and composition in •OH generation by coal-pyrites.

A comprehensive evaluation method for dust pollution: Digital image processing and deep learning approach

Dust pollution poses a grave threat to both the environment and human health, especially in mining operations. To combat this issue, a novel evaluation method is proposed, integrating grayscale average (GA) analysis and deep learning (DL) in image classification. By utilizing a self-designed dust diffusion simulation system, 300 sample images were generated for analysis. The GA method establishes a correlation between grayscale average and dust mass, while incorporating fractal dimension (FD) enhances classification criteria. Both GA and DL methods were trained and compared, yielding promising results with a testing accuracy of 92.2 % and high precision, recall, and F1-score values. This approach not only demonstrates efficacy in classifying dust pollution but also presents a versatile solution applicable beyond mining to diverse dust-contaminated work environments. By combining image processing and deep learning, it offers an automated and reliable system for environmental monitoring, thereby enhancing safety standards and health outcomes in affected industries. Ultimately, this innovative method signifies a significant advancement towards mitigating dust pollution and ensuring sustainable industrial practices.

Research progress on the pathogenesis and prediction of pneumoconiosis among coal miners

Pneumoconiosis is the most common occupational disease among coal miners, which is a lung disease caused by long-term inhalation of coal dust and retention in the lungs. The early stage of this disease is highly insidious, and pulmonary fibrosis may occur in the middle and late stages, leading to an increase in patient pain index and mortality rate. Currently, there is a lack of effective treatment methods. The pathogenesis of pneumoconiosis is complex and has many influencing factors. Although the characteristics of coal dust have been considered the main cause of different mechanisms of pneumoconiosis, the effects of coal dust composition, particle size and shape, and coal dust concentration on the pathogenesis of pneumoconiosis have not been systematically elucidated. Meanwhile, considering the irreversibility of pneumoconiosis progression, early prediction for pneumoconiosis patients is particularly important. However, there is no early prediction standard for pneumoconiosis among coal miners. This review summarizes the relevant research on the pathogenesis and prediction of pneumoconiosis in coal miners in recent years. Firstly, the pathogenesis of coal worker pneumoconiosis and silicosis was discussed, and the impact of coal dust characteristics on pneumoconiosis was analyzed. Then, the early diagnostic methods for pneumoconiosis have been systematically introduced, with a focus on image collaborative computer-aided diagnosis analysis and biomarker detection. Finally, the challenge of early screening technology for miners with pneumoconiosis was proposed.

Prevalence of nano-sized coal mine dust in North and Central Appalachian coal mines - Insights from SEM-EDS imaging

The increasing prevalence of coal mine dust-related lung diseases in coal miners calls for urgent and meticulous scrutiny of airborne respirable coal mine dust (RCMD), specifically focusing on particles at the nano-level. This necessity is driven by expanding research, including the insights revealed in this paper, that establish the presence and significantly increased toxicity of nano-sized coal dust particles in contrast to their larger counterparts. This study presents an incontrovertible visual proof of these tiny particulates in samples collected from underground mines, utilizing advanced techniques such as scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The intricate elemental composition of nano-sized coal dust identified through EDS analysis reveals the presence of elements such as silica and iron, which are known to contribute to lung pathologies when inhaled over prolonged periods. The outcomes of the statistical analyses reveal significant relationships between particle size and elemental composition, highlighting that smaller particles tend to have higher carbon content, while larger particles exhibit increased concentrations of elements like silica and aluminum. These analyses underscore the complex interactions within nano-sized coal dust, providing critical insights into their behavior, transport, and health impacts. The nano-sized coal dust could invade the alveoli, carrying these toxic elements from where they are impossible to exhale. The revelation of nano-sized coal dust's existence and the associated health hazards necessitate their incorporation into the regulatory framework governing the coal mining industry. This study lays the groundwork for heightened protective measures for miners, urging the invention of state-of-the-art sampling instruments, comprehensive physicochemical profiling of RCMD nanoparticles, and the pursuit of groundbreaking remedies to neutralize their toxic impact. These findings advocate for a paradigm shift in how the coal mining industry views and handles particulate matter, proposing a re-evaluation of occupational health standards and a call to action for protecting coal miners worldwide.

Spatial and temporal distribution characteristics of dust concentration based on satellite in mining area

The spatial and temporal distribution patterns of dust concentration in the Pingshuo mining area and urban area were analyzed utilizing satellite data. The results indicate that the correlation coefficients of the average PM2.5 and PM10 concentration retrieved by satellite in Shuozhou City are 0.88 and 0.63, respectively, and the satellite inversion data demonstrate high reliability. The spatial distribution of dust concentration in the Pingshuo Mine area is elevated during winter and spring, with significant dust accumulation in winter. The pollution phenomenon in the Pingshuo mining area was pronounced from January to March, and the air quality deteriorated significantly. The correlation analysis of dust concentration between the city and the mining area reveals a marked spatial discontinuity at the boundary between the city and the mining area, indicating that the mining area is not the primary cause of the increase of dust concentration in the urban area, and changes in dust concentration within the mining area exert no significant impact on the urban area. The research results possess significant implications for dust control in both the mining and urban areas.

A microscopic mechanism study of the effect of binary surfactants on the flotation of Wiser bituminous coal

Investigating surfactant effects on the floatability of Wiser bituminous coal holds significant importance in improving coal cleanliness and utilization value. Using density functional theory and molecular dynamics simulation methods, this study constructed models of Wiser bituminous coal and examined the impact of different surfactants, including the anionic surfactant sodium dodecyl benzene sulfonate, the cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB), and the non-ionic surfactant fatty alcohol ethoxylated ether. The focus was on investigating the charge distribution characteristics of these molecules and the modifying effect of binary surfactants on the hydrophobicity of bituminous coal. Results revealed that the maximum electrostatic potential was concentrated near oxygen/nitrogen/sulfur-containing functional groups like sulfonic acid groups, quaternary ammonium cations, ethylene oxide, hydroxyl groups, carboxyl groups, and sulfur bonds. These functional groups exhibited a propensity for accepting/delivering electrons to form hydrogen bonds. Among the surfactants tested, CTAB revealed the slightest difference in frontier orbital energy, measuring 3.187 eV, thereby demonstrating a superior trapping ability compared with the other two surfactants. Adsorption reactions within the system were determined to be spontaneous, with over 60% of the interaction force attributed to electrostatic forces. Moreover, the repulsive force magnitude with water molecules followed the trend: sulfonate group (2.20 Å) < ethylene oxide (2.43 Å) < quaternary ammonium cation (2.57 Å), indicating more excellent water repellency of CTAB. Findings showed that CTAE binary surfactants proved most effective in modifying the hydrophobicity of bituminous coal. This study offers valuable insights into reducing waste, pollution, and resource wastage.

Conversion of metal-enriched magnetite mine tailings into suitable soil for vegetation by phytoremediation process with Bougainvillaea glabra under the influence of Thiobacillus ferroxidance

Magnetite mining is a significant contributor to land deterioration as well as HM-based soil contamination. The characteristics of magnetite mine tailing were examined in the present study, in addition to the positive and sustainable restoration strategy with Bougainvillaea glabra under the influence of Thiobacillus ferroxidance. The traits of test soil analysis findings demonstrated that the majority of the parameters exceeded the allowable limits (For instance: HMs such as Cr, Cu, Zn, Pb, Fe, and Co were found to be 208 ± 2.3, 131.43 ± 1.6, 185.41 ± 3.3, 312 ± 5.11, 956 ± 5.3, and 26.89 ± 2.43 mg kg-1 respectively). T. ferroxidance exhibited impressive HMs tolerance for as much as 800 g mL-1 concentrations of Cr, Cu, Zn, Pb, Fe, and Co. To prevent HMs toxic effects, the HMs contents in test soil were decreased by diluting with normal soil in the ratios of Ex-3 and Ex-2. A typical greenhouse study was carried out to assess the phytoremediation ability of B. glabra across six setups for experiments (Ex-1 to Ex-6). According to the findings of this research, the HMs tolerant T. ferroxidance from Ex-3 and Ex-2 had an outstanding impact on the growth, biomolecules level (such as chlorophylls: 65.84 & 41.1 mg g-1, proteins: 165.1 & 151.1 mg g-1, as well as carbohydrates: 227.4 & 159.3 mg g-1) as well as phytoremediation potential of B. glabra on magnetite mine soil. These findings indicated that a mixture of B. glabra as well as T. ferroxidance might serve as a valuable sustainable agent for removing HMs from contaminated soil.

Black Lung Disease Among Coal Miners in Asia: A Systematic Review

Background

Coal miners are highly prone to occupational health risks, such as black lung disease. This study aims to assess the prevalence of black lung disease and the factors associated with black lung disease among coal miners in Asia.

Method

This systematic review, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, searched through the scientific literature of the following databases: EBSCO, ScienceDirect, PubMed, and Scopus. We selected articles that studied black lung disease among coal miners from 48 countries in Asia and were published between 2014 and 2023. Article quality was evaluated using the Critical Appraisal Skills Program.

Result

The seven articles that we review studied a total of 653,635 coal miners from various types of coal mines from three countries in Asia. Of these miners, 59,998 experienced black lung disease. Black lung disease is prevalent among 9.18% of coal miners in Asia, which is approximately four times higher than the worldwide prevalence. Common factors that influence black lung disease in Asia include age, years of dust exposure, smoking, drinking, working types, and sizes of mines, type of mines, respiratory functions, spirometry parameters, tenure, lack of attention to occupational health, inefficient surveillance, and weak occupational health service.

Conclusion

Although the prevalence of black lung disease among coal miners in Asia is considerably high, it can be addressed through effective prevention measures, monitoring, control, and case reporting.

Associations of coal mine dust exposure with arterial stiffness and atherosclerotic cardiovascular disease risk in chinese coal miners

OBJECTIVE

Whether coal mine dust exposure increases cardiovascular diseases (CVDs) risk was rarely explored. Our objective was to examine the association between coal mine dust exposure and cardiovascular risk.

METHODS

We estimated cumulative coal mine dust exposure (CDE) for 1327 coal miners by combining data on workplace dust concentrations and work history. We used brachial-ankle pulse wave velocity (baPWV, a representative indicator of arterial stiffness) and ten-year atherosclerotic cardiovascular disease (ASCVD) risk to assess potential CVD risk, exploring their associations with CDE.

RESULTS

Positive dose-response relationships of CDE with baPWV and ten-year ASCVD risk were observed after adjusting for covariates. Specifically, each 1 standard deviation (SD) increase in CDE was related to a 0.27 m/s (95% CI: 0.21, 0.34) increase in baPWV and a 1.29 (95% CI: 1.14, 1.46) elevation in OR (odds ratio) of risk of abnormal baPWV. Moreover, each 1 SD increase in CDE was associated with a 0.74% (95% CI: 0.63%, 0.85%) increase in scores of ten-year ASCVD and a 1.91 (95% CI: 1.62, 2.26) increase in OR of risk of ten-year ASCVD. When compared with groups unexposed to coal mine dust, significant increase in the risk of arterial stiffness and ten-year ASCVD in the highest CDE groups were detected.

CONCLUSION

The study suggested that cumulative exposure to coal mine dust was associated with elevated arterial stiffness and ten-year ASCVD risk in a dose-response manner. These findings contribute valuable insights for cardiovascular risk associated with coal mine dust.

Exploring the determinants of health-promoting behaviors among miners: A text mining and meta-analysis

The health-promoting behaviors of miners are of great significance to their physical and mental well-being. With a focus on enhancing their overall health, this study aimed to explore the determinants and influencing mechanisms of health-promoting behaviors in miners. Initially, the latent Dirichlet allocation (LDA) model was utilized to extract topical keywords from literature over the last 23 years and to categorize the determinants based on integrating the health promotion model and the health belief model. Subsequently, a meta-analysis was performed based on 51 related empirical research to explore the mechanisms between determinants and health-promoting behaviors. The results indicated that (1) the factors influencing miners' health-promoting behaviors can be divided into four dimensions: physical environment, psychosocial environment, individual characteristics, and health beliefs. (2) Noise was negatively related to health-promoting behaviors, while protective equipment, health culture, interpersonal relationships, health literacy, health attitudes, and income were positively related to health-promoting behaviors. (3) Protective equipment and health literacy were positively related to perceived threat, whereas interpersonal relationships were positively related to perceived benefits. This study sheds light on the mechanisms influencing miners' health-promoting behaviors and could inform behavioral interventions in occupational health.

Comparative toxicity of coal and coal ash: Assessing biological impacts and potential mechanisms through in vitro and in vivo testing

BACKGROUND

Coal and coal ash present inorganic elements associated with negative impacts on environment and human health. The objective of this study was to compare the toxicity of coal and coal ash from a power plant, assess their inorganic components, and investigate the biological impacts and potential mechanisms through in vitro and in vivo testing.

METHODS

Particle-Induced X-ray Emission method was used to quantify inorganic elements and the toxicity was evaluated in Caenorhabditis elegans and Daphnia magna in acute and chronic procedures. The genotoxic potential was assessed using alkaline and FPG-modified Comet assay in HepG2 cells and mutagenicity was evaluated using Salmonella/microsome assay in TA97a, TA100, and TA102 strains.

RESULTS

Inorganic elements such as aluminum (Al) and chromium (Cr) were detected at higher concentrations in coal ash compared to coal. These elements were found to be associated with increased toxicity of coal ash in both Caenorhabditis elegans and Daphnia magna. Coal and coal ash did not induce gene mutations, but showed genotoxic effects in HepG2 cells, which were increased using the FPG enzyme, indicating DNA oxidative damage.

CONCLUSIONS

The combined findings from bioassays using C. elegans and D. magna support the higher toxicity of coal ash, which can be attributed to its elevated levels of inorganic elements. The genotoxicity observed in HepG2 cells confirms these results. This study highlights the need for continuous monitoring in areas affected by environmental degradation caused by coal power plants. Additionally, the analysis reveals significantly higher concentrations of various inorganic elements in coal ash compared to coal, providing insight into the specific elemental composition contributing to its increased toxicity.

The role of macrophage polarization and related key molecules in pulmonary inflammation and fibrosis induced by coal dust dynamic inhalation exposure in Sprague-Dawley rats

Coal dust is the main occupational hazard factor during coal mining operations. This study aimed to investigate the role of macrophage polarization and its molecular regulatory network in lung inflammation and fibrosis in Sprague-Dawley rats caused by coal dust exposure. Based on the key exposure parameters (exposure route, dose and duration) of the real working environment of coal miners, the dynamic inhalation exposure method was employed, and a control group and three coal dust groups (4, 10 and 25 mg/m3) were set up. Lung function was measured after 30, 60 and 90 days of coal dust exposure. Meanwhile, the serum, lung tissue and bronchoalveolar lavage fluid were collected after anesthesia for downstream experiments (histopathological analysis, RT-qPCR, ELISA, etc.). The results showed that coal dust exposure caused stunted growth, increased lung organ coefficient and decreased lung function in rats. The expression level of the M1 macrophage marker iNOS was significantly upregulated in the early stage of exposure and was accompanied by higher expression of the inflammatory cytokines TNF-α, IL-1β, IL-6 and the chemokines IL-8, CCL2 and CCL5, with the most significant trend of CCL5 mRNA in lung tissues. Expression of the M2 macrophage marker Arg1 was significantly upregulated in the mid to late stages of coal dust exposure and was accompanied by higher expression of the anti-inflammatory cytokines IL-10 and TGF-β. In conclusion, macrophage polarization and its molecular regulatory network (especially CCL5) play an important role in lung inflammation and fibrosis in SD rats exposed to coal dust by dynamic inhalation.

The dangerous link between coal dust exposure and DNA damage: unraveling the role of some of the chemical agents and oxidative stress

Exposure to coal mining dust poses a substantial health hazard to individuals due to the complex mixture of components released during the extraction process. This study aimed to assess the oxidative potential of residual coal mining dust on human lymphocyte DNA and telomeres and to perform a chemical characterization of coal dust and urine samples. The study included 150 individuals exposed to coal dust for over ten years, along with 120 control individuals. The results revealed significantly higher levels of DNA damage in the exposed group, as indicated by the standard comet assay, and oxidative damage, as determined by the FPG-modified comet assay. Moreover, the exposed individuals exhibited significantly shorter telomeres compared to the control group, and a significant correlation was found between telomere length and oxidative DNA damage. Using the PIXE method on urine samples, significantly higher concentrations of sodium (Na), phosphorus (P), sulfur (S), chlorine (Cl), potassium (K), iron (Fe), zinc (Zn), and bromine (Br) were observed in the exposed group compared to the control group. Furthermore, men showed shorter telomeres, greater DNA damage, and higher concentrations of nickel (Ni), calcium (Ca), and chromium (Cr) compared to exposed women. Additionally, the study characterized the particles released into the environment through GC-MS analysis, identifying several compounds, including polycyclic aromatic hydrocarbons (PAHs) such as fluoranthene, naphthalene, anthracene, 7H-benzo[c]fluorene, phenanthrene, pyrene, benz[a]anthracene, chrysene, and some alkyl derivatives. These findings underscore the significant health risks associated with exposure to coal mining dust, emphasizing the importance of further research and the implementation of regulatory measures to safeguard the health of individuals in affected populations.

Suspension characteristics of the coal-quartz dust mixture in the working environment during the fully mechanized mining process

Dust exposures during mining activity can result in lung diseases such as coal workers' pneumoconiosis (CWP) and silicosis, and it is closely related to quartz dust. In the present study, coal-quartz dust mixture were investigated considering the particle size and the specific constituents. Multiple numerical techniques, including computational fluid dynamics and discrete element method (CFD-DEM), hard sphere model, and direct Monte Carlo simulation (DSMC), were presented, and the dust diffusion processes were investigated. According to the validation of the numerical method, the suspension characteristics of the polydisperse mixed dust were analyzed in detail. The results show that PM10 responds quickly, has a large diffusion range, and is easily affected by the reflux. The particle size increases gradually from top to bottom. When the air velocity is low, the percentage of coal dust in the breathing zone tends to be 50%. The results provide theoretical guidance for the comprehensive prevention of the mixed dust in underground coal mines.

Analysis of the dust-methane two-phase coupling blowdown effect at different air duct positions in an excavation anchor synchronous tunnel

Bolter miners are being increasingly used. Unfortunately, this mining technology causes a considerable amount of air pollution (especially by methane and dust) during excavation. In this study, the multiphase coupling field of airflow-dust-methane for different distances between the pressure air outlet and the working face (Lp) was simulated by using the FLUENT software. The migration law of pollutants in the multiphase coupling field was analyzed, and the distance parameters between the pressure air outlet and the working face were optimized. Finally, the simulation results were verified based on the field measurement results. We found that the blowdown effect was more obvious when 14 m ≤ Lp < 16 m compared with other conditions. The peak value of dust concentration within this distance range was the smallest (44.4% lower than the highest peak value, which was verified when Lp = 18 m), while the methane concentration was < 0.6%. A high-concentration area (where methane concentration > 0.75%), identified near the walking part of the bolter miner, was 13 m shorter than the largest (when Lp = 18 m). Therefore, we determined that the optimal blowdown distance would be 14 m ≤ Lp < 16 m. Within this range, the dust removal and methane dilution effects are optimal, effectively improving the tunnel air quality and providing a safe and clean environment for mine workers.

The evaluation analysis on the airborne dust regional pollution of the anchor drilling operation in the tunnel

The anchor drilling operations generate massive airborne dust particles in the tunnel heading face that raises the pneumoconiosis morbidity and explosion risk. In this paper, a full-scale tunnel physical model is constructed to study the effect of the wind velocity and drilling site position on the airborne dust regional pollution scope based on the actual anchor drilling craft. The research indicates that the four extensive vortex areas keep the dust suspension at 14 m from the heading face and make the deposition dust particle refloat. The average respirable dust rate reaches the maximum value at section 5 m and presents a gradual decline as the dust particle migrates along the outlet direction. Raising the wind velocity contributes to alleviating the airborne dust pollution in the anchor drilling operation. As the wind velocity increases from 3 to 24 m/s, the high dust concentration area and number higher than 200 mg/m³ pose overall decrease trends, and the average dust concentration displays a linear decrease until 26.14-58.65 mg/m³ around the anchor worker head. Moving the drilling site positions closer to the exhaust air duct aggravates the airborne dust pollution in the front breathing zone. As the anchor drilling operation switches from the return air side to the supply air side, the dust concentration area ascends by 59.4-84.4% in the personnel respiratory space.

Heavy metal pollution in Mongolian-Manchurian grassland soil and effect of long-range dust transport by wind

Grasslands provide a range of valuable ecosystem services, but they are also particularly fragile ecosystems easily threatened by human activities, such as long-term open-pit mining and related industrial activities. In grassland area, dust containing heavy metal(loid)s generated by mines may further migrate to remote places, but few studies have focused on the long-range transport of contaminants as an important pollution source. In the present study, one of the largest and most intact grassland ecosystems, the Mongolian-Manchurian steppe, was selected to investigate its pollution status and track potential sources. A total of 150 soil samples were collected to explore reginal distribution of nine heavy metal(loid)s that has potential risk in grassland. We conducted a combined multi-variant analysis of positive matrix factorization (PMF) and machine learning, which foregrounded the source of long-range transport of contaminants and inspired the hypothesis of a novel stochastic model to describe contaminants distribution. Results showed four different sources accounting for 44.44% (parent material), 20.28% (atmospheric deposition), 20.39% (farming), and 14.89% (transportation) of the total concentration, respectively. Factor 2 indicated that coal surface mining lead to a significant enrichment of As and Se with their concentration far above the global average level, which was different from other reported grassland areas. Machine learning results further confirmed that atmospheric and topographic features were their contamination controlling factors. The model results proposed that As, Se and Cu released by surface mining will be transported over long distance under prevailing monsoon, until finally deposited in the windward slope of mountain due to terrain obstruction. The long-range transport by wind and deposition of contaminants may be a prevailing phenomenon in temperate grassland, making it a pollution source that cannot be ignored. Evidence from this study reveals the urgency of precautions for fragile grassland ecosystems around industrial areas and provides a basis for its management and risk control policies.

Coal-source acid mine drainage reduced the soil multidrug-dominated antibiotic resistome but increased the heavy metal(loid) resistome and energy production-related metabolism

A recent global scale study found that mining-impacted environments have multi-antibiotic resistance gene (ARG)-dominated resistomes with an abundance similar to urban sewage but much higher than freshwater sediment. These findings raised concern that mining may increase the risk of ARG environmental proliferation. The current study assessed how typical multimetal(loid)-enriched coal-source acid mine drainage (AMD) contamination affects soil resistomes by comparing with background soils unaffected by AMD. Both contaminated and background soils have multidrug-dominated antibiotic resistomes attributed to the acidic environment. AMD-contaminated soils had a lower relative abundance of ARGs (47.45 ± 23.34 ×/Gb) than background soils (85.47 ± 19.71 ×/Gb) but held high-level heavy metal(loid) resistance genes (MRGs, 133.29 ± 29.36 ×/Gb) and transposase- and insertion sequence-dominated mobile genetic elements (MGEs, 188.51 ± 21.81 ×/Gb), which was 56.26 % and 412.12 % higher than background soils, respectively. Procrustes analysis showed that the microbial community and MGEs exerted more influence on driving heavy metal(loid) resistome variation than antibiotic resistome. The microbial community increased energy production-related metabolism to fulfill the increasing energy needs required by acid and heavy metal(loid) resistance. Horizontal gene transfer (HGT) events primarily exchanged energy- and information-related genes to adapt to the harsh AMD environment. These findings provide new insight into the risk of ARG proliferation in mining environments.

Spatial and temporal evolution of mine dust research: visual knowledge mapping analysis in Web of Science from 2001 to 2021

Dust pollution control is the basic guarantee of mine safety production, which has been widely concerned by scholars. Based on a total of 1786 publications collected by the Web of Science Core Collection (WOSCC) from 2001 to 2021, this paper analyzes the spatial-temporal distribution characteristics, hot topics, and frontier trends of the international mine dust field during the past 20 years by using Citespace and VOSviewer knowledge graph technology. The research shows that the study of mine dust can be divided into three stages: initial period (2001 ~ 2008), stable transition period (2009 ~ 2016), and boom period (2017 ~ 2021). The journals and disciplines which belong to mine dust research mainly focus on environmental science and engineering technology. A stable core group of authors and institutions have been preliminarily formed in the dust research field. The main themes of the study contained the whole process of mine dust generation, transport, prevention, and control, as well as the consequences of disaster. At present, the hot research fields mainly focus on mine dust particle pollution, multi-stage dust prevention, and emission reduction technologies, and mine occupational protection, monitoring, and early warning. In the future, the research should focus on the mechanism of dust production and transportation, the theory of efficient prevention and control, the technology and equipment of precise prevention and control of dust, and the high-precision monitoring and early warning of dust concentration. Future research should be concerned with dust control in underground mines and deep concave open-pit mines with complicated and treacherous environments, and strengthen research institutions, interdisciplinary cooperation, and interaction so as to promote the integration and application of mine dust and automation, information, and intelligent technology.

Anomalous Enrichment of As and Hg in Underground Coal Dust: A Case from Xishan Coalfield, Shanxi Province, North China

Coal dust is an important source of coal workers' pneumoconiosis, which is harmful to the health of underground workers. The coal dust samples were directly collected using a coal dust sampler from four major production positions in the underground coal mine. The particle size distribution, mineralogy, and occurrence of As and Hg in the coal dust samples were investigated. The results indicated that the contents of As and Hg were depleted or normal in the parent coal samples compared with the average values of C-P coal in North China and Chinese coal, but they were anomalously enriched in coal dusts. The concentrations of As and Hg in the coal dust samples studied are greater than the values of the elements in the parent coal. The As content in the coal dust samples studied is about one to three orders of magnitude above the parent coal value and the Hg content in the studied coal is 1.28 to 20.28 times higher than the parent coal value. The modes of occurrences of As and Hg were studied by sequential chemical extraction in combination with field emission scanning electron microscopy-energy dispersive spectroscopy (FESEM-EDS) and high-resolution transmission electron microscopy-EDS (HRTEM-EDS). The occurrence of As is dominated mainly by pyrite and secondarily by carbonate and silicate in the coal dust samples. Pyritic Hg and organic Hg may be the dominant forms in mining face and heading face samples, and carbonate and pyritic Hg are the main forms in rocks roadway and return airway samples. It is considered that the mechanochemical effect resulted in the formation of surface active sites and modification of the morphology. Harmful trace elements, such as As, Cd, Hg, Se, Pb, Co, Sb, and Tl, and minor grains associated with nanominerals that bear much hazardous elements, could easily be originally fractionated or adsorbed by airborne particulates. This research aims to provide a theoretical basis for the prevention of occupational disease and underground environmental evaluation.

Metagenomic analysis characterizes resistomes of an acidic, multimetal(loid)-enriched coal source mine drainage treatment system

Heavy metal(loid) contaminations caused by mine activities are potential hot spots of antibiotic resistance genes (ARGs) because of heavy metal(loid)-induced co-selection of ARGs and heavy metal(loid) resistance genes (MRGs). This study used high-throughput metagenomic sequencing to analyze the resistome characteristics of a coal source acid mine drainage passive treatment system. The multidrug efflux mechanism dominated the antibiotic resistome, and a highly diverse heavy metal(loid) resistome was dominated by mercury-, iron-, and arsenic--associated resistance. Correlation analysis indicated that mobile gene elements had a greater influence on the dynamic of MRGs than ARGs. Among the metagenome-assembled genomes, six potential pathogens carrying multiple resistance genes resistant to several antibiotics and heavy metal(loid)s were recovered. Pseudomonas spp. contained the highest numbers of resistance genes, with resistance to two types of antibiotics and 12 types of heavy metal(loid)s. Thus, high contents of heavy metal(loid)s drove the co-selection of ARGs and MRGs. The occurrence of potential pathogens containing multiple resistance genes might increase the risk of ARG dissemination in the environment.

Health damage assessment of reconstruction dust from old industrial buildings under multi-process

The regeneration of old industrial buildings produces considerable construction dust, thereby seriously threatening the occupational health of construction workers. The existing articles concerning the exposure and health impacts of reconstruction dust in enclosed spaces are limited, but this research field has received increasing attention. In this study, multi-process during the demolition and reinforcement stages of a reconstruction project were monitored to determine the respirable dust concentration distribution. A questionnaire survey was conducted to obtain the exposure parameters of reconstruction workers. Moreover, a health damage assessment system for the reconstruction process of old industrial buildings was established by applying the disability-adjusted life year and human capital method to explore the health damage caused by the generated dust at different stages to the construction personnel. The assessment system was applied to the reconstruction stage of an old industrial building regeneration project in Beijing to obtain dust health damage values for different work types and to conduct comparative analysis. The results indicate that there are significant differences in the dust concentration and health damage at different stages. During the demolition stage, the manual demolition of concrete structures has the highest dust concentration, reaching 0.96 mg/m³. This exceeds the acceptable concentration by 37%, and the health damage cost is 0.58 yuan per person per day. In the reinforcement stage, the dust concentration generated by mortar/concrete mixing is the highest, but the risk level is acceptable. The health damage cost of concrete grinding, which is 0.98 yuan per person per day, is the highest. Therefore, it is necessary to strengthen the protective facilities and improve the reconstruction technology to reduce dust pollution. The results of this study can help in improving the existing dust pollution control measures at construction sites to reduce the risk of dust hazards during reconstruction.

Diversity of soil bacteria in alpine coal slag mountain grassland in different vegetation restoration years

Purpose

This study aimed to investigate changes in the bacterial diversity of the rhizosphere soil of slag mountains in different years of revegetation restoration.

Methods

Seven soil samples were selected from different years of revegetation restoration in Qinghai, China. The bacterial community of each soil was analyzed via high-throughput sequencing using the Illumina MiSeq platform.

Results

Statistical analyses revealed that the diversity of the soil bacterial community was higher in the soil that was restored in 2017 than that in the soils restored from other years. 16S rRNA sequencing revealed that Proteobacteria and Actinobacteria were the dominant phyla. Sphingomonas was the dominant genus. Total nitrogen, available nitrogen, and total potassium influenced the horizontal community structure of the phylum, whereas total nitrogen, organic matter, and pH had a great influence on the horizontal community structure of the phylum. The richness and diversity of the bacterial community in the soils that underwent revegetation restoration were greater in the third year (2017) than in other years. In the seventh year of recovery, the richness and diversity of the bacterial community began to decline.

Conclusion

The bacterial diversity of the soil in the coal mine slag mountain improved with the increase in vegetation restoration years.

The dependence of particle size on cell toxicity for modern mining dust

Progressive massive pulmonary fibrosis among coal miners has unexpectedly increased. It would likely due to the greater generation of smaller rock and coal particles produced by powerful equipment used in modern mines. There is limited understanding of the relationship between micro- or nanoparticles with pulmonary toxicity. This study aims to determine whether the size and chemical characteristics of typical coal-mining dust contribute to cellular toxicity. Size range, surface features, morphology, and elemental composition of coal and rock dust from modern mines were characterized. Human macrophages and bronchial tracheal epithelial cells were exposed to mining dust of three sub- micrometer and micrometer size ranges at varying concentrations, then assessed for cell viability and inflammatory cytokine expression. Coal had smaller hydrodynamic size (180–3000 nm) compared to rock (495–2160 nm) in their separated size fractions, more hydrophobicity, less surface charge, and consisted of more known toxic trace elements (Si, Pt, Fe, Al, Co). Larger particle size had a negative association with in-vitro toxicity in macrophages (p < 0.05). Fine particle fraction, approximately 200 nm for coal and 500 nm for rock particles, explicitly induced stronger inflammatory reactions than their coarser counterparts. Future work will study additional toxicity endpoints to further elucidate the molecular mechanism causing pulmonary toxicity and determine a dose–response curve.

The Minderoo-Monaco Commission on Plastics and Human Health

Background

Plastics have conveyed great benefits to humanity and made possible some of the most significant advances of modern civilization in fields as diverse as medicine, electronics, aerospace, construction, food packaging, and sports. It is now clear, however, that plastics are also responsible for significant harms to human health, the economy, and the earth's environment. These harms occur at every stage of the plastic life cycle, from extraction of the coal, oil, and gas that are its main feedstocks through to ultimate disposal into the environment. The extent of these harms not been systematically assessed, their magnitude not fully quantified, and their economic costs not comprehensively counted.

Goals

The goals of this Minderoo-Monaco Commission on Plastics and Human Health are to comprehensively examine plastics' impacts across their life cycle on: (1) human health and well-being; (2) the global environment, especially the ocean; (3) the economy; and (4) vulnerable populations-the poor, minorities, and the world's children. On the basis of this examination, the Commission offers science-based recommendations designed to support development of a Global Plastics Treaty, protect human health, and save lives.

Report Structure

This Commission report contains seven Sections. Following an Introduction, Section 2 presents a narrative review of the processes involved in plastic production, use, and disposal and notes the hazards to human health and the environment associated with each of these stages. Section 3 describes plastics' impacts on the ocean and notes the potential for plastic in the ocean to enter the marine food web and result in human exposure. Section 4 details plastics' impacts on human health. Section 5 presents a first-order estimate of plastics' health-related economic costs. Section 6 examines the intersection between plastic, social inequity, and environmental injustice. Section 7 presents the Commission's findings and recommendations.

Plastics

Plastics are complex, highly heterogeneous, synthetic chemical materials. Over 98% of plastics are produced from fossil carbon- coal, oil and gas. Plastics are comprised of a carbon-based polymer backbone and thousands of additional chemicals that are incorporated into polymers to convey specific properties such as color, flexibility, stability, water repellence, flame retardation, and ultraviolet resistance. Many of these added chemicals are highly toxic. They include carcinogens, neurotoxicants and endocrine disruptors such as phthalates, bisphenols, per- and poly-fluoroalkyl substances (PFAS), brominated flame retardants, and organophosphate flame retardants. They are integral components of plastic and are responsible for many of plastics' harms to human health and the environment.Global plastic production has increased almost exponentially since World War II, and in this time more than 8,300 megatons (Mt) of plastic have been manufactured. Annual production volume has grown from under 2 Mt in 1950 to 460 Mt in 2019, a 230-fold increase, and is on track to triple by 2060. More than half of all plastic ever made has been produced since 2002. Single-use plastics account for 35-40% of current plastic production and represent the most rapidly growing segment of plastic manufacture.Explosive recent growth in plastics production reflects a deliberate pivot by the integrated multinational fossil-carbon corporations that produce coal, oil and gas and that also manufacture plastics. These corporations are reducing their production of fossil fuels and increasing plastics manufacture. The two principal factors responsible for this pivot are decreasing global demand for carbon-based fuels due to increases in 'green' energy, and massive expansion of oil and gas production due to fracking.Plastic manufacture is energy-intensive and contributes significantly to climate change. At present, plastic production is responsible for an estimated 3.7% of global greenhouse gas emissions, more than the contribution of Brazil. This fraction is projected to increase to 4.5% by 2060 if current trends continue unchecked.

Plastic Life Cycle

The plastic life cycle has three phases: production, use, and disposal. In production, carbon feedstocks-coal, gas, and oil-are transformed through energy-intensive, catalytic processes into a vast array of products. Plastic use occurs in every aspect of modern life and results in widespread human exposure to the chemicals contained in plastic. Single-use plastics constitute the largest portion of current use, followed by synthetic fibers and construction.Plastic disposal is highly inefficient, with recovery and recycling rates below 10% globally. The result is that an estimated 22 Mt of plastic waste enters the environment each year, much of it single-use plastic and are added to the more than 6 gigatons of plastic waste that have accumulated since 1950. Strategies for disposal of plastic waste include controlled and uncontrolled landfilling, open burning, thermal conversion, and export. Vast quantities of plastic waste are exported each year from high-income to low-income countries, where it accumulates in landfills, pollutes air and water, degrades vital ecosystems, befouls beaches and estuaries, and harms human health-environmental injustice on a global scale. Plastic-laden e-waste is particularly problematic.

Environmental Findings

Plastics and plastic-associated chemicals are responsible for widespread pollution. They contaminate aquatic (marine and freshwater), terrestrial, and atmospheric environments globally. The ocean is the ultimate destination for much plastic, and plastics are found throughout the ocean, including coastal regions, the sea surface, the deep sea, and polar sea ice. Many plastics appear to resist breakdown in the ocean and could persist in the global environment for decades. Macro- and micro-plastic particles have been identified in hundreds of marine species in all major taxa, including species consumed by humans. Trophic transfer of microplastic particles and the chemicals within them has been demonstrated. Although microplastic particles themselves (>10 µm) appear not to undergo biomagnification, hydrophobic plastic-associated chemicals bioaccumulate in marine animals and biomagnify in marine food webs. The amounts and fates of smaller microplastic and nanoplastic particles (MNPs <10 µm) in aquatic environments are poorly understood, but the potential for harm is worrying given their mobility in biological systems. Adverse environmental impacts of plastic pollution occur at multiple levels from molecular and biochemical to population and ecosystem. MNP contamination of seafood results in direct, though not well quantified, human exposure to plastics and plastic-associated chemicals. Marine plastic pollution endangers the ocean ecosystems upon which all humanity depends for food, oxygen, livelihood, and well-being.

Human Health Findings

Coal miners, oil workers and gas field workers who extract fossil carbon feedstocks for plastic production suffer increased mortality from traumatic injury, coal workers' pneumoconiosis, silicosis, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer. Plastic production workers are at increased risk of leukemia, lymphoma, hepatic angiosarcoma, brain cancer, breast cancer, mesothelioma, neurotoxic injury, and decreased fertility. Workers producing plastic textiles die of bladder cancer, lung cancer, mesothelioma, and interstitial lung disease at increased rates. Plastic recycling workers have increased rates of cardiovascular disease, toxic metal poisoning, neuropathy, and lung cancer. Residents of "fenceline" communities adjacent to plastic production and waste disposal sites experience increased risks of premature birth, low birth weight, asthma, childhood leukemia, cardiovascular disease, chronic obstructive pulmonary disease, and lung cancer.During use and also in disposal, plastics release toxic chemicals including additives and residual monomers into the environment and into people. National biomonitoring surveys in the USA document population-wide exposures to these chemicals. Plastic additives disrupt endocrine function and increase risk for premature births, neurodevelopmental disorders, male reproductive birth defects, infertility, obesity, cardiovascular disease, renal disease, and cancers. Chemical-laden MNPs formed through the environmental degradation of plastic waste can enter living organisms, including humans. Emerging, albeit still incomplete evidence indicates that MNPs may cause toxicity due to their physical and toxicological effects as well as by acting as vectors that transport toxic chemicals and bacterial pathogens into tissues and cells.Infants in the womb and young children are two populations at particularly high risk of plastic-related health effects. Because of the exquisite sensitivity of early development to hazardous chemicals and children's unique patterns of exposure, plastic-associated exposures are linked to increased risks of prematurity, stillbirth, low birth weight, birth defects of the reproductive organs, neurodevelopmental impairment, impaired lung growth, and childhood cancer. Early-life exposures to plastic-associated chemicals also increase the risk of multiple non-communicable diseases later in life.

Economic Findings

Plastic's harms to human health result in significant economic costs. We estimate that in 2015 the health-related costs of plastic production exceeded $250 billion (2015 Int$) globally, and that in the USA alone the health costs of disease and disability caused by the plastic-associated chemicals PBDE, BPA and DEHP exceeded $920 billion (2015 Int$). Plastic production results in greenhouse gas (GHG) emissions equivalent to 1.96 gigatons of carbon dioxide (CO2e) annually. Using the US Environmental Protection Agency's (EPA) social cost of carbon metric, we estimate the annual costs of these GHG emissions to be $341 billion (2015 Int$).These costs, large as they are, almost certainly underestimate the full economic losses resulting from plastics' negative impacts on human health and the global environment. All of plastics' economic costs-and also its social costs-are externalized by the petrochemical and plastic manufacturing industry and are borne by citizens, taxpayers, and governments in countries around the world without compensation.

Social Justice Findings

The adverse effects of plastics and plastic pollution on human health, the economy and the environment are not evenly distributed. They disproportionately affect poor, disempowered, and marginalized populations such as workers, racial and ethnic minorities, "fenceline" communities, Indigenous groups, women, and children, all of whom had little to do with creating the current plastics crisis and lack the political influence or the resources to address it. Plastics' harmful impacts across its life cycle are most keenly felt in the Global South, in small island states, and in disenfranchised areas in the Global North. Social and environmental justice (SEJ) principles require reversal of these inequitable burdens to ensure that no group bears a disproportionate share of plastics' negative impacts and that those who benefit economically from plastic bear their fair share of its currently externalized costs.

Conclusions

It is now clear that current patterns of plastic production, use, and disposal are not sustainable and are responsible for significant harms to human health, the environment, and the economy as well as for deep societal injustices.The main driver of these worsening harms is an almost exponential and still accelerating increase in global plastic production. Plastics' harms are further magnified by low rates of recovery and recycling and by the long persistence of plastic waste in the environment.The thousands of chemicals in plastics-monomers, additives, processing agents, and non-intentionally added substances-include amongst their number known human carcinogens, endocrine disruptors, neurotoxicants, and persistent organic pollutants. These chemicals are responsible for many of plastics' known harms to human and planetary health. The chemicals leach out of plastics, enter the environment, cause pollution, and result in human exposure and disease. All efforts to reduce plastics' hazards must address the hazards of plastic-associated chemicals.

Recommendations

To protect human and planetary health, especially the health of vulnerable and at-risk populations, and put the world on track to end plastic pollution by 2040, this Commission supports urgent adoption by the world's nations of a strong and comprehensive Global Plastics Treaty in accord with the mandate set forth in the March 2022 resolution of the United Nations Environment Assembly (UNEA).International measures such as a Global Plastics Treaty are needed to curb plastic production and pollution, because the harms to human health and the environment caused by plastics, plastic-associated chemicals and plastic waste transcend national boundaries, are planetary in their scale, and have disproportionate impacts on the health and well-being of people in the world's poorest nations. Effective implementation of the Global Plastics Treaty will require that international action be coordinated and complemented by interventions at the national, regional, and local levels.This Commission urges that a cap on global plastic production with targets, timetables, and national contributions be a central provision of the Global Plastics Treaty. We recommend inclusion of the following additional provisions:The Treaty needs to extend beyond microplastics and marine litter to include all of the many thousands of chemicals incorporated into plastics.The Treaty needs to include a provision banning or severely restricting manufacture and use of unnecessary, avoidable, and problematic plastic items, especially single-use items such as manufactured plastic microbeads.The Treaty needs to include requirements on extended producer responsibility (EPR) that make fossil carbon producers, plastic producers, and the manufacturers of plastic products legally and financially responsible for the safety and end-of-life management of all the materials they produce and sell.The Treaty needs to mandate reductions in the chemical complexity of plastic products; health-protective standards for plastics and plastic additives; a requirement for use of sustainable non-toxic materials; full disclosure of all components; and traceability of components. International cooperation will be essential to implementing and enforcing these standards.The Treaty needs to include SEJ remedies at each stage of the plastic life cycle designed to fill gaps in community knowledge and advance both distributional and procedural equity.This Commission encourages inclusion in the Global Plastic Treaty of a provision calling for exploration of listing at least some plastic polymers as persistent organic pollutants (POPs) under the Stockholm Convention.This Commission encourages a strong interface between the Global Plastics Treaty and the Basel and London Conventions to enhance management of hazardous plastic waste and slow current massive exports of plastic waste into the world's least-developed countries.This Commission recommends the creation of a Permanent Science Policy Advisory Body to guide the Treaty's implementation. The main priorities of this Body would be to guide Member States and other stakeholders in evaluating which solutions are most effective in reducing plastic consumption, enhancing plastic waste recovery and recycling, and curbing the generation of plastic waste. This Body could also assess trade-offs among these solutions and evaluate safer alternatives to current plastics. It could monitor the transnational export of plastic waste. It could coordinate robust oceanic-, land-, and air-based MNP monitoring programs.This Commission recommends urgent investment by national governments in research into solutions to the global plastic crisis. This research will need to determine which solutions are most effective and cost-effective in the context of particular countries and assess the risks and benefits of proposed solutions. Oceanographic and environmental research is needed to better measure concentrations and impacts of plastics <10 µm and understand their distribution and fate in the global environment. Biomedical research is needed to elucidate the human health impacts of plastics, especially MNPs.

Summary

This Commission finds that plastics are both a boon to humanity and a stealth threat to human and planetary health. Plastics convey enormous benefits, but current linear patterns of plastic production, use, and disposal that pay little attention to sustainable design or safe materials and a near absence of recovery, reuse, and recycling are responsible for grave harms to health, widespread environmental damage, great economic costs, and deep societal injustices. These harms are rapidly worsening.While there remain gaps in knowledge about plastics' harms and uncertainties about their full magnitude, the evidence available today demonstrates unequivocally that these impacts are great and that they will increase in severity in the absence of urgent and effective intervention at global scale. Manufacture and use of essential plastics may continue. However, reckless increases in plastic production, and especially increases in the manufacture of an ever-increasing array of unnecessary single-use plastic products, need to be curbed.Global intervention against the plastic crisis is needed now because the costs of failure to act will be immense.

Environmental hazards posed by mine dust, and monitoring method of mine dust pollution using remote sensing technologies: An overview

The over-exploitation of mineral resources has led to increasingly serious dust pollution in mines, resulting in a series of negative impacts on the environment, mine workers (occupational health) and nearby residents (public health). For the environment, mine dust pollution is considered a major threat on surface vegetation, landscapes, weather conditions and air quality, leading to serious environmental damage such as vegetation reduction and air pollution; for occupational health, mine dust from the mining process is also regarded as a major threat to mine workers' health, leading to occupational diseases such as pneumoconiosis and silicosis; for public health, the pollutants contained in mine dust may pollute surrounding rivers, farmlands and crops, which poses a serious risk to the domestic water and food security of nearby residents who are also susceptible to respiratory diseases from exposure to mine dust. Therefore, the second section of this paper combines literature research, statistical studies, and meta analysis to introduce the public mainly to the severity of mine dust pollution and its hazards to the environment, mine workers (occupational health), and residents (public health), as well as to present an outlook on the management of mine dust pollution. At the same time, in order to propose a method for monitoring mine dust pollution on a regional scale, based on the Dense Dark Vegetation (DDV) algorithm, the third section of this paper analysed the aerosol optical depth (AOD) change in Dexing City of China using the data of 2010, 2014, 2018 and 2021 from the NASA MCD19A2 Dataset to explore the mine dust pollution situation and the progress of pollution treatment in Dexing City from 2010 to 2021. As a discussion article, this paper aims to review the environmental and health risks caused by mine dust pollution, to remind the public to take mine dust pollution seriously, and to propose the use of remote sensing technologies to monitor mine dust pollution, providing suggestions for local governments as well as mines on mine dust monitoring measures.

Experimental investigation on spontaneous combustion oxidation characteristics and stages of coal with different metamorphic degrees

Coal spontaneous combustion (CSC) is a major disaster threatening coal mine safety; therefore, the investigation of coal spontaneous combustion and oxidation characteristics has been a hot topic in the long term. In this paper, the experimental temperature programmed system is used to carry out the simulation experiment of coal spontaneous combustion and oxidation of three kinds of coal with different metamorphic degrees under three oxygen concentrations (9%, 15%, 21%). The effects of metamorphic degree and oxygen concentration on coal oxidation characteristics were analyzed, and the variation laws of crossing point temperature, three characteristic point temperature, and apparent activation energy were qualitatively discussed. Finally, coal oxidation reaction stages were evaluated and divided. The results show that the concentrations of CO and C₂H₄ are negatively correlated with the degree of deterioration but increase with the increase of oxygen concentration. High metamorphic coal corresponds to high crossing point temperature (CPT). The average error between the CPT value calculated from the BM empirical correlation and the experimental data is very small, which is 6.42%. The higher the metamorphic degree of coal, the higher the three characteristic temperature points (critical temperature, xerochasy temperature, and activity temperature). The oxidation process of the three coal samples is divided into four stages: surface oxidation, oxidation self-heating, accelerated oxidation, and deep oxidation. The apparent activation energy of each stage exhibits significant variability, with varying patterns displayed with the degree of metamorphism.

Spreading Behavior and Wetting Characteristics of Anionic Surfactant Droplets Impacting Bituminous Coal

Spraying water-based materials on the coal surface is a common means of coal dust suppression. There are obvious dynamic wetting behaviors during droplets impacting coal. To explore the spreading behavior and wetting characteristics of anionic surfactant droplets on bituminous coal, three anionic surfactants, which are sodium dodecyl sulfate (SDS), sodium dodecyl sulfonate (SDDS), and sodium dodecyl benzene sulfonate (SDBS), were used for the droplet impact experiment and molecular dynamics (MD) simulation. The results show that the addition of anionic surfactants can promote the wetting behavior of the droplet, and the difference between the head group and the tail group of the surfactant molecules can affect the wettability of the droplet. The dimensionless spreading coefficient shows the rule of SDBS > SDS > SDDS. When the concentration does not reach critical micelle concentration (CMC), the surface tension decreases and the dimensionless spreading coefficient of droplets increases with the increase of concentration. When the droplet concentration reaches the CMC, surface tension is no longer an effective indicator to evaluate the wettability of droplets. The dimensionless spreading coefficient can effectively evaluate the macroscopic spreading wetting behavior of droplets, and it is better than the surface tension. MD simulation results show that the interaction between anionic surfactants and coal molecules can affect the adsorption behavior, and the interaction energy and adhesion work are shown as the rule of SDBS < SDS < SDDS. The results of MD simulation and the impact experiment show that the intermolecular adsorption behavior has a significant influence on the spreading process. The results of MD simulation further explain the results of the droplet impact experiment.

Automated Identification of Overheated Belt Conveyor Idlers in Thermal Images with Complex Backgrounds Using Binary Classification with CNN

Mechanical industrial infrastructures in mining sites must be monitored regularly. Conveyor systems are mechanical systems that are commonly used for safe and efficient transportation of bulk goods in mines. Regular inspection of conveyor systems is a challenging task for mining enterprises, as conveyor systems' lengths can reach tens of kilometers, where several thousand idlers need to be monitored. Considering the harsh environmental conditions that can affect human health, manual inspection of conveyor systems can be extremely difficult. Hence, the authors proposed an automatic robotics-based inspection for condition monitoring of belt conveyor idlers using infrared images, instead of vibrations and acoustic signals that are commonly used for condition monitoring applications. The first step in the whole process is to segment the overheated idlers from the complex background. However, classical image segmentation techniques do not always deliver accurate results in the detection of target in infrared images with complex backgrounds. For improving the quality of captured infrared images, preprocessing stages are introduced. Afterward, an anomaly detection method based on an outlier detection technique is applied to the preprocessed image for the segmentation of hotspots. Due to the presence of different thermal sources in mining sites that can be captured and wrongly identified as overheated idlers, in this research, we address the overheated idler detection process as an image binary classification task. For this reason, a Convolutional Neural Network (CNN) was used for the binary classification of the segmented thermal images. The accuracy of the proposed condition monitoring technique was compared with our previous research. The metrics for the previous methodology reach a precision of 0.4590 and an F1 score of 0.6292. The metrics for the proposed method reach a precision of 0.9740 and an F1 score of 0.9782. The proposed classification method considerably improved our previous results in terms of the true identification of overheated idlers in the presence of complex backgrounds.

Prevalence of coal worker's pneumoconiosis: a systematic review and meta-analysis

Global prevalence trend and regional differences of coal worker's pneumoconiosis (CWP) remain unclear. This study aimed to provide systematic and comprehensive evidence for the global prevalence of CWP. Literature research for studies that reported prevalence of CWP was conducted in PubMed, CNKI, and Web of Science. The identified studies were strictly screened according to predetermined inclusion and exclusion criteria. The pooled prevalence of CWP in different periods and regions was calculated. A total of 37 studies were included after screening, and data from the Coal Workers' Health Surveillance Program was additionally included in the meta-analysis. The global pooled prevalence of CWP decreased from 23.33% (95% confidence interval [CI]: 18.03%, 28.62%) before 1970 to 6.00% (95% CI: 4.11%, 7.90%) in 1981-1990, but indicated a rebound (10.35%, 95% CI: 8.08%, 12.62%) in 1991-2000 and finally dropped to 2.29% (95% CI: 2.06%, 2.51%) in 2011-2020. In the recent 30 years, the top three pooled prevalence of CWP was found in Europe, China, and the USA, respectively. Few articles have reported the prevalence in developing regions, but available evidence indicated that the prevalence in developing regions was much higher than that in developed regions. Higher pooled prevalence was observed in studies which reported larger number of miners in collieries, older average age of miners, underground collieries, and longer dust exposure time. The global prevalence of CWP indicates a rebound in 1990s, but the overall trend is downward in the recent 60 years. The prevention and treatment of CWP should be currently emphasized in developing countries.

Predicting the risk of nodular thyroid disease in coal miners based on different machine learning models

Background

Nodular thyroid disease is by far the most common thyroid disease and is closely associated with the development of thyroid cancer. Coal miners with chronic coal dust exposure are at higher risk of developing nodular thyroid disease. There are few studies that use machine learning models to predict the occurrence of nodular thyroid disease in coal miners. The aim of this study was to predict the high risk of nodular thyroid disease in coal miners based on five different Machine learning (ML) models.

Methods

This is a retrospective clinical study in which 1,708 coal miners who were examined at the Huaihe Energy Occupational Disease Control Hospital in Anhui Province in April 2021 were selected and their clinical physical examination data, including general information, laboratory tests and imaging findings, were collected. A synthetic minority oversampling technique (SMOTE) was used for sample balancing, and the data set was randomly split into a training and Test dataset in a ratio of 8:2. Lasso regression and correlation heat map were used to screen the predictors of the models, and five ML models, including Extreme Gradient Augmentation (XGBoost), Logistic Classification (LR), Gaussian Parsimonious Bayesian Classification (GNB), Neural Network Classification (MLP), and Complementary Parsimonious Bayesian Classification (CNB) for their predictive efficacy, and the model with the highest AUC was selected as the optimal model for predicting the occurrence of nodular thyroid disease in coal miners.

Result

Lasso regression analysis showed Age, H-DLC, HCT, MCH, PLT, and GGT as predictor variables for the ML models; in addition, heat maps showed no significant correlation between the six variables. In the prediction of nodular thyroid disease, the AUC results of the five ML models, XGBoost (0.892), LR (0.577), GNB (0.603), MLP (0.601), and CNB (0.543), with the XGBoost model having the largest AUC, the model can be applied in clinical practice.

Conclusion

In this research, all five ML models were found to predict the risk of nodular thyroid disease in coal miners, with the XGBoost model having the best overall predictive performance. The model can assist clinicians in quickly and accurately predicting the occurrence of nodular thyroid disease in coal miners, and in adopting individualized clinical prevention and treatment strategies.

Study of the Micromechanism of the Effect of Fatty Alcohol Poly(oxyethylene) Ether-9 on the Wettability of Jincheng Anthracite

The influence mechanism of the adsorption of fatty alcohol poly(oxyethylene) ether (AEO₉) on the wettability of anthracite coal was studied by means of experiments and simulations. First, the contact angle and surface tension were measured. When the AEO₉ concentration was 0.5 wt %, the contact angle and surface tension were the smallest, which were 10.28° and 25.39 mN m^-1, respectively. X-ray photoelectron spectroscopy (XPS) indicated that the content of C-O functional groups on the anthracite surface increased by 20.76% after adsorption of AEO₉. The molecular orbital energy and electrostatic potential of AEO₉ and anthracite were calculated by density functional theory (DFT). There are two modes of electron transfer between the two orbitals: highest occupied molecular orbital (HOMO) transfer of AEO₉ to lowest unoccupied molecular orbital (LUMO) transfer of anthracite and HOMO transfer of anthracite to LUMO transfer of AEO₉. The dynamics simulation results show that the addition of AEO₉ increases the migration rate of water molecules, promotes the movement of a large number of water molecules toward the surface of anthracite, and enhances the thickness of the water molecular layer on the surface of anthracite. The analysis of the relative concentration shows that AEO₉ is distributed at the anthracite/water interface. AEO₉ molecules are intertwined and connected by hydrophobic chains to form a network structure, which covers the anthracite surface horizontally, thus promoting the strength of the anthracite/water interaction.

Study on the optimal parameter range of droplet-wrapped respirable dust in spray dustfall by mesoscopic method

Coal miners on the fringes of cities are often exposed to respirable dust hazards. Spray is one of the most effective dust reduction measures. When studying the coupling and collision behavior of droplets and dust particles, it is helpful to optimize the parameter range of the droplets to capture dust particles at the mesoscopic level, to determine the effect of the spray field on the dust particles at the macroscopic level. In this study, the volume of fluid (VOF) method was used to track the interface of multiphase flow. A numerical simulation of 13 working conditions was carried out using the control variable method. Based on the numerical simulation results, we obtained the optimal parameter range for dust to be encapsulated by droplets. To confirm the reliability of the simulation, we independently developed an experimental system and conducted experiments. The simulation results obtained were measured using the experimental system, and an optimal droplet parameter range of 7 μm to settle dust in a coal mining face was determined. Numerical simulation using a mesoscopic method to study dust-spray coupling produced reliable results, which can be used in the practical application of spray dust reduction and has wider relevance for practical engineering.

Influence of inclination angle on dust migration and settlement characteristics of excavation roadway

The migration law of dust in the roadway is the basis of dust control, but most of the relevant studies are based on the horizontal roadway, ignoring the roadway inclination. Therefore, numerical simulation and similar experiments are used to systematically study the settlement and diffusion law of dust in roadways with different inclination angles. The results show that the roadway inclination has little effect on the structure of the convection field, but the roadway inclination will change the law of dust transport in the roadway. In the elevation roadway, with the increase of elevation, the settling particle size and distance of dust will increase, which is conducive to dust discharge, but it will also cause secondary dust in the roadway. In the depression angle roadway, with the increase of depression angle, the particle size and distance of dust settlement decrease, which is conducive to dust settlement, but will cause dust accumulation in front of the roadway. Based on this, it is proposed to reduce the wind speed in elevation roadway and increase the wind speed in depression roadway, which provides a basis for improving the dust transport theory and prevention and control work in heading roadway.

Association of coal mine dust lung disease with Nodular thyroid disease in coal miners: A retrospective observational study in China

Background

Coal dust is a major risk factor for the occupational health of coal miners, and underground workers with coal mine dust lung disease (Coal miners with coal mine dust lung disease (CMDLD) may have a higher risk of developing Nodular thyroid disease (NTD). The aim of this study was to investigate the relationship between coal mine dust lung disease and the development of Nodular thyroid disease in coal miners.

Methods

This was a clinical retrospective observational study that included 955 male coal miners from 31 different coal mining companies in Huainan, Anhui Province, China, who were examined in April 2021 at the Huainan Occupational Disease Prevention and Control Hospital to collect all their clinical physical examination data, including general conditions, laboratory test indices and imaging indices. Based on the presence or absence of Nodular thyroid disease, 429 cases with Nodular thyroid disease were classified as the diseased group and 526 cases without Nodular thyroid disease were classified as the control group. Logistic regression was used to analyse the correlation between the occurrence of Nodular thyroid disease in coal miners, and further single- and multi-factor logistic regression was used to screen the risk exposure factors for Nodular thyroid disease in coal miners.

Results

Age, coal mine dust lung disease (CMDLD), red blood cells (RBC), mean red blood cell volume (MCV), albumin (ALB), albumin/globulin (A/G), indirect bilirubin (IBIL), globulin (GLOB), total bilirubin (TBil) and myeloperoxidase (MPO) were associated with the development of Nodular thyroid disease in coal miners (p < 0.05) The results of univariate and multifactorial logistic regression analysis showed that CMDLD (OR:4.5,95%CI:2.79-7.51) had the highest OR and CMDLD was the strongest independent risk exposure factor for the development of Nodular thyroid disease in coal miners.

Conclusions

There is a strong correlation between coal mine dust lung disease and Nodular thyroid disease in underground coal miners, and clinicians need to be highly aware of the high risk of NTD in coal miners with CMDLD and adopt individualized clinical prevention strategies.

Risk and Status of Gastrointestinal Cancer According to the International Standard Industrial Classification in Korean Workers

Simple Summary

The risk of developing cancers varies depending on occupation, which is a well-known fact. It is crucial to investigate the risk of developing gastrointestinal (GI) cancer in the entire industry. In this study, we calculated the standardized incidence ratios (SIRs) of GI cancer by all industrial sectors as classified in the Korean Standard Industrial Classification (KSIC). There were noticeable differences among industries in the risk of GI cancer. The SIR of all GI cancer was highest among miners and quarriers, and second highest among transportation workers. These results suggest that further research is required to identify the risk factors present in each industry that contribute to the development of GI cancers. We believe this study can help to create tailored cancer prevention strategies for different industrial sectors.

Abstract

To compare the risk of developing gastrointestinal (GI) cancer according to industrial groups, we performed a retrospective cohort study using the database of the Korea National Health Insurance Service (NHIS). We calculated the age-standardized incidence ratios (SIRs) and 95% confidence intervals (95% CIs) for the types of GI cancers according to the Korean Standard Industrial Classification (KSIC) compared with the whole employee population. The highest SIR for all GI cancer was found in the “Mining and quarrying” section (SIR, 1.30; 95% CI, 1.14–1.47), followed by the “Transportation and storage” section (SIR, 1.27; 95% CI, 1.24–1.30). Miners and quarriers had the highest risk of developing gastric cancer (SIR, 1.29; 95% CI, 1.06–1.55) and cancer of the liver and intrahepatic bile ducts (SIR, 1.48; 95% CI, 1.17–1.86). Transportation workers had the highest SIR of cancer of the lip, oral cavity, and pharynx (SIR, 1.27; 95% CI, 1.13–1.43) and cancers of the rectum, anus, and anal canal (SIR, 1.27; 95% CI, 1.19–1.35). There were distinct GI cancers with an elevated risk in each industry group. Our findings imply that distinct cancer prevention programs should be developed for each industrial sector.

Experimental Study on the Influence of Coal Fracture Surface Roughness on Water Injection Seepage

Coal seam water injection has a significant effect on downhole dust resistance. However, during the operation of coal seam water injection, the seepage of the solution in the coal fractures is impacted by the roughness of coal fractures. Therefore, in this study, distilled water and a sodium lauryl sulfate surfactant were used as seepage solutions, kennel coal was used as the research subject, and four coal samples with different roughness coefficients were prepared for seepage experiments. After the analysis and discussion of the experimental results, it is found that the surface roughness of coal fractures hinders the seepage effect of coal seam water injection. The greater the surface roughness of coal fractures, the smaller the permeability coefficient. Furthermore, increasing the injection pressure and fracture aperture can reduce the influence of coal fracture surface roughness on the permeability coefficient. In addition, after sodium lauryl sulfate is added, the permeability coefficient of the coal sample is reduced. This further reveals the seepage of water injection into coal seams and provides certain guidance for the development of coal seam water injection technology.

Assessment of Genetic Damage in Coal Miners of Punjab, Pakistan

Coal miners are continuously exposed to coal mine dust and airborne particulate that act as a potential risk to their health. The present study evaluates the DNA damage in coal miners using the Buccal Micronucleus Cytome (BMCyt) assay. The samples of the blood and buccal epithelial cells of 40 coal miners and 20 control subjects were taken from coal mines of Pail and Padhrar, Pakistan, to establish buccal anomaly frequencies of metal levels in the blood. Besides this, work history and duration hours were also analyzed. Results revealed that micronucleus frequencies positively correlated with the metal concentrations in the miner's blood. The change in the extent of nuclear damage per unit change in the year was 0.170 for micronuclei; however, with addition in each year of working experience, nuclear buds and broken egged nuclei increased by 0.316 and 0.194 units, where each year increases karyolysis by 0.349 units and karyorrhexis by 0.308 units, respectively. An increase in work hours and working years was positively correlated with cytogenetic damage. Nuclear damage in coal miners due to occupational exposure is obvious and increases with increasing work experience. Hence, the Buccal Micronucleus Cytome assay has proved to be an effective cytogenetic biomonitoring tool for assessing genetic and nuclear damage in coal miners.

Hazardous elements present in coal nanoparticles in a Caribbean port region in Colombia

Scientific works examining coal-derived nanoparticles (NPs) containing potentially toxic elements (PTEs) confined in marine suspended sediments (MSSs) in port regions worldwide is an understudied topic, despite the fact that coal NPs have tremendous negative impacts on marine estuaries. The general objective of this study is to analyze the NP levels of coal, including PTEs, contained within MSSs in the general vicinity of the largest Caribbean port in Colombia. The morphology, size, chemical composition, and agglomeration states of NPs within MSSs of the sampled beaches were calculated through modern electron microscopy. The methodology used to detect chemical elements, unfortunately with EDS, it is not possible to precisely specify the chemical elements of low atomic weight (e.g. H, O, F, etc.) Therefore, with the EDS available today, it is only possible to have an idea of the chemical composition of each detected particle. Thus, it was possible to obtain the average frequency of the chemical elements identified in the 23 analyzed sampling points. Through the results, more than one thousand particles were detected in the most abundant phases, thus, the most frequent particles in the results of this manuscript were described. Sample point 8, located closest to the coal export port, had a higher concentration of nano-toxic elements (Al, Fe, Si, K, Mg, K) most concerning for human health in addition to being harmful to marine life. This study suggests that public policies dealing with MSS pollution need to be discussed by public managers to avoid further and sustained environmental degradation. The need to create projects will subsidize legacy liabilities generated by coal in seaports in other regions of the world.

Comprehensive Evaluation of Deep Coal Miners' Unsafe Behavior Based on HFACS-CM-SEM-SD

The unsafe behavior of miners seriously affects the safety of deep mining. A comprehensive evaluation of miners' unsafe behavior in deep coal mines can prevent coal mine accidents. This study combines HFACS-CM, SEM, and SD models to evaluate miners' unsafe behaviors in deep coal mining. First, the HFACS-CM model identifies the risk factors affecting miners' unsafe behavior in deep coal mines. Second, SEM was used to analyze the interaction between risk factors and miners' unsafe behavior. Finally, the SD model was used to simulate the sensitivity of each risk factor to miners' unsafe behavior to explore the best prevention and control strategies for unsafe behavior. The results showed that (1) environmental factors, organizational influence, unsafe supervision, and unsafe state of miners are the four main risk factors affecting the unsafe behavior of miners in deep coal mines. Among them, the unsafe state of miners is the most critical risk factor. (2) Environmental factors, organizational influence, unsafe supervision, and the unsafe state of miners have both direct and indirect impacts on unsafe behaviors, and their immediate effects are far more significant than their indirect influence. (3) Environmental factors, organizational influence, and unsafe supervision positively impact miners' unsafe behavior through the mediating effect of miners' unsafe states. (4) Mental state, physiological state, business abilities, resource management, and organizational climate were the top five risk factors affecting miners' unsafe behaviors. Taking measures to improve the adverse environmental factors, strengthening the organization's supervision and management, and improving the unsafe state of miners can effectively reduce the risk of miners' unsafe behavior in deep coal mines. This study provides a new idea and method for preventing and controlling the unsafe behavior of miners in deep coal mines.

Differences in the characteristics and pulmonary toxicity of nano- and micron-sized respirable coal dust

BACKGROUND

The characteristics of coal dust (CD) particles affect the inhalation of CD, which causes coal worker's pneumoconiosis (CWP). CD nanoparticles (CD-NPs, < 500 nm) and micron particles (CD-MPs, < 5 μm) are components of the respirable CD. However, the differences in physicochemical properties and pulmonary toxicity between CD-NPs and CD-MPs remain unclear.

METHODS

CD was analyzed by scanning electron microscopy, Malvern nanoparticle size potentiometer, energy dispersive spectroscopy, infrared spectroscopy, and electron paramagnetic resonance spectroscopy. CCK-8 assay, ELISA, transmission electron microscope, JC-1 staining, reactive oxygen species activity probe, calcium ion fluorescent probe, AO/EB staining, flow cytometry, and western blot were used to determine the differences between CD-NPs and CD-MPs on acute pulmonary toxicity. CCK-8, scratch healing and Transwell assay, hematoxylin-eosin and Masson staining, immunohistochemistry, immunofluorescence, and western blot were applied to examine the effects of CD-NPs and CD-MPs on pneumoconiosis.

RESULTS

Analysis of the size distribution of CD revealed that the samples had been size segregated. The carbon content of CD-NPs was greater than that of CD-MPs, and the oxygen, aluminum, and silicon contents were less. In in vitro experiments with A549 and BEAS-2B cells, CD-NPs, compared with CD-MPs, had more inflammatory vacuoles, release of pro-inflammatory cytokines (IL-6, IL-1β, TNFα) and profibrotic cytokines (CXCL2, TGFβ1), mitochondrial damage (reactive oxygen species and Ca2+ levels and decreased mitochondrial membrane potential), and cell death (apoptosis, pyroptosis, and necrosis). CD-NPs-induced fibrosis model cells had stronger proliferation, migration, and invasion than did CD-MPs. In in vivo experiments, lung coefficient, alveolar inflammation score, and lung tissue fibrosis score (mean: 1.1%, 1.33, 1.33) of CD-NPs were higher than those of CD-MPs (mean: 1.3%, 2.67, 2.67). CD-NPs accelerated the progression of pulmonary fibrosis by upregulating the expression of pro-fibrotic proteins and promoting epithelial-mesenchymal transition. The regulatory molecules involved were E-cadherin, N-cadherin, COL-1, COL-3, ZO-1, ZEB1, Slug, α-SMA, TGFβ1, and Vimentin.

CONCLUSIONS

Stimulation with CD-NPs resulted in more pronounced acute and chronic lung toxicity than did stimulation with CD-MPs. These effects included acute inflammatory response, mitochondrial damage, pyroptosis, and necrosis, and more pulmonary fibrosis induced by epithelial-mesenchymal transition.

The Impacts of Workplace Environment on Coal Miners’ Emotion and Cognition Depicted in a Mouse Model

Most coal mine accidents are caused by the unsafe behavior of employees. Previous studies have shown that there is a significant connection among the working environment, the psychological state of employees, and unsafe behaviors. However, the internal biological mechanism has not been revealed. To explore the physiological and psychological alterations of coal mine workers and the underlying mechanisms that cause unsafe behaviors, the current study established a novel coal mine environment biological simulation (CEBS) model in mice. This model recreated the underground workplace environment facts in coal mines such as temperature, humidity, and noise, and mice were employed to receive these conditioning stresses according to the 8-h work. Animal behavior tests were performed to evaluate the evolution of the mental state including anxiety and depression, as well as the abilities of learning and memory during the 4-week environmental simulation. CEBS mice showed the adaptation process of anxiety from occurrence to stability in the process of environmental simulation, and also suffered from severe depression compared to the control mice. In addition, impaired spatial memory was also implicated in mice after 4-week CEBS. The behavior results of CEBS mice were consistent with the previous psychological investigation of coal workers. In summary, a novel mouse model was established in this study to depict the occurrence of negative emotions and impaired cognition in coal miners by simulating the underground workplace environment, which provided a basis for further exploring the biological mechanism of miners’ unsafe behavior.