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Respirable coal mine dust (RCMD) exposure is one of the utmost health hazards to the mining community causing various health issues, including coal worker pneumoconiosis (CWP). Considering multiple potential sources of RCMD having different physicochemical properties within the same mine suggests a wide range of health impacts that have not yet been studied extensively. In this work, we investigate the toxicity of lab-created RCMD based on different sources: coal seam, rock dust, host floor, and host roof collected from the same mine. Comparative samples obtained from several mines situated in various geographic locations were also assessed. This work quantifies metal leaching in simulated lung fluids and correlates dissolution with in vitro immune responses. Here, dissolution experiments were conducted using two simulated lung fluids; Gamble solution (GS) and artificial lysosomal fluid (ALF). In vitro studies were performed using a lung epithelial cell line (A549) to investigate their immune responses and cell viability. Si and Al are the most dissolved metals, among several other trace metals, such as Fe, Sr, Ba, Pb, etc. RCMD from the coal seam and the rock dust showed the least metal leaching, while the floor and roof samples dissolved the most. Results from in vitro studies showed a prominent effect on cell viability for floor and roof dust samples suggesting high toxicity. [ABSTRACT FROM AUTHOR]

The β-Lactam antibiotic amoxicillin is among the most widely used antibiotics in human and veterinary medicine. Consequently, amoxicillin is abundant in natural waters and can undergo diverse abiotic reactions to form degradation compounds under environmental conditions. Yet, little is known about these decay pathways and mineralogical impacts on environmental amoxicillin degradation. The current study focuses on understanding the mineralogical influences of amoxicillin degradation under ecological conditions. We studied the role of anatase and kaolinite on amoxicillin degradation under irradiated and non-irradiated conditions. Anatase increases amoxicillin degradation by 4.5-fold in the presence of light compared to just being exposed to sunlight. Interestingly, anatase also showed a higher degradation rate under dark than light controls. Conversely, kaolinite diminishes the amoxicillin degradation under irradiation. The formation of degradation compounds was mineralogy-controlled, while no mineralization was observed. Further, we irradiated amoxicillin with a high-intensity light to evaluate its removal from wastewater. The formation of varying amoxicillin degradation products with high-intensity light will limit its removal from wastewater. Our study emphasizes that the mineralogical impact on amoxicillin degradation is diverse, and the role of anatase is significant. Consequently, the increased addition of manufactured titanium nanoparticles to the environment can further enhance these effects. [ABSTRACT FROM AUTHOR]

Coal mine workers are continuously exposed to respirable coal mine dust (RCMD) in workplaces, causing severe lung diseases. RCMD characteristics and their relations with dust toxicity need further research to understand the adverse exposure effects to RCMD. The geographic clustering of coal workers' pneumoconiosis (CWP) suggests that RCMD in the Appalachian region may exhibit more toxicity than other geographic regions such as the Rocky Mountains. This study investigates the RCMD characteristics and toxicity based on geographic location. Dissolution experiments in simulated lung fluids (SLFs) and in vitro responses were conducted to determine the toxicity level of samples collected from five mines in the Rocky Mountains and Appalachian regions. Dust characteristics were investigated using Fourier-transform infrared spectroscopy, scanning electron microscopy, the BET method, total microwave digestion, X-ray diffraction, and X-ray photoelectron spectroscopy. Inductively coupled plasma mass spectrometry was conducted to determine the concentration of metals dissolved in the SLFs. Finer particle sizes and higher mineral and elemental contents were found in samples from the Appalachian regions. Si, Al, Fe, Cu, Sr, and Pb were found in dissolution experiments, but no trends were found indicating higher dissolutions in the Appalachian region. In vitro studies indicated a proinflammatory response in epithelial and macrophage cells, suggesting their possible participation in pneumoconiosis and lung diseases development. [ABSTRACT FROM AUTHOR]