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Environmental Science and Pollution... May 2022To investigate the influence of dust produced by multi-dust sources at a fully mechanized mining face with a large mining height on the safety conditions in a coal mine,...
To investigate the influence of dust produced by multi-dust sources at a fully mechanized mining face with a large mining height on the safety conditions in a coal mine, the No. 22305 fully mechanized mining face of the Bulianta coal mine was considered as the research object in this study, and the space-time evolution of dust was analyzed with computational fluid dynamics (CFD). The wind flow simulation results show that the distribution law of wind flow is mainly affected by the structure of the roadway, and the speed and direction of the wind flow change greatly while passing by corners and through large-scale equipment. The dust generation and pollution diffusion laws with respect to time and space were investigated based on simulations of dust production due to 5-s, 30-s, and 60-s coal cutting, continuous coal cutting, and hydraulic support shifting. The space-time evolution law under different dust-producing times shows the transportation and diffusion procedure of dust under the wind flow; the dust-generated via coal mining and shifting were superposed on the downwind side and a 36-m-long dust belt was formed, which filled the coal mining space; the dust concentration in the breathing zone 120 m downwind the front drum had a dust concentration higher than 1700 mg/m, this was the crucial dust-proof area, and effective dust reduction methods should be addressed.
Topics: Coal; Coal Mining; Dust; Environmental Pollution; Wind
PubMed: 35028832
DOI: 10.1007/s11356-021-17967-5 -
The Science of the Total Environment Jun 2022Pesticides can be transported from the site of application to homes via different routes and lead to exposure of residents, raising concerns regarding health effects. We...
BACKGROUND
Pesticides can be transported from the site of application to homes via different routes and lead to exposure of residents, raising concerns regarding health effects. We built a deterministic model framework (OBOmod) to assess exposure of residents living near fields where pesticides are applied.
METHODS
OBOmod connects five independent models operating on an hourly timescale and high spatial resolution (meters). Models include descriptions of spray drift, volatilization, atmospheric transport and dispersion, exchange between outdoor and indoor air and exchange between indoor air and dust. Fourteen bulb field applications under different weather conditions and comprising 12 pesticides were simulated. Each simulation included the first seven days after the application. The concentrations computed with OBOmod were compared with those measured in outdoor and indoor air and the amounts measured in indoor dust samples.
RESULTS
Model evaluation indicated suitability of the developed framework to estimate outdoor and indoor air concentrations. For most pesticides, model accuracy was good. The framework explained about 30% to 95% of the temporal and spatial variability of air concentrations. For 20% of the simulations, the framework explained more than 35% of spatial variability of concentrations in dust. In general, OBOmod estimates remained within one order of magnitude from measured levels. Calculations showed that in addition to spray drift during application, volatilization from the field after spraying and pesticides in house dust are important routes for residents' exposure to pesticides.
CONCLUSIONS
Our framework covers many processes needed to calculate exposure of residents to pesticides. The evaluation phase shows that, with the exception of the dust model, the framework can be used in support of health and epidemiological studies, and can serve as a tool to support development of regulations and policy making regarding pesticide use.
Topics: Air Pollution, Indoor; Dust; Environmental Exposure; Pesticides; Volatilization
PubMed: 35151737
DOI: 10.1016/j.scitotenv.2022.153798 -
Environmental Science and Pollution... Apr 2023The recent increase in silicosis cases in several countries casts doubt on dust control practices and their effectiveness in preventing respirable crystalline silica... (Review)
Review
The recent increase in silicosis cases in several countries casts doubt on dust control practices and their effectiveness in preventing respirable crystalline silica (RCS) exposure. Apart from silicosis, RCS may lead to other illnesses, health-related quality of life losses for workers and their families, and economic losses for companies. Thus, this systematic literature review examined the effectiveness of interventions employed to prevent exposure to RCS and increase the use of dust control measures. The review used keywords related to dust control interventions to search seven databases. Search results were screened and extracted for synthesis. The narrative synthesis showed the extent of research investment in China. In several designs and combinations, the interventions utilized water, surfactant, foam, and air currents to reduce dust exposure. These interventions offer varying degrees of dust control effectiveness against RCS and respirable dust. Although evidence indicates that interventions significantly decrease dust concentration levels, the control measures in place may not effectively prevent workplace overexposure to RCS. The review found that education and training interventions are employed to improve dust controls and respiratory protective equipment (RPE) use. Also, marketing strategies promote the use of RPE. These interventions can increase the frequency of use of RPE and the adoption of best practice dust control measures. Interventions increase knowledge, awareness, and attitudes about RPE usage and generate positive perceptions while reducing misconceptions. However, the benefits obtained from an intervention may diminish after its implementation, indicating that the interventions may not continually motivate workers to adopt control measures or use RPE.
Topics: Humans; Dust; Air Pollutants, Occupational; Quality of Life; Silicon Dioxide; Inhalation Exposure; Occupational Exposure; Workplace; Silicosis
PubMed: 36964805
DOI: 10.1007/s11356-023-26321-w -
International Journal of Biological... Mar 2023Traditional polymer dust suppressants are limited due to environmental pollution, while polymer gels have attracted attention due to the advantages of environmental...
Traditional polymer dust suppressants are limited due to environmental pollution, while polymer gels have attracted attention due to the advantages of environmental protection and good biocompatibility. The purpose of this research is to prepare a new type of dust suppressant with a gel network structure, which was synthesized from soybean protein isolate and glycosylated with xanthan gum. The experimental results showed that the product obtained by reacting 0.2 % xanthan gum and 0.1 % soybean protein isolate at 90 °C for 4 h has the best binding effect on coal dust, and the coal husk hardness can reach 83 HA. The microscopic reaction and structure of the product were analyzed by infrared spectroscopy, X-ray diffractometer, and scanning electron microscope, and the results revealed the structural change and specific reaction process of the product. In addition, through molecular dynamics simulation, the dust suppression effect was confirmed and the mechanism of action between dust suppressant and coal was revealed. The performance test of the dust suppressant showed that its viscosity is 23.4 mPa·s, the contact angle at 1 s is 10.01°, the PM10 dust suppression efficiency can reach 98.10 %, the water retention is 44.44 % higher than that of water, and thermal stability is improved.
Topics: Dust; Polymers; Soybean Proteins; Coal; Gels; Water
PubMed: 36652985
DOI: 10.1016/j.ijbiomac.2023.123287 -
MMW Fortschritte Der Medizin Apr 2020
Review
Topics: Asthma; Child; Dust; Farms; Humans; Microbiota; Pulmonary Medicine
PubMed: 32248482
DOI: 10.1007/s15006-020-0329-7 -
Environmental Science and Pollution... Dec 2022Underground mines embroil several occupational hazards, including airborne dust generation from various mining operations. Line-of-sight remote Load Haul Dumper (LHD)...
Underground mines embroil several occupational hazards, including airborne dust generation from various mining operations. Line-of-sight remote Load Haul Dumper (LHD) mucking is adopted to draw the blasted muck from unsupported open stopes in underground metalliferous mines. Assessment of particulate matter (PM) concentrations and remote LHD operator's exposure is crucial for devising appropriate dust control measures. In this study, PM generated due to mucking in longhole open stope by line-of-sight remote LHD during downcast airflow was measured using real-time aerosol spectrometers. The particulate concentrations at upstream and downstream of dust source were analysed for various particle sizes as well as occupational dust types, such as alveolic and thoracic. The airborne dust concentration of ≤ 10 μm (PM), ≤ 5 μm, and ≤ 1 μm (PM) size at operator's location in downstream was measured 71.3%, 28.5%, and 3.0%, respectively. The alveolic and thoracic dust types, respectively, were determined 25.1% and 74.2% in downstream and 48.9% and 84.6% in upstream total airborne dust concentration (311 ± 246 μg/m). Dilution of airborne dust generated due to muck sliding inside the stope was analysed with time. Moreover, dust concentrations under typical airflow scenarios encountered in open stope were simulated using Ventsim software to identify the potential dust exposure hazard for remote LHD operator. The simulation revealed that downcast airflow causes maximum exposure of harmful airborne dust for remote LHD operator. This study enhanced the understanding of exposure potential of airborne dust during remote LHD mucking. Moreover, it emphasised adoption of tele-remote-operated LHD and automated mucking operation in open stopes.
Topics: Dust; Zinc; Lead; Mining; Occupational Exposure
PubMed: 35852746
DOI: 10.1007/s11356-022-22059-z -
Journal of Hazardous Materials Jan 2022Dusts generated during ferrochrome smelting in a pilot-scale DC arc furnace were sampled from the furnace freeboard and from the off-gas handling stream (cyclone and...
Dusts generated during ferrochrome smelting in a pilot-scale DC arc furnace were sampled from the furnace freeboard and from the off-gas handling stream (cyclone and baghouse). The dusts comprise fine-grained feed material (chromite, flux, and reductant); compositionally heterogeneous, glassy micro-spherules, interpreted as gas condensates and/or aerosolized melt droplets; and trace amounts of ferrochrome. Synchrotron-based micro-X-ray-fluorescence and micro-X-ray absorption near-edge structure around the chromium (Cr) K-edge was used to identify the distribution and speciation of Cr in dust particulates from the freeboard and the cyclone. The dust samples contain Cr in multiple oxidation states, including Cr(0) (hosted by ferrochrome), Cr(III), and Cr(VI). The majority of Cr occurs as Cr(III) in chromite. In both the furnace-freeboard and the cyclone dusts, Cr(VI) was consistently associated with the Si-Ca-Mg-rich micro-spherules. A major finding of this study is that Cr oxidation and Cr(VI) formation can occur in aerosolized dusts within the closed DC-arc furnace during ferrochrome smelting under conditions that are deemed to be essentially reducing. The association of Cr(VI) with the micro-spherules forwards the hypothesis that the high temperature of the furnace off-gasses and the flux composition influence the likelihood of Cr(VI) formation within a closed furnace under open-bath smelting conditions.
Topics: Chromium; Coal; Dust; Oxidation-Reduction; Synchrotrons
PubMed: 34418832
DOI: 10.1016/j.jhazmat.2021.126873 -
Environmental Microbiology Sep 2022In arid ecosystems, where the soil is directly exposed to the action of the wind due to sparse vegetation, dust aerosolization is a consequence of soil degradation and...
In arid ecosystems, where the soil is directly exposed to the action of the wind due to sparse vegetation, dust aerosolization is a consequence of soil degradation and concomitantly, a major vector of microbial dispersal. Disturbances such as livestock grazing or fire can exacerbate wind erosion and dust production. Here, we sampled surface soils in 29 locations across an arid landscape in southwestern USA and characterized their prokaryotic and fungal communities. At four of these locations, we also sampled potential fugitive dust. By comparing the composition of soil and dust samples, we determined the role of dust dispersal in structuring the biogeography of soil microorganisms across the landscape. For Bacteria/Archaea, we found dust associated taxa to have on average, higher regional occupancies compared to soil associated taxa. Complementarily, we found dust samples to harbour a higher amount of widely distributed taxa compared to soil samples. Overall, our study shows how dust dispersal plays a role in the spatial distribution of soil Bacteria/Archaea, but not soil Fungi, and might inform indicators of soil health and stability in arid ecosystems.
Topics: Archaea; Bacteria; Dust; Ecosystem; Soil; Soil Microbiology
PubMed: 35384241
DOI: 10.1111/1462-2920.15998 -
Environmental Science and Pollution... Mar 2023Tetrabromobisphenol A (TBBPA) and hexabromocyclododecane isomers (HBCDs) are widely detected in indoor environments, but the research on the accumulation, contamination,...
Tetrabromobisphenol A (TBBPA) and hexabromocyclododecane isomers (HBCDs) are widely detected in indoor environments, but the research on the accumulation, contamination, and human exposure of TBBPA and HBCDs in electronic products dust is still limited. It is unclear whether electronic products might pose human health risk via dust ingestion and dermal absorption. In this study, the levels and distributions of TBBPA and HBCDs were investigated in the personal computer (PC) interior dust and PC surface (upper and bottom) wipes. The median concentrations of TBBPA in PC interior dust, upper, and bottom surface wipes were 168.1 ng/g, 13.2 ng/m, and 15.2 ng/m, respectively. These levels were generally higher than those of HBCDs, which were 95.2 ng/g, 11.7 ng/m, and 12.3 ng/m, respectively. No significant correlations were found among the PC upper and bottom surface wipes, and interior dust, indicating different sources of TBBPA and HBCDs in PC interior and surface dust. The TBBPA and HBCDs in the PC interior dust were mainly released from inner PC materials, while the sources of target compounds on the surface wipes were likely from external environments. The exposure values of two occupational populations (including PC owners and PC repair workers) to TBBPA and HBCDs were measured by PC interior dust and upper surface wipes. The results imply dust ingestion (including hand-to-mouth uptake) is the main contributor of the exposure route to TBBPA and HBCDs for both PC owners and repair workers. Compared to PC owners, PC repair workers showed the greater risk in exposure assessment, which should be paid more attention.
Topics: Humans; Environmental Monitoring; Dust; Flame Retardants; Hydrocarbons, Brominated; Microcomputers
PubMed: 36692723
DOI: 10.1007/s11356-023-25497-5 -
Environmental Science & Technology May 2022Per- and polyfluoroalkyl substances (PFASs) were analyzed in outdoor ( = 101) and indoor dust ( = 43, 38 paired with outdoors) samples across mainland China. From 2013...
Per- and polyfluoroalkyl substances (PFASs) were analyzed in outdoor ( = 101) and indoor dust ( = 43, 38 paired with outdoors) samples across mainland China. From 2013 to 2017, the median concentration of ∑PFASs in outdoor dust tripled from 63 to 164 ng/g with an elevated contribution of trifluoroacetic acid and 6:2 fluorotelomer alcohol. In 2017, the indoor dust levels of ∑PFASs were in the range 185-913 ng/g, which were generally higher than the outdoor dust levels (105-321 ng/g). Emerging PFASs were found at high median levels of 5.7-97 ng/g in both indoor and outdoor dust samples. As first revealed by the total oxidized precursors assay, unknown perfluoroalkyl acid (PFAA)-precursors contributed 37-67 mol % to the PFAS profiles in indoor dust samples. A great proportion of C8 PFAA-precursors were precursors for perfluorooctanesulfonic acid, while C6 and C4 PFAA-precursors were mostly fluorotelomer based. Furthermore, daily perfluorooctanoic acid (PFOA) equivalent intakes of PFAAs (C4-C12) mixtures via indoor dust were first estimated at 1.3-1.5 ng/kg b.w./d for toddlers at high scenarios, which exceeds the derived daily threshold of 0.63 ng/kg b.w./d. from the European Food Safety Authority (EFSA). On this basis, an underestimation of 56%-69% likely remains without considering potential risks due to the biotransformation of unknown PFAA-precursors.
Topics: China; Dust; Environmental Monitoring; Fluorocarbons; Humans
PubMed: 33769795
DOI: 10.1021/acs.est.0c08242