Dust Particles Research Articles

Cancer Risks Associated with Chronic Exposure to Urban Dust May Increase in a Mining Town

ABSTRACT Mining generates adverse environmental effects, such as the dispersion of potentially toxic elements (PTEs) contained in mine tailing particles. This research estimated cancer risk and hazard quotient associated with PTEs contamination from urban dust in a mining town. The morphology and chemical composition of urban dust particles were analyzed. Pseudo-total, pulmonary, and gastric bioaccessible PTE concentrations were determined by wet digestion and extraction with Gamble (pH = 7) and 0.4 M glycine solutions (pH = 1.5). Cancer risk and hazard ratios in children and adults were calculated using risk equations. The irregular morphology of the dust, the particle size distribution (1–4 µm), and the As, Cd, and Pb concentrations indicate that the particles originate from mine tailings. Pseudo-total As (6 171 mg kg−1), Pb (2 394 mg kg−1), Cd (29 mg kg−1), and Zn (3 486 mg kg−1) were high. High bioaccessible gastric concentrations were observed for As (225 mg kg−1), Pb (257 mg kg−1), and Zn (269 mg kg−1). Just As and Pb pose a non-cancer disease risk in children and adults. Gastric bioaccessible As and Cd were higher in distant areas from tailing heaps. The cancer risk of As exceeded the maximum permissible value in children and adults. Control the dispersion of urban dust to avoid inhalation or ingestion is essential to get this goal five recommendations were included.

Phosphorus transitions driven by cyclone biparjoy linked middle east North Africa (MENA) and Indian Thar Desert dust storm pathways in Asia’s largest grassland

Phosphorus (P) is an important nutrient for terrestrial ecosystems like grassland and plays a critical role in influencing primary productivity and hence ecosystem dynamics. The deposition of airborne dust, particularly from arid and semiarid regions, has been recognised as a significant source of phosphorus input in distant ecosystems. The study area, the Banni grassland, is a semiarid ecosystem with a unique geological history that has experienced degradation for various natural and anthropogenic reasons. It is located in the arid tract of western India. Soil samples were collected from 10 × 10 km grid locations in the grassland before, 48 h after, and 20 days after a cyclonic storm, Biparjoy, which hit the region in June 2023. Statistical analyses (Shapiro‒Wilk normality and Kruskal–Wallis H test) were performed on the data to assess the differences in phosphorus concentrations in terms of PAC (Phosphorus Activation Coefficient) among the phases. To examine the long-range transport of dust-borne phosphorus and its subsequent deposition in the target grassland, we employed an interdisciplinary approach that integrated satellite imagery and ground-based measurements. Spatial and temporal variations in dust emissions were assessed using satellite remote sensing data, while ground truthing was performed for phosphorus content analysis using standard protocols. The aerosol data from MERRA-2 for the past 40 years were used to examine the relationships between aerosol concentrations and wind direction and speed. Our findings revealed that the Middle East, North Africa, and Thar Desert significantly contributed to phosphorus deposition in the target grassland during specific seasons. The SW cyclone ‘Biparjoy’, which followed the same track of aerosol loading (MENA), made landfall in this zone (June 16, 2023) and affected the P depositional patterns. The pre-cyclone, post-cyclone and 20 DAC (days after cyclone) had AP values of 15.15, 22.54 and 24.06, respectively. However, the TP values were 45.81 ± SE = 1.73, 60.95 ± SE = 1.39 and 61.98 ± SE = 1.40, respectively. The highest TP values were in phase 3 (20 DAC phase) (61.89 ± SE = 1.40). Similarly, the transformation of locked forms of P to bioavailable forms was coincidental with higher PSM (Phosphate Solubilising Microorganisms) in soil samples. Dust storms and other atmospheric circulation patterns were found to play pivotal roles in facilitating the long-range transport of phosphorus-laden dust particles from these source regions to the target grassland. Ultimately, our research contributes to the broader understanding of global nutrient cycling and land‒air interactions, enabling informed decision-making for the conservation and sustainable management of terrestrial ecosystems.

Drastic effects of N2 addition in the chemical composition of C2H2/Ar glow discharges

Abstract The effects of nitrogen on the physicochemical properties of cold acetylene plasmas have been experimentally studied in C2H2/Ar capacitive RF discharges. Two discharges containing respectively 0.8% and 6.3% N2 in the initial gas mixture were investigated under conditions of incipient polymerization, using mass spectrometry, light scattering, and optical emission spectroscopy. During the initial transient, dust particles, small polyynes, and C2 radicals were found to form and decay in parallel with a steep drop in the C2H2 concentration and an increase in the concentration of HCN, which was more prominent for the 6.3 % N2 mixture, and participated actively in the plasma chemistry. Over this time interval, relevant plasma parameters including the electron density and excitation temperature, the self-bias voltage, and the density of electronic excited states of various plasma species were found to undergo sharp variations. After this initial transient, lasting for about 20 s, a steady state was reached with stable plasma properties. Ion distributions were measured in the steady state, where no dust particles remained. The distributions of positive ions were dominated by species with an even number of carbon atoms, reflecting the prevailing polymerization mechanisms. The increase in the N2 concentration from 0.8% to 6.3% led to a decrease in the global cation signal and to a marked growth in the intensity of detected anions. The cation distributions did not change much, but in the anion distributions, the peaks corresponding to the masses of the C2n-1N- (n= 1-4) ions grew by orders of magnitude, in contrast with those of the adjacent C2nH-peaks, which showed comparatively modest changes. These results could help identify anionic polymerization routes. Note that the two anion families mentioned correspond to the negative ions observed thus far in interstellar and circumstellar media.

Changes in dust concentration in a gas-dust cloud during blasting in an iron ore pit

In open-pit extraction of minerals emit large amounts of harmful dust fractions and gas into the atmosphere. This leads to atmospheric pollution in open pit and sanitary protection zones. The largest dust emissions are observed during blasting operations in open pits. This is especially the cases when unfavorable meteorological conditions occur, means of dust sup-pression are not sufficiently effective, blasting technology was violated. Dust particles are known to be able to propagate long distances from the source of the explosion. Dust fractions up to 10 µm diameter are the most dangerous, as they are the main risk factor for the devel-opment of chronic respiratory diseases. In particular, according to European standards, the average daily concentration of dust particles with a diameter between 2.5 and 10 µm should not exceed 0.05 mg/m3. The paper estimates mass concentrations of dust fractions in the gas-dust cloud at the dynamic stage of its formation after a mass explosion in an iron ore open pit. The following assumptions were made in the calculations: no influence of the temperature factor (ejected air flows); dust particles are spherical; flow of dust fractions by the gas flow follows the Stokes law. The ranges of variation of ascent height and mass concentrations of dust fractions at the dynamic stage of gas-dust cloud formation are established. In particular, the lift height of the dust fraction is directly proportional to the value of the dynamic impulse. The differ-ence in mass concentrations of dust fractions in the gas-dust cloud is due to the physical and mechanical properties of rocks destroyed by boreholes explosive substance charge. When de-termining the mass concentrations of dust fractions, the results of experimental studies were used, which were carried out in the open pit of Ingulec Mining and Processing Combine. The graphical dependence of average mass concentrations of dust fractions depending on the height of their ascent at the dynamic stage of gas-dust cloud formation is presented, the re-gression equation in the form of a degree function is obtained. The results of calculations have shown that the greatest intensity of mass concentration increase in the gas-dust cloud at the dynamic stage of its formation is characteristic of dust fractions with diameter up to 31 μm. The intensity of growth of mass concentrations of larger dust fractions decreases markedly.

Study on the preparation and mechanism of environmentally friendly polysaccharide-xanthan gum gel dust suppressants.

In response to the dust pollution problem in open-pit mines, an environmentally friendly network structure with a dust suppressor structure was prepared by grafting acrylamide (AM) monomers onto xanthan gum (XG). The results show that the polymer produced from 1g XG, 15g AM, and 0.45g trimethylolpropane triglycidyl ether (TTE) had a more orderly structured gel with a viscosity of 81.08mPa·s and a crust thickness of 3.3mm. The structure of the product was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TG-DSC), confirming the success of the graft copolymerization reaction. Scanning electron microscopy (SEM) revealed a uniform and dense protective layer on the dust surface, indicating that the dust suppressor effectively penetrated and filled the gaps between dust particles, causing particle aggregation. The dust suppressor had a dust erosion rate of only 24.12% at a wind speed of 9m/s. The hydroxyl groups of XG, the amino groups of AM, and the vinyl groups of TTE crosslink to form a network structure, optimizing the adhesion, filling, and aggregation effects between dust particles. The dust suppressors studied here have good wetting, moisturizing, and degradable properties, which can provide significant economic and socioenvironmental benefits to the field of dust control.

Existence of hydroxymethanesulfonate (HMS) during spring haze and sandstorm events in Beijing: Implications for a heterogeneous formation pathway on mineral aerosols.

Hydroxymethylsulfonate (HMS) is an abundant secondary organic aerosol from aqueous or heterogeneous processes and may be misidentified as sulfate in conventional measurements. High concentrations of HMS have been observed in humid winter and autumn haze in northern China, while its prevalence in other seasons is unclear and the production medium is controversial. In this study, our field measurements in Beijing during the 2021 spring first showed the presence of HMS in PM2.5 during both haze and sandstorm events despite the different atmospheric conditions. HMS accounted for 0.44% of PM2.5 during haze periods, higher than the proportion (0.097%) during sandstorms. The sum of HMS and sulfate was also higher during the haze (6.5μgm-3) than during the sandstorm (2.6μgm-3), while the HMS/sulfate molar ratio during the haze (0.021) was similar to the value during the sandstorm (0.019). HMS concentration showed a good positive correlation with aerosol water content (AWC), indicating multiphase production. During haze periods, relatively high AWC favored the formation of HMS. In contrast, relative humidity and AWC decreased significantly during sandstorm events, while high pH favored HMS formation. In addition, higher concentrations and proportions of HMS were observed in PM2.5-10 than in PM2.5. The presence of HMS in dust particles indicated a heterogeneous formation mechanism of HMS on mineral aerosols. Our findings broaden the prevalence of HMS in aerosols and indicate a new HMS formation mechanism from the perspective of observation.

Seasonal Variations in the Strength of Sporadic Meteor Sources Observed by Meteor Radar

AbstractSporadic meteors are a significant source of metals in the Earth's atmosphere and ionosphere, and the understanding of the seasonal variations of their strengths can provide valuable insights into the origins and orbits of cosmic dust particles near Earth. This study analyzes meteor echo data collected by an all‐sky interferometric meteor radar in Ledong (LD, 18.4°N, 109.0°E) to quantify the strengths of sporadic meteor sources and their seasonal variations. The results indicate that the helion, antihelion, and apex sources are stronger than the north toroidal source, highlighting a concentration of sporadic meteors near the ecliptic plane and fewer near the ecliptic poles. Distinct seasonal variations are observed, with meteor activity peaking in April and September, likely corresponding to periods of increased meteor and dust particle density in Earth's orbit. Moreover, eight meteor showers are identified as significantly influencing the apparent radiant distributions and have comparable strengths with sporadic meteor sources. To enhance the analysis, a monthly radiant weighting system in ecliptic coordinates is developed, enabling precise calculation of source strengths and improved characterization of seasonal variations in radiant distributions. This research advances our understanding of sporadic meteors and their role in Earth's atmospheric processes, providing a foundation for future investigations into cosmic dust dynamics.

Short-term exposure to desert dust and sandstorms and all-cause and cause-specific mortality and morbidity: A systematic review and meta-analysis.

Desert dust and sandstorms raise concerns about their adverse effects on human health. Over the last decade, special attention has been given to mineral dust particles from desert sand. However, evidence from previous literature reviews has yielded inconclusive results regarding their health effects. We aim to systematically synthesize evidence on the short-term health effects of desert dust exposure from major dust source areas. The bibliographic search was conducted using the MEDLINE (PubMed), Scopus, and Web of Science databases to investigate the health effects of short-term exposure to desert dust in human populations, using time series or case-crossover study designs. Study selection and reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We evaluated the risk of bias (RoB) for individual studies and the certainty of evidence (CoE) for environmental exposures, as developed by a group of experts convened by the World Health Organization (WHO). Publication bias was examined using funnel plots and Begg's asymmetry test. A total of 71 studies were included in the review, covering data from 1993 to 2024. Most studies focused on Asian and African desert dust, with fewer studies from Arabian, American, and Australian regions. We found a significant increase in the risk for all-cause mortality (Relative Risk, RR=1.0121, 95%CI=[1.0045, 1.0199]). In addition, the mortality risk associated with particulate matter less than 10μm (PM10) was slightly higher on dust days compared to non-dust days, while for particulate matter less than 2.5μm (PM2.5), the risk was higher on non-dust days. We also observed a significant increase in the risk for cardiovascular mortality (RR=1.0252, 95% CI=[1.0100, 1.0407]) during dust days compared to non-dust days, but not for respiratory mortality (RR=1.0001, 95% CI=[0.9773, 1.0277]). The risk also increased for cardiovascular (RR=1.0094, 95% CI=[1.0014, 1.0174]) and respiratory morbidity (RR=1.0693, 95% CI=[1.0188, 1.1224]). Exposure to desert dust and sandstorms is linked to increased risks of all-cause and cardiovascular mortality, as well as respiratory morbidity. The overall evidence quality for each exposure-outcome combination was assessed as moderate, although data limitations prevent the establishment of specific air quality thresholds for desert dust particles. This review highlights the need for targeted public health interventions in affected regions.

Metals and metalloids pollution levels, partitioning, and sources in the environmental compartments of a small urban catchment in Moscow megacity.

This study examines the contamination levels and sources of 32 metals and metalloids (MMs) in environmental compartments (roadside soil, road dust, and river suspended sediments) of a small urbanized river catchment located in Moscow megacity. MMs partitioning between particle size fractions (PM1000, PM1-10, and PM1) was analyzed by ICP-MS and ICP-AES methods. The pollution level of particle size fractions with MMs decreases in the following series: road dust>suspended sediments>soils. Absolute principal component analysis with multiple linear regression (PCA/APCS-MLR) shows that in both relatively coarse (PM1-10) and fine (PM1) fractions, traffic emissions are the primary contributors to pollution, whereas natural sources are dominant providers of chemical elements in bulk samples (PM1000). The predominance of fractions with a diameter over 10μm in all three studied compartments indicates that the mineral matrix of all compartments is formed predominantly by natural material. Across all compartments and their fractions, Sb, Cd, Zn, Mo, W, Sn, Cu, Pb, and Bi are consistently accumulated. PM1 and PM1-10 particles of road dust and suspended sediments also absorb Ni and Cr, suspended sediments retain Mn and As, and soils additionally accumulate As. Anthropogenic influence is more pronounced in PM1 and PM1-10 particles compared to bulk samples due to a large impact of industrial sources, traffic, construction activities, and waste storage. Polluted soils are an additional source of MMs to PM1 and PM1-10 of road dust and PM1-10 of suspended sediments, and road dust acts as a source of MMs to PM1-10 of soils.

African Dust Particles over the Western Caribbean: Chemical Characterization

African Dust Particles over the Western Caribbean: Chemical Characterization

Explore the key factors of fine dust particle migration during tunnel construction

Explore the key factors of fine dust particle migration during tunnel construction

Surface Energy of Insoluble Organic Matter Simulant: Evaluation Based on Adhesive Force Measured by Centrifugal and Impact Separation Methods

Abstract In protoplanetary disks, organic mantle is regarded as promoting the collisional sticking of rocky dust grains. However, the surface energy, which is one of the primary factors determining collisional sticking, has not been well quantified. Here, we evaluated it by measuring the adhesive forces of synthetic insoluble organic matter, which is a realistic, chemically synthesized simulant of the organic matter found in meteorites, comets, and interplanetary dust particles. The simulant was prepared by repeated decantation of the reaction products of small reactive molecules, which are observed abundantly in protoplanetary disks. The adhesive force was measured at room temperature using both centrifugal and impact separation methods. For the latter, we developed a new apparatus that may enable measurements under varied conditions in the future as the organic matter is sensitive to temperature. We demonstrated that the measurements obtained with the new apparatus worked well as they closely matched those obtained using the centrifugal method. The measurements show that the surface energy of the simulant is ∼10 mJ m−2, which is comparable to or even lower than that of silica, depending on disk conditions. Therefore, assuming that the simulant is similar to protoplanetary organic matter, the surface energy of the organic matter would not promote the collisional sticking of rocky dust grains. Other factors, such as the viscosity of organic matter, the role of water-soluble organic matter, and the environmental conditions in protoplanetary disks, may help us better assess the true effects of organic matter on collisional sticking.

Thermoelastoplastic contact and charge characteristics of nonrotationally symmetric lunar dust particles

Thermoelastoplastic contact and charge characteristics of nonrotationally symmetric lunar dust particles

Force fields for molecular dynamics simulations of charged dust particles with finite size in complex plasmas

Force fields for molecular dynamics simulations of charged dust particles with finite size in complex plasmas

Unveiling the P-solubilizing potential of bacteria enriched from natural colonies of Red Sea Trichodesmium spp.

Phosphorus (P) is pivotal for all organisms, yet its availability is, particularly in the marine habitat, limited. Natural, puff-shaped colonies of Trichodesmium, a genus of diazotrophic cyanobacteria abundant in the Red Sea, have been demonstrated to capture and centre dust particles. While this particle mining strategy is considered to help evade nutrient limitation, details behind the mechanism remain elusive. This study explores P-solubilizing bacteria (PSB) residing within Trichodesmium's associated microbial community, their potential contribution to the host, and the possible implications for P cycling in marine ecosystems. Bacterial enrichment on YBCII medium resulted in 28 enrichment cultures, primarily comprising bacterial families such as Rhodobacteraceae, Alteromonadaceae and Burkholderiaceae. Five enrichment cultures were further grown on hydroxyapatite, revealing their ability to consume and release Nitrogen and P while forming strong physical interactions with the mineral. A drop in pH was observed, indicating acid production as the primary P-solubilizing pathway. Co-cultivation experiments confirmed a positive effect on Trichodesmium erythraeum strain IMS101 growth by the presence of putative PSBs. These results reveal that the enriched bacteria exhibit significant P-solubilizing activity, thus potentially increasing the bioavailability of P in seawater. Thus, PSB could play a vital role in maintaining the P balance in the Red Sea, supporting the growth of Trichodesmium spp. and other marine organisms. Overall, our results contribute to a deeper understanding of the P cycle in the Red Sea and have implications for developing novel strategies for P management in marine ecosystems.

Climate response to stratospheric aerosol injection during the Harmattan season in West Africa

Abstract Stratospheric Aerosol Injection (SAI), a proposed climate intervention, aims to reduce the amount of solar radiation reaching the Earth's surface by increasing the reflectivity of the atmosphere, thereby offsetting the warming effect of greenhouse gases. During the Harmattan season (December-February) in West Africa, a natural meteorological phenomenon injects dust and sand particles into the atmosphere, leading to a cooling effect. In this study, we investigate the influence of SAI on West African surface temperature, dust, and other meteorological variables using the Whole Atmosphere Community Climate Model (WACCM) under the Shared Socioeconomic Pathway 2-4.5 (SSP2-4.5) scenario and the Assessing Responses and Impacts of Solar Climate Intervention on the Earth system with Stratospheric Aerosol Injection (ARISE-SAI) dataset. Our findings indicate that SAI intervention significantly impacts the projected surface temperatures, specific humidity, and wind speed changes during the Harmattan season. Compared to a future without SAI, the intervention shows a significant net cooling effect over most parts of West Africa during the mid-future period (2050-2069). Also, SAI intervention significantly decreases moisture content over southern and northern West Africa in the near-future (2035-2054), mainly due to the net cooling effects over West Africa, when compared to a future without SAI. This feature is enhanced in the mid-future period. The cooling effects of SAI are likely to reduce the air's capacity to hold moisture, leading to lower specific humidity levels relative to a future without SAI. It could also have negative implications, such as increased aridity compared to a future without SAI in the northern and central regions of West Africa. These findings also highlight the potential for SAI to improve air quality in certain areas but also underscore the need for careful consideration of implementation strategies and possible trade-offs. The changes from SAI observed are specific to the ARISE simulation and may differ from other SAI simulations.

Effect of combined Kappa-Cairns distributed electrons on modulational instability and envelope soliton of ion-acoustic waves in electron-ion dusty plasma

Abstract Theoretical and numerical investigations are performed to study the amplitude modulation of ion-acoustic waves in an unmagnetized collisionless dusty plasma system whose components are warm ions (adiabatic), charged (negative) dust particles and Combined Kappa-Cairns distributed electrons. Modulational instability of ion-acoustic waves is analyzed through derivation of the nonlinear Schrödinger equation using the reductive perturbation technique by implementing hydrodynamic equations for this system. The conditions for modulational instability for this electron-ion dusty plasma system have been developed, and the impacts of the relevant physical parameters on the instability region along with the maximum growth rate of instability are demonstrated. Bright and dark envelope solitons are presented, and it is observed that the profiles of envelope solitons are significantly influenced by the existence of high-energy Combined Kappa-Cairns distributed electrons.

Silicosis: from pathogenesis to therapeutics

Silicosis is an important occupational lung disease caused by exposure to respirable crystalline silica dust particles, with the clinical manifestations from asymptomatic forms to respiratory failure. The main pathological process involves parenchymal lung injury, inflammation and lung tissue fibrosis, but the exact pathogenesis remains elusive. Until now, there have been no effective treatments for silicosis due to the complexity of pathogenesis and irreversibility of pulmonary fibrosis. In this review we attempt to summarize the advances in pathogenesis and treatment of silicosis and to explore the current understanding of the molecular mechanisms involving in the initiation and development of silicosis and potential therapeutic targets.

Analysis on the dust prevention mechanism of air curtain in fully mechanized excavation tunnel

Aiming at reducing the dust pollution during the tunneling process and improving the application efficiency of air curtain dust prevention technology, according to the changes of radial jet velocity (vr), axial extraction velocity (ve) and extraction distance (L) in the formation process of air curtain, the numerical simulation method was used to analyze the rules of airflow structure evolution and the diffusion characteristics of dust particles in fully mechanized excavation tunnel. The results indicate that as vr and ve increase, the migration path of the wall jet of the air curtain changes into an axial direction; as L decreases, the migration distance increases accordingly. These phenomena make the airflow distribution in the working face tends to be uniform. The dust diffusion distance reduces as well, wherein, the range of the discrete area of dust particles decreases sharply, until all dust particles are concentrated in the accumulation area. On this basis, the vr, ve and L were optimized and applied in the 63up08 fully mechanized working face. By the application of the optimal parameters, the average dust removal efficiency at the driver’s position increased by 71%. The dust concentration was reduced and the working environment had been improved effectively.

The Gaussian-Drude Lens: A Dusty Plasma Model Applicable to Observations Across the Electromagnetic Spectrum

When radiation from a background source passes through a cloud of cold plasma, diverging lensing occurs if the source and observer are well-aligned. Unlike gravitational lensing, plasma lensing is dispersive, increasing in strength with wavelength. The Drude model is a generalization of cold plasma, including absorbing dielectric dust described by a complex index of refraction. The Drude lens is only dispersive for wavelengths shorter than the dust characteristic scale (λ≪λd). At sufficient photon energy, the dust particles act like refractive clouds. For longer wavelengths λ≫λd, the optical properties of the Drude lens are constant, unique behavior compared to the predictions of the cold plasma lens. Thus, cold plasma lenses can be distinguished from Drude lenses using multi-band observations. The Drude medium extends the applicability of all previous tools, from gravitational and plasma lensing, to describe scattering phenomena in the X-ray regime.