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Aiming at the problems of complex environment and serious dust pollution in large open-pit coal yards, a dust suppression gel with a dual network structure was prepared by modifying the soluble starch and sodium alginate with iron ions. The changes of functional groups, thermal stability, and morphology structure before and after the reaction were analyzed by FTIR, TG-DSC, and SEM, and the formation mechanism of the dual network was revealed by XPS. Furthermore, the water absorption and water retention experiments proved that the dual network structure is more conducive to water retention than the single-layer network. According to molecular dynamics simulations and contact angle experiments, gel and adsorbed water molecules can approach coal dust molecules on their own to contact, wet, and combine with coal dust. The adhesion test proved that the dust suppression gel with iron ions had better adhesion to dust. The anti-freezing test shows that the dust suppression gel has good anti-freezing performance. The antifreeze test shows that the dust suppression gel still has excellent freeze-thaw resistance at the test temperature of  -20℃. The mechanical property test shows that the dust suppressant gel can prevent the product from being damaged by external force. The acid and alkali resistance experiments showed that the acid and alkali resistance of the gel was improved under the condition of iron ion modification, and the flying of coal powder was effectively prevented. This research provides a new theoretical idea for coal dust control in complex environment., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To obtain the adaptability range of the single-filter cartridge dust collector, a numerical analysis of the key component (filter cartridge) that affects the filter performance of the dust collector is carried out. The study found that the filtration air velocity gradually decreases from the top A to the bottom C of the filter cartridge surface. During the filtration process, along the surface of the filter cartridge from C to A, the pressure first drops and then rises. At C, the negative pressure is the largest, with an average of about 525 Pa. The ineffective filtration area of section A of the upper part of the filter cartridge accounts for 2/5 of the filtration area, and the concentration of the first layer of dust is y = (0.01 ± a) + 0.02 × (0.08 ± b) x exponentially decreasing. The critical particle size range that the filter cartridge can filter dust is M≥1.87 μm, and the best dust removal range of the dust collector is N≥4.625 μm. An agreement between experiment and simulating results proves the validity of simulation model and reliability of the experimental data. Enterprises can choose a reasonable dust removal method based on the research results to optimize the adaptability of the working environment and the dust collector. It also provides a theoretical basis for researchers to solve the problems in the filtration and cleaning process., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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., (© 2022 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Disposable diapers are now being used in incubators, raising questions concerning the amount of dust they produce during diaper change, and the subsequent effects on premature infants. This study compares the amount of dust produced during change of disposable diapers and during change of cloth diapers. The disposable diapers tested were Pampers (premature baby size, sterilized), manufactured by the Procter & Gamble Company. Cloth diapers tested included diaper covers. Results of the study indicated that disposable diapers produce far less dust than cloth diapers. Thus, disposable diapers can be satisfactorily used in incubators for premature infants. The difference in results between the two types of diapers might stem from their different structures: cloth diapers have a monolayer structure, whereas disposable diapers have a double cover over the refined pulp they contain, which might otherwise tend to generate dust.

High levels of lead in pavement dusts in parts of central London have been traced to newspaper printworks in the area. Concentrations exceeding 5000 micrograms g-1, the interim 'action level' adopted by the Greater London Council, extend up to 150 m from the works, with levels of greater than 200 000 micrograms g-1 encountered close to the exit of one works. By contrast, average levels alongside 14 major roads elsewhere in London ranged from 1360 to 3400 micrograms g-1. Identification of the printworks as the probable source was based on the spatial distribution of the lead-in-dust concentrations. Confirmation came from the close association between lead and tin concentrations, tin being a constituent of the lead alloy used in the printing industry. Such an association was not found in dusts contaminated by lead from petrol or paint. Tracking out on shoes and clothing, and possibly vehicles, is the most likely route by which the lead is leaving the works.

This paper presents an experimental study of the effect of the mass of dust retained on a fibrous filter bed operating singly and in a "cyclone-filter-bed" system on changes in filtration efficiency and accuracy, as well as the increase in flow resistance. The research was carried out using a novel and unprecedented method, determining the dust absorption coefficient km of the filter baffle under laboratory conditions. A filtration system built of a single cyclone and a cylindrical filter cartridge with an appropriately sized surface set behind it was studied. Conditions corresponding to the actual operating conditions of the air filter were maintained: dust concentration, filtration speed and dust extraction from the cyclone settling tank. The purpose of the research was to evaluate filter materials with different structures in terms of filtration efficiency and accuracy, as well as flow resistance. The study showed that the parameters of the structure of filter materials—permeability, grammage and thickness—affect the process of retaining dust particles. It was shown that the increase in the flow resistance of the filter bed has a higher intensity when dust grains of small sizes are directed at it, which is the case when the bed is operated behind a cyclone, which separates larger dust grains from the air. There is a reduction in the operating time of the filtration system due to the limitation of the permissible resistance ∆pfdop, and the corresponding dust absorption km has a lower value. For a fixed value of the flow resistance, the dust absorption coefficient km2 of three different filtration baffles AC, B2, and B, working with a cyclone, take values 50–100% smaller than when working in a single-stage system. It has been shown that the "cyclone-filter baffle" unit, due to its greater dust separation capability, allows the filter cartridge to operate for a longer time until a certain flow resistance is reached. This allows the unit to operate longer at lower flow resistance without changing the filter cartridge, thus saving energy. The km values obtained during the tests, using the proposed original method, allow the selection of the filter bed for specific vehicle operating conditions by modelling its course. [ABSTRACT FROM AUTHOR]

Waste generation is a part of every technological process, including galvanizing. The presented paper deals with the characterization of flue dust generated in the process of hot-dip galvanizing, and proposes possible methods for zinc recycling. The flue dust is released into the atmosphere as a white fume above the zinc bath, which is caused by the decomposition of ammonium chloride and zinc chloride present in the flux. This dust is classified as hazardous waste and is a material with a particle size below 90 µm. In addition to zinc and iron compounds, it contains water vapor and oils. The presented elemental, phase, and other characteristic methods of flue dust are important for the subsequent selection of a suitable method for processing the material. At present, this waste is not processed separately due to its low production, which is approximately 0.3 kg per 1 tonne of galvanized steel. The proposed hydrometallurgical recycling method enables the processing of flue dust on a small scale and enables the recovery of high-purity zinc in the form of metallic zinc or zinc oxide. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) and alternative bisphenols are widely used in the industrial production of polycarbonates and resin polymers. Adverse effects on human health have been described for BPA and owing to the structural similarity of alternative bisphenols and derivatives, a similar toxicity profile is expectable. Dust can act as a sink for bisphenols owing to the large surface area to mass ratio. Human risk exposure to bisphenols via indoor dust has been widely assessed in the last decade. The environmental conditions inside greenhouses, among other factors, facilitate that chemicals are released from greenhouse building materials to dust. This study aims to explore for the first time the potential of greenhouse dust as a new source of bisphenols for human exposure. For this purpose, a supramolecular solvent-based method was applied to the extraction of twenty-one bisphenols from greenhouse dust, prior to their determination by liquid chromatography-tandem mass spectrometry. Nineteen bisphenols were found in the five greenhouse dust samples analysed, with concentrations ranging from 5275 ng g -1 (BPA) to 0.25 ng g -1 (trichlorobisphenol A). The average daily dose (ADD) via dust ingestion for bisphenol compounds was calculated, in order to estimate the occupational exposure for inadvertent dust ingestion. Despite the calculated ADD value for BPA (47.81 ng kg -1  day -1 ) being below the tolerable daily intake proposed by EFSA (4·10 3  ng kg -1  day -1 ), this value was considerably higher than those previously reported for indoor dust, which brings to light the importance of considering greenhouse dust as bisphenols source of exposure for greenhouse workers., (© 2022. The Author(s).)

Road dust, which reflects ambient air quality, receives various pollutants including toxic metal(oid)s from several natural and/or anthropogenic sources. This manuscript reports a comprehensive evaluation of the levels of seventeen metal(oid)s in road dust of a megacity (Dhaka, Bangladesh). Different evaluation approaches were implemented including statistical analysis and GIS mapping, besides environmental, ecological, and human health risk indices. From 30 sampling sites, representative samples were collected, which were analyzed by neutron activation analysis. The average concentrations (± SD) of Na, Mg, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Zn, As, Rb, Sb, Cs, Ba, and W were 11,738 ± 560 µg g -1 , 12,410 ± 1249 µg g -1 , 62,127 ± 5937 µg g -1 , 8.89 ± 0.47 µg g -1 , 5224 ± 1244 µg g -1 , 66 ± 8 µg g -1 , 66.7 ± 6.9 µg g -1 , 547 ± 110 µg g -1 , 25,150 ± 1723 µg g -1 , 8.39 ± 0.65 µg g -1 , 125 ± 17 µg g -1 , 3.63 ± 0.56 µg g -1 , 87 ± 9 µg g -1 , 0.75 ± 0.28 µg g -1 , 4.40 ± 0.48 µg g -1 , 397 ± 87 µg g -1 , and 3.82 ± 1.77 µg g -1 , respectively. The distance-based redundancy analysis showed that the northern region was enriched with Na, Mn, Al, Fe, Zn, and Rb, while the southern region was enriched with Fe, Al, Ti, Cr, and Mg. The GIS mapping shows hot spots of Sc, Cr, Zn, and Cs were observed mostly in heavy traffic areas. Significant positive correlations of Fe-Sc, Al-Mg, V-Mg, V-Al, Cs-Rb, Cs-Sc, Rb-Sc, As-Na, and Cs-Rb invoked their inter-dependency and persistence in road dust. Depending on a set of environmental and ecological index-based calculation, the degree of metal(oid) pollution followed the descending order as W > Sb > Zn > Cr > As > Ti > Sc > V, while no pollution was recorded by Mn, Fe, Al, Rb, Cs, Co, and Ba. Importantly, the total hazard index values for adults and children were higher than unity, indicating potential non-carcinogenic health risks from exposure of road dust. Furthermore, the total carcinogenic risks from Cr and As through ingestion and dermal contact exceeded the standard guideline values. The implementation of different evaluation approaches strengthens the findings of metal(oid) source apportionment., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In order to reduce the dust pollution caused by the coal mining process, a novel composite environmental dust suppressant for coal dust control was synthesized by corn straw, sodium carboxymethyl cellulose (CMC), and additives. This study focused on the preparation conditions of the dust suppressant, and the performances of which were investigated systematically. Response surface method (RSM) was used to optimize the raw material formulation and preparation parameters. The optimum mass ratio of straw, CMC, and alkali of the dust suppression was 65:20:15 (m/m), which was prepared under the conditions of the reaction time being 1.5 h and the rotation speed being 300 r/min. The pH of the dust suppressant was 8.0, and the state of which was suspension. Additives were benefited to enhance the suppressant performance, and the surface tension and the contact angle could decrease to 32.4 mN/m and 32.0°. The suppressant has a maximum viscosity of 363.6 mPa·s, and the compressive strength could be up to 200 kPa. The hygroscopic rate could reach more than 4%. The wind erosion resistance could be up to 99 % at the wind speed of 14 m/s. After spraying the dust suppressant, the gap between particles was filled with dust suppressant, and the adjacent particles were bound by strong mechanical action., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Green plants can effectively retain atmospheric particle pollution and purify the air. As an important part of the campus ecosystem, they have a significant effect on absorbing atmospheric pollutants and improving the quality of the campus air environment. Six common greening plants were selected as the object in Xiangnan University. The dust retention capacity of plant leaves, leaf micro-structure, and leaf contact angle were measured. The results show that the highest amounts of dust removed by Osmanthus fragrans Lour was 3.451 g/m 2 , and the least amounts of dust removed by Magnolia denudata Desr . was 1.005 g/m 2 , and the maximum is 4.148 times of the minimum. The micro-structure of the plant leaf surface affects the amount of dust retention. The plant dust retention capacity with gully of the leaf surface and fluff, stomata, and sawtooth structure is relatively strong; The plant dust retention capacity with smooth, wax layer, leathery, and gully is relatively weak. The leaf contact area of a plant is related to its dust retention ability, that is, when the measured leaf contact angle is <90°, the leaf dust retention ability of the plant is strong. When the blade contact angle is >90°, the dust retention capacity is weak.

The article discusses the findings of a study to determine how laser affects historical paper documents. It notes that use of continuous wave laser radiation on a German geographic map that was printed in 1846 produced decreased discoloration after five years. Results of Fourier transform infrared (FTIR) spectroscopy concludes that laser radiation methods make it possible to remove thin layers of external pollutants such as dust, soot, and inks.

Dust emission is one of the critical problems of the mining industry. Dust emission can cause respiratory diseases among workers and adjacent residents of the factory and environmental pollution in the region. This study aims to reduce dust emissions of an iron ore concentrate plant in Iran. Applying dust control methods can affect the production process. Therefore, in this study, the value engineering (VE) method has been used, which focuses on improving the processes without affecting the main functions. This method is implemented in three stages. In the pre-study stage of VE, the prerequisites of study, such as determining the management requirements, study scope, evaluation criteria, forming the VE team, and planning, were met. In the study stage, the required information was collected; the studied process functions were identified and ranked; 62 ideas were created based on the functions and then evaluated; the final scenarios for the selected device, hopper, were developed and ranked using the VIKOR method; and finally, confirmation of the results by the management was obtained. In the post-study stage, the results will be implemented. The approach of this study was based on maintaining the functions of the production process and production rate and finding the most effective solution to reduce dust and environmental hazards, the most efficient solution in terms of performance, and the most cost-effective solution in terms of fixed and variable costs. According to the results, dry and wet dust suppression systems are the best options among the scenarios to meet the objectives of this study., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The article examines mortality among pulp and paper mill workers according to the mail mill pulping process, department, and gender. It states that death from acute myocardial infarction was increased, which was probably related to a combination of different occupational exposures such as dust, sulfur compounds, shift work and noise. It is concluded that the study supports earlier indications of fatal cardiovascular effects among pulp and paper mill workers.

The filter cartridge dust collector has been widely used in industry, but the influence of its internal structure on its operation effects is rarely studied. FLUENT software was used to simulate the influence of different air volume and permeability values on the gas-solid two-phase flow of dust removal characteristics for a filter cartridge. The results show that when the air volume of the fan was greater than 1600 m 3 /h, the increase in the dust reduction rate was not obvious, and the high-velocity airflow filled the entire dust removal chamber, which was conducive to the filter using the largest effective filtration area to remove dust; the optimal air volume was 1600 m 3 /h. Furthermore, the dust removal effect gradually became worse when the porosity was higher than 0.65, but the fluidity of the internal air was poor when it was lower than 0.65. The optimum porosity was 0.65. A simulated validation analysis was conducted using the above optimal parameters. As the proportion of particles below 2 μm increased, the dust removal effect worsened.

Chemical exposure via dust ingestion is of great interest to researchers and regulators because children are exposed to dust through their daily activities, and as a result, to the many chemicals contained within dust. Our goal was to develop a workflow to identify and rank organic chemicals that could be used as tracers to calculate children's dust ingestion rates. We proposed a set of criteria for a chemical to be considered a promising tracer. The best tracers must be (1) ubiquitous in dust, (2) unique to dust, (3) detectable as biomarkers in accessible biological samples, and (4) have available or obtainable ADME information for biomarker-based exposure reconstruction. To identify compounds meeting these four criteria, we developed a workflow that encompasses non-targeted analysis approaches, literature and database searching, and multimedia modeling. We then implemented an ad hoc grading system and ranked candidate chemicals based on fulfillment of our criteria (using one small, publicly available dataset to show proof of concept). Initially, five chemicals (1,3-diphenylguanidine, leucine, piperine, 6:2/8:2 fluorotelomer phosphate diester, 6:2 fluorotelomer phosphate diester) appeared to satisfy many of our criteria. However, a rigorous manual investigation raised many questions about the applicability of these chemicals as tracers. Based on the results of this initial pilot study, no individual compounds can be unequivocally considered suitable tracers for calculating dust ingestion rates. Future work must therefore consider larger datasets, generated from broader measurement studies and literature searches, as well as refinements to selection criteria, to identify robust and defensible tracer compounds.

Roadside dust can contain particulates enriched with potentially toxic elements (PTEs) as a result of the degradation of mechanical vehicular parts, tyre wear and combustion processes. To assess the potential accumulation of these metals in roadside areas, a snapshot study was carried out, investigating metal content at rural and urban locations in central Scotland. Samples of road dust were collected at six sites representing low, medium and high traffic intensity at rural and urban locations. The samples were separated based on particle size and analysed for heavy metal content using inductively coupled plasma optical emission spectroscopy (ICP-OES) after acid digestion. The metals analysed were aluminium (Al), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), lead (Pb) and zinc (Zn). The rural area measurements were carried out in West Lothian, approximately 13 to 17 miles west of the city of Edinburgh (UK). The urban area measurements were carried out in the southern part of the Edinburgh city district (UK). Concentrations of Cu, Cr and Zn were found to correlate with traffic intensity, although only Cu and Zn concentrations exceed recommended EC directive 86/278/EEC guidelines for urban runoff materials. The metal concentrations of small particles (0.45-20 μm) were exceedingly high in both Cu and Zn at areas of high traffic intensity, indicating potential areas of concern regarding health impacts for pedestrians and cyclists who are exposed to roadside dust on a regular basis.

Photovoltaic systems (PV) have been extensively used worldwide as a reliable and effective renewable energy resource due to their environmental and economic merits. However, PV systems are prone to several environmental and weather conditions that impact their performance. Amongst these conditions is dust accumulation, which has a significant adversative impact on the solar cells' performance, especially in hot and arid regions. This study provides a comprehensive review of 278 articles focused on the impact of dust on PV panels' performance along with other associated environmental factors, such as temperature, humidity, and wind speed. The review highlights the importance of modelling dust accumulation along with other ecological factors due to their interactive nature, and the differences between cleaning techniques and schedules effectiveness. Moreover, the study provides a review of statistical and artificial intelligence models used to predict PV performance and its prediction accuracies in terms of data size and complexity. Finally, the study draws attention to several research gaps that warrant further investigation. Among these gaps is the need for proper dynamic optimisation models for cleaning schedules and a more advanced machine and deep learning models to predict dust accumulation while considering environmental and ageing factors. [ABSTRACT FROM AUTHOR]

This research developed a more efficient integrated model (IM) based on combining the Nash-Sutcliffe efficiency coefficient (NSEC) and individual data mining (DM) algorithms for the spatial mapping of dust provenance in the Hamoun-e-Hirmand Basin, southeastern Iran. This region experiences severe wind erosion and includes the Sistan plain which is one of the most PM 2.5 -polluted regions in the world. Due to a prolonged drought over the last two decades, the frequency of dust storms in the study area is increasing remarkably. Herein, 14 factors controlling dust emissions (FCDEs) including soil characteristics, climatic variables, digital elevation map, normalized difference vegetation index, land use and geology were mapped. Correlation and collinearity among the FCDEs were examined by the Pearson test, tolerance coefficient (TC) and variance inflation factor (VIF), with the results suggesting a lack of collinearity between FCDEs. A tree-based genetic algorithm was applied to prioritize and quantify the importance weights of the FCDEs. Thirteen individual data mining models were applied for mapping dust provenance. The model performance was assessed using root mean square error, mean absolute error and NSEC. Based on clustering analysis, the 13 DM models were grouped into five clusters and then the cluster with the highest NSEC values used in an integrated modelling process. Based on the results, the IM (NSEC = 93%) outperformed the individual DM models (the NSEC values range between 51 and 92%). Using the IM, 11, 5, 7 and 77% of the total study area were classified into low, moderate, high and very high susceptibility classes for dust provenance, respectively. Overall, the results illustrate the benefits of an IM for mapping spatial variation in the susceptibility of catchment areas to act as dust sources.

The article presents a study investigating whether exposure to dust from absorbent hygiene products containing superabsorbent polymer is related to symptoms from the airways and from the eyes. The study also estimated the current exposure to superabsorbent polymer among production and maintenance workers in a plant involved in the production of hygiene products. The study revealed that workers manufacturing diapers in the hygiene industry have an increased prevalence of symptoms from the nose.

Abstract: Dust accumulation is one of the natural phenomena that adversely affects the performance of solar systems. Since 1942, many efforts have been made to address the severity of deposited particles like dust, water stains, carbon from smoke, pollen in agricultural regions, etc. on the efficiency reduction of solar devices, which results in additional costs either from oversizing the system or from cleaning it. Although various innovative methods have been employed to clean the surface of grimy PVs, a holistic approach needs to show the cleaning mechanism under different climate conditions. This review highlights the findings from several references in three time periods and focusing on their similarities. For scaling up the appropriate mitigation method, four different global zones are explored based on suspended particles in the air. Consequently, the pattern of dust distribution in different parts of the world is assessed and it was found that the Middle East and North Africa have the worst dust accumulation zones in the world. Finally, a set of recommendations and guidelines with regard to the different climatic zones and their characteristics are presented especially for the installers of PV or other solar devices to implement a suitable cleaning system. [Copyright &y& Elsevier]

In this work, a methodology for chemical speciation analysis of inorganic As and Sb in urban dust using slurry sampling and detection by fast sequential hydride generation atomic absorption spectrometry is proposed. Doehlert design and desirability function were used to find the optimum conditions for hydride generation (1.0 mol L -1 HCl and 0.9% m v -1 NaBH 4 ). The accuracy of the analytical method was evaluated by analysis of reference material fly ash (BCR 176R), addition and recovery tests for inorganic As species, and comparison of independent methods for Sb determination in urban dust samples. The determination of the total concentrations of As and Sb and their inorganic species presented good accuracy, between 80 ± 1 and 101 ± 6%. Precision was expressed as the relative standard deviation and was better than 4.7% (n = 3). The limit-of-quantification values were 0.23 and 1.03 mg kg -1 for As and Sb, respectively. The methodology was applied to eight samples of dust collected in an urban area of Salvador and Jaguaquara cities, Bahia, Northeast, Brazil, with an aerodynamic size lower than 38 μm. Concentrations of pentavalent inorganic species (iAs 5+ and iSb 5+ ) in relation to trivalent species (iAs 3+ and iSb 3+ ) were found in urban dust collected in the city of Salvador, which are regarded as more toxic for both elements. The enrichment factor and geoaccumulation index (I geo ) values showed that for some samples, the concentrations of iAs and iSb presented strong enrichment and, and regarding environment, strong to moderately polluted by iAs and iSb, with an indication of anthropogenic contributions. The occurrence of these inorganic constituents in the urban area of Salvador can be related with intense industrial activities and vehicular traffic.

Objective: Asian dust is a natural phenomenon in which dust particles are transported from desert areas in China and Mongolia to East Asia. Short-term exposure to Asian dust has been associated with cardiovascular disease through mechanisms such as systemic inflammation. Because inflammation is a potential trigger of placental abruption, exposure may also lead to abruption. We examined whether exposure to Asian dust was associated with abruption., Design: A bi-directional, time-stratified case-crossover design., Setting and Population: From the Japan Perinatal Registry Network database, we identified 3014 patients who delivered singleton births in hospitals in nine Japanese prefectures from 2009 to 2014 with a diagnosis of placental abruption., Methods: Asian dust levels were measured at Light Detection and Ranging monitoring stations, and these measurements were used to define the Asian dust days. As there was no information on the onset day of abruption, we assumed this day was the day before delivery (lag1)., Main Outcome Measures: Placental abruption., Results: During the study period, the Asian dust days ranged from 15 to 71 days, depending on the prefecture. The adjusted odds ratio of placental abruption associated with exposure to Asian dust was 1.4 (95% confidence interval = 1.0, 2.0) for cumulative lags of 1-2 days. Even after adjustment for co-pollutant exposures, this association did not change substantially., Conclusions: In this Japanese multi-area study, exposure to Asian dust was associated with an increased risk of placental abruption., Tweetable Abstract: Exposure to environmental factors such as Asian dust may be a trigger of placental abruption., (© 2019 Royal College of Obstetricians and Gynaecologists.)