Dust Loading Research Articles

Selection of tropical trees and shrubs for urban greening in coal mine complex: a case study of Singrauli, Madhya Pradesh.

An experimental investigation was conducted to determine the effectiveness of roadside trees for removing dust and the effects of dust load on the physiology and micromorphology of the foliage. The present study was conducted near an open coal mining complex situated in Singrauli, Madhya Pradesh, India, to assess the air pollution tolerance index (APTI), anticipated performance index (API), dust capturing capacity (DCC), and leaf morphology of trees and shrubs growing around the coal fields. Results showed that Azadirachta indica, Mangifera indica, Ficus religiosa, Ailanthus excelsa, and Ficus benghalensis were the most tolerant species towards air pollution (high APTI scores), while plants like Calotropis gigantea, Lantana camara, and Tectona grandis were proven to be bio-indicator species. Butea monosperma, Ficus benghalensis, Alstonia scholaris, and Terminalia arjuna were plant species with the highest DCC. Two-way ANOVA showed significant differences site-wise and season-wise in the biochemical parameters of APTI and a considerable difference site-wise with respect to dust capturing capacity. Correlation and regression analyses revealed a very high positive correlation between APTI and ascorbic acid value. The study recommends suitable plant species to manage rising air pollution in the coal mine and nearby areas apart from suggesting the development of a green belt.

The Relationship Between the Saharan Air Layer, Convective Environmental Conditions, and Precipitation in Puerto Rico

AbstractThe Saharan Air Layer (SAL) is a hot, dry, and dust‐laden feature that advects large concentrations of dust across the Atlantic annually to destination regions in the Americas and Caribbean. However, recent work has suggested the SAL may be a contributing factor to high‐impact drought in the Caribbean basin. While the SAL's characteristic dust loadings have been the focus of much previous research, fewer efforts have holistically engaged the co‐evolution of the dust plume, its associated convective environment, and resultant rainfall in Caribbean islands. This study employs a self‐organizing map (SOM) classification to identify the common trans‐Atlantic dust transport typologies associated with the SAL during June and July 1981–2020. Using the column‐integrated dust flux, termed integrated dust transport (IDT), from MERRA‐2 reanalysis as a SAL proxy, the SOM resolved two common patterns which resembled trans‐Atlantic SAL outbreaks. During these events, the convective environment associated with the SAL, as inferred by the Gálvez‐Davison Index, becomes less conducive to precipitation as the SAL migrates further away from the west African coast. Simultaneously, days with IDT patterns grouped to the SAL outbreak typologies demonstrate island‐wide negative precipitation anomalies in Puerto Rico. The SOM's most distinctive SAL outbreak pattern has experienced a statistically significant increase during the 40‐year study period, becoming roughly 10% more frequent over that time. These results are relevant for both climate scientists and water managers wishing to better anticipate Caribbean droughts on both the long and short terms.

Monitoring of dust load level in Uman city

Monitoring of dust load level in Uman city

Possible impact of North Atlantic sea surface temperature on decadal variability of dust activity in Gobi Desert

Semiarid to arid regions located in north of China are known as one of the largest sources of dust aerosols in the globe. Previous studies demonstrated direct and indirect effects of atmospheric dust loading on climate. The surface and meteorological properties are known to be affecting dust entrainment process. In this study, we found decadal variations of dust occurrence in Gobi Desert with the period of ∼24 years, utilizing the data acquired at the surface meteorological stations. An analysis of reanalysis datasets shows significant correlations between February North Atlantic Sea Surface Temperature (NASST) and precipitation in Gobi Desert and Mongolia in the following summer, causing a decadal variation of dust event frequency in the subsequent spring over the region. Strong time-lagged correlation is shown to be linked to an atmospheric wave train pattern that initiated from the NASST region, affecting large-scale circulation, ultimately causing surface drought over Gobi Desert.

Implementation of mineralogy in COSMO5.05–MUSCAT and model dust loading comparison with measurements

Implementation of mineralogy in COSMO5.05–MUSCAT and model dust loading comparison with measurements

Priority directions for preserving the health of underground coal mining workers

Introduction. An increase in life expectancy, a decrease in the mortality rate of the working-age population and an extension of working longevity are the most important components in the development of the human potential of the Russian Federation. We observe the most unfavorable situation with the achievement of the above-mentioned targets in coal mining.
 The study aims to substantiate the priority directions for preserving the health of workers engaged in underground coal mining in modern production conditions based on an assessment of occupational risks to prolong their working longevity.
 Materials and methods. The authors have carried out the analysis of official statistics data (state reports of Rospotrebnadzor and the annual report of Rosstat) for 2021–2022 on the state of working conditions and occupational morbidity in the coal industry. We have summarized the materials of Rosugleprof for 2006–2022 on occupational morbidity in coal industry organizations. We have presented the data of epidemiological studies in a cohort of coal miners on the example of the Rostov region.
 Results. The authors note the largest proportion of cases of occupational pathology among employees of mining enterprises — 40.3%. The most at risk are: sinkers (10.2% of all newly identified cases of occupational diseases in 2022), miners of the treatment face (6.5%), excavator drivers (4.5%). In the structure of occupational morbidity of miners, the leading place is occupied by radiculopathy — 27.0%; sensorineural hearing loss — 22.9%; vibration disease — 22.0%; respiratory diseases (occupational bronchitis, pneumoconiosis, COPD) — more than 15.5%. In a cohort of miners with an established diagnosis of occupational diseases, it was shown that the standardized relative risk (SRR) of death from diseases of the circulatory system was 1.55 times significantly higher compared with the control population.
 Mortality from malignant neoplasms in miners was 44% higher than mortality in the population (SRR=1.44). At the same time, the death rate from the subclass malignant neoplasms of the respiratory system was 2.02 (95% CI 1.85–2.20), and from malignant neoplasms of the bronchi and lungs 2.24 (95% CI 2.04–2.46). The risk of death from respiratory diseases in the cohort of miners was more than 2 times higher than the population indicator (SRR=2.18). A significantly higher frequency of deaths from this class of diseases indicates a causal relationship with dust loads. The prevalence of coronary heart disease (CHD) among coal mine workers is higher than among the unorganized population of large cities and other groups of industrial workers.
 Conclusion. Scientists have recorded the most unfavorable working conditions in underground coal mining, which is due to the technologies used and production conditions. The prevention of diseases among miners requires the creation of health groups and the improvement of medical examination methods. Development of an integrated information system for health monitoring and personalized preventive and rehabilitation measures. To solve this problem, it is necessary to study working conditions, scientifically substantiate preventive measures, harmonize special assessment of working conditions and develop criteria for severity and intensity of work, as well as improve the technology for assessing working conditions and personalized risk assessment.
 Ethics. The study did not require the conclusion of the Ethics committee.

Effectiveness of chemical road dust suppressants on paved roads of Pimpri Chinchwad

Introduction: Currently, reducing road dust emissions is a serious problem for safe and environment-protective transportation, leading to Particulate Matter (PM) limit violations and high population exposures to dust containing poisonous metals and mineral particles. Nowadays chemical road dust suppressants are being employed more frequently as a viable remedy to reduce roadside dust emissions.
 Materials and methods: Two seasons winter and summer were selected for the study and during which, typically 3 types of roads as per average traffic density and land-use category identified in the city of Pimpri-Chinchwad were sprayed. Dry samples were taken on day one from a 1 m2 area using a portable vacuum cleaner that was run for 8 to 10 min each. Similarly, samples were collected in the same area after 5-10 min after spraying with Calcium Chloride (CaCl ) and Magnesium Chloride (MgCl ). Also, the second set of 2 samples was collected after 24 h of chemical applied.
 Results: Maximum reduction in silt loading occurred i.e., 99.73% on the application of 30 g/m2 of CaCl . Reduction observed in emission factor of PM2.5 was 97.78% and in the case of PM10 it was 97.59%. While increase in average particle size was observed up to 27.88 µm.
 Conclusion: Both the suppressant efficient in suppressing the road dust but the day 1 result shows more dust suppression as compared to the day 2 dust suppression also as per the dust loading CaCl2 is a better dust suppressant than MgCl2.

Biogeochemical lichen indication study of formation and temporal changes of Oleksandriia Arboretum atmospheric pollution

Using the method of biogeochemical lichen indication the levels of the average long-term content of K, Ca, Al, Fe, Mg, Na, Mn, Zn, Sr, Ti, Ba Cu, B, Pb, Ni, V, Cr, Co, Cd, Se, Sb in surface air were measured on the territory of Olexandriia Arboretum and adjacent territories (Bila Tserkva, Kyiv Region, Ukraine). The purpose of the study is to determine the state and dynamics of the atmospheric geochemical field on the territory of Olexandriia Arboretum and its surroundings. The method of biogeochemical lichen indication based on the values of micro- and macroelements content in epiphytic lichens was used as a research tool. Application of the ICP-OES spectroscopy method allowed the analysis for chemical elements content of the samples of epiphytic deciduous Parmelia sulcata, Xanthoria parietina and bushy Evernia prunastri lichens collected in 2009 (20 points) and 2021 (23 points).
 In order to identify possible sources of entering of certain elements into lichens the researchers used the factor analysis method, i.e. a method of principal components with Varimax factors rotation. Six obtained factors represent: the impact of land cover (the most significant factors F1–F3) and man-made components (minor polygenetic, factors F4–F6). As a factor's number decreases, its partial explanatory variance decreases too. Factor F1 represents a common dust loading on the atmosphere with a predominance of the terrigenous component (mostly coarse-dispersed particles). Factor F1 is responsible for the dust-aerosol loading that is largely caused by the microclimatic circulation of the city breeze type thus forming a peculiar atmospheric and geochemical association that consists of chemical elements related to the building industry and building materials production. Powerful, however, local (impactful) atmospheric man-made influences manifest themselves through factor F3. Minor factors' discrimination ability reduces if a source of atmospheric pollution is less significant. Both division of factors into subfactors and noticeable temporal dynamics are observed more often. For instance, factor F4 has two geochemical sub-associations affected by the impact on the Olexandriia's landscapes of the 1990s' ecological disaster (fall-out of oil products, geochemical marker – V) and galvanic waste causing soil pollution (Zn, Mg, Cr, Ni and Ti), as well as discharges of agricultural enterprises (K). One of the peculiarities of F4 is a gradual decrease in its intensity over time. Factor F5 should be interpreted as the only load on the environment associated with galvanic pollution with cobalt being replaced by copper as a leading pollution marker. We suggest considering Factor F6 as a factor associated with oil pollution only.

Spectral reflectance of atmospheric dust as an indirect indicator of its soil origin

Atmospheric dust affects both human health and climate change. Therefore, the study of atmospheric dust is one of the important tasks of many scientific fields. The aim of our research was to indirectly assess the relation of atmospheric dust over arable lands of two test sites in Tver and Tula regions of Russia with soils. Dust was analyzed on aspirator filters after pumping specified volumes of air at the level of 20–30 cm above the arable surface. Its spectral reflectance was used as a criterion of soil origin of dust, which was compared with the reflectance of the size fraction (50–200 nm) of soils isolated by dry sieving of a sample of arable soil horizon. The spectral reflectance of dust was calculated based on approaches of linear separation of spectral mixture, taking into account the projective coverage of dust particles on filters, which was determined by analyzing microscope photographs of the filters in GIS. As a result, it was found that the recovered dust spectra on the filters correlate well with the spectra of the same size soil fraction separated by dry sieving, which indirectly confirms the predominance of specifically soil dust on the filters. Spearman correlation coefficient is within the range of 0.84–0.90, Kendall's Tau correlation coefficient varies within 0.70–0.79 (at significance level p < 0.05). Under the conditions of insignificant atmospheric dust load and when collecting a sufficient amount of dust for direct analysis is time and labour consuming, the approach used may serve as an alternative for indirect confirmation of the soil origin of dust in the near ground layer of the atmosphere. In the future, this approach can be used as a basis for monitoring of arable soils deflation.

Ce doped V-W/Ti as selective catalytic reduction catalysts for cement kiln flue gas denitration.

In cement industry, the selection of catalyst temperature window and the inhibition effect of dust composition in flue gas on catalyst are the key issues of flue gas denitrification. In this article, a pilot study with Ce doped V-W/Ti catalyst on the removal of NOx by selective catalytic reduction with ammonia (NH3-SCR) from the cement kiln flue gas was presented. Cement kiln dust loading on catalysts obviously decreased the NO conversion in the absence of SO2 and H2O, while the denitration efficiency restored from 75 to 98% at 280 ℃ after SO2 and H2O introduced into the reaction system, which mainly because the SO2 may enhance the acidic site on the catalyst surface, and prefer to be bonded with the coordinated Ca species, releasing the active sites poisoned by dust. The NH3-temperature programmed desorption (NH3-TPD), X-ray photoelectron spectroscopy (XPS), and H2-temperature programmed reduction (H2-TPR) detections were performed to reveal that the appropriate Ce and W ratios catalyst contributed better denitrification activity. The optimum ratio of Ce doped catalyst was amplified to form the standard honeycomb monomer catalyst, and then, the activity of catalyst was verified on the side line of cement kiln. The effect of temperature and space velocity on denitrification efficiency was investigated, and the denitration efficiency reached to 92.5% at 300℃ and 3000h-1 space velocity. Moreover, the life of catalyst was verified and predicted by GM (1,1) grey model. The study realized the innovation from the laboratory data rules to the industrial pilot application, providing positive promoting value for the industrial large-scale demonstration application of the catalyst.

Условия и режимы обработки технологического процесса маслонаполнения полимерных деталей

A large number of polymer parts, used in railway transport, operating in difficult conditions, significantly wear off caused by conditions in open friction units, having dust loading and other contamination without any liquid lubrication. Existing technologies, used for solving this problem, aimed at making just the material of the part, which results in a change in the operational properties of the whole part, but there is no technology that will be useful in changing the operational properties of the surface layer itself. In order for a decision to be adopted on, a new procedure specification is being developed to improve the performance characteristics of ready-made polymer parts. This technology consists in filling their surface layer with an oil mixture to a given depth of approved wear. One of the most important stages in the development of this technological process is the determination of various conditions and operating modes necessary to ensure the parameters of this operating procedure. For that purpose, the objective function of two parameters is formed in the work. In this paper, the criteria for evaluating the parameters of the specification procedure of oil filling are determined. The analytical calculations and experimental studies are performed for the boundary delimination of the parameters and temperature limits for the application of the filling mixture based on the temperature of its boiling and evaporation of hexane. Due to certain initial and boundary conditions, the recommended operating modes for performing the specification procedure of oil filling are determined. The result of the work was the determination of the specific boundaries of the objective function of two parameters and the order of the stages of the procedure, which allows ensuring its stability and performance.

An eight-year climatology of the martian northern polar vortex

The martian polar atmosphere is characterised by the presence of polar vortices, regions of cold and isolated air over the winter poles common to planetary atmospheres. The polar vortices have important meteorological effects via their interactions with atmospheric tracers and the broader circulation. In turn, they have been shown to be affected by large atmospheric dust loadings such as from dust storms. We make use of an extensive reanalysis dataset of Mars’ weather and climate (Open access to Mars Assimilated Remote Soundings; OpenMARS) to investigate the seasonal and interannual behaviour of Mars’ northern polar vortex over eight recent martian years, Mars Years (MY) 28–35 (2006–2021). We find that the northern polar vortex shows a high degree of interannual repeatability in its structure and evolution, with the key exception of during the presence of large (regional and global scale) dust storms. Such storms cause significant perturbations to the northern polar vortex, compressing it towards the pole and reducing its radius. However, not all dust storms have equal impacts. We find that the seasonal timing of large dust storms appears to be the key factor determining their impacts on the northern polar vortex. Storms occurring closer to southern summer solstice have greater impacts than those occurring closer to equinox. We propose that this seasonal dependence is due to the structure of the background meridional circulation, which is at its greatest strength and latitudinal extension around southern summer solstice. The enhancement of this existing circulation by dust-induced heating allows greater impacts if the circulation is already stronger and more latitudinally extended, and impacts are likewise lesser if the storm occurs during a period with a weaker and less latitudinally extended circulation.

The Importance of Isentropic Mixing in the Formation of the Martian Polar Layered Deposits

Layers of ice and dust at the poles of Mars reflect variations in orbital parameters and atmospheric processes throughout the planet's history and may provide a key to understanding Mars's climate record. Previous research has investigated transport changes into the polar regions and found a nonlinear response to obliquity that suggests that Mars may currently be experiencing a maximum in transport across the winter poles. The thickness and composition of layers within the polar layered deposits (PLDs) are likely influenced by changes in horizontal atmospheric mixing at the poles, which is an important component of the transport of aerosols and chemical tracers. No study has yet investigated horizontal mixing alone, which may be influenced by polar vortex morphology. We show that mixing in an idealized Martian global climate model varies significantly with obliquity and dust abundance by using a diagnostic called effective diffusivity, which has been used to study the stratospheric polar vortices on Earth and to understand their role as a mixing barrier but has not been applied to Mars's polar vortices. We find that mixing in the winter southern hemisphere doubles with either an octupling of dust loading or an increase in obliquity from 10° to 50°. We find a weaker response to changing dust loading or obliquity in the northern hemisphere. We demonstrate that horizontal mixing is an important component of transport into Mars’s polar regions, may contribute to the formation of the PLDs, and presents effective diffusivity as a useful method to understand mixing in the Martian atmosphere.

A comprehensive investigation of the causes of drying and increasing saline dust in the Urmia Lake, northwest Iran, via ground and satellite observations, synoptic analysis and machine learning models

Nowadays, dried lakes have turned into important dust sources with serious environmental, climatic and socio-economic impacts. In this study, climatic, terrestrial and anthropogenic effects that caused desiccation of the Urmia Lake, NW Iran are investigated. The main objective is to assess the influence of climatic and regional factors against anthropogenic and local ones in the dryness of the lake during the last two decades. Annual temperature, precipitation and wind speed data measured at nearby meteorological stations, along with water discharge of eight main rivers flowing into the lake are analyzed. The results reveal that the main cause for turning Urmia into a dried lake bed was human interference, since climatic factors contributed positively but to a lesser degree, while terrestrial factors may also play a crucial role. Among anthropogenic interferences, the construction of a causeway had a weak effect in the lake's dryness, while construction of many river dams highly contributed to this disaster. Furthermore, four machine learning models showed that groundwater decline is also an important factor for lake's desiccation. Analysis of dusty days at stations in the Urmia Basin showed similar inter-annual and seasonal dust variability over the whole western Iran. This indicates that dust over the Urmia Basin is mainly affected by the regional dust activity, while the dried lake beds contribute to a lesser degree to the enhanced dust loading. The dominant wind flow is mostly southwesterly, carrying Urmia saline dust toward NE directions, affecting Tabriz city. Three main synoptic clusters, with dipole features consisted of high-pressure systems over Europe, Central Mediterranean and North Africa and low pressure over SW Asia, facilitated strong westerly winds from arid, desert areas of the Middle East toward the Urmia Basin during 118 dust storms in the region.

Impact of dust load and lead (Pb) stress on leaf functioning of urban vegetation

Impact of dust load and lead (Pb) stress on leaf functioning of urban vegetation

Mineral magnetic proxies for evaluation of anthropogenic pollution at children's playgrounds – a case study from Sofia city

Quality of the urban environment where children play is of great concern for protecting their health. Thus, fast and economically feasible proxy methods for assessment of urban environment are increasingly applied. In this study, settled dust from 13 playgrounds from Sofia city (Bulgaria), was investigated by mineral magnetism, portable X-ray fluorescence measurements, and scanning electron microscopy. The aim of the study was to evaluate the degree of anthropogenic pollution of playgrounds during winter and summer seasons and to identify pollution sources. Magnetic susceptibility (χ) was measured for two dust fractions - very coarse (grain sizes between 1 and 2 mm) and size fraction of d < 1 mm. In spite of this rough separation, systematic seasonal difference in χ of the two fractions is observed. Winter dust, containing larger amount of finer fraction shows lower χ. Regardless of lower relative content of d < 1 mm fraction, summer playground dusts are more strongly magnetic. Complex Pollution Load Index (PLI), calculated using contents of Cu, Zn, S, Pb (Potentially Toxic Elements (PTE)), shows higher contamination in summer dust, compared to winter. Anhysteretic and isothermal remanences of dust d < 1 mm demonstrate prevailing magnetically stable grains at playgrounds located at greater distance from major boulevards. Thermomagnetic analyses of magnetic susceptibility identified magnetite as the main magnetic mineral, although metallic iron was also evident in summer dust. Based on the meteorological models of atmospheric circulation over Sofia, the pollution sources suggested in a previous research, on one hand, and the carried out Factor Analysis, on the other hand, the results point out that in spite of higher PM10 dust load in winter, summer dust pollution causes stronger PTEs contamination. Factor analysis revealed four factors, explaining most of variability in the data. These factors were identified as: 1) re-suspension of soil and road dust; 2) fine particles magnetite of stable single domain grain size, originating probably from traffic exhaust and non-exhaust emissions; 3) emissions from installations burning waste materials; 4) coal burning.

Effects of various wet environments on the characteristics of the dust cake deposited on the surface of filter media

The effect of wet environments on the dust cake of filter media was studied. The collapse angles of dust particles and the collapse angles between dust particles and filter media increase with increasing dust moisture content, relative humidity, and spray rate. The smallest growth rate of collapse was observed under dust moisture content, while the largest growth rate occurred under the spray rate condition. The collapse angles between dust particles and filter media of coated filter media were smaller compared to those of mechanical filter media under different wet environments. The dust cake drag coefficients of both filter media initially increase and then decrease with an increase in the dust moisture content, decrease with the acceleration of the relative humidity, and show a pattern of first decreasing and then increasing as the spray rate increases. The dust loading capacity of both filter media follows an opposite trend to that of the dust cake drag coefficients.

Martian Equatorial Atmospheric Tides From Surface Observations

AbstractDiurnal solar radiation causes global oscillations in pressure, temperature, and wind fields, known as atmospheric tides, which are further modified by topography, surface properties, and atmospheric dust loading. Hence, the tides are a combination of sun‐synchronous and non sun‐synchronous tides that propagate around the planet both eastward and westward. In the Martian tropics, atmospheric tides dominate daily pressure variations on the surface. Therefore, surface observing platforms are extremely useful for detailed analysis of atmospheric tides. In this investigation, we analyze diurnal and semi‐diurnal components of atmospheric surface pressure measured by the simultaneously operating InSight and Mars Science Laboratory (MSL) payloads. We utilize observations of the time period from Martian year (MY) 34 solar longitude 296° to MY 36 solar longitude 53°. The diurnal tide average amplitude is 17 Pa with an average phase of 03:39 local true solar time (LTST), while the semi‐diurnal tide average amplitude and phase are 7 Pa and 09:34 LTST for the InSight. The corresponding values for the MSL are 33 Pa with 04:25 LTST for the diurnal and 10 Pa with 09:36 LTST for the semi‐diurnal component. Thermo‐topographic lateral hydrostatic adjustment flow generated by topography causes the higher diurnal amplitude observed by MSL. Both platforms observe a similar response between these harmonic components and dust loading. Furthermore, amplitudes obtained from a Mars Climate Database mimic the observations well. Our study provides for the first time a comparison of atmospheric tides at two simultaneously observing tropical surface platforms for more than 1 MY.

The Mars Science Laboratory record of optical depth measurements via solar imaging

The Mars Science Laboratory Curiosity rover has monitored the Martian environment in Gale crater since landing in 2012. This study reports the record of optical depth derived from visible and near-infrared images of the Sun. Aerosol optical depth, which is mostly due to dust but also includes ice, dominates the record, with gas optical depth too small to measure. The optical depth record includes the effects of regional dust storms and one planet-encircling dust event, showing the expected peaks during southern spring and summer and relatively lower and more stable optical depth in fall and winter. The measurements show that there is a seasonally varying diurnal change in dust load, with the optical depth peaking in the morning during southern spring and summer, correlated with thermotidal pressure changes. However, there was no systematic diurnal change during autumn and winter, except after one regional storm. There were indications that the dust was relatively enhanced at high altitudes during high-optical-depth periods and that high-altitude ice was significant during winter. The observations did not provide much information about particle size or composition, but they were consistent with a smaller particle size after aphelion (in southern winter). No scattering halos were seen in associated sky images, even when there was visual evidence of ice hazes or clouds, which suggests small or amorphous ice particles. Unexpectedly, the measurement campaign revealed that the cameras collected saltating sand in their sunshades 1.97 m above the surface. As a result, the measurement strategy had to be adjusted to avoid high-elevation imaging to avoid sand covering the optics.

Preliminary assessment of road dust from Portuguese motorways: chemical profile, health risks, and ecotoxicological screening

Among non-exhaust emissions, road dust resuspension represents a rather important contribution to particulate matter in urban areas. This study aimed to achieve a chemical characterisation of road dust particulate matter (PM10) on two motorway sections, one rural and one urban, and to explore the related health and ecotoxicological risks. Measured PM10 dust loadings reached very low levels (0.66–1.49 mg m-2) compared to equivalent studies in other road environments in Portugal and other countries. Emission factors ranged from 33 to 62 mg veh−1 km−1. The carbonaceous content represented 14% of the total PM10 mass, whereas the highest contribution to the mass was given by mineral matter. Elements such as Si, Al, Ca, Fe and K accounted for almost three quarters of the total element mass for all samples, whilst Cu and Zn, mostly associated with brake and tyre wear, were the most enriched elements in relation to the soil composition. Nonetheless, Ti and Zr presented the highest non-carcinogenic risks for human health. Despite the low amounts of particulate matter in the aqueous solution, the ecotoxicological screening with the Aliivibrio fisheri bioluminescence inhibition bioassay allowed to classify the samples as toxic.