Deposition Of Particulate Matter Research Articles

Numerical simulation of the dual-loop different velocity air curtain system in the operating room

The problem of cross-infection between patients and surgeons in the operating room had been widely concerned by the international community. The purpose of this study had been to explore the potential of a Dual-loop Different Velocity Air Curtain System (DDVACS) being applied in the operating room to reduce cross-infection. In this study, the performance of the system was studied using the computational fluid dynamics (CFD) numerical simulation method, with the operating conditions of different air supply velocities inside and outside being set. The RNG k-ε model, Discrete Phase Model (DPM), and Species Transport model were used to simulate the air distribution, particle diffusion, and virus diffusion. The main research results showed that, when the DDVACS was operated at an inner air supply velocity of 0.24 m/s and an outer air supply velocity of 0.45 m/s, the virus concentration in the surgical area had decreased by 89%, the particulate matter concentration in the surgical area had decreased by 78.08%, but the deposition of particulate matter had increased by 21.62%. This study concluded that DDVACS had been found to effectively reduce the concentration of cross-infection. Finally, the velocity difference between the inner and outer sides was controlled within 2 times. This setting had been arranged to make the DDVACS work better. This study's contribution was to further verify the application of the DDVACS in operating rooms, providing a new perspective and empirical support for related fields and possessing certain practical application value.

Particulate matter retention and removal efficiency in ten tree species of semi-arid environment

Modern era has witnessed particulate matter (PM) become one of the biggest threats for the existence of biological species. Therefore, a study was performed in Faisalabad city to evaluate PM retention and removal efficiency of ten local tree species. Branch samples were collected from urban, sub-urban and rural areas in September 2020 (183 days after rain), and in August 2021 (30 days after rain). Results showed that total PM load, PM>10 and PM10-2.5 retention was the highest in urban followed by sub-urban and rural area. PM>10, PM10-2.5, total PM, and PM deposition rate decreased significantly in the following order, F. benghalensis > T. arjuna > S. cumini > A. scholaris > F. religiosa > E. camaldulensis > D sissoo > C lancifolius > B. ceiba > M. alba during both years 2020, and 2021. During the artificial rainfall experiment, total PM removed by the species also followed the same order however, PM removal efficiency was the highest in B. ceiba and M. alba followed by E. camaldulensis, C. lancifolius, D. sissoo, T. arjuna, S. cumini, A. scholaris, F. religiosa and F. benghalensis. Therefore, it can be concluded that species selection must be done skillfully for congested urban environment.

Removal of airborne particulate matter by evergreen tree species in Dhaka, Bangladesh

Urban air quality stands as a pressing concern in cities globally, with airborne particulate matter (PM) emerging as a significant threat to human health. An investigation was carried out to examine the potential of four prevalent evergreen roadside tree species grown at different locations in Dhaka to capture PM using their leaves. The distribution of PM by mass and quantity in Dhaka are presented for the first time for Bangladesh and these results will also be applicable to countries with similar climates and tree species. Separate gravimetric analyses were carried out to quantify PM in three different size ranges (0.2–2.5 μm, 2.5–10 μm, and 10–100 μm) accumulated on surfaces and trapped within waxes by using the rinse and weigh method. The method is validated for the first time through SEM-EDX analysis, which confirmed that the increase in weight from chloroform-rinsed leaves was exclusively attributable to particle deposition on the filter. The chemical composition of the deposited PM2.5 was analyzed quantitatively by determining the concentration of twenty-five trace elements employing ICP-MS. SEM-EDX analysis revealed the significance of leaf microstructural traits in effectively capturing PM. Significant variations in the deposition of PM were found among different species for two PM categories (surface PM and wax-embedded PM) and three size fractions (large, coarse, and fine) (one-way ANOVA; p < 0.05). The quantity of wax retained on the foliage of trees documented in these locations also varied (p < 0.05). Among the species studied, Ficus benghalensis demonstrated a greater ability to retain PM. Mangifera indica was identified to be the most efficient collector of wax-related PM and appears to be the ideal species for traffic-heavy areas distinguished by high concentrations of organic compounds from vehicle emissions.

A comparative analysis of an aerosol dry deposition microscale model for overhead powerlines insulators

Aerosol particles deposition on overhead power line insulators may significantly threaten electric systems, affecting dielectric properties and potentially causing surface discharges and service interruptions, leading to economic consequences. This study addresses this challenge by evaluating a dedicated microscale deposition model that integrated into an advanced air quality (AQ) modeling system. The microscale model integration into the AQ system aims to improve predictions of equivalent salt deposit density (ESDD), a key measure of insulator contamination. This enhancement is crucial for improving system resilience and reliability. The microscale model’s performance in reconstructing particulate matter (PM) deposition fluxes onto XP-70 porcelain-disk electrical insulator is assessed against measured ESDD data collected across various regions in Italy during several experimental campaigns. In order to better understand the specific phenomena impacting PM deposition, the microscale model is compared to the state-of-the-art Zhang deposition model used in CAMx. The analysis reveals that the microscale model tends to overestimate measured ESDD values and predicts higher deposition velocities than the Zhang model. These results suggest potential modelling differences between the two models, including variations in obstacle parameterizations, influence of particle aerodynamics, and dispersion modelling in the near-wall region.

Experimental and numerical analysis of particulate matter deposition in DPF for different blends of Algae Bio diesel

The stringent emission norms have compelled to use Diesel particulate filter (DPF) to reduce particulates emission in automotive Diesel engine. The back pressure developed in the DPF due to the Particulates matter (PM) deposition in porous zone degrades the diesel engine’s performance. So, there is a need of a fuel which should produce less particulates on combustion as well as its produced particulates should be easy to get regenerated inside the DPF. Three different Algae biodiesel blends B20, B40 and B60 were selected for the study, while the results are compared with the diesel fuel. A numerical study has been done with diesel and Algae biodiesel blends to investigate the effect of PM deposition on the DPF performance. The results of PM concentration and the pressure drop has been predicted for t = 2000s. and compared with the results predicted for diesel fuel. The summarized velocity contours and the PM concentration plots show that a maximum of the PM concentration was found in the diesel fuel case, while the lower found in B60 algae blend. Also, the pressure drop was found to increase with the increase in PM deposition in each case of fuel. The SEM-EDS analysis is done after collecting PM samples after combustion shows a higher percentage of Oxygen and lower Carbon with an increment of Biodiesel in the blend. This work provides a brief idea about the PM deposition in DPF while using Diesel and Algae Biodiesel blends and highlighting the better fuel option for Diesel Engine.

Assessing the efficacy of green walls versus street green lanes in mitigating air pollution: A critical evaluation

Urban green spaces, particularly street trees and greenways, are increasingly recognized as tools for mitigating air pollution. However, their effectiveness can vary depending on their configuration and urban canyon geometry. This study, aimed at providing practical solutions, assessed the impact of different green space configurations, including street trees, green lanes, green walls, and hedges, on particulate matter (PM) concentrations within urban canyons of varying aspect ratios by employing environmental simulations and wind tunnel tests performed in ENVI-met software.Results demonstrate that green walls significantly outperform street trees in reducing PM concentrations by up to 43%, attributing this to reduced air flow disruption. Green walls also create a more uniform PM distribution within canyons, decreasing concentration differences by 31% compared to green (tree) lanes. Conversely, dense tree lanes exacerbate PM deposition due to wind flow interference.These findings suggest that incorporating green walls into urban design can be a highly effective strategy for improving air quality within densely built environments.

Effect of ash-bridge deposition in asymmetric diesel particulate filter channels on the pressure drop and particulate matter trapping characteristics

A diesel particulate filter (DPF) is commonly used to trap particulate matter (PM). The collapse and sintering of carbon and ash deposits during exhaust gas flow and DPF regeneration frequently result in the formation of ash bridges, which are buildups of ash and PM that clog the filter channels. To investigate the impact of an ash bridge formed by accumulated ash on the pressure drop and PM trapping characteristics of asymmetric DPFs, an asymmetric DPF channel with an ash bridge was constructed. The analysis employed computational fluid dynamics to examine how the ash bridge affects the pressure drop and PM trapping characteristics in an asymmetric DPF. This study reveals that the asymmetric DPF design effectively enhances the ash-holding capacity, thereby mitigating the risk of channel blockage. The presence of ash bridges in DPF channels has a more substantial impact on the pressure drop through radial congestion than through axial congestion. The application of asymmetric thin-wall DPFs can counteract the increase in exhaust backpressure caused by ash bridges. An ash bridge located in the middle of a DPF channel intensifies the uneven deposition of PM. However, implementing an asymmetric DPF structure enhances the uniformity of PM deposition.

Heavy Metal Exposure-Mediated Dysregulation of Sphingolipid Metabolism.

Exposure to heavy metals (HMs) is often associated with inflammation and cell death, exacerbating respiratory diseases including asthma. Most inhaled particulate HM exposures result in the deposition of HM-bound fine particulate matter, PM2.5, in pulmonary cell populations. While localized high concentrations of HMs may be a causative factor, existing studies have mostly evaluated the effects of systemic or low-dose chronic HM exposures. This report investigates the impact of local high concentrations of specific HMs (NaAsO2, MnCl2, and CdCl2) on sphingolipid homeostasis and oxidative stress, as both play a role in mediating responses to HM exposure and have been implicated in asthma. Utilizing an in vitro model system and three-dimensional ex vivo human tissue models, we evaluated the expression of enzymatic regulators of the salvage, recycling, and de novo synthesis pathways of sphingolipid metabolism, and observed differential modulation in these enzymes between HM exposures. Sphingolipidomic analyses of specific HM-exposed cells showed increased levels of anti-apoptotic sphingolipids and reduced pro-apoptotic sphingolipids, suggesting activation of the salvage and de novo synthesis pathways. Differential sphingolipid regulation was observed within HM-exposed lung tissues, with CdCl2 exposure and NaAsO2 exposure activating the salvage and de novo synthesis pathway, respectively. Additionally, using spatial transcriptomics and quantitative real-time PCR, we identified HM exposure-induced transcriptomic signatures of oxidative stress in epithelial cells and human lung tissues.

Size-resolved particulate matter inside selected fire stations and preliminary evaluation of the effectiveness of washing machines in reducing its concentrations

The study aimed to determine and compare the mass concentration and size distribution of particulate matter (PM) at two Polish fire stations, one equipped with a washing machine intended for the decontamination of uniforms (FSN) and the other not equipped with this type of device (FSC), to assess the effectiveness of washing machines in reducing PM concentrations inside fire stations and estimate PM doses inhaled by firefighters while performing activities in truck bays and changing rooms during one work shift. The average PM concentrations at the FSN were 18.2–28.9 µg/m3 and 27.5–37.3 µg/m3, while at FSC they were 27.4–37.9 µg/m3 and 24.6–32.8 µg/m3 in the truck bays and changing rooms, respectively. At each measurement point, most of the PM mass (65–75%) was accumulated as fine particles. The dominance of fine particles in the total mass of PM results in high values of PM deposition coefficients (0.59–0.61) in three sections of the respiratory tract at each monitoring site. This study initially indicates the effectiveness of washing machines in reducing the concentration of fine particles and demonstrates the necessity, as well as directions for further research in this area.

Analysis of carbon and nitrogen from atmospheric sources by bulk deposition sampling at various locations in Germany

Atmospheric deposition of particulate matter is an important indicator of air pollution and a significant factor in material surface fouling. The elemental composition of this nutrient-containing dust depends largely on the exposure region and time as well as on climate. Therefore, in this paper we report an analysis of atmospheric pollutions with a self-made low-cost bulk deposition sampler directed at sampling deposition via air transport and rainfall. We used the device in diverse environments - thus comparing an urban region, an area surrounded by forest and an area mainly dominated by agriculture. The total organic carbon (TOC) and total nitrogen (TN) amounts were selected as indicator parameters and analyzed in a biweekly rhythm for three and a half and two years, respectively. The TOC value responded to particulate matter in the urban area, especially significant were the influences of the New Year's firework in urban and pollen in the rural forest area. In contrast, the TN value was more under the influence of the nitrogen emissions in the agriculture-dominated area. However, the TN value did not correlate with the NOx values in the urban area because the atmospheric nitrogen emissions in the city might originate from various emission sources. Summarizing, the TOC and TN values of the self-made low-cost bulk deposition sampler were in good agreement with environmental events of their immediate surrounding. Moreover, the selected containers and sampling procedures are universally applicable to monitor and analyze organic as well as inorganic parameters (e.g. metal ions) of atmospheric deposition.

Particulate matter hinders the development and reproduction of predatory mites of Euseius finlandicus (Acariformes: Phytoseiidae)

The foliage of the small-leaved lime (Tilia cordata) is characterised by the nerve axils being grown by non-glandular trichomes, which trait contributes to the enhanced retention of the particulate matter (PM). This fact may disturb the ecological service of T. cordata related to the structure of its leaves, which is to provide acarodomatia (micro-shelters) for the predatory mites of the Phytoseiidae family. Phytoseiids are natural enemies of a variety of plant pests, widely applied in integrated pest management (IPM). Their occurrence is largely related to acarodomatia in which these mites hide, feed, reproduce, and develop. For the first time, the influence of PM deposition within spaces typically occupied by phytoseiids is investigated. Experimental populations of Euseius finlandicus were reared on T. cordata leaves in the progressive PM-pollution. The results showed that the values of life table parameters of the predator depended significantly on the level of PM deposition on leaves. Contrary to clean leaves from the control, the medium and high contamination intensities significantly reduced the daily (by 47% and 70%, respectively) and the total fecundity (by 62% and 77%, respectively) of females which, in turn, resulted in a decreased net reproductive rate (by 67% and 81%, respectively), intrinsic rate of increase (by 40% and 55%, respectively) and finite rate of increase (by 8% and 10%, respectively) of E. finlandicus. The pre-ovipositional period was prolonged, while the oviposition duration was shortened and the mites matured longer. In high pollution level the mortality of phytoseiids was boosted by 19% and some females were observed with pollutant lumps adhered to the idiosoma. Also, significant shares of juvenile forms (13%) and adult females (25%) made attempts to escape from highly contaminated experimental arenas. The implications of PM retention on the shelter vegetation are discussed in the context of IPM and ecological services.

Dry Deposition in Urban Green Spaces: Insights from Beijing and Shanghai

Urbanization and industrialization have escalated air pollution into a critical global issue, particularly in urban areas. Urban green infrastructures (GIs), such as parks and street trees, play a vital role in mitigating air pollution through dry deposition, the process by which air pollutants are removed by deposition onto plant surfaces or through plant uptake. However, existing studies on the dry-deposition capacity of urban green spaces are limited in their ability to reflect variations at the tree-species level, hindering comprehensive evaluations and effective management strategies. This study aims to quantitatively assess the dry-deposition capacity of the urban green spaces of Beijing and Shanghai for six major air pollutants in using an improved dry-deposition model and tree-species-specific data. Results showed that Shanghai’s urban green spaces had a monthly average dry-deposition rate of 5.5 × 10−6 s m−1, slightly higher than Beijing’s rate of 5.3 × 10−6 s m−1. Significant seasonal variations were observed, with summer showing the highest deposition rates due to favorable meteorological conditions. Broad-leaved species such as Zelkova serrata in Beijing and Photinia serratifolia in Shanghai exhibited superior dry-deposition capacities compared to coniferous species. Temperature significantly influenced dry-deposition rates for gaseous pollutants, while particulate-matter deposition was primarily affected by pollutant concentrations. This study provides critical insights into the air = purification functions of urban green spaces and underscores the importance of species selection and strategic green-space planning in urban air-quality management, informing the development of optimized urban-greening strategies for improved air quality and public health.

Reliability analysis of thermal barrier coatings under CMAS deposition and penetration

To address the issue of thermal barrier coating (TBC) failure and spalling caused by the deposition and infiltration of environmental particulate matter, a thermal-mechanical coupling model for EB-PVD TBC considering CMAS deposition failure was developed. Based on this model, the effects of CMAS deposition thickness and infiltration depth on TBC spalling failure were numerically studied. First, the deposition characteristics of CMAS were obtained using a critical velocity model. Second, the corresponding TBC failure criteria were established. Then, the effects of CMAS deposition thickness and infiltration depth on TBC spalling failure were specifically studied under different CMAS particle sizes and service times. The results show that the CMAS deposition thickness is the greatest at the leading edge and the pressure surface near the trailing edge of the blade. The CMAS infiltration depth is influenced by the temperature field, with higher temperatures leading to greater infiltration depth. With the simultaneous increase of service time and particle size, the average damage value of the coating surface (D¯) initially increases slightly to 0.2, then rapidly to 0.9, and finally slowly to 0.97, resulting in almost complete failure and spalling of the coating.

Urban meadow—a recipe for long-lasting anti-smog land cover

This study evaluates for the first time whether 33 species of annual and perennial herbaceous plants originating from a moderate climate continue to be capable of air filtration of particulate matter (PM) at the end of the growing season. Research was undertaken in November in two urban meadows located in trafficked areas of Białystok (Poland). The study reveals that despite the lateness in the season, tested species remained capable of PM accumulation. Deposition of total PM exceeding 100 μg·cm−2 was found on S. vulgaris, S. latifolia, T. pratense, E. vulgare, and A. officinalis. The finest and most toxic fraction was accumulated most effectively by S. latifolia, E. vulgare, and L. vulgare (>12 μg·cm−2). Taraxacum officinale and M. sylvestris retained c. 60% of PM in their epicuticular wax. A slight significant correlation was found between rosette growth pattern and deposition of total PM on foliage, while the accumulation of the finest fraction was correlated with a simple leaf shape. These results support the usefulness of urban meadows as long-lasting air bio-filters provided that their composition includes species that have a confirmed, prolonged PM accumulation capacity and that the meadow is not mown in autumn.

Investigating the influence of particle hydrophobicity on lung deposition using nonionic dye partitioning

The regional deposition of inhaled particulate matter (PM) in the respiratory tract determines its biological fate and lung toxicity. While it is widely accepted that the size of PM plays a predominant role in affecting lung deposition, the impact of other physicochemical properties, especially hydrophobicity, remains unclear. This knowledge gap exists, in part, due to the absence of standard methods to characterize the hydrophobicity of PM. Here, we developed a novel nonionic dye partitioning method to quantitatively characterize the hydrophobicity of PM. The use of a nonionic dye, rhodamine B, effectively eliminates experimental artifacts arising from unwanted dye adsorption due to electrostatic interactions, thus significantly improving the accuracy and applicability of the method. Through an intranasal mouse exposure model, we discovered that the lung deposition of four types of PM originated from common anthropogenic sources, including PM2.5, dust, biochar, and carbon black, is mediated by their hydrophobicity. The most hydrophobic PM tends to be trapped in the nasal cavity, whereas the least hydrophobic PM penetrates deep into the alveoli, inducing severe lung inflammation. The hydrophobicity-dependent deposition of PM in the respiratory tract offers novel insights into understanding the acute lung toxicity of inhaled PM and provides a foundation for the design of safer and more efficacious inhalable medicines. Furthermore, the nonionic dye partitioning method shows promise as a user-friendly and cost-effective approach for characterizing the hydrophobicity of PM.

Flexible Permeable-Pavement System Sustainability: A Methodology for Stormwater Management Based on PM Granulometry

Permeable-pavement design methodologies can improve the hydrologic and therefore the environmental benefits of rural and urban roadway systems. By contrast, conventional impervious pavements perturb the hydrologic cycle, altering the relationship between the rainfall loading and runoff response. Impervious pavements create a hydraulically conductive interface for the transport of traffic-generated chemicals and particulate matter (PM), deleteriously impacting their proximate environments. Permeable-pavement systems are countermeasures to mitigate hydrologic, chemical, and PM impacts. However, permeable pavements are not always equally implementable due to costs, PM loadings, and design constraints. A potential solution to facilitate environmental benefits while meeting the traffic load capacity is the combination of two filtration systems placed at the pavement shoulders and/or pedestrian sidewalks: a bituminous-pavement open-graded friction course (BPFC) and an aggregate-filled infiltration trench. This solution is presented in this manuscript together with the methodological framework and the first results of the investigations into designing and validating such a combined system. The research was conducted at the laboratories of the Polytechnic University of Bari and the University of Florida, while an operational and full-scale physical model was constructed in Bari, Italy. The first results presented characterize the PM deposition on public roads based on granulometry (particle size distributions (PSDs) and particle number densities (PNDs)). Samples (n = 16) were collected and analyzed at eight different sites with different land uses, traffic, and pavements from different cities (Bari and Taranto, Italy). The PM analysis showed similar distributions (PSDs and PNDs), except for two samples. The gravimetric-based PSDs of the PM had granulometric distributions in the sand-size range. In contrast, the PNDs, modeled by a Power Law Model (PLM) (R2 ≥ 0.92), illustrated an exponentially increasing number of particles in the fine silt and clay-size range, representing less than 10% of the PSD mass. Moreover, the results indicate that PM sourced from permeable-pavement systems has differing impacts on the pavement service life.

Evaluation of Particulate Matter Deposition Efficiency and Air Quality Improvement by Vertical Shrub and Climber Walls

Fine particulate matter poses a significant health risk indoors, making indoor air quality improvement crucial. Vertical greenery systems offer a promising solution, but selecting suitable plant species remains a challenge. This study evaluated the PM deposition and air quality impact of six ornamental plants (climbers and shrubs) in a controlled chamber. Almost all plants reduced CO2 by 20%, while PM deposition varied by species, with Petunia hybrid being the most efficient. Total leaf area showed the strong correlated with PM deposition. These findings confirm the potential of ornamental plants, particularly those with large total leaf area, for PM reduction in vertical greenery systems. Further research with a wider range of plants and advanced characterization techniques is needed to refine our understanding and develop practical guidelines for their effective use in indoor air purification.

A CFD numerical simulation of particle deposition characteristics in automobile tailpipe: power abatement pathways

The study of the movement of pollutants through ducts facilitates the assessment and control of ambient air quality problems (AQ). Among other things, understanding the deposition and distribution of particulate matter in elbows is important for practical engineering applications. In this study, the turbulent flow field and particle deposition in a 90° bend is investigated using RANS simulation. The RNG k-ε turbulence model was employed to calculate the airflow flow field and the discrete phase model (DPM) was used to simulate the particle phase motion. Where for the discrete phase, the Discrete Random Wander (DRW) model was considered and the deposition of particles with sizes of 1, 3, 5, 10, 20, and 40 μm in the flow field was investigated separately. Grid-independent validation of the models used in the simulations was performed. The effects of inlet velocity, particle size, and direction of gravity on the flow field and particle deposition in the elbow were considered. The results show that the flow field in the bend is strongly influenced by the above parameters. Among them, the turbulent disturbance in the bend section is the most intense, with high turbulent energy value, and it is also the region with the largest energy loss. The inlet velocity is negatively correlated with the deposition rate, and the particle size is positively correlated with the deposition rate.

Oxidative potential associated with reactive oxygen species of size-resolved particles: The important role of the specific sources

Oxidative potential (OP) is a predictor of particulate matter (PM) toxicity. Size-resolved PM and its components that influence OP values can be generated from several sources. However, There is little research have attempted to determine the PM toxicity generated from specific sources. This paper studied the OP characterization and reactive oxygen species (ROS) formation of particles from specific sources and their effects on human health. OP associated with ROS of size-resolved particles was analyzed by using dithiothreitol (DTT) method and electron paramagnetic resonance (EPR) spectroscopy technology. And OP and ROS deposition of specific source PM were calculated for health through the Multi-path particle deposition (MPPD) model. The results evidenced that the highest water-soluble OP (OPws) from traffic sources (OPm: 104.50 nmol min−1·ug−1; OPv: 160.15 nmol min−1·m−3) and the lowest from ocean sources (OPm: 22.25 nmol⋅min−1⋅ug−1; OPv: 54.16 nmol min−1·m−3). The OPws allocation in PM from different sources all have a unimodal pattern range from 0.4 to 3.2 μm. ROS (·OH) displayed the uniform trend as PM OPws, indicating that PM< 3.2 is the major contributor to adverse health impacts for size-resolved PM because of its enhanced oxidative activity compared with PM> 3.2. Furthermore, this study predicted the DTT consumption of PM were assigned to different components. Most DTT losses are attributed to the transition metals. For specific sources, transition metals dominates DTT losses, accounting for 38%–80% of DTT losses from different sources, followed by Hulis-C, accounting for 1%–10%. MPPD model calculates that over 66% of pulmonary DTT loss comes by PM< 3.2, and over 71% of pulmonary ROS generation from PM< 3.2. Among these sources of pollution, traffic emissions are the primary contributors to reactive oxygen species (ROS) in environmental particulate matter (PM). Therefore, emphasis should be placed on controlling traffic emissions, especially in coastal areas.

His dark materials: Quantifying the problem of dust (particulate matter) in the agricultural landscape of California

The composition and amounts of dust or particulate matter (PM) vary greatly in the atmosphere and particulates can have major adverse impacts on human health. Since PM10 deposition to foliage can improve air quality, there have been a number of studies of PM10 amounts on the surface of urban vegetation. Much less is known about PM in agricultural areas, although PM10 can be harmful to vegetation and, for food crops, have the potential to be ingested. Here we have quantified PM across the agricultural landscape of California, measuring the amounts present on the foliage of 18 crops at 21 locations. The amounts of particulates present varied (0.17–6.9 gm-2) and PM loads on leaves in the south and east of the area were higher than those in the northern and westerly locations. Our findings suggest that the amounts of particulates on the surface of agricultural crops can be high; exceeding the usual range of values for urban areas. Our data indicate that agricultural crops grown in regions like California and the Mediterranean where summer rainfall is largely absent and drip rather than spray irrigation is used are more vulnerable to PM accumulation and to any adverse effects resulting from these deposits. Microscopic analysis of PM10 on foliage showed that in these agricultural areas wind-blown soil particles make up 74.2% of the PM10 present; this is thus a very significant source. A small number of microplastic particles (2.2%) were also identified on foliage. We suggest that PM and microplastics could impact food and forage quality and that more work is needed to examine PM deposition to crops and their range of impacts.