Levels Of Particulate Pollution Research Articles

The complex chemical effects of air pollutants, meteorology and dust on the concentrations of criteria and non-criteria air pollution in Kuwait

Air pollution is the leading environmental health risk factor globally. A number of cities experienced improvements in air quality during the COVID-19 lockdown; however such changes depend on the contributions from natural and anthropogenic sources and meteorological factors pertaining to each city. This study investigated the effects of anthropogenic and meteorological factors on air quality in Kuwait during the COVID-19 lockdown (22 March–10 May 2020) using mixed-effect regression and machine learning models. Criteria (PM2.5, PM10, NO2, O3, SO2, CO) and non-criteria (C6H6, NH3, H2S, NMHC) air pollutants were compared between the lockdown period, and the same period in the preceding and the following years, 2019 and 2021, respectively. The results showed that during the lockdown three criteria air pollutants (PM2.5, NO2, CO) were reduced by 38, 40, 26%, respectively. All no-criteria air pollutants were reduced, except for H2S. The arid region’s harsh desert conditions have major contributions to particulate pollution. Although PM levels are overwhelmed by meteorological and natural dust, stringent abatement measures on oil/gas hydrocarbon and power plant emissions can significantly reduce PM and other pollutants. Abatement measures on traffic pollution can further reduce the NO2 levels. This study highlights Kuwait's ongoing struggle with elevated levels of particulate and gaseous pollution, driven by hydrocarbon emissions and dust. Effectively tackling air quality requires a nuanced understanding of the interplay between air pollutants, meteorological, and dust covariates.

Enhanced Air Filtration Efficiency through Electrospun PVC/PVP/MWCNTs Nanofibers: Design, Optimization, and Performance Evaluation.

This study presents a novel approach for creating an effective air filtration medium using electrospun nanofibers comprised of poly(vinyl chloride) (PVC), poly(vinylpyrrolidone) (PVP), and impregnated with multiwall carbon nanotubes (MWCNTs). The membrane production was optimized using an experimental design methodology, resulting in a hydrophobic membrane that exhibits excellent dispersion of MWCNTs. Scanning electron microscopy images illustrate the nanofibers' morphology, featuring an average diameter of approximately 240 nm, minimal bead formation, and optimal MWCNT dispersion. Air filtration tests conducted with NaCl nanoparticles (7-300 nm) demonstrated superior permeability (10-12 m2) and minimal pressure drop (approximately 780 Pa at a 5 LPM airflow rate) compared to other electrospun materials. Both MWCNT-impregnated samples and individual PVC/PVP nanofibers exhibited filtration efficiencies nearing 96%. These results underscore the potential of this developed material for air filtration, particularly in indoor environments, where MWCNTs effectively adsorb and maintain low levels of gaseous and particulate pollutants. This study emphasizes the design, optimization, and comprehensive performance evaluation of PVC/PVP/MWCNT nanofibers, showcasing significant advancements in filtration efficiency with high flux. The findings suggest promising applications for this composite material in advanced air purification systems.

Drivers of PM2.5 Episodes and Exceedance in India: A Synthesis From the COALESCE Network

AbstractEmission sources influencing high particulate air pollution levels and related mortality in India have been studied earlier on country‐wide and sub‐national scales. Here, we use novel data sets of emissions (for 2019) and observations created under the Carbonaceous Aerosol Emissions, Source Apportionment, and Climate Impacts network in India (Venkataraman et al., 2020, https://doi.org/10.1175/bams‐d‐19‐0030.1) in WRF‐Chem simulations to evaluate drivers of high PM2.5 levels during episodes and in airsheds with different pollution levels. We identify airsheds in “extreme” (110–140 μg/m3), “severe” (80–110 μg/m3) and “significant” (40–80 μg/m3) exceedance of the Indian annual ambient air quality standard (National Ambient Air Quality Standards [NAAQS]) of 40 μg/m3 for PM2.5. We find that primary organic matter and anthropogenic mineral matter (largely coal fly‐ash) drive high PM2.5 levels, both annually and during high PM2.5 episodes. PM2.5 episodes are driven by organic aerosol in north India (Mohali) in wintertime but are additionally influenced by mineral matter and secondary inorganics in central (Bhopal), south India (Mysuru) and eastern India (Shyamnagar). Across airsheds in exceedance of the NAAQS and during high PM2.5 episodes, primary PM2.5 emissions arise largely from the residential sector (50%–75%). Formal sector emissions (industry, thermal power and transport; 40%–55%) drive airshed and episode scale PM2.5 exceedance in northern and eastern India. Agricultural residue burning emissions predominate (50%–75%) on episode scales, both in northern and central India, but not on annual scales. Interestingly, residential sector emissions strongly influence (60%–90%) airsheds in compliance with the NAAQS (annual mean PM2.5 < 40 μg/m3), implying the need for modern residential energy transitions for the reduction of ambient air pollution across India.

A Preliminary Case Study on the Compounding Effects of Local Emissions and Upstream Wildfires on Urban Air Pollution

Interactions between urban and wildfire pollution emissions are active areas of research, with numerous aircraft field campaigns and satellite analyses of wildfire pollution being conducted in recent years. Several studies have found that elevated ozone and particulate pollution levels are both generally associated with wildfire smoke in urban areas. We measured pollutant concentrations at two Utah Division of Air Quality regulatory air quality observation sites and a local hot spot (a COVID-19 testing site) within a 48 h period of increasing wildfire smoke impacts that occurred in Salt Lake City, UT (USA) between 20 and 22 August 2020. The wildfire plume, which passed through the study area during an elevated ozone period during the summer, resulted in increased criteria pollutant and greenhouse gas concentrations. Methane (CH4) and fine particulate matter (PM2.5) increased at comparable rates, and increased NOx led to more ozone. The nitrogen oxide/ozone (NOx/O3) cycle was clearly demonstrated throughout the study period, with NOx titration reducing nighttime ozone. These findings help to illustrate how the compounding effects of urban emissions and exceptional pollution events, such as wildfires, may pose substantial health risks. This preliminary case study supports conducting an expanded, longer-term study on the interactions of variable intensity wildfire smoke plumes on urban air pollution exposure, in addition to the subsequent need to inform health and risk policy in these complex systems.

Molecular-Level Insights into the Relationship between Volatility of Organic Aerosol Constituents and PM2.5 Air Pollution Levels: A Study with Ultrahigh-Resolution Mass Spectrometry.

Volatility of organic aerosols (OAs) significantly influences new particle formation and the occurrence of particulate air pollution. However, the relationship between the volatility of OA and the level of particulate air pollution (i.e., particulate matter concentration) is not well understood. In this study, we compared the chemical composition (identified by an ultrahigh-resolution Orbitrap mass spectrometer) and volatility (estimated based on a predeveloped parametrization method) of OAs in urban PM2.5 (particulate matter with aerodynamic diameter ≤ 2.5 μm) samples from seven German and Chinese cities, where the PM2.5 concentration ranged from a light (14 μg m-3) to heavy (319 μg m-3) pollution level. A large fraction (71-98%) of compounds in PM2.5 samples were attributable to intermediate-volatility organic compounds (IVOCs) and semivolatile organic compounds (SVOCs). The fraction of low-volatility organic compounds (LVOCs) and extremely low-volatility organic compounds (ELVOCs) decreased from clean (28%) to heavily polluted urban regions (2%), while that of IVOCs increased from 34 to 62%. We found that the average peak area-weighted volatility of organic compounds in different cities showed a logarithmic correlation with the average PM2.5 concentration, indicating that the volatility of urban OAs increases with the increase of air pollution level. Our results provide new insights into the relationship between OA volatility and PM pollution levels and deepen the understanding of urban air pollutant evolution.

Characterization of cross-continental PM2.5: Insights into emissions and chemical composition

Atmospheric fine particulate matter (PM2.5) is a critical indicator of air quality, with substantial implications for human health. Understanding the emission sources and chemical composition of PM2.5 is crucial for mitigating possible adverse health effects. This study spans five diverse cities on three continents from north and south hemisphere: Stockholm (Sweden), Kyoto (Japan), Limeira, Ribeirão Preto, and Cáceres (Brazil). Our objective was to assess PM2.5 chemical composition and regional and long-range transport influences to identify the main sources of particulate air pollution at these cities during the winter/dry seasons. All studied cities but Kyoto exhibited PM2.5 levels above World Health Organization (WHO) guidelines, with the Brazilian cities experiencing the highest fine particle pollution levels, implying increased adverse health risks. We observed significant variations in concentrations of polycyclic aromatic compounds (PACs), monosaccharide anhydrides (MAs), and inorganic elements. Limeira exhibited the highest levels of total PACs (median level of 12.4 ng m−3), while Cáceres displayed high variability of PACs, most likely due to episodic regional wildfire events. MA concentrations were significantly higher in Limeira and Ribeirão Preto and together with elevated levels of retene and potassium (K) they suggested a substantial influence of biomass burning. Backward air mass trajectory analysis suggested widespread Amazon and Savanna wildfires along with local fires as main contributors for these sites. All source identification approaches highlighted differences among the cities, with Stockholm and Kyoto showing influence of sources related to traffic emissions, waste burning, and long-range transport, and Brazilian cities traffic, industrial, biogenic, and more evident biomass burning. This cross-continental study provides valuable insights into PM2.5 composition and emission sources, emphasizing the impact of different emissions on air quality. Our findings underscore the importance of local strategies to mitigate air pollution and protect public health, especially in regions where PM2.5 levels consistently exceed recommended guidelines.

The Impact of Health Status and Experienced Disutility on Air Quality Valuation

This paper examines the impact of health status, and of experienced disutility caused by air pollution, on individuals' preferences regarding the health risk reductions resulting from air quality improvement. We investigate if changes in the level of experienced disutility due to air pollution mediate the relationship between individuals' respiratory health status and their preferences regarding health risk reductions. For this purpose, we conducted a choice experiment study among inhabitants of four big Polish cities that have varying levels of particulate matter pollution. We used the modified Medical Research Council breathlessness scale, verified in clinical trials, to obtain information about respondents’ health status, except for usually applied health status measures in stated preference surveys. We do not find any direct impact of health status (apart from smoking) on willingness to pay for air quality improvement. Our results indicate, however, that individuals who self-reported a respiratory diagnosis, as well as those who scored high on the breathlessness scale, are more likely to display a latent trait indicating experienced disutility due to air pollution, and that those who experience this disutility are, in general, more in favour of air quality improvement programmes.

Lung-depositing surface area (LDSA) of particles in office spaces around Europe: Size distributions, I/O-ratios and infiltration

Air pollution, and specifically particulate matter pollution, is one of the greatest dangers to human health. Outdoor air pollution ranks third in causes for premature death. Improving indoor air quality is of immense importance, as the time spent indoors is often much greater than the time spent outdoors. In this experimental study, we evaluate the levels of particle pollution in indoor air in four offices across Europe, compare the indoor particles to outdoor particles and assess where the particles originate from. The measurements were conducted with an Electrical Low-Pressure Impactor (ELPI+) for particles between 6 nm and 1 μm. The chosen metric, lung-deposited particle surface area (LDSA), targets the health impacts of particle pollution. Based on the measurements, we determined that most of the indoor air particles infiltrated from outdoor air, although two of the offices had very limited indoor activity during the measurement campaigns and may not represent typical use. The highest median indoor LDSA concentration during daytime hours was 27.2 μm2/cm3, whereas the lowest was 2.8 μm2/cm3. Indoor air in general had lower LDSA concentrations than outdoor air, the corresponding outdoor LDSA concentrations being 35.8 μm2/cm3 and 9.8 μm2/cm3. The particle size ranges which contributed to the highest concentrations were 50–100 nm and 300–500 nm. These size ranges correspond to soot mode and accumulation mode particles, which represent local and regional sources, respectively. Based on this study, limiting particle infiltration is the key factor in keeping indoor air in offices free of lung-depositing particles.

A Diffusion-Inertia Model for the simulation of particulate pollutants dynamics inside a car cabin

Simulations of particle pollutants dynamics inside a car cabin were performed using the Diffusion-Inertia Model (DIM) coupled to the RANS (Reynolds-averaged Navier–Stokes equations) k−ω SST turbulence model for single-phase flow. The DIM model has been implemented in a commercial CFD solver and then validated on some reference flow configurations. The validation included particle dispersion in ventilated chambers of one and two compartments, particle deposition in circular 90°bends, and particle-laden jet flow. The DIM model has shown interesting capabilities in taking into account various transport mechanisms such as the transport by the mean flow, gravitational settling, centrifugal effect due to flow streamline curvatures, molecular and turbulent diffusion, and also turbophoresis transport mechanism due to turbulent energy gradients. Moreover, the application of the DIM model to the simulation of solid particles, characterizing particulate pollutants, has revealed characteristic dynamics that is mainly determined by the airflow topology, particularly for ultrafine and fine particles (0.1, 1 and 2.5μm). Inertial effects were found to become significant only for coarse particles (5 and 10μm), as the impact of gravitational and centrifugal effects gradually becomes more noticeable. Furthermore, the risk of exposure to high levels of particulate pollutants has been clearly established when considering the presence of occupants inside the vehicle cabin. These concentration levels are linked in particular to the complex interaction between occupants’ heads and the internal flow, as well as to the tendency of particles to accumulate in the upper part of the cabin and to the rapid homogenization observed throughout the whole interior volume.

Estimating Air Pollution in Operation Rooms Generated from Cautery, Drills, and Other Equipment, Utilizing a Particulate Counter and Gas Analyzer.

Air pollution, especially indoor air pollution, is increasingly recognized as a worldwide hazard that reduces life expectancy. Pollution caused by equipment such as surgical cautery is not just a nuisance but a workplace hazard that exposes the staff to respirable particulate matter and toxic chemical agents. It has not yet received much recognition in India, nor have mitigating measures like smoke evacuators and dedicated scavenging systems become prevalent. We aimed to do a prospective observational study of the extent of this hazard in the operation rooms in our tertiary care, Government-run hospital using a consumer-grade pollution measuring equipment (CAIR +™, Prana Air, New Delhi). We measured and compared the particulate pollutant matter (PM) levels, Total Volatile Organic Compounds (TVOC), formaldehyde, and carbon dioxide at multiple areas of interest at different time points. The particulate pollution level in PM 1.0, PM 2.5, and PM 10 and TVOCs rose many times the baseline near the surgical team during cautery use. It remained high near the anesthesia workstation. The median PM 2.5 level in µg/m3(micrograms/cubic meter) was 181 near the surgical team during cautery use, and it was 25 at the anesthesia workstation. This peak level was 30 times the basal level of 6 µg/m3 at the start of the day and was above the annual population-weighted mean PM 2·5 breakpoint of 40 μg/m3 recommended by the National Ambient Air Quality Standards in India. The pollution levels increase dramatically when surgical cautery is used, potentially exposing the team to large peak elevations in particulate matter and TVOCs. We recommend the mandatory use of smoke evacuators and optimization of the air conditioning.

Investigation of the nanometal levels in the atmosphere of Chakan high tech industrial Park, Chakan (MH), India

Nanometals contained in airborne particles pose a public health risk since they can enter people's respiratory systems and cause lung damage. In general, air pollution is defined as any substance that has been discharged into the atmosphere and has the potential to seriously harm both the environment and living creatures. The current study was conducted in India's Chakan High Tech Industrial Area, which is affected by various industries, such as automotive, electric, power, and iron smelting, which may contribute to environmental air pollution. Sampling of PM2.5 was carried out by high-volume samplers with cascade impactors over two year (2021 and 2022) at two separate locations, one in an industrial park and the other in a residential area. The heavy metals linked to the particulate matter were identified using inductive coupled plasma optical emission spectrometry (ICP-OES). Results revealed that the industrial park had higher levels of particle pollution than the residential neighborhood of Chakan. The primary sources of toxic metal emissions into the atmosphere are industrial and commercial activity. Thankfully, none of the nanometals' concentrations exceeded the limits set by the World Health Organization (WHO) and India's Air (P&CP) Act of 1981. This study was conducted to help identify and measure the concentration of nanometals in air, with the aim of protecting both the environment and living beings from potential harm. Further research will be needed to protect people from the numerous diseases, respiratory conditions, and other health issues brought on by exposure to air pollution in this region.

Laboratory and field evaluation of a low-cost optical particle sizer

Low-cost sensors are widely used to collect high-spatial-resolution particulate matter data that traditional reference monitoring devices cannot. In addition to the mass concentration, the number concentration and size distribution are also fundamental in determining the origin and hazard level of particulate pollution. Therefore, low-cost optical sensors have been improved to establish optical particle sizers (OPSs). In this study, a low-cost OPS, the Nova SDS029, is introduced, and it is evaluated in comparison to two reference instruments—the GRIMM 11-D and the TSI 3330. We first tested the sizing accuracy using polystyrene latex spheres. Then, we assessed the mass and number size distribution accuracy in three application scenarios: indoor smoking, ambient air quality, and mobile monitoring. The evaluations suggest that the low-cost SDS029 rivals research-grade optical sizers in many aspects. For example, (1) the particle diameters obtained with the SDS029 are close to the reference instruments (usually < 10%) in the 0.3–5 µm range; (2) the number of particles and mass concentration are highly correlated (r ≥ 0.99) with the values obtained with the reference instruments; and (3) the SDS029 slightly underestimates the number concentration, but the derived PM2.5 values are closer to monitoring station than the reference instruments. The successful application of the SDS029 in multiple scenarios suggests that a plausible particle size distribution can be obtained in an easy and cost-efficient way. We believe that low-cost OPSs will increasingly be used to map the sources and risk levels of particles at the city scale.

The concentration of particulate matter in the barn air and its influence on the content of heavy metals in milk

Heavy metals are one of the components of smog, which is mainly the product of burning fossil fuels in residential buildings. These elements, introduced into the body of cattle by inhalation, may enter the milk. The goal of this study was to assess the impact of particulate pollution in the atmospheric air on the concentration of particulate matter in the air of a dairy cattle barn and on the content of selected heavy metals in milk from cows present in the building. Measurements were taken between November and April (148 measurement days). The calculations carried out showed a high correlation (RS = + 0.95) between the concentrations of particulates measured outside and inside the barn, which is indicative of a significant impact of the atmospheric air on the particulate pollution level of the livestock building. The number of days in excess of the daily standard for PM10 inside was 51. The conducted analysis of the chemical composition of the milk collected under high particulate pollution (February) showed that the permitted lead level had been exceeded—21.93 µg/kg (norm 20.00 µg/kg).

A Community-Based Sensor Network for Monitoring the Air Quality in Urban Romania

Air quality, especially particulate matter pollution levels in urban areas, is an essential academic and social topic due to its association with health issues and climate change. In Romania, increasing awareness of urban communities and the availability of low-cost sensors has led to the development of an independent monitoring network currently distributed in over 194 cities and towns. The uRADMonitor® network consists of 630 sensors measuring PM10 and PM2.5 concentration levels. The spatial distribution of the sensors complements the national air quality network with sensors in residential areas, intense traffic zones, and industrial areas. The data are available through a user-friendly web-based platform from uRADMonitor®. Based on data collected in 2021, we present an analysis of PM10 pollution levels in Romania’s five most populated urban areas by employing five annual statistical indicators recommended by the European Environmental Agency. For the case of Timișoara, we also compare the data measured by independent sensors with those from the national monitoring network. The results highlight the usefulness of our community-based network as it complements the national one.

Excess Global Blood Pressure Associated With Fine Particulate Matter Air Pollution Levels Exceeding World Health Organization Guidelines

Excess Global Blood Pressure Associated With Fine Particulate Matter Air Pollution Levels Exceeding World Health Organization Guidelines

Low-grade malt lymphoma of the nasopharynx in young adults: Successful treatment of a rare diagnosis at a rare site by radiotherapy.

Mucosa Associated Lymphoid Tissue (MALT) lymphoma is the third most common subgroup of Non-Hodgkin's lymphoma and is the most common type of primary extranodal lymphoma. They are rarely found in the nasopharyngeal region and their mean age at presentation is the sixth decade of life. We present the clinical, pathological, treatment and 5-year follow-up data of 5 cases of nasopharyngeal MALT lymphoma treated with definitive radiotherapy at our hospital, between 2009 and 2011. The average age of diagnosis was 27 years which is more than a decade earlier than what has been reported previously. Clinical symptoms included nasal obstruction, tinnitus and hearing loss. All five patients had locoregional disease. They were treated by definitive radiotherapy to a dose between 30 to 40 Gy. At 5 years of follow-up, 4 patients were in complete remission while one had disease relapse. The younger age of presentation compared to older reports in this rare subsite was an interesting finding in our study. The authors speculate that rising levels of particulate air pollution may have played a part in the etiology in this younger population. Our series shows that despite the younger age, the disease displays an indolent course and responds well to radiotherapy alone as the primary treatment. Recurrence or disseminated disease is also highly treatable with systemic chemotherapy.

Particulate Levels Underneath Landscape Fire Smoke Plumes in the Sydney Region of Australia

Smoke pollution from landscape fires is a major health problem, but it is difficult to predict the impact of any particular fire. For example, smoke plumes can be mapped using remote sensing, but we do not know how the smoke is distributed in the air-column. Prescribed burning involves the deliberate introduction of smoke to human communities but the amount, composition, and distribution of the pollution may be different to wildfires. We examined whether mapped plumes produced high levels of particulate pollution (PM2.5) at permanent air quality monitors and factors that influenced those levels. We mapped 1237 plumes, all those observed in 17 years of MODIS imagery over New South Wales, Australia, but this was only ~20% of known fires. Prescribed burn plumes tended to occur over more populated areas than wildfires. Only 18% of wildfire plumes and 4% of prescribed burn plumes passed over a monitor (n = 115). A minority of plumes caused a detectable increase in PM2.5: prescribed burn plumes caused an air quality exceedance for 33% of observations in the daytime and 11% at night, wildfire plumes caused exceedances for 48% and 22% of observations in the day and night-time, respectively. Thus, most plumes remained aloft (did not reach the surface). Statistical modelling revealed that wind speed, temperature, and mixing height influenced whether a plume caused an exceedance, and there was a difference between prescribed and wild fires. In particular, in wind speeds below 1 kmhr−1, exceedance was almost certain in prescribed burns. This information will be useful for planning prescribed burning, preparing warnings, and improving our ability to predict smoke impacts.

Increased night-time oxidation over China despite widespread decrease across the globe

Nitrogen oxides (NOx = NO + NO2) emitted from combustion and natural sources are reactive gases that regulate the composition of Earth’s atmosphere. Nocturnal oxidation driven by nitrate radicals is an important but poorly understood process in atmospheric chemistry, affecting the lifetimes of NOx and ozone and particulate pollution levels. Understanding the trends of nitrate radicals is important to formulating effective pollution mitigation strategies and understanding the influence of NOx on climate. Here we analyse publicly available monitoring data on NOx and ozone to assess production rates and trends of surface nitrate radicals from 2014 to 2021 across the globe. We show that nitrate radicals have undergone strong increases in China during 2014–2019 but exhibited modest decreases in the United States and the European Union. Accelerated night-time oxidation has shortened the lifetime of summer NOx in China by 30% during 2014–2019. This change will strongly affect ozone formation and has policy implications for the joint control of ozone and fine particulate pollution. Measurements show that night-time production of atmospheric nitrate radicals increased in China but decreased in the European Union and the United States from 2014 to 2019. This suggests the increasing contribution of night-time atmospheric oxidation in China to air pollution.

Atmospheric goals for sustainable development

Atmospheric chemistry and composition underlie the existential threats of climate change and ozone depletion (1), and poor air quality represents the greatest environmental health issue in the modern world (2). However, the only targets and indicators related to atmospheric health and clean air in the United Nations Sustainable Development Goals (SDGs) focus on reducing fine particulate pollution levels and the associated mortality rates (3, 4). By creating targets for a broad range of specific pollutants, the SDGs could facilitate more effective actions, monitoring, and funding.

Effects of Pollution on Pregnancy and Infants.

The fetus is particularly susceptible to environmental contaminants as it is developing at the time of pregnancy and is, therefore, more susceptible to their effects. Pregnancy loss, which includes stillbirth and spontaneous abortion (miscarriage), preterm labor and delivery, and neonatal death, is the worst pregnancy outcome. Stunting and its related health and developmental effects are particularly common in populations living in underdeveloped countries or those exposed to high levels of particle pollution. Several environmental toxins can affect an embryo, fetus, or infant as they are developing. This study explores the following questions: What part do pesticides, heavy metals, dioxin derivatives, and polychlorinated diphenyl compounds play as macroenvironmental pollutants in mutagenesis and teratogenesis? What effects do substances that exposed persons have considerable control over, such as alcohol, narcotics, and tobacco smoke, have on the microenvironment? What consequences should practitioners be aware of these toxins in terms of ethics and the law? This study seeks to assess pertinent primary scientific studies on how pollution affects the health of the fetus and newborn during pregnancy.