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In order to study influence of automobile traffic on a local urban atmospheric environment, we have investigated suspended particulate matter (SPM) collected at sampling sites in a region which includes a major highway and a residential area in the southern part of Tokyo during August - November 1999. The atomic composition of each sample was measured by means of PIXE analysis using a 2.0 MeV proton beam. Sixteen elements were quantitatively measured. The positional dependence of SPM loading was determined for each element using samples simultaneously collected at three different sites. For the experimental results obtained for downwind conditions, the measured concentration as a function of the distance from the highway was compared with a simple calculation based on the Gaussian plume model. The concentration distribution of some heavy elements in the fine fraction is well reproduced by this analysis. It has been found that for ordinary moderate downwind conditions the area within 300-400 m from the highway is directly affected by emission due to the automobile traffic.

At certain locations in the Wellington Region, pollution episodes due to air particulate matter are known to occur from time to time. Traditional gravimetric analysis of airborne particulate matter is unable to provide information on the sources contributing to air particulate concentrations. Ion Beam Analysis (IBA) is one of the few non-destructive techniques that can be used to identify the elemental composition of air particulate matter on a filter sample. In this work IBA was used to characterise air particulate matter in two size fractions, PM_20. and PM_10-2.0, collected at a monitoring station in Masterton, New Zealand. Elements with atomic mass above neon were measured by the PIXE technique. Elemental carbon was measured with a light reflectance device. Elemental 'fingerprints' of contributing sources were determined by performing factor analysis of the elemental composition. The results indicate that 'Sea Salt' and 'Soil' sources are major contributors to the coarse (PM_10-2.0) fraction and 'Combustion' sources dominate the fine (PM_2.0) fraction of air particulate matter. Analysis of seasonal differences was a useful tool in elucidating source profiles.

Particulate matter (PM-3.9 and PM-15.8) samples were collected in the three zones at the Northeast, Southwest and Southeast suburbs of Mexico City, from July to August 1998, for one week for each sampling site. The concentrations of several elements in the PM-3.9 and PM-15.8 samples were determined by Particle Induced X-ray Emission (PIXE). In the PM-3.9 samples, 21 elements were determined for each zone, and Na, Mg, Al, Si, S, K, Ca, Ti, Fe, Cu, Zn and Pb are found to be the major elemental components. On the other hand, 22 elements including P were determined on the PM-15.8 samples, and the dominant elements were the same as in the PM-3.9. Factor analysis is applied to the 28 variables (14 elements for each PM-3.9 and PM-15.8 groups) and for 21 samples (seven days for three zones) in order to identify possible sources of the particles. The result of factor analysis allows to identify five major sources, being soil the major contributor.

Inhalation of fine particulate matter (${\text{PM}}_{2.5}$) is associated with elevated pulmonary injury caused by the loss of vascular barrier integrity. Black ginseng (BG), steamed and dried ginseng nine times, exhibits various pharmacological activities such as antibacterial, antihyperglycemic, anti-atopic, antibacterial, and anti-inflammatory activities. In this study, we investigated the beneficial effects of black ginseng extract (BGE) against PM-induced lung endothelial cell (EC) barrier disruption and pulmonary inflammation. Permeability, leukocyte migration, activation of proinflammatory proteins, generation of reactive oxygen species (ROS), and histology were examined in ${\text{PM}}_{2.5}$-treated ECs and mice. BGE significantly scavenged ${\text{PM}}_{2.5}$-induced ROS and inhibited the ROS-induced activation of p38 mitogen-activated protein kinase (MAPK). Concurrently, BGE activated Akt, which helped maintain endothelial integrity. Furthermore, BGE reduced vascular protein leakage, leukocyte infiltration, and proinflammatory cytokine release in the bronchoalveolar lavage fluid in PM-induced lung tissues. These results indicated that BGE may exhibit protective effects against PM-induced inflammatory lung injury and vascular hyperpermeability.

The temporal fluctuations of particulate matter time series of three reference European stations have been investigated, by using the power spectrum analysis. Our results point out to the presence in particulate matter of annual periodicities superimposed on a scaling behaviour with exponent ranging between ~1.4 and ~1.6, indicating quite high persistent correlations. Furthermore, a crossover timescale at about 1 month, evidenced in all the signals analysed, could be linked with chemical-physical processes in which aerosol particles are involved during their atmospheric lifetimes.

The cement industry constitutes a major source of air pollution and its environmental impacts have historically raised considerable public concern. This paper presents a health-based economic assessment of reducing particulate and sulfate emissions from a cement industrial complex. The economic valuation of the potential decrease in mortality and morbidity rates due to emissions reduction was conducted using a human capital approach and a cost of illness approach, respectively.

The objectives of this study were to assess potential health and productivity benefits for the year 2010 with five scenarios for reducing particulate matter (PM₁₀ and PM_2.5) air pollution in the cities of Osaka, Houston, Bangkok and Seoul. Assuming a uniform 10% decline in ambient PM levels, the preventible cases of: (1) premature mortality ranged from 35 in Houston to 379 in Seoul, (2) chronic bronchitis ranged from 95 in Houston to 1,631 in Seoul, (3) cardiovascular disease ranged from 68 in Houston to 818 in Seoul, (4) pneumonia ranged from 28 in Houston to 336 in Seoul, (5) asthma attacks ranged from 388 in Osaka to 96,876 in Seoul, and (6) acute bronchitis ranged from 186 in Houston to 2,973 in Seoul. The per million population central estimate of the purchasing power parity adjusted value of health and productivity benefits ranged from $25 million in Bangkok to $160 million in Osaka. There was a wide variability in measured PM₁₀ levels across cities. Percentages of active monitors reporting concentrations above 50 μg/m³ (annual average) or 150 μg/m³ (24-hour average) in 2001–2002 were 0% in Houston, 5% in Osaka, 33% in Bangkok and 92% in Seoul. Assuming a non-uniform reduction in PM only at concentration hotspots with levels above air quality standards, the number of preventible cases of mortality ranged from 0 in Houston to 1,104 in Seoul. The central estimate of total benefits ranged from $0 in Houston to $240 million in Seoul.

In our modern world, air pollution is a significantly increasing issue. Sofia, the capital city of Bulgaria, is one of the most polluted cities in Europe. It has been a long-standing issue, with pollution levels regularly exceeding the recommended limits set by the World Health Organization.

The main causes of pollution in Sofia include the burning of garbage for residential heating, and emissions from vehicles due to heavy traffic. These factors especially worsen the situation during winter because of low winds and temperature inversions. This can be incredibly harmful to the health of the residents, with long-term exposure causing lung infections or cancer and possibly leading to death.

In recent years, several steps have been taken by the municipality and the residents to address the issue, some of which have proven successful. However, there are still further efforts needed to be undertaken.

The inhalation of airborne particles can endanger the health of any human being. Natural fiber and natural fiber reinforced with natural matrix material are employed in this work to create an indoor air purifier. Various natural fiber and natural composite combinations are used to purify the interior environment by eliminating particulate matter of various sizes and volatile organic chemicals. An air purifier is created using four distinct natural fibers, including hemp, jute, silk cocoon, and coir fibers, as well as neem and aloe vera gel as natural filler materials. An air quality-monitoring instrument is used to validate the performance of the designed natural fiber/natural plant-based filler material-equipped air purifier. Particulate matter of various sizes and volatile organic compounds in the indoor environment are detected at various time intervals. The efficacy of the air purifier is afterward determined in human lungs of various ages utilizing health impact simulation studies. The current product is utilized to effectively purify indoor air by eliminating particulates and volatile organic chemicals.

Ultrafine particles (less than 0.10 μm in diameter) are ubiquitous in the atmosphere and possess unique physicochemical characteristics that may pose a potential health risk. To help elucidate the potential health risk, we measured respiratory dose of ultrafine particles (0.04, 0.06, 0.08 and 0.10 μm in diameter) in healthy young adults using a novel serial bolusdelivery method. Under normal breathing conditions (i.e. tidal volume of 500 ml and respiratory flow rate of 250 ml s⁻¹), bolus aerosols were delivered sequentially to a lung depth ranging from 50–500 ml in 50 ml increments and deposition was measured for each of ten equal-volume compartments.

Results show that regional deposition varies widely along the depth of the lung regardless of the particle sizes used. Peak deposition was found in the lung regions situated between 150 and 200 ml from the mouth. Sites of peak deposition shifted proximally with a decrease in particle size. Deposition dose per unit surface area was largest in the proximal lung regions and decreased rapidly with an increase in lung depth. Peak surface dose was 5–7 times greater than the average lung dose. The results indicate that local enhancement of dose occurs in normal lungs, and such a dose enhancement may play an important role in the potential health effects of ultrafine aerosols.

Many ultrafine particles comprised classically of low-toxicity, low-solubility materials such as carbon black and titanium dioxide have been found to have greater toxicity than larger, respirable particles made of the same material. The basis of the increased toxicity of the ultrafine form is not well understood and a programme of research has been carried out in Edinburgh on the toxicology of ultrafines aimed at understanding the mechanism. We used fine and ultrafine carbon black, TiO₂ and latex and showed that there was an approximately 10-fold increase in inflammation with the same mass of ultrafine compared with fine particles. Using latex particles in three sizes—64, 202 and 535 nm—revealed that the smallest particles (64 nm) were profoundly inflammogenic but that the 202 and 535 nm particles had much less activity, suggesting that the cut-off for ultrafine toxicity lies somewhere between 64 and 202 nm. Increased oxidative activity of the ultrafine particle surface was shown using the fluorescent molecule dichlorofluorescein confirming that oxidative stress is a likely process by which the ultrafines have their effects. However, studies with transition-metal chelators and soluble extracts showed that the oxidative stress of ultrafine carbon black is not necessarily due to transition metals. Changes in intracellular Ca²⁺ levels in macrophage-like cells after ultrafine particle exposure suggested one way by which ultrafines might have their pro-inflammogenic effects.

Extreme temperatures and high levels of air pollutants pose major risks to human health. Because heat waves and pollution episodes share common underlying drivers, they often coincide; additionally, they may worsen under future climate change and so it is extremely important to understand the extent of their co-occurrence so that proper mitigation and adaptation steps can be taken to minimize their impact. Here, we use 15 years of observations of temperature, and measurements of surface ozone and particulate matter (the two air pollutants with the greatest human health impact) to characterize the overlap of extreme pollution episodes and heat waves. We show that all three extremes occur in large-scale, multi-day, overlapping and coherent structures. Additionally, we find that the largest, longest lasting episodes have the greatest frequency of co-occurring extremes and have the highest temperatures and most extreme levels of pollution.

This removal of particulate matter (PM) and nitrogen oxides (NOx) by non-thermal plasma (NTP) assisted Ag/Al₂O₃ catalyst with propene (C₃H₆) is widely investigated. In this article, the method to remove PM and NOx using plasma with catalyst is feasible both in simulated and real diesel exhaust. The results indicated that the application of non-thermal plasma combined with catalyst decreases the PM incineration temperature of soots effectively, and the increasing catalytic reaction temperature results in improved catalytic efficiency. The effective temperature of C₃H₆ for SCR over Ag/Al₂O₃ is significantly in the range of 200-400℃, and thermal SCR is proved to be important for such processes above 400℃. In addition, the presence of H₂O did not decrease the efficiency of NOx removal above 350℃. The removal of PM and NOx are promoted by each other.