Composition Of Airborne Particulate Matter Research Articles

Job function as determinant of clinker exposure at workplaces during cement production.

In the cement production industry, exposure to airborne particulate matter is associated with a decline in lung function and increased airway symptoms. Exposure to clinker-the major constituent of cement and supposedly the cause of the observed adverse health effects-was determined recently in 15 cement production plants located in 8 different countries (Estonia, Greece, Italy, Norway, Sweden, Switzerland, Spain, Turkey). It was shown that the median clinker abundance in the thoracic fraction varied between approximately 20% and 70% for individual plants. The present study complements the previous work by investigating the significance of job function as a determinant of clinker exposure. The elemental composition (water and acid-soluble fractions separately) of 1,227 personal thoracic workplace samples was analyzed by positive matrix factorization (PMF) to determine the contribution of different sources to the composition of airborne particulate matter and to quantify the clinker content. Median thoracic mass air concentrations varied for individual job functions between 0.094 and 12mg/m3 (estimated separately for different plants). The PMF 5-factor solution yielded median relative clinker abundances in the personal thoracic samples between 7.6% and 81% for individual job functions. Thoracic clinker air concentrations are highest for cleaning, production, and maintenance work, and lowest for administration and other work. Foremen and laboratory personnel show intermediate exposure levels. The plant was found to have a much higher contribution to the total variance of the thoracic clinker air concentrations than the job function. Thoracic clinker air concentrations (medians between 0.01 and 5.5mg/m3) are strongly correlated with the thoracic mass air concentrations and to a lesser extent with the relative clinker abundance in an aerosol sample. Job function is an important predictor of exposure to clinker in the cement production industry. As clinker is suspected to be the causal agent for the observed adverse health effects among cement production workers, the clinker air concentration may be a better exposure metric than thoracic air mass concentration despite the strong correlation between the two. Reduction strategies should focus on the most exposed job categories cleaning, production, and maintenance work.

Size distribution and elemental composition of airborne particulate matter on four plant species in vertical greenery systems

Vertical greenery systems (VGSs) have been proven to greatly improve the urban thermal environment. However, their effect on the retention of airborne particulate matter (PM) in the road environment remains unclear. This study aimed to assess the quantity of size-segregated PMs on both the upper (adaxial) and lower (abaxial) leaf surfaces, the mass of size-segregated PMs on the leaf surface and within the leaf wax, as well as the elemental composition of PMs retained in leaf stomata of four plant species in VGSs in Guangzhou. The findings revealed that VGSs exhibited greater retention of fine (<2.5 μm) PMs when compared to coarse (2.5–10 μm) and large (>10 μm) PMs. Among the four species studied, Tradescantia spathacea exhibited the highest PM retention in VGSs. The number density of accumulated PMs on the upper and lower leaf surfaces of the four plant species of VGSs at three heights varied significantly with species, heights, and their interaction (P < 0.05). The greatest stomatal block rate by PM occurred at a height of 0.6 m, the range was 91.1%–98.0%. The composition of PMs retained by the leaves primarily consisted of common element of C, O, Ca, K, Mg, and Si, which likely originated from natural sources. Heavy metals (HMs) such as Cr and Cd may have originated from brakes, while Zn and Cu might be attributed to tire wear and exhaust emissions. Therefore, VGSs effectively retained a substantial quantity of airborne PM and contributed to the mitigation of urban air pollution issues.

Elemental composition of airborne particulate matter from coastal South Florida area influenced by African dust events

• The elements Pb, Zn, V, Ni, Cd, As, Cr, and Cu presented the highest EFs. • As, Ni, Cd and Pb levels were below the maximum levels set by EU and USEPA. • REE were used to identify African dust contributions to the local APM. • The oil-fired Port Everglades Power Plant played an important role in the APM. • Road dust and waste incineration emissions were the second APM source of importance. Airborne particulate matter (APM) is a complex mixture of dust, dirt, soot and smoke containing both organic and inorganic components as well as biological particles. APM below 10 µm can enter the respiratory track and are known to cause adverse health effects. African dust storms are responsible for the transport of large amount of APM across the Atlantic Ocean during summer months. Anthropogenic activities are also responsible for APM pollution contribution in coastal areas and could have potential effects on sensitive ecosystems. The present study evaluates the elemental composition of APM collected from a coastal area in South Florida. In this study, a high-volume air sampler equipped with Versapor filters and located near the Port of Fort Lauderdale was employed for APM collection from 2005 to 2010. APM chemical composition was analyzed for multiple elements by ICP-MS. Seven of the eleven metals listed by the EPA as hazardous air pollutants (Mn, Cd, Cr, Ni, Pb, As, Co and Se) were detected in the samples. Iron and aluminum were the most abundant elements found in all samples, followed by V and Ni, which are usually associated with anthropogenic pollution coming from fossil fuel combustion. Specific sources of APM pollution were identified by principal component analysis and using the U.S. EPA UNMIX model for environmental data analyses. Rare earth elements were used to identify contributions of geological material to the APM and African dust influence during the summer months.

Method for Preparation of a Candidate Reference Material of PM10 and PM2.5 Airborne Particulate Filters Loaded with Incineration Ash-Inter Comparison Results for Metal Concentrations

Air pollution is an important issue that can have significant implications for human health. Consequently, air quality control is matter of great interest, and the ΕU has established strict legislation with respect to public health protection. A work package of the EMPIR project AEROMET focused on the investigation of traceable validated methods for chemical composition of airborne particulate matter (PM), including heavy metals. Incineration ash typically contains quantities of heavy and toxic metals in excess of the limits imposed for airborne PM, so it provides a candidate source for a Standard Reference Material (SRM). In this work, a method for loading incinerator ash (PM10 and PM2.5 fractions) on quartz filters with a good reproducibility and homogeneity was developed. An intercomparison exercise involving three separate laboratories was conducted for the elemental analysis of the prepared candidate reference material. The filters were treated by acid digestion and analyzed by Inductively Coupled Plasma–Mass Spectrometry (ICP-MS) according to the European standard EN 14902:2005. Eleven elements, including the regulated metals (As, Cd, Ni and Pb), were determined using different ICP-MS instruments and standardization methods. Data evaluation showed a good agreement between the results, with deviations below 10–15%. The development of a Standard Reference Material seems auspicious.

Elemental composition and source apportionment of atmospheric aerosols collected from urban and residential areas of Jordan using multi-secondary targets energy dispersive X-ray fluorescence

In the present work, the elemental composition of airborne particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5) collected from urban and residential areas of Jordan was determined and the associated pollution sources were identified. The sampling was performed in sites located in Zarqa and Amman during the winter and spring seasons of 2014/2015. The quantitative elemental analysis of nineteen (19) elements was carried out using an energy dispersive X-ray fluorescence (EDXRF) spectrometer utilizing the polarization geometry and the three secondary targets (CaF2, Ge and Mo). Remarkable enhancement in terms of analytical range, low Z-elements quantification (including Al, Na and Cl), and limits of detection were achieved. The total concentration of the PM2.5 samples in winter is higher than its concentration during spring due to the lower dispersion of atmospheric aerosols. Despite the lower concentration of PM2.5 collected from the urban location, Zarqa, high concentrations of the elements Ca, V, Cu, Zn and Pb were recognized which could be an indication to the industrial and anthropogenic activities at Zarqa. The average concentration of Ca in the urban area is approximately twice the concentration in the residential site which indicates the heavy cement industries at Zarqa city. A similar concentration of S was found in both locations which indicates the same anthropogenic sources such as consuming fuels and electrical power plants. The average percentages of the total detected elements at Amman and Zarqa are equal to 48% and 86% from the total mass concentration, respectively, which confirm the heavy anthropogenic activities at Zarqa. Based on the calculations of Pearson's correlation coefficients and the principle component analysis, source apportionments of the detected elements in the two locations were evaluated.

Microbiome composition of airborne particulate matter from livestock farms and their effect on innate immune receptors and cells

Patients with respiratory diseases in rural areas have been reported to have enhanced responsiveness to ambient particulate matter (PM). In addition to the physical and chemical components, ambient PM can contain microorganisms or parts thereof, referred here as BioPM, that can also contribute to the adverse health effects. This study aimed to characterize the microbial composition of BioPM originating from livestock, and to investigate whether these BioPM can trigger the activation of innate receptors and cells. Coarse (PM2.5–10 μm) and fine (PM<2.5 μm) BioPM samples were collected from indoor chicken, pig and goat farms using the versatile aerosol concentration enrichment system (VACES) connected to a Biosampler. The fungal and bacterial communities were assessed with an amplicon based approach using Next Generation Sequencing (NGS). In parallel, HEK-Blue cells expressing different pattern recognition receptors (Toll like receptors (TLR) 2, 3, 4, 5, 7, 8, 9 and NOD 1, 2) and a human monocytic cell line (MM6) were exposed to BioPM samples from these sites. Distinct airborne microbiota profiles associated with the corresponding animal farm were observed. Moreover, the various BioPM contained mainly ligands for TLR2 and TLR4 resulting in a concentration-dependent increase of pro-inflammatory cytokine secreted by MM6 cells. In addition, we show for the first time that only the pig-derived BioPM induced TLR5 activation. These findings suggest that animal farm specific BioPM trigger distinct inflammatory responses, which may contribute to airway diseases in humans.

An ultra-spatially resolved method to quali-quantitative monitor particulate matter in urban environment.

Monitoring the amount and composition of airborne particulate matter (PM) in the urban environment is a crucial aspect to guarantee citizen health. To focus the action of stakeholders in limiting air pollution, fast and highly spatially resolved methods for monitoring PM are required. Recently, the trees' capability in capturing PM inspired the development of several methods intended to use trees as biomonitors; this results in the potential of having an ultra-spatially resolved network of low-cost PM monitoring stations throughout cities, without the needing of on-site stations. Within this context, we propose a fast and reliable method to qualitatively and quantitatively characterize the PM present in urban air based on the analysis of tree leaves by scanning electron microscopy combined with X-ray spectroscopy (SEM/EDX). We have tested our method in the Real Bosco di Capodimonte urban park (Naples, Italy), by collecting leaves from Quercus ilex trees along transects parallel to the main wind directions. The coarse (PM10-2.5) and fine (PM2.5) amounts obtained per unit leaf area have been validated by weighting the PM washed from leaves belonging to the same sample sets. PM size distribution and elemental composition match appropriately with the known pollution sources in the sample sites (i.e., traffic and marine aerosol). The proposed methodology will then allow the use of the urban forest as an ultra-spatially resolved PM monitoring network, also supporting the work of urban green planners and stakeholders.

Urban influence on the concentration and composition of submicron particulate matter in central Amazonia

Abstract. An understanding of how anthropogenic emissions affect the concentrations and composition of airborne particulate matter (PM) is fundamental to quantifying the influence of human activities on climate and air quality. The central Amazon Basin, especially around the city of Manaus, Brazil, has experienced rapid changes in the past decades due to ongoing urbanization. Herein, changes in the concentration and composition of submicron PM due to pollution downwind of the Manaus metropolitan region are reported as part of the GoAmazon2014/5 experiment. A high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a suite of other gas- and particle-phase instruments were deployed at the “T3” research site, 70 km downwind of Manaus, during the wet season. At this site, organic components represented 79±7 % of the non-refractory PM1 mass concentration on average, which was in the same range as several upwind sites. However, the organic PM1 was considerably more oxidized at T3 compared to upwind measurements. Positive-matrix factorization (PMF) was applied to the time series of organic mass spectra collected at the T3 site, yielding three factors representing secondary processes (73±15 % of total organic mass concentration) and three factors representing primary anthropogenic emissions (27±15 %). Fuzzy c-means clustering (FCM) was applied to the afternoon time series of concentrations of NOy, ozone, total particle number, black carbon, and sulfate. Four clusters were identified and characterized by distinct air mass origins and particle compositions. Two clusters, Bkgd-1 and Bkgd-2, were associated with background conditions. Bkgd-1 appeared to represent near-field atmospheric PM production and oxidation of a day or less. Bkgd-2 appeared to represent material transported and oxidized for two or more days, often with out-of-basin contributions. Two other clusters, Pol-1 and Pol-2, represented the Manaus influence, one apparently associated with the northern region of Manaus and the other with the southern region of the city. A composite of the PMF and FCM analyses provided insights into the anthropogenic effects on PM concentration and composition. The increase in mass concentration of submicron PM ranged from 25 % to 200 % under polluted compared with background conditions, including contributions from both primary and secondary PM. Furthermore, a comparison of PMF factor loadings for different clusters suggested a shift in the pathways of PM production under polluted conditions. Nitrogen oxides may have played a critical role in these shifts. Increased concentrations of nitrogen oxides can shift pathways of PM production from HO2-dominant to NO-dominant as well as increase the concentrations of oxidants in the atmosphere. Consequently, the oxidation of biogenic and anthropogenic precursor gases as well as the oxidative processing of preexisting atmospheric PM can be accelerated. This combined set of results demonstrates the susceptibility of atmospheric chemistry, air quality, and associated climate forcing to anthropogenic perturbations over tropical forests.

Field and laboratory evaluation of a high time resolution x-ray fluorescence instrument for determining the elemental composition of ambient aerosols

Abstract. Measuring the chemical composition of airborne particulate matter (PM) can provide valuable information on the concentration of regulated toxic metals, support modelling approaches for source detection and assist in the identification and validation of abatement techniques. Undertaking these at a high time resolution (1 h or less) enables receptor modelling techniques to be more robustly linked to emission processes. This study describes a comprehensive laboratory and field evaluation of a high time resolution x-ray fluorescence (XRF) instrument (CES XACT 625) for a range of elements (As, Ba, Ca, Cd, Ce, Cl, Cr, Cu, Fe, K, Mn, Mo, Ni, Pb, Pt, S, Sb, Se, Si, Sr, Ti, V and Zn) against alternative techniques: high time resolution mass measurements, high time resolution ion chromatography, aerosol mass spectrometry, and established filter-based, laboratory analysis using inductively coupled plasma mass spectrometry (ICP-MS). Laboratory evaluation was carried out using a novel mass-based calibration technique to independently assess the accuracy of the XRF against laboratory generated aerosols, which resulted in slopes that were not significantly different from unity. This demonstrated that generated particles can serve as an alternative calibration method for this instrument.The XACT was evaluated in three contrasting field deployments; a heavily trafficked roadside site (PM10 and PM2.5), an industrial location downwind of a nickel refinery (PM10) and an urban background location influenced by nearby industries and motorways (PM10). The XRF technique agreed well with the ICP-MS measurements of daily filter samples in all cases with a median R2 of 0.93 and a median slope of 1.07 for the elements As, Ba, Ca, Cr, Cu, Fe, K, Mn, Ni, Pb, Se, Sr, Ti, V and Zn. Differences in the results were attributed to a combination of inlet location and sampling temperature, variable blank levels in filter paper and recovery rates from acid digestion. The XRF technique also agreed well with the other high time resolution measurements but showed a clear positive difference (slopes between 1.41 and 4.6), probably due to differences in the size selection methodology, volatility and water solubility of the PM in aerosol mass spectrometry (SO4) and ion chromatography (Ca, Cl, K and SO4), respectively.A novel filter analysis technique using the XACT showed promising initial results: filters analysed off-line with the XACT compared well to in situ XACT measurements with a median R2 of 0.96 and median slope of 1.07. The resulting range of slopes was comparable to slopes produced in the ICP-MS comparison. This technique provides an opportunity to use the XACT when it is not deployed in the field; thus expanding the potential use of this instrument in future studies.

Coarse particulate matter (PM2.5\u201310) in Los Angeles Basin air induces expression of inflammation and cancer biomarkers in rat brains

Air pollution is linked to brain inflammation, which accelerates tumorigenesis and neurodegeneration. The molecular mechanisms that connect air pollution with brain pathology are largely unknown but seem to depend on the chemical composition of airborne particulate matter (PM). We sourced ambient PM from Riverside, California, and selectively exposed rats to coarse (PM2.5–10: 2.5–10 µm), fine (PM<2.5: <2.5 µm), or ultrafine particles (UFPM: <0.15 µm). We characterized each PM type via atomic emission spectroscopy and detected nickel, cobalt and zinc within them. We then exposed rats separately to each PM type for short (2 weeks), intermediate (1–3 months) and long durations (1 year). All three metals accumulated in rat brains during intermediate-length PM exposures. Via RNAseq analysis we then determined that intermediate-length PM2.5–10 exposures triggered the expression of the early growth response gene 2 (EGR2), genes encoding inflammatory cytokine pathways (IL13-Rα1 and IL-16) and the oncogene RAC1. Gene upregulation occurred only in brains of rats exposed to PM2.5–10 and correlated with cerebral nickel accumulation. We hypothesize that the expression of inflammation and oncogenesis-related genes is triggered by the combinatorial exposure to certain metals and toxins in Los Angeles Basin PM2.5–10.

Characterization of Urban Atmospheric PM2.5 by ATR-FTIR, ICP-MS and SEM-EDS Techniques

The study aims to investigate the chemical composition of airborne particulate matter with size below 2.5 �m (PM2.5) collected from Targoviste City area, in the summer of 2015. For this consideration eleven representative points have been chosen for sampling. This research provides interesting data which can clarify the relationship between PM2.5 exposure and the negative effects on human health at urban area level. Three analytical techniques have been developed for the qualitative, quantitative and morphological characterization of PM2.5. The inorganic and organic functional groups of the PM2.5 samples were investigated by Attenuated Total Reflectance - Fourier Transform Infrared Spectrometry (ATR-FTIR). The content of several elements (i.e. Pb, Cd, Cr, Ni, Cu, Mn, Al, Zn and Fe) in samples was determined by Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). The measured concentration of these metals was compared with values reported by the International Agency on urban area in order to establish the minimal element level which cannot be considered as a potential health risk for the urban population. The morphological characterization of PM2.5 was performed by Scanning Electron Microscopy - Energy Dispersive Spectrometry (SEM-EDS). The elemental analysis of samples were performed by EDS and showed that airborne particle was mainly composed of elements, such as C, O, Si, Ca, N and S.

Composition of airborne particulate matter in the industrial area versus mountain area

The paper deals with research of air pollution in two different locations on the Moravian-Silesian Region, Czech Republic. These are the sites Ostrava-Radvanice, which is located in the area affected by the industry and Ostravice in the mountains (without significant effect of the industry). The dust particles collected at these locations were subjected to a wide range of analyses. The mass concentration, the mass-size distribution, mineralogical composition, the concentration of PAHs (polycyclic aromatic hydrocarbons), and the concentrations of selected metals (Cd, Pb, Zn, Fe, Mn, As, Ni, Co, and Cr) were observed at the particulate matter.

Sampling and composition of airborne particulate matter (PM10) from two locations of Mexico City.

The PM10 airborne particulate matter with an aerodynamic diameter ≤10 µm is considered as a risk factor of various adverse health outcomes, including lung cancer. Here we described the sampling and composition of PM10 collected from an industrial zone (IZ), and a commercial zone (CZ) of Mexico City. The PM10 was collected with a high-volume sampler in the above mentioned locations and both types of PM10 sampled were characterized by the content of polycyclic aromatic hydrocarbons (PAHs), metals, and endotoxin. The endotoxin PM10 content from IZ and CZ displayed 138.4 UE/mg and 170.4 UE/mg of PM10, respectively.

The effect of a fireworks event on the amount and elemental concentration of deposited dust collected in the city of Debrecen, Hungary.

Many social celebrations in urban areas are followed by fireworks show. The organic and inorganic pollutants emitted during detonations are expected to affect the ambient air quality of these celebration sites. The environmental aspects of fireworks events are usually investigated by analyzing the concentration and composition of airborne particulate matter, while there is limited information regarding the effect of fireworks on the elemental concentration of deposited dust. In this study, foliage dust samples were collected in the city of Debrecen (Hungary) before and after the fireworks show, organized on the 20th of August for the celebration of a historical event. Leaf samples (Tilia tomentosa) were collected around the location of the area of festivities. The sampling sites were further divided into five areas: city center (center), Southeast (SE), Southwest (SW), Northeast (NE), and Northwest (NW). We found that the amount of deposited dust particles increased significantly after the fireworks show compared to the background; we also found significant differences in the amount of dust deposition between the different locations of the city. A statistically higher level of Ca, Mg, and Sr was detected in samples collected after the display compared to those collected during the previous days, while the concentration of other studied elements were not statistically different from the background level. Our study confirmed previous findings that the relatively high altitude of detonations allows chemicals to disperse in the fine and ultrafine aerosol fractions; thus, the emitted pollutants by fireworks shows do not increase the level of elements as markedly in deposited dust as in the inhalable fraction.

Physicochemical characterization and size-resolved source apportionment of airborne particles in Himeji City, Japan

As a part of epidemiological study on the effects of the chemical composition of airborne particulate matter (PM) and ozone on asthma attacks, we carried out size-resolved sampling of PM in Himeji City, Japan and elemental and ionic composition analyses of the PM samples. Size-resolved PM was collected using a 3-stage NLAS impactor (Tokyo Dylec Co., Ltd.; particle cut size at sampling stages was 10, 2.5 and 1.0 [Formula: see text]m for a flow rate of 3 L/min) with a 1-week sampling interval from November 2009 to May 2012. Concentrations of several elemental and ionic species in the PM samples were determined by PIXE and ion chromatography analysis, respectively. In addition, source apportionment analysis of the PM was performed by positive matrix factorization (PMF) model using the analytical data of size-resolved particles. The research results are important for the physicochemical characterization of PM in the atmosphere, enabling evaluation of various PM emission sources and atmospheric processes. Of particular note is that the PM10 consisted mainly of [Formula: see text] and [Formula: see text], and PM2.5 consisted only of [Formula: see text]. This is believed to suggest the different formation processes of [Formula: see text] and [Formula: see text]. Based on the results from the PMF model analysis, the particles larger then PM2.5 were estimated to have been from soil and sea salt particles. On the other hand, the particles smaller than PM2.5 were estimated to have been from soot, smoke and secondary particles. In particular, the majority of particle smaller than PM1.0 were estimated to be secondary sulfate particles.

Determining the influence of different atmospheric circulation patterns on PM10 chemical composition in a source apportionment study

This study combines a set of chemometric analyses with a source apportionment model for discriminating the weather conditions, local processes and remote contributions having an impact on particulate matter levels and chemical composition. The proposed approach was tested on PM10 data collected in a semi-rural coastal site near Venice (Italy). The PM10 mass, elemental composition and the water soluble inorganic ions were quantified and seven sources were identified and apportioned using the positive matrix factorization: sea spray, aged sea salt, mineral dust, mixed combustions, road traffic, secondary sulfate and secondary nitrate. The influence of weather conditions on PM10 composition and its sources was investigated and the importance of air temperature and relative humidity on secondary components was evaluated. Samples collected in days with similar atmospheric circulation patterns were clustered on the basis of wind speed and direction. Significant differences in PM10 levels and chemical composition pointed out that the production of sea salt is strongly depending on the intensity of local winds. Differently, typical primary pollutants (i.e. from combustion and road traffic) increased during slow wind regimes. External contributions were also investigated by clustering the backward trajectories of air masses. The increase of combustion and traffic-related pollutants was observed when air masses originated from Central and Northwestern Europe and secondary sulfate was observed to rise when air masses had passed over the Po Valley. Conversely, anthropogenic contributions dropped when the origin was in the Mediterranean area and Northern Europe. The chemometric approach adopted can discriminate the role local and external sources play in determining the level and composition of airborne particulate matter and points out the weather circumstances favoring the worst pollution conditions. It may be of significant help in designing local and national air pollution control strategies.

Trace metal composition of airborne particulate matter in the coal mining and non–mining areas of Dhanbad Region, Jharkhand, India

This study reports the ambient concentrations of trace metals (in PM10) measured in the coal mining and non-mining areas of Dhanbad region, Jharkhand, India. Trace metal analysis was carried out using EPM 2000 filter paper followed by acid digestion, extraction and analysis through Atomic Absorption Spectrophotometer (AAS). The mean concentrations of trace metals were found in the order of Fe>Cu>Zn>Mn>Cr>Cd>Pb>Ni. Mean Pb concentrations were found to be ranging from 0.024μg/m3 to 0.32μg/m3, Ni 0.002μg/m3 to 0.02μg/m3, Cu 0.06μg/m3 to 6.32μg/m3 while Mn varied from 0.14μg/m3 to 1.9μg/m3. Fe, Zn, Cd and Cr varied from 1.43μg/m3 to 28.48μg/m3, 0.16μg/m3 to 2.55μg/m3, 0.03μg/m3 to 0.07μg/m3 and 0.11μg/m3 to 0.42μg/m3 respectively. Univariate (correlation study) and Multivariate statistical analysis were adopted including; factor analysis and enrichment factor analysis to identify the sources and their contributions to particulate matter. The major sources of airborne trace metals identified were mainly coal mining and associated activities, emissions from automobile exhaust and industries, resuspended soil dust and earth crust, biomass burning, oil combustion, and fugitive emissions.

Cytotoxic and proinflammatory effects of ambient and source-related particulate matter (PM) in relation to the production of reactive oxygen species (ROS) and cytokine adsorption by particles

The composition of airborne particulate matter (PM) varies widely depending on its source, and recent studies have suggested that particle-associated adverse health effects are related to particle composition. The objective of this study was to compare the biological/toxicological effects of different source-related PM. Specifically, we investigated the biological/toxicological effects of standard reference materials (SRMs): non-ferrous dust (PD-1, industrial), urban PM (UPM, SRM1648a), and diesel PM (DPM, SRM2975), and ambient PM2.5 (PM with an aerodynamic diameter <2.5 µm) collected at an urban site (Toronto, Canada). The dithiothreitol assay was used to measure the redox activity of the particles. Human alveolar epithelial cells (A549) were exposed to a range of concentrations (10–1000 µg/ml) of total PM, and the respective water-soluble and insoluble fractions, for 24 h. Biological responses were then evaluated in terms of cytotoxicity and interleukin (IL)-8 release, and compared with the PM composition and redox activity. We demonstrated that transition metal-enriched PD-1 exhibited the greatest cytotoxic effect (LD50 values of 100–400 µg/ml vs. >1000 µg/ml for the SRM1648a, SRM2975, and ambient PM2.5). Similarly, the PM-induced release of IL-8 was greatest for PD-1 (~6–9 ng/ml vs. ~1.5–3 ng/ml for others). These endpoints were more responsive to metals as compared with compared with secondary inorganic ions and organic compounds. Interestingly, we demonstrated a high degree of adsorption of IL-8 to the various SRMs and ambient PM2.5, and subsequently derived a new correction method to aid in interpretation of these data. These characteristics likely impart differential effects toward the toxic and immune effects of PM.

Major ionic species in size-segregated aerosols and associated gaseous pollutants at a coastal site on the Belgian North Sea

The chemical composition of airborne particulate matter (PM) was studied at a coastal region near De Haan, Belgium, during a winter-spring and a summer campaign in 2006. The major ionic components of size-segregated PM, i.e. NH(4)(+), Na(+), K(+), Mg(2+), Ca(2+), Cl(-), NO(3)(-), and SO(4)(2-), and related gaseous pollutants (SO(2), NO(2), NH(3), HNO(2), and HNO(3)) were monitored on a daily basis. Air mass backward-trajectories aided in evaluating the origin of the diurnal pollution load. This was characterised with high levels of fine secondary inorganic aerosols (NH(4)(+), NO(3)(-), and non-sea-salt SO(4)(2-)) for continental air masses, and sea-salts as the dominant species in coarse maritime aerosols. Seasonal variations in the level of major ionic species were explained by weather conditions and the release of dimethyl sulfide from marine regions. This species was responsible for an increased sea-salt Cl(-) depletion during summer (56%), causing elevated levels of HCl. Neutralisation ratios for the coarse fraction (0.6-0.8) suggested a depleted NH(4)(+) level, while that for the fine fraction (1.1-1.3) had definitely an excess of NH(4)(+), formed by the neutralisation of HCl. The results of factor analysis and the extent of SO(2) oxidation indicated that the major ionic species originated from both local and remote sources, classifying the Belgian coastal region as a combined source-receptor area of air pollution.

Application of EPMA and XRF for the investigation of particulate pollutants in the field of cultural heritage

For an integrated assessment of airborne pollutants, their concentrations and their sources have to be investigated along with possible ways of deterioration of the objects of art. The chemical composition and size characterization of atmospheric particulate pollutants is possible by computer-controlled electron probe microanalysis (CC-EPMA) at the single particle level, and energy-dispersive X-ray fluorescence (EDXRF) for bulk analysis. We report on the chemical composition of airborne particulate matter sampled at various European churches and museums.