Composition Of PM2 Research Articles

Evolution of Particulate Matter in a Municipal Solid Waste Incinerator: Probing into the Effects of a Rotary Spray Semi-dry Scrubber and a Baghouse

Systemic field measurements of PM10 were carried out on a grate-type municipal solid waste (MSW) incinerator to investigate the formation characteristics of PM10 and the effects of a semi-dry flue gas deacidification scrubber (lime slurry spraying and activated carbon powder injection) and a baghouse on its emission. The particle size distribution (PSD), mass concentration, chemical composition, and micromorphology of PM10 in the flue gas at the scrubber inlet, the scrubber outlet, and the baghouse outlet were comprehensively determined. The results showed that the PSD of PM10 formed from MSW incineration was tri-modal. The peak of PM in the central mode (0.3–3 μm) was dramatically higher than that of either the ultrafine mode or the coarse mode, most possibly due to the high contents of volatile mineral matter (e.g., Na and Cl) and nanomaterial-/micro-material-containing wastes in the MSW fuels. The mass yields of PM1, PM2.5, and PM10 decreased by 28.24, 59.26, and 53.91%, respectively, after passing through the semi-dry scrubber; however, some new particles formed from the slurry droplet. The baghouse could effectively remove the PM with the removal efficiencies for PM1, PM2.5, and PM10 being over 99.95%. Comparatively speaking, more PM2.5 was generated in the combustion of MSWs than agroforestry or coal in the furnace.

First evidence of glyphosate and aminomethylphosphonic acid (AMPA) in the respirable dust (PM10) emitted from unpaved rural roads of Argentina

The aim of this work was to compare the concentration of glyphosate and AMPA in the PM10 and the actual PM10 emission from agricultural soils and unpaved roads, located inside and outside farm fields. To determine the actual PM10 emission by wind erosion, the actual wind erosion was estimated using the Wind Erosion Equation, and the PM10 emission efficiency was measured with the Easy Dust Generator. PM10 was collected in an electrostatic precipitator coupled to the Easy Dust Generator. Actual PM10 emission was 11.5 g ha−1 year−1 in agricultural soils and 4711.4 g ha−1 year−1 in unpaved roads. The high value of actual PM10 emission in unpaved roads was due to their high actual wind erosion and the high PM10 emission efficiency, while the low value in agricultural soils was due to their low actual wind erosion. Content of glyphosate in the PM10 ranged from 59 to 359 μg kg−1 in agricultural soils, from 382 to 454 μg kg−1 in unpaved roads inside farm fields, and from 39 to 639 μg kg−1 in unpaved roads outside farm fields. Content of AMPA in the PM10 ranged from 387 to 7228 μg kg−1 in agricultural soils, from 900 to 4138 μg kg−1 in unpaved roads inside farm fields, and 98 to 500 μg kg−1 in unpaved roads outside farm fields. AMPA concentration in PM10 was higher than that of glyphosate due to the longer persistence of AMPA than glyphosate. Glyphosate and AMPA concentrations in PM10 were higher than in soil, which is an additional risk that should be considered when the effect of PM10 emitted by agricultural soils and unpaved roads on human health are evaluated. Our results show that the amount and chemical composition of PM10 emitted by wind erosion from unpaved roads should be studied in other regions.

Influence of mineral dust on the concentration and composition of PM10 in the city of Constantine

Abstract Measurements of Saharan dust (SD) inputs are very scarce in the vicinity of the Saharan desert. This work aims to identify Saharan dust intrusions and evaluate their contribution to annual and daily PM10 at an urban background site located in the city of Constantine in Algeria. A reliable identification of SD days was carried out using aerosol maps provided by BSC-DREAM model and the information provided by HYSPLIT air mass back trajectories. SD is mainly composed of mineral dust (MD) due to the proximity of the Sahara to the study site. MD was determined by chemical speciation analysis and was estimated on SD days and non SD days. The contribution of MD on SD days was about 50% higher than that observed on non SD days. The observed average PM10 concentration during the study period was 56 ± 32.0 μg/m3. During SD days, the average PM10 concentration was 70 ± 36.1 µg/m3. On average, the PM10 concentration increased by 17.05 ± 12.7 μg/m3 on SD days. SD events contributed between 0.6 and 41.5 µg/m3 to the daily PM10 concentrations, whereas the average contribution to the annual PM10 concentration was 7.2 ± 11.8 μg/m3 i.e., 12.8 ± 15.5%. After the extraction of the SD load, the annual WHO air quality guideline (AQG) was still exceeded. SD incursions led to an increase of most metal elements concentrations by a factor ranging from 1.05 to 3.33. Our results point out that SD outbreaks are quite frequent as they occurred 42.2% of the annual days.

Long-term trends in local and transported PM2.5 pollution in New York City

Previous source apportionment analyses of New York City (NYC) PM2.5 have found that transported pollution can account for up to half of total fine particulate matter (PM2.5) mass. In recent years, several local and federal emissions regulations on both the transportation and energy sector have been introduced, such as the Clean Heavy-Duty Bus and Truck Rule, and policies related to the NYC Clean Heat Program. Since the implementation of these regulations, there have been limited studies on regional transport of particulate air pollution into NYC. This paper aims to quantify long-term changes in local and regional contributions to PM2.5 in NYC. The composition of PM2.5 in NYC over the period 2002–2018 was evaluated using data from the US Environmental Protection Agency (EPA) Chemical Speciation Network (CSN) and the New York City Community Air Survey (NYCCAS). Background site data obtained from EPA CSN was used to assess regional transport. Two estimates of transported PM2.5 were calculated, one assuming that transported PM2.5 consists solely of ammonium sulfate and ammonium nitrate as a lower bound and the other taking into account organic matter (OM) as an upper bound. Using this method, regional transport was estimated to account for 25–46% of total PM2.5 measured in NYC in 2018, down from 46 to 57% in 2002. Secondary PM2.5 output from the Community MultiScale Air Quality (CMAQ) model for the years 2008, 2011, and 2017 was used as an additional upper-bound estimate of regional transport (56%, 35%, and 30%, respectively). In addition to CMAQ model estimates of sulfate, nitrate, and primary emitted PM2.5, land-use regression (LUR) models for sulfur, vanadium, copper, nickel, and PM2.5 measurements at 60 locations across NYC during the winter and summer seasons of 2008–2015 were assessed for changes in local emissions. The results indicate decreased emissions from residual oil burning, traffic, and ships. As a consequence of regional and local changes, PM2.5 in NYC had fallen to approximately 55% of its 2002 levels by 2018. The observed temporal and spatial trends of PM2.5 and its components point to the effect of regulations as well as economic influences on fuel usage, such as the decline of coal in favor of natural gas, in reducing air pollution over the last two decades. While other major PM2.5 constituents have declined, OM is becoming an increasingly dominant component with potential implications for PM2.5 toxicity. Further improvements in NYC air quality could be achieved by targeting sources of ambient OM, such as commercial cooking, traffic, and biomass burning for residential heating.

Development and evaluation of a mobile laboratory for collecting short-duration near-road fine and coarse ambient particle and road dust samples

ABSTRACT This study used fine and coarse PM concentrator technology in a Mobile Particle Concentrator Platform (MPCP) designed and built to allow the collection of large amounts of ambient PM, enabling time-resolved speciation analysis, which would not be feasible using conventional methods. One hour of sampling yielded sufficient sample loading for trace elemental analysis using X-Ray Fluorescence (XRF). In addition, we developed a novel Road Dust Aerosolizer (RDA) sampler in order to collect PM2.5 and PM10 surface road dust in situ. This sampler aerosolizes dust from the road surface, simulating ambient road dust resuspension, resulting in measured PM composition and size more appropriately (and less labor-intensive) than those obtained from studies using bulk road dust sieved and re-suspended in the laboratory. Overall, our modified fine and coarse particle concentrators yielded good reproducibility between co-located samples and sufficient loading for trace elemental analysis. For particle mass concentration, we observed a relative error of 3% and 4% among pairs of filters for fine and coarse concentrators, respectively; confirming that the mass collected on an unweighted quartz filter in parallel with a Teflon filter will have the same PM mass as the weighed Teflon filter. For samples with elements that are well above the LOD, relative uncertainty values were between 5% and 10% for the fine and 3% and 10% for the coarse. Our results show that the RDA system has an excellent precision for mass and elements as well. The relative error for mass is 7% for PM10 and 3% for PM2.5 within pairs and ranged from 2 to10% for elements. In conclusion, we developed a method for collecting PM10 and PM2.5 near-road air and surface road dust for short durations, which allows investigation of the composition of direct (airborne) and indirect (re-suspended road dust) non-tailpipe vehicular emissions. Implications: The methods we developed in this study allow the collection of one-hour PM10-2.5 and PM2.5–0.2 samples from near-road ambient air at several distances from the same roadway in 1 day, and collection of road dust directly from the road surface, with sufficient loading for trace elemental analysis. This will allow investigation of the composition of direct (airborne) and indirect (re-suspended road dust) vehicular emissions.

Disentangling multiple PM emission sources in the Po Valley (Italy) using honey bees

Particulate matter (PM) is a complex mixture of airborne chemical compounds commonly classified by their aerodynamic diameter. Although PM toxicity strongly depends on the morphology, chemical composition, and dimensions of particles, exposure limits set by environmental organisations only refer to the mean mass concentration of PM sampled daily or annually by monitoring stations.In this study, we used honey bees as sensors of airborne PM10 and PM2.5 in a highly polluted area of the Po Valley, northern Italy. Honey bees are an efficient sampler of airborne PM because, during flight and foraging activities, their pubescence promotes the accumulation of electrical charge on the body surface owing to air resistance, thus enhancing airborne PM attraction. Particles attached to the body of bees are readily accessible for physico-chemical characterisation using a scanning electron microscope coupled with X-ray spectroscopy (SEM/EDX). Our results demonstrate that residents in the study area are intermittently but chronically exposed to a well-defined spectrum of metal-bearing particles and mineral phases known to induce specific health outcomes.The morphology, size, and chemical composition of PM10 and PM2.5 detected on bees in the monitoring area were indicative of traffic, agricultural operations, and high-temperature combustion processes. The contribution of the A1 Milano-Bologna highway, local wheat and alfalfa cultivation, and the Parma incineration plant were clearly distinguishable. Our data also demonstrated that PM exposure levels may vary sharply throughout the year based on recurrent local activities.

Koncentracije i hemijski sastav suspendovanih čestica PM10 i PM2.5 u biblioteci u Boru, Srbija

This paper presents the PM10 and PM2.5 concentrations and results of chemical analyses of PM samples collected at the public library in Bor town, Serbia. Two sampling campaigns were carried out during six consecutive working days in June 2015 and in March 2016. The results show that PM10 and PM2.5 concentrations in the library were strongly connected with the respective PM concentrations in ambient air. So, most PM particles in the library originate from the outdoor air. High PM2.5/PM10 ratios in both indoor and outdoor environments indicate the considerable influence of anthropogenic air pollution sources, in this case, metallurgical processes in copper smelting plants. Because the new copper smelting plant started operating in 2016, it is necessary to conduct a new measurement campaign to determine whether there are changes in the concentration levels and chemical composition of PM in the indoor air of public and residential buildings in Bor

Toxicological Effects of Artificial Fine Particulate Matter in Rats through Induction of Oxidative Stress and Inflammation.

Airborne fine particulate matter with an aerodynamic diameter equal to or smaller than 2.5 μm (abbreviated as PM2.5) increases the risk of nasal lesions, but the underlying molecular mechanism has not been fully elucidated. In the atmosphere, the composition of PM2.5 collected varies in physical and chemical properties, which affects its damage to human health. Thus, we constructed artificial PM2.5 particles based on actual PM2.5 and investigated the in vivo effects of artificial PM2.5 exposure on the oxidative stress, inflammatory response, and nasal mucosa morphology of rats. The results showed that artificial PM2.5 is comparable in composition ratio, size, and morphology to actual PM2.5. This in vivo study indicated that artificial PM2.5 exposure reduces total superoxide dismutase and glutathione peroxidase activities, elevates malondialdehyde content in the nasal mucosa, and induces increased levels of pro-inflammatory mediators, including interleukin-1, interleukin-6 and tumor necrosis factor-α. Our data shows that artificial PM2.5 particles could be used for experimental study of PM2.5 toxicology, ensuring that the physical and chemical properties of experimental PM2.5 are relatively constant and allowing for repeatability of this research. Oxidative damage and inflammatory response may be the toxic mechanisms that cause nasal lesions after exposure to artificial PM2.5.

Risk assessment of mortality from acute exposure to ambient fine particles based on the different toxicities of chemical compositions in China

ABSTRACT Health risks, including mortalities and morbidities, attributed to chronic or acute exposure to ambient fine particulate matter (PM2.5), have been assessed based on the increments in ambient concentrations. Different toxicities of the various chemical compositions in PM2.5 mixtures have been confirmed by epidemiological evidence but have rarely been considered. We proposed an approach to calculate the disease burden of both the chemical components and concentrations of PM2.5 by combining their pre-established dose–response relationships with a multivariate Gaussian model. We estimated that PM2.5 mixtures account for 0.43 (95% CI: 0.29 ~ 0.56) million premature deaths in China in 2013, consistent with estimates based on single-pollutant models in quantifying the total risk but with differing risk distributions. The residential, an elemental carbon-rich emission sector, accounted for approximately a quarter of PM2.5 emissions, but for half of the premature deaths attributable to air pollution, due to the stronger toxicity of carbonaceous particles than other PM2.5 compositions. Conventional risk assessments based on PM2.5 mass assume equality in the toxicity of PM2.5 compositions and may therefore fundamentally underestimate the skewness of the risk distribution and the adverse health effects of particles from the residential emissions. The different toxicities of the of PM2.5 compositions modify the risk estimates and thus should be included in emission reduction plans.

Experimental investigation of a one-level eight-channel cyclone-separator incorporating quarter-rings

The main aim of this investigation was an experimental analysis of the air cleaning efficiency in a mock-up next-generation air cleaning device - one-level 8-channel industrial cyclone-separator with quarter-rings - while changing parameters of the inner structure and the assessment of the effects of dispersion of particulate matter. Therefore, the research was carried out in two stages: the first stage covered the analysis of the efficiency of the multi-channel cyclone with particulate matter of <20 and <50 ?m. During the second stage, a cascade impactor was used to measure the particle collection efficiency in the multi-channel cyclone by fractions: PM1, PM2.5 and PM10. Results of the tests with using the cascade impactor were compared to show changes in the PM composition before and after the multi-channel cyclone-separator. According to the obtained experimental data, the one-level 8-channel cyclone-separator collects 70 to 80 % of PM up to 10 ?m in size, 45 to 60 % of PM up to 2.5 ?m in size and 21 to 25 % of PM up to 1 ?m in size.

Simultaneous Measurements of PM2.5- and PM10-bound Benzo(a)pyrene in a Coastal Urban Atmosphere in Poland: Seasonality of Dry Deposition Fluxes and Influence of Atmospheric Transport

Parallel 24-h measurements of PM2.5- and PM10-bound benzo(a)pyrene (BaP) were conducted in a coastal urban region in northern Poland in 2019. The aim was to examine distribution profiles, dry deposition fluxes and perform a trajectory analysis to investigate potential source regions of pollutants. The mean ratio of PM2.5/PM10 was 0.70 ± 0.23, suggesting significant heterogeneity in PM composition during the study period, both in fine and coarse fraction. The measurements revealed a strong seasonal variation in the concentration and dry deposition fluxes of BaP. The peak BaP concentrations of 6.14 ng m–3 and 6.65 ng m–3, respectively in fine and coarse PM fractions were observed in December. They were directly attributed to local emission from major industrial (i.e., coal-fired power plants, refinery, solid waste burning, metal recycling plants) and residential sources (domestic heating units), and to the meteorological situation that led to the reduced dissipation of air pollutants and their transport outside the study domain. During the period from October to November, high Pb/Zn ratios in PM2.5 and PM10 were also observed, suggesting significant contribution of industrial emission (coal combustion) and local non-exhaust traffic emissions, including tyre abrasion in the case of Zn and the resuspension of road dust rich in Pb. The highest daily BaP deposition fluxes of 2652 ng m–2 (PM2.5) and 5561 ng m–2 (PM10) were reported in winter, while the lowest values of daily BaP deposition (2 ng m–2) were found during spring and summer measurements. Additionally, the three-dimensional FLEXTRA transport model was used to identify the impact of different sources on air masses over the study domain. FLEXTRA results showed that the air masses transported from distant S to W regions greatly affected the chemical composition of PM2.5 and PM10 during autumn and winter.

Impact of Biomass Burning on Air Quality in Temuco City, Chile

ABSTRACT Residential wood burning emits a complex mixture of particulate and gaseous compounds. In this article we show an in-depth chemical characterization of particulate matter evidencing the impact of biomass burning on the urban air quality in Greater Temuco, the capital city of the Araucania Region, Chile. The measurements were carried out at two sites, Las Encinas and Padre Las Casas, in spring and winter. Extremely high fine particulate matter (PM2.5) concentrations (up to 700 µg m–3) were frequently observed at both stations in the wintertime, while in spring, PM2.5 concentrations were significantly lower (campaign-average 6.4 and 8.6 µg m–3 in Las Encinas and Padre Las Casas, respectively). Chemical composition of submicron PM was dominated by organics (average 87%) followed by inorganic ions (10–30%) and a minor contribution of black carbon (< 5%). In the wintertime, atmospheric levels of biomass burning tracers, such as levoglucosan, potassium and chloride, were elevated and their diurnal profiles showed a significant concentration increase in the evening. Diurnal profiles combined with the in-depth chemical analysis clearly indicated that in the wintertime local biomass burning was the main source of air pollutants in the region. Furthermore, in winter, most of the high concentration events correlated with the periods with high surface pressure, low temperature and low wind speed. These events matched with higher temperatures at high altitude than at the surface characterizing the typical profile of a vertical inversion that prevents the dilution of air pollutants.

Cytotoxicity and chemical composition of women's personal PM2.5 exposures from rural China.

Personal exposure PM samples aid in determining the sources and chemical composition of real-world exposures, particularly in settings with household air pollution. However, their use in toxicological research is limited, despite uncertainty regarding health effects in these settings and evidence of differential toxicity among PM2.5 sources and components. This study used women's PM2.5 exposure samples collected using personal exposure monitoring in rural villages in three Chinese provinces (Beijing, Shanxi, and Sichuan) during summer and winter. Water-soluble organic carbon, ions, elements, and organic tracers (e.g. levoglucosan and polycyclic aromatic hydrocarbons [PAHs]) were quantified in water and organic PM2.5 extracts. Human lung epithelial cells (A549) were exposed to the extracts. Cell death, reactive oxygen species (ROS), and gene expression were measured. Biomass burning contributions were higher in Sichuan samples than in Beijing or Shanxi. Some PM characteristics (total PAHs and coal combustion source contributions) and biological effects of organic extract exposures (cell death, ROS, and cytokine gene expression) shared a common trend of higher levels and effects in winter than in summer for Shanxi and Beijing but no seasonal differences in Sichuan. Modulation of phase I/AhR-related genes (cyp1a1 and cyp1b1) and phase II/oxidative stress-related genes (HO-1, SOD1/2, NQO-1, and catalase) was either low or insignificant, without clear trends between samples. No significant cell death or ROS production was observed for water extract treatments among all sites and seasons, even at possible higher concentrations tested. These results support organic components, particularly PAHs, as essential drivers of biological effects, which is consistent with some other evidence from ambient PM2.5.

Seasonal Variability of PM10 Chemical Composition Including 1,3,5-triphenylbenzene, Marker of Plastic Combustion and Toxicity in Wadowice, South Poland

ABSTRACT The objective of this research was to evaluate the seasonal variation of the chemical composition of PM10 including polycyclic aromatic hydrocarbons (PAHs) and 1,3,5-triphenylbenzene (135TPB), which is a well known marker of plastic combustion. The presented work is a part of the project concerning assessment of air quality of small cities around Krakow agglomeration. Monitoring campaign was conducted between February and October 2017 in Wadowice, a small city in Krakow agglomeration, South Poland. To widen the knowledge of Krakow's agglomeration air quality, other aerosol chemical components were analyzed. Ion chromatography (IC) was used for analysis of cations and anions, while gas chromatography-mass spectrometry (GC-MS) was used for PAHs. Samples were also analyzed for OC/EC (organic/elemental carbon) by thermal-optical analysis with a Sunset Laboratory carbon analyzer, Sunset Inc. The co-combustion of plastic in addition to conventional fuels and the respective impact on air quality is evaluated via the concentration of the marker compound 135TPB. Co-combustion of plastics with fuels resulted in a higher abundance of fluorene and most of 4–6 ring PAHs, in agreement with recent literature. Authors proved that other sources besides plastic burning, including road transport, residential heating, residential combustion, industrial emissions, affect the air quality in South Poland. The modeling tool Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT), developed by NOAA’s Air Resources Laboratory, was used to define the possible areas outside Wadowice contributing to urban air pollution.

Source contribution and origin of PM10 and arsenic in a complex industrial region (Huelva, SW Spain)

Air pollution coming from industrial activities is a matter of interest since their emissions can seriously affect to the human health of nearby populations. A more detailed study about industrial emissions is required in order to discriminate different activities contributing to pollutant sources. In this sense, gaseous pollutants (NO2, SO2 and O3) and PM10 levels has been studied in a complex industrial area in the southwest of Spain (La Rabida and the nearby city of Huelva) during the period 1996–2017. Hourly, daily, monthly and annual variations of PM10 and gaseous pollutants concentrations point to the industrial activity as the main SO2 source. Furthermore, traffic and resuspension emissions contribute to the NO2 and PM10 levels, respectively. Results from chemical composition of PM10 at both sites during the period 2015–2017 are characterized by high concentrations of the crustal components derived from natural and local resuspension. Arsenic is found to be the main geochemical anomaly at La Rabida (annual mean of 7 ng m−3), exceeding the European annual target of 6 ng m−3, which supposes a risk for the nearby population. An emission source from Cu-smelter has been identified in La Rabida and Huelva. A second source corresponding to emissions from polymetallic sulfides handling in a port area has been described for the first time in La Rabida. In addition, arsenic speciation results have identified three different As impacts scenarios as a function of the dominant wind direction, the SO2 episodes and the As extraction efficiency: impact of the Cu-smelter, impact of the bulk polymetallic sulfides and a mixed impact of both sources.

The morphology and chemical composition of the urban PM10 near a steel plant in Apulia determined by scanning electron microscopy. Source Apportionment

PM10 samples were collected in a site of Apulia region (South-East Italy) near a steel plant when the winds were blowing from the NW and the SE to exclude and include, respectively, the contribution of the industrial source in order to study the aerosol particles in detail and attribute them to the most appropriate emission sources. Size, morphology and chemical composition of 6500 individual particles, with an equivalent spherical diameter (ESD) between 0.4 ˗ 1 μm, 1 ˗ 2.5 μm and 2.5 ˗ 10 μm, were analysed by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM - EDX). These particles were classified in the thirteen groups: aluminosilicates, silicates, iron oxides, metal oxides, iron mixtures, aluminosilicates with sulphur, calcium sulphates, silicate-sulphate mixed particles, carbonates, carbonates-silicates, soot, biological particles and carbon rich particles. Source apportionment analyses were carried out separately for the three dimensional ranges considered and for the two wind directions from North-West and South-East and nine main sources were distinguished. The soil and the soot components are higher when the wind blow from the NW than the SE, while the anthropogenic sources are evident with the wind from the SE due to the presence of iron and carbonaceous particles characterized by typical spherical shapes and chemical elements as Ca, Na and K which could to be indicative of industrial activity. The single particle analysis let better identify the emission sources that persist on the territory, attributing to them the particles characterized by peculiar morphology and chemical composition.

Trace metal composition of rainwater and aerosol from Kolkata, a megacity in eastern India

India is one of the world's wettest countries receiving over 1000 mm of rainfall annually and also one of the countries experiencing regular floods and droughts. This study quantifies elemental composition of rainwater and aerosol collected simultaneously during 2019 monsoon season from Kolkata, a megacity in Eastern India marred by air pollution to understand sources and estimate wet deposition flux. Elemental composition (Na, Ca, Mg, Al, Fe, Mn, V, Cr, Ni, Cu, Zn, Cd, Pb) of rainwater was measured in ICP MS along with pH, conductivity, chloride (Cl−), nitrate (NO3−) and sulphate (SO42−) ions. Trace metal composition of PM10 collected in between rain events were also analysed to understand anthropogenic sources and atmospheric leaching of metals. Crustal enrichment factors (EFs) identified anthropogenic sources for Ni, Cu, Zn, Pb and Cd in PM10. Principal component analysis (PCA) identified three anthropogenic sources, industrial emission, traffic emission and waste incineration in addition to the natural background from the crustal dust for the aerosol metals. Majority of rainwater samples had almost neutral pH (average 6.81 ± 0.74, 1SD), with a range of 5.4 to 8.0. In rainwater, Na and Cl− had marine origin and majority of SO42− had non-marine sources. Cu, Zn, Cd, V, Cr and Pb concentrations of rainwater follow the trend in PM10 most likely because part of the metals are derived from aerosol leaching. The EFs indicated that all the metals except Fe had anthropogenic origin in rainwater. The wet deposition fluxes were in the order of Ca > Na > Mg > Al > Zn > Fe > Mn > Cu > Ni > Pb > Cr > V > Cd. Overall, the results show significant influence of anthropogenic sources on rainwater chemistry in addition to natural soil dust and marine aerosols. In spite of anthropogenic influence, the trace metal and anion concentrations in rainwater are well within the limits prescribed by World Health Organization (WHO), European Union (EU), USA and Indian Drinking Water Standards.

Chemical Composition and Source Apportionment of PM10 in a Green-Roof Primary School Building

Research on air quality issues in recently refurbished educational buildings is relatively limited. However, it is an important topic as students are often exposed to high concentrations of air pollutants, especially in urban environments. This study presents the results of a 25-day experimental campaign that took place in a primary school located in a densely built-up area, which retains a green roof system (GRS). All measurements refer to mass concentrations and chemical analysis of PM10 (particulate matter less than 10 micrometers), and they were implemented simultaneously on the GRS and within the classroom (C3) below during different periods of the year. The results demonstrated relatively low levels of PM10 in both experimental points, with the highest mean value of 72.02 μg m−3 observed outdoors during the cold period. Elemental carbon (EC) was also found be higher in the ambient environment (with a mean value of 2.78 μg m−3), while organic carbon (OC) was relatively balanced between the two monitoring sites. Moreover, sulfate was found to be the most abundant water soluble anion (2.57 μg m−3), mainly originating from ambient primary SO2 and penetrating into the classroom from windows. Additionally, the crustal origin of particles was shown in trace metals, where Al and Fe prevailed (9.55% and 8.68%, respectively, of the total PM10). Nevertheless, infiltration of outdoor particles within the classroom was found to affect indoor sources of metals. Finally, source apportionment using a positive matrix factorization (PMF) receptor model demonstrated six main factors of emissions, the most important of which were vehicles and biomass burning (30.30% contribution), along with resuspension of PM10 within the classroom from human activities (29.89% contribution). Seasonal variations seem to play a key role in the results.

Influence of start-up phase of an incinerator on inorganic composition and lead isotope ratios of the atmospheric PM10

A municipal solid waste incinerator (MSWI) was installed in a peripheral area of the city of Turin. In this study, we evaluated the contribution of this plant to the massive concentration of PM10, to its chemical composition and to the distribution of the lead isotopes during the start-up phase.We assessed the inorganic composition of PM10 collected in the vicinity of the Turin incinerator by inductively coupled plasma atomic emission spectroscopy (ICP-AES), magnetic sector inductively coupled plasma mass spectrometer (SF-ICP-MS) and ion chromatography (IC). The lead isotope ratios in PM10 samples were determined by SF-ICP-MS by a method developed and optimized using experimental design approach. Element trends and data chemometric treatment evidence that the vehicular traffic, increased in this area due to the opening of the MSWI plant, and, to a lesser degree, the direct incinerator emissions influence As, Cd, Cr, Cu, Ba, Mo, Pb, Sn and Zn concentrations. As a whole, however, the element concentrations in PM10 and the Enrichment Factors (EFs) were comparable with the values reported for other urban sites and target pollutant concentrations of MSWI emissions, namely Cd, Cr, Cu and Pb, were lower than in PM10 emitted from older MSWIs. This confirms that incinerators of new installation have a lower impact on atmospheric PM10 composition thanks to stricter current legislation and up-to-date technologies. The lead isotope ratios investigation allowed to distinguish the diverse sources (crustal, vehicular traffic and MSWI) that influence lead concentration in PM10 collected near incinerator during start-up phase.

Integrated Evaluation of Indoor Particulate Exposure: The VIEPI Project

Despite the progress made in recent years, reliable modeling of indoor air quality is still far from being obtained. This requires better chemical characterization of the pollutants and airflow physics included in forecasting tools, for which field observations conducted simultaneously indoors and outdoors are essential. The project “Integrated Evaluation of Indoor Particulate Exposure” (VIEPI) aimed at evaluating indoor air quality and exposure to particulate matter (PM) of humans in workplaces. VIEPI ran from February 2016 to December 2019 and included both numerical simulations and field campaigns carried out in universities and research environments located in urban and non-urban sites in the metropolitan area of Rome (Italy). VIEPI focused on the role played by micrometeorology and indoor airflow characteristics in determining indoor PM concentration. Short- and long-term study periods captured diurnal, weekly, and seasonal variability of airflow and PM concentration. Chemical characterization of PM10, including the determination of elements, ions, elemental carbon, organic carbon, and bioaerosol, was also carried out. Large differences in the composition of PM10 were detected between inside and outside as well as between different periods of the day and year. Indoor PM composition was related to the presence of people, to the season, and to the ventilation regime.