Sources Of Airborne Particles Research Articles

Micro- and nanoplastics transfer from seawater to the atmosphere through aerosolization under controlled laboratory conditions

Sea spray has been suggested to enable the transfer of micro- and nanoplastics (MNPs) from the ocean to the atmosphere, but only a few studies support the role of sea spray aerosols (SSAs) as a source of airborne particles. We demonstrated that MNPs are aerosolized during wave action, via SSAs, under controlled laboratory conditions. We used a mini-Marine-Aerosol-Reference-Tank (miniMART), a device that mimics naturally occurring physical mechanisms producing SSAs, and assessed the aerosolization of fluorescent polystyrene beads (0.5-10 μm), in artificial seawater. The SSAs contained up to 18,809 particles/mL of aerosols for 0.5 μm beads, with an enrichment factor of 19-fold, and 1977 particles/mL of aerosols for 10 μm beads with a 2-fold enrichment factor. Our study demonstrates that the use of the miniMART is essential to assess MNPs aerosolization in a standardized way, supporting the hypothesis which states that MNPs in the surface of the ocean may be transferred to the atmosphere.

102 Application of Quantitative Mineralogy to Determine Sources of Airborne Particles at a European Copper Smelter

Abstract To ensure that regulatory compliance is maintained at mineral processing operations, worker exposure is regularly monitored. Determining the quantity and type of airborne particles permits the operation to identify the sources of dust, implement proper dust suppressant strategies, and ultimately, limit worker exposure. Conventional methods of analysis, such as chemical assay, are unable to rigorously differentiate between phases containing the same elements and may result in ambiguity related to identifying the source of airborne dust. A combination of Quantitative Evaluation of Materials by Scanning Electron Microscope (QEMSCAN) and chemical characterization has been used to evaluate personally taken size selective aerosol samples at key locations throughout a Cu smelter in Europe. Surface samples were also examined using higher resolution measurements. The Cu phases present in the workplace air samples are reflective of the activities performed at specific locations. Near the anode and electric furnace, the majority of Cu in the airborne dust is carried in metals and oxide phases (60-70%), and in the batch preparation area where Cu concentrate is received, significant amounts of Cu are carried in sulfide minerals (chalcocite, chalcopyrite/bornite, >40%). The results of the analysis will aid in the identification of the origin of emissions specific to location and activity, assist personnel in developing the appropriate mitigation strategies to limit workers exposure, and further understanding of the health risks associated with exposure. Additional metals of concern (e.g, Pb, As, and Cd) are also considered throughout this program. Speaker Biography Michelle Kelvin is a geoscientist and environmental mineralogist. She specializes in characterizing dust emissions that originate from industrial operations using modern geochemical methods and X-ray beam technologies.

Application of quantitative mineralogy to determine sources of airborne particles at a European copper smelter

Copper processing operations, such as smelters and refineries, can produce airborne particles that may impact the health of workers. At these operations, worker exposure to chemicals are regularly monitored to ensure that regulatory compliance with occupational exposure limit values (OELVs) are maintained. Determining the type of airborne particles present is important for characterizing the composition of dust exposures and better understanding the relationship between worker exposure and health. Routine methods of analysis (e.g., chemical assay) are unable to differentiate between phases containing the same elements and may result in ambiguity. A novel approach of a combination of Quantitative Evaluation of Materials by Scanning Electron Microscope (QEMSCAN) and chemical characterization was used here to evaluate airborne and settled dust collected at key locations throughout a copper smelter in Europe. The copper (Cu) phases present in the airborne dust are indicative of the activities performed at specific locations. In the batch preparation area where Cu concentrate is received, significant amounts of Cu were carried in sulfidic minerals (chalcocite, chalcopyrite/bornite, >40%), whereas near the anode and electric furnace, the majority of Cu in dust was carried in metallic and oxidic phases (60–70%). Particle size analysis of the settled dust indicates that the sulfidic and oxidic Cu minerals are more likely to become airborne over metallic Cu. Furthermore, overall Cu concentrations decreased with particle size where metallic and oxidic Cu dominate, which suggests that differences in the proportion of Cu forms present in the dust will impact how much Cu ends up in the respirable fraction. These results highlight the need to understand the characterization of Cu in dust in order to set better OELVs.

Identification of specific sources of airborne particles emitted from within a complex industrial (steelworks) site

A case study is provided of the development and application of methods to identify and quantify specific sources of emissions from within a large complex industrial site. Methods include directional analysis of concentrations, chemical source tracers and correlations with gaseous emissions. Extensive measurements of PM10, PM2.5, trace gases, particulate elements and single particle mass spectra were made at sites around the Port Talbot steelworks in 2012. By using wind direction data in conjunction with real-time or hourly-average pollutant concentration measurements, it has been possible to locate areas within the steelworks associated with enhanced pollutant emissions. Directional analysis highlights the Slag Handling area of the works as the most substantial source of elevated PM10 concentrations during the measurement period. Chemical analyses of air sampled from relevant wind directions is consistent with the anticipated composition of slags, as are single particle mass spectra. Elevated concentrations of PM10 are related to inverse distance from the Slag Handling area, and concentrations increase with increased wind speed, consistent with a wind-driven resuspension source. There also appears to be a lesser source associated with Sinter Plant emissions affecting PM10 concentrations at the Fire Station monitoring site. The results are compared with a ME2 study using some of the same data, and shown to give a clearer view of the location and characteristics of emission sources, including fugitive dusts.

Emission rates and the personal cloud effect associated with particle release from the perihuman environment.

Inhalation exposure to elevated particulate matter levels is correlated with deleterious health and well-being outcomes. Despite growing evidence that identifies humans as sources of coarse airborne particles, the extent to which personal exposures are influenced by particle releases near occupants is unknown. In a controlled chamber, we monitored airborne total particle levels with high temporal and particle-size resolution for a range of simulated occupant activities. We also sampled directly from the subject's breathing zone to characterize exposures. A material-balance model showed that a sitting occupant released 8 million particles/h in the diameter range 1-10μm. Elevated emissions were associated with increased intensity of upper body movements and with walking. Emissions were correlated with exposure, but not linearly. The personal PM10 exposure increment above the room-average levels was 1.6-13μg/m3 during sitting, owing to spatial heterogeneity of particulate matter concentrations, a feature that was absent during walking. The personal cloud was more discernible among larger particles, as would be expected for shedding from skin and clothing. Manipulating papers and clothing fabric was a strong source of airborne particles. An increase in personal exposure was observed owing to particle mass exchange associated with a second room occupant.

Indoor airborne particle sources and outdoor haze days effect in urban office areas in Guangzhou

To identify the sources of PM2.5 pollutants in work environments and determine whether the air quality inside an office was affected by a change in outdoor pollution status, concurrent indoor and outdoor measurements of PM2.5 were conducted at five different office spaces in the urban center of Guangzhou on low pollution days (non-episode days, NEDs), and high pollution days (haze episode days, EDs). Indoor-outdoor relationships between the PM2.5 mass and its chemical constituents, which included water-soluble ions, carbonaceous species, and metal elements, were investigated. A principle component analysis (PCA) was performed to further confirm the relationship between the indoor and outdoor PM2.5 pollution.The results reveal that (1) Printing and ETS (Environmental tobacco smoking) were found to be important office PM2.5 sources and associated with the enrichment of SO42-, OC, EC and some toxic metals indoors; (2) On EDs, serious outdoor pollution and higher air exchange rate greatly affected all studied office environments, masking the original differences of the indoor characteristics (3) Fresh air system could efficiently filter out most of the outside pollutants on both NEDs and EDs.Overall, the results of our study suggest that improper human behavior is associated with the day-to-day generation of indoor PM2.5 levels and sporadic outdoor pollution events can lead to poor indoor air quality in urban office environments. Moreover, fresh air system has been experimentally proved with data as an effective way to improve the air quality in office.

Source apportionment of fine and coarse particles at a roadside and urban background site in London during the 2012 summer ClearfLo campaign

London, like many major cities, has a noted air pollution problem, and a better understanding of the sources of airborne particles in the different size fractions will facilitate the implementation and effectiveness of control strategies to reduce air pollution. Thus, the trace elemental composition of the fine and coarse fraction were analysed at hourly time resolution at urban background (North Kensington, NK) and roadside (Marylebone Road, MR) sites within central London. Unlike previous work, the current study focuses on measurements during the summer providing a snapshot of contributing sources, utilising the high time resolution to improve source identification. Roadside enrichment was observed for a large number of elements associated with traffic emissions (Al, S, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Rb and Zr), while those elements that are typically from more regional sources (e.g. Na, Cl, S and K) were not found to have an appreciable increment. Positive Matrix Factorization (PMF) was applied for the source apportionment of the particle mass at both sites with similar sources being identified, including sea salt, airborne soil, traffic emissions, secondary inorganic aerosols and a Zn-Pb source. In the fine fraction, traffic emissions was the largest contributing source at MR (31.9%), whereas it was incorporated within an “urban background” source at NK, which had contributions from wood smoke, vehicle emissions and secondary particles. Regional sources were the major contributors to the coarse fraction at both sites. Secondary inorganic aerosols (which contained influences from shipping emissions and coal combustion) source factors accounted for around 33% of the PM10 at NK and were found to have the highest contributions from regional sources, including from the European mainland. Exhaust and non-exhaust sources both contribute appreciably to PM10 levels at the MR site, highlighting the continuing importance of vehicle-related air pollutants at roadside.

Airborne Wear Particles Generated from Conductor Rail and Collector Shoe Contact: Influence of Sliding Velocity and Particle Size

The mechanical wear of train components is one of the main sources of airborne particles in subway air. A certain contribution is suspected to derive from third-rail systems due to the sliding of t ...

Concentrations and Sources of Airborne Particles in a Neonatal Intensive Care Unit.

Premature infants in neonatal intensive care units (NICUs) have underdeveloped immune systems, making them susceptible to adverse health consequences from air pollutant exposure. Little is known about the sources of indoor airborne particles that contribute to the exposure of premature infants in the NICU environment. In this study, we monitored the spatial and temporal variations of airborne particulate matter concentrations along with other indoor environmental parameters and human occupancy. The experiments were conducted over one year in a private-style NICU. The NICU was served by a central heating, ventilation and air-conditioning (HVAC) system equipped with an economizer and a high-efficiency particle filtration system. The following parameters were measured continuously during weekdays with 1-min resolution: particles larger than 0.3 μm resolved into 6 size groups, CO2 level, dry-bulb temperature and relative humidity, and presence or absence of occupants. Altogether, over sixteen periods of a few weeks each, measurements were conducted in rooms occupied with premature infants. In parallel, a second monitoring station was operated in a nearby hallway or at the local nurses’ station. The monitoring data suggest a strong link between indoor particle concentrations and human occupancy. Detected particle peaks from occupancy were clearly discernible among larger particles and imperceptible for submicron (0.3–1 μm) particles. The mean indoor particle mass concentrations averaged across the size range 0.3–10 μm during occupied periods was 1.9 μg/m3, approximately 2.5 times the concentration during unoccupied periods (0.8 μg/m3). Contributions of within-room emissions to total PM10 mass in the baby rooms averaged 37–81%. Near-room indoor emissions and outdoor sources contributed 18–59% and 1–5%, respectively. Airborne particle levels in the size range 1–10 μm showed strong dependence on human activities, indicating the importance of indoor-generated particles for infant’s exposure to airborne particulate matter in the NICU.

Particle Bound Metals at Major Intersections in an Urban Location and Source Identification Through Use of Metal Markers

Air quality monitoring for Kanpur in North India, an industrial city ranked among the top ten most polluted cities worldwide, was conducted in summer 2011. Airborne particulate matter (PM) sample from six locations were analyzed for metals. Source identification conducted using metals as source markers reveals probable sources of airborne particles being vehicular emissions, industrial, and railway activity. Findings were substantiated by investigating morphological characteristics and elemental composition of PM using SEM-EDX analysis at three major sites. In addition to confirmation of results by metal marker method, SEM-EDX analysis revealed presence of sulphur (S) which highlights influence of Panki Thermal Power Plant on air quality. The study shows that high levels of metals observed in airborne particles at major intersections may pose a significant cancer risk by exposure to toxics such as Cr, Pb and Ni.

Characterization of Fine Particulate Matter Emitted from the Resuspension of Road and Pavement Dust in the Metropolitan Area of São Paulo, Brazil

Many studies have been performed in order to characterize the sources of airborne particles in the Metropolitan Area of São Paulo (MASP), in Brazil. Those studies have been based on receptor modeling and most of the uncertainties in their results are related to the emission profile of the resuspended road dust particles. In this study, we analyzed the composition of resuspended road dust particles in different environments: local streets, paved roads inside traffic tunnels, and high traffic streets. We analyzed the samples to quantify the concentrations of trace elements and black carbon. On the basis of that analysis, we developed emission profiles of the resuspended road dust that are representative of the different types of urban pavement in the MASP. This study is important given the international efforts in improving emissions factors with local characteristics, mainly in South America and other regions for which there is a lack of related information. This work presents emission profiles derived from resuspended road dust samples that are representative of the different types of urban pavement in the Metropolitan Area of São Paulo.

Size-resolved source apportionment of particulate matter in urban Beijing during haze and non-haze episodes

Abstract. Additional size-resolved chemical information is needed before the physicochemical characteristics and sources of airborne particles can be understood; however, this information remains unavailable in most regions of China due to lacking measurement data. In this study, we report observations of various chemical species in size-segregated particle samples that were collected over 1 year in the urban area of Beijing, a megacity that experiences severe haze episodes. In addition to fine particles, high concentrations of coarse particles were measured during the periods of haze. The abundance and chemical compositions of the particles in this study were temporally and spatially variable, with major contributions from organic matter and secondary inorganic aerosols. The contributions of organic matter to the particle mass decreased from 37.9 to 31.2 %, and the total contribution of sulfate, nitrate and ammonium increased from 19.1 to 33.9 % between non-haze and haze days, respectively. Due to heterogeneous reactions and hygroscopic growth, the peak concentrations of the organic carbon, cadmium and sulfate, nitrate, ammonium, chloride and potassium shifted from 0.43 to 0.65 µm on non-haze days to 0.65–1.1 µm on haze days. Although the size distributions of lead and thallium were similar during the observation period, their concentrations increased by a factor of more than 1.5 on haze days compared with non-haze days. We observed that sulfate and ammonium, which have a size range of 0.43–0.65 µm, sulfate and nitrate, which have a size range of 0.65–1.1 µm, calcium, which has a size range of 5.8–9 µm, and the meteorological factors of relative humidity and wind speed were responsible for haze pollution when the visibility was less than 10 km. Source apportionment using Positive Matrix Factorization showed six PM2.1 sources and seven PM2.1–9 common sources: secondary inorganic aerosol (25.1 % for fine particles vs. 9.8 % for coarse particles), coal combustion (17.7 % vs. 7.8 %), biomass burning (11.1 % vs. 11.8 %), industrial pollution (12.1 % vs. 5.1 %), road dust (8.4 % vs. 10.9 %), vehicle emissions (19.6 % for fine particles), mineral dust (22.6 % for coarse particles) and organic aerosol (23.6 % for coarse particles). The contributions of the first four factors and vehicle emissions were higher on haze days than non-haze days, while the reverse is true for road dust and mineral dust. The sources' contribution generally increased as the size decreased, with the exception of mineral dust. However, two peaks were consistently found in the fine and coarse particles. In addition, the sources' contribution varied with the wind direction, with coal and oil combustion products increasing during southern flows. This result suggests that future air pollution control strategies should consider wind patterns, especially during episodes of haze. Furthermore, the findings of this study indicated that the PM2.5-based data set is insufficient for determining source control policies for haze in China and that detailed size-resolved information is needed to characterize the important sources of particulate matter in urban regions and better understand severe haze pollution.

COAL-FIRED POWER PLANT AIRBORNE PARTICLES IMPACT TOWARDS HUMAN HEALTH

The explosion of global warming and climate change occurs parallel to the raise rise of earth development. These phenomena happen due to the deterioration of atmospheric environment rooted from human activity. Ranges of air pollutants had been discovered. However, this research focuses on airborne particles in particular that comes from the emissions of coal. Recently, Malaysia electricity demand is raising and leads to the diversification of its sources towards the non-renewable energy. Manjung coal-fired power plant emission had been recognised as one of the potential anthropogenic sources of airborne particles. 8-hours airborne particles sampling had been done at Manjung Power Plant in March and July 2011 with 7-hole sampler at 2 L/min air flow and cyclone sampler at 2.2 L/min airflow. This research found that total inhalable dust exceeds 96.78 %; PM10 standard of 0.15mg/m3.This study also found that the percentage ratio of respirable towards total inhalable dust is 33.49%. This study also found that, as the temperature increases, the airborne particles concentration also increases. It is believed that the smaller offers particulate higher degree of illness. Thus, it is believed, the airborne particles dissemination from its sources is affected by the climate of an environment. Whichcan be deposited into deeper part of lung and provide adverse health impact towards the public or residence of surrounding coal-fired power plant neighbourhood area, generally and coal workers, specifically.

Combining microscopy with spectroscopic and chemical methods for tracing the origin of atmospheric fallouts from mining sites

Populations living close to mining sites are often exposed to important heavy metal concentrations, especially through atmospheric fallouts. Identifying the main sources of metal-rich particles remains a challenge because of the similarity of the particle signatures from the polluted sites. This work provides an original combination of physical and chemical methods to determine the main sources of airborne particles impacting inhabited zones. Raman microspectrometry (RMS), X-ray diffraction (DRX), morphology analyses by microscopy and chemical composition were assessed. Geochemical analysis allowed the identification of target and source areas; XRD and RMS analysis identified the main mineral phases in association with their metal content and speciation. The characterization of the dominant minerals was combined with particle morphology analysis to identify fallout sources. The complete description of dust morphologies permitted the successful determination of a fingerprint of each source site. The analysis of these chemical and morphological fingerprints allowed identification of the mine area as the main contributor of metal-rich particles impacting the inhabited zone. In addition to the identification of the main sources of airborne particles, this study will also permit to better define the extent of polluted zones requiring remediation or protection from eolian erosion inducing metal-rich atmospheric fallouts.

Analysis of multivariate stochastic signals sampled by on-line particle analyzers: Application to the quantitative assessment of occupational exposure to NOAA in multisource industrial scenarios (MSIS)

In multisource industrial scenarios (MSIS) coexist NOAA generating activities with other productive sources of airborne particles, such as parallel processes of manufacturing or electrical and diesel machinery. A distinctive characteristic of MSIS is the spatially complex distribution of aerosol sources, as well as their potential differences in dynamics, due to the feasibility of multi-task configuration at a given time. Thus, the background signal is expected to challenge the aerosol analyzers at a probably wide range of concentrations and size distributions, depending of the multisource configuration at a given time. Monitoring and prediction by using statistical analysis of time series captured by on-line particle analyzersin industrial scenarios, have been proven to be feasible in predicting PNC evolution provided a given quality of net signals (difference between signal at source and background). However the analysis and modelling of non-consistent time series, influenced by low levels of SNR (Signal-Noise Ratio) could build a misleading basis for decision making. In this context, this work explores the use of stochastic models based on ARIMA methodology to monitor and predict exposure values (PNC). The study was carried out in a MSIS where an case study focused on the manufacture of perforated tablets of nano-TiO2 by cold pressing was performed.

A new method for determining the sources of airborne particles

Air quality is a major issue for humans owing to the fact that the content of particles in the atmosphere has multiple implications for life quality, ecosystem dynamics and environment. Scientists are therefore particularly interested in discovering the origin of airborne particles. A new method has been developed to model the relationship between the emission surface and the total amount of airborne particles at a given distance, employing olive pollen and olive groves as examples. A third-degree polynomial relationship between the air particles at a particular point and the distance from the source was observed, signifying that the nearest area to a point is not that which is most correlated with its air features. This work allows the origin of airborne particles to be discovered and could be implemented in different disciplines related to atmospheric aerosol, thus providing a new approach with which to discover the dynamics of airborne particles.

Spectral imaging and passive sampling to investigate particle sources in urban desert regions.

Two types of electron microscopy analyses were employed along with geographic information system (GIS) mapping to investigate potential sources of PM2.5 and PM10 (airborne particulate matter smaller than 2.5 and 10 μm, respectively) in two urbanized desert areas known to exhibit PM excursions. Integrated spectral imaging maps were obtained from scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS) analyses of 13 filters collected in Imperial Valley, California. Seven were from 24 h PM10 Federal Reference Method (FRM) samplers and six were from PM2.5 FRM samplers. This technique enabled extraction of information from particles collected on complex filter matrices, and indicated that all samples exhibited substantial proportions of crustal particles. Six Imperial PM2.5 and PM10 filters selected from unusually high-PM days exhibited more large particles (2.5-15 and 10-30 μm, respectively) than did filters from low-PM days, and were more consistent with soils analyzed from the region. High winds were present on three of the six high-PM days. One of the high-PM2.5 filters also exhibited substantial fine carbonaceous soot PM, suggesting significant contributions from a combustion source. Computer-controlled SEM/EDS (CCSEM/EDS) was conducted on PM collected with UNC Passive samplers from Phoenix, Arizona. The passive samplers showed good agreement with co-located FRM PM10 and PM2.5 measurements (μg m(-3)), and also enabled detailed individual particle analysis. The CCSEM/EDS data revealed mostly crustal particles in both the Phoenix fine and coarse PM10 fractions. GIS maps of multiple dust-related parameters confirm that both Imperial Valley and Phoenix possess favorable conditions for airborne crustal PM from natural and anthropogenic sources.

Indoor airborne particle sources and semi-volatile partitioning effect of outdoor fine PM in offices

To date, few studies have focused on PM air quality in offices, despite the fact that a lot of people spend many working hours a day in such offices. The aim of the present study is to investigate PM1 and PM2.5 in offices in Milan (Northern Italy) and in the air outside those offices. The PM samples were analyzed to determine the entity of certain compounds with possible direct or indirect adverse effects on human health: PAHs, BpA, and water soluble inorganic ions.A good correlation between outdoor and indoor PM mass concentrations emerged (R2 ∼0.87). The maximum I/O concentration ratio was 0.92, suggesting that the indoor PM level was always lower than the outdoor level. The average infiltration factor, FINF, was 0.55, showing that about a half of the outdoor PM had come indoors. The indoor-generated particles, Cig, had values ranging from 0 to 4.4 μg m−3 (<25% of the indoor PM), showing that PM indoor sources had only made a limited contribution to total indoor PM.The results of the indoor-to-outdoor comparisons for the aforementioned chemical compounds demonstrate that the offices were characterized by the absence of effective indoor sources of particulate-bound PAHs and inorganic ions, whereas Cig was around 58% of the indoor concentration for BpA. Our analysis of the FINF data pointed to the presence of a volatilization effect from PM for semi-volatile compounds like ammonium nitrate and 4- or 5-ring PAHs, which affected the measurement of their FINF. We propose the introduction of a new and simple parameter, called volatilization correction, to take account of this effect.

Characterization of fine particle emissions from incense burning

Incense burning is an important indoor source of airborne particles. In this study, the emission factors of PM 2.5 and its chemical constituents emitted from six different brands of incense sticks were determined. Controlled experiments were conducted to measure the mass concentration of PM 2.5 and to determine its chemical composition (elemental carbon (EC), organic carbon (OC), metals, and ions). Measurements showed that the emissions vary for different brands of incense sticks, with smokeless incense sticks emitting the least amount. PM 2.5 emission factors range from 0.4 (smokeless incense stick) to 44.5 mg/g. Results also show that the amount of metals emitted is highly dependent on the quantity of metals present in the incense sticks. In addition, the information obtained from the controlled experiments is used to predict the concentration of PM 2.5 at incense smoke-influenced microenvironments, such as temples and homes, in order to assess the potential indoor exposure during the course of incense burning. Comparison with indoor air quality guidelines suggests that inhalation of incense smoke can pose adverse health impacts.

A study of airborne wear particles generated from the train traffic—Block braking simulation in a pin-on-disc machine

Recently, much attention has been given to the influence of airborne particles in the atmosphere on human health. Sliding contacts are a significant source of airborne particles. In this study airborne particles from railway block brakes are studied using cast iron and composite block material on railway wheel steel. A pin-on-disc tribometer equipped with airborne particle counting instrumentation was used as experimental set-up. The result shows differences for the two tested block brake material combinations in particle size distribution, morphology and elemental content.