PM10 Fraction Research Articles

Source identification of the elemental fraction of particulate matter using size segregated, highly time-resolved data and an optimized source apportionment approach

Source emissions with high covariance degrade the performance of multivariate models, and often highly-time resolved data is needed to accurately extract the contribution of different emissions. Here, we use highly time-resolved size segregated elemental composition data to apportion the sources of the elemental fraction of PM in Zürich (May 2019–May 2020). For data collection, we have used an ambient metals monitor, Xact 625i, equipped with a sampling inlet alternating between PM 2.5 and PM 10 . By implementing interpolation and a newly proposed uncertainty estimation methodology, it was possible to obtain and use in PMF a combined dataset of PM 2.5 and PM coarse (PM 10-2.5 ) having data from only one instrument. The combination of the inlet switching system, the instrument's high time resolution, and the use of advanced source apportionment approaches yielded improved source apportionment results in terms of the number of identified sources, as the model, additionally to the diurnal and seasonal variation of the dataset, also utilizes the variation from the size segregated data. Thirteen sources of elements were identified, i.e., sea salt (5.4%), biomass burning (7.2%), construction (4.3%), industrial (3.3%), light-duty vehicles (5.4%), Pb (0.7%), Zn (0.7%), dust (22.1%), transported dust (9.5%), sulfates (15.4%), heavy-duty vehicles (17%), railway (6.6%) and fireworks (2.4%). The Covid-19 lockdown effect in PM sources in the area was also quantified. High-intensity events disproportionally affect the PMF solution, and in many cases, they are getting discarded before analysis, removing thus valuable information from the dataset. In this study, a three-step source apportionment approach was used to get a well-resolved unmixed solution when firework data points were included in the analysis. This approach can also be used for other sources and/or events with very high contributions that distort source apportionment analysis. Optimized source apportionment techniques are necessary for effective air pollution monitoring. • Combined PM 2.5 and PM coarse elemental composition data using a single instrument. • Methodology for the estimation of the uncertainty of interpolated PM elemental composition data. • Source apportionment method for the use of data that include high-intensity events. • The effect of Covid-19 lockdown to PM source contributions. • Quantification of heavy duty & low duty vehicular emissions.

Atmospheric levels, distribution, sources, correlation with meteorological parameters and other pollutants and health risk of PAHs bound in PM2.5 and PM10 in Burgas, Bulgaria – a case study

The quality of atmospheric air of Burgas city, Bulgaria was analyzed in relation to PAHs in two particulate matter fractions – 2.5 μm and 10 μm. It was found that PAHs registered in PM10 represent entirely the ones registered in PM2.5 – an indication that the particulate PAHs in ambient air of Burgas for the sampling period are associated with the fine PM fraction. The PAH compounds with highest concentrations are mainly associated with coal combustion, diesel and gasoline vehicle and biomass burning, which is further confirmed by the calculated diagnostic ratios. The combustion-derived PAHs represent on average 86.6 ± 2.8% of total PAHs concentration. The linear regression analysis showed strong and statistically meaningful correlations between PM fractions and PAHs indicating the influence of similar local events and emission sources of pollution. PM2.5 or PM10 relationships with PAHs were significant but lower correlation coefficients were observed for low-molecular weight (LMW) PAHs in comparison to middle-molecular weight (MMW) and higher-molecular weight (HMW) PAHs, due to their lower presence in particulates and higher partition in gaseous atmospheric phase. Further significant correlations were found with wind speed, solar radiation and atmospheric pressure as well as NO2 and O3 ambient concentration. The calculated excess cancer risks are twice as much as acceptable limit.

Ultrafine particles: A review about their health effects, presence, generation, and measurement in indoor environments

Human exposure to aerosols has been associated with diseases and death, reducing the population's life expectancy up to a few years. Indoor particulate matter is predominant in determining human exposure to PM because people spend most of their time indoors.Ultrafine particles (UFP) impact the human body differently from PM2.5 or PM10 fractions. Therefore, scientists cannot apply the same approach to assess the effects of UFP and PM on human health.This work summarizes the health effects, generation, and measurement of ultrafine particles in indoor environments through a literature review. When indoor particle generation is low, particle concentration indoors depends strongly on outdoor aerosols, with an indoor-to-outdoor ratio below 1. In buildings with a high indoor particle generation, the average indoor-to-outdoor UFP concentration ratio can reach 14. Combustion, electric heating, and house cleaning are the main generators of UFP indoors.Current standards for UFP assessments do not provide a solid ground for accurate and reliable measurements. Moreover, the lowest detection limit of instruments used to measure UFP concentration can be significantly different while also showing poor repeatability even among instruments with the same manufacturer and model. Consequently, data supplied by studies on UFP health effects are insufficient and inconclusive.Using ultrafine portable monitors would allow determining properly human exposure to PM0.1, but such instruments are expensive for wide use. Since there is a good correlation between UFP and NOX data, low-cost NOX sensors are good candidates to create a dense and accurate monitoring network of UFP, including indoor environments.

Long-term airborne particle pollution assessment in the city of Coyhaique, Patagonia, Chile

An air pollution assessment in a small city located in the heart of Chilean Patagonia is presented. Seven years (2014–2020) of PM concentration levels retrieved from two monitoring stations permits an evaluation of the city's pollution variability, the effect of meteorological variables and long-term trends of air pollution. The highest PM concentration levels observed during the coldest months are mainly related to an increasing emission associated with the intensive use of firewood for residential heating and cooking. The most polluted days are associated with low temperatures, low wind speed and high PM2.5/PM10 ratios, which is consistent with the predominance of local firewood sources over background emissions. A decrease in both PM fractions over time has been estimated (PM10: -4.1, CI99%: −5.7 to −2.9 and PM2.5: -2.2, CI99%: −3.5 to −1.3 μg m−3 year−1). However, the annual average PM mass concentrations in Coyhaique exceeded both national and international air quality thresholds. The city reported a percent of annual exceedances of the daily WHO guidelines of 57% for PM10 and 77% for PM2.5. These numbers highlight the serious air pollution problem of the city of Coyhaique, which exhibits air pollution levels comparable to those of many polluted megacities in the world.

Characterization of PM2.5 Mass in Relation to PM1.0 and PM10 in Megacity Seoul

This study examines the PM2.5 characteristics in Seoul in relation to those of PM1.0 and PM10. Samples were typically collected daily on filters and a few hours sampling were conducted during a few haze events (March 2007 to June 2008). Mean mass concentrations of PM1.0, PM2.5, and PM10 were 19.7 μg/m3, 26.0 μg/m3, and 48.2 μg/m3, respectively, and PM2.5 was reasonably correlated with PM1.0 (γ=0.79) and PM10 (γ=0.52). Three mass group types were mainly distinguished. Group 1 (31%): linear increase of PM1.0 with PM10 and high OC and NO3−; Group 2 (17%): PM10 considerably higher than PM1.0 and high Ca2+ and SO42−; Group 3 (52%): PM1.0 relatively more enhanced than PM10 and highest carbonaceous fraction against mass. The fine mode fraction was lowest (highest) in Group 2 (Group 3). Haze and dust episodes relating to Chinese outflows were mostly evident in Groups 1 and 2, respectively; average PM2.5 concentrations were visibly higher than in Group 3. Non-Negative Matrix Factorization analysis demonstrated that traffic-related urban primary (28%) and coal-fired industry (27%) emissions equally contributed to the PM2.5 mass, followed by aged urban secondary (19%), soil mineral (16%), and biomass combustion (10%) sources. Seasonal variations were apparent in air mass trajectories. Urban primary and coal-fired industry factors were predominant in Group 3 under stagnant conditions in the warm season and under a strong northerly wind in the cold season, respectively. However, contributions of the other three factors were higher in Groups 1 and 2. This study shows that the PM2.5 mass in Seoul is largely dependent on high concentration episodes occurring mostly in cold seasons. It also shows that local emissions contribute considerably during warm months, while the influence of Chinese outflow predominates during cold months.

Distribution and sources of SVOCs in fine and coarse aerosols in the megacity of Istanbul

Approximately 15.4 million people are continuously exposed to various air pollutants in the megacity of Istanbul. Anthropogenic activities in Istanbul generate emissions from mobile sources (i.e., vehicles, aircraft, ships, etc.) and stationary sources such as industrial and residential heating emissions. Biogenic emissions and long-range transport such as desert dust from Sahara and pollutants from Balkan countries also contribute to the local air pollution in Istanbul. In this work, fine (Dp < 2.5 μm) and coarse (Dp > 2.5 μm) particles were collected with a high-volume sampler during four seasons of the period Jan 2017 - Jan 2018. A total of 15 PAHs and 28 n-alkanes were identified and quantified with a newly developed thermal desorption – gas chromatography with mass spectrometry method (TD-GC–MS). Source analysis was performed with PAH and n-alkane diagnostic ratios, and source apportionment was performed with principal component analysis. The yearly averages of PAHs and n-alkanes in the fine fraction were 21.6 ng m−3 and 103.8 ng m−3, with daily averages of 7.1–80.8 ng m−3 and 55.3–204.2 ng m−3, respectively. Approximately 90% of the PAHs and n-alkanes were found in the fine PM fraction in this traffic site. The BaP carcinogenic (BaP-TEQ) and mutagenic (BaP-MEQ) equivalents were on average 5.47 ± 0.64 and 4.72 ± 0.8 ng m−3 in the fine fraction, respectively, and were approximately 6–7 times lower in the coarse fraction. This has important implications due to the respirable nature of fine aerosols and their longer lifetimes in the atmosphere. Multivariate analysis coupled with principal component analysis led to an important result that the organic aerosol mainly originates from two local sources: road traffic (50.4%) and shipping emissions (26.6%). The results found in this work indicate the urgent need for the application of mitigation measures to control road traffic and minimize the emissions from ships passing through the İstanbul Bosphorus.

Particulate Matter Ionic and Elemental Composition during the Winter Season: A Comparative Study among Rural, Urban and Remote Sites in Southern Italy

We present an overview of the concentrations and distributions of water-soluble ion species and elemental components in ambient particulate matter for five measurement sites in southern Italy with the aim of investigating the influence of the different site characteristics on PM levels. The sites encompass different characteristics, ranging from urban to coastal and high-altitude remote areas. PM10 and PM2.5 fractions were collected simultaneously using dual channel samplers during the winter period from November 2015 to January 2016 and analyzed for water-soluble ion species, using ion chromatography, and elemental composition, using inductively coupled plasma mass spectrometry (ICP-MS). In all sites, PM2.5 represented the higher contribution to particulate mass, usually more than two times that of the coarse fraction (PM2.5−10). At the coastal site in Capo Granitola (Western Sicily), sea salts constituted about 30% of total PM10 mass. On average, ion species accounted for 30% to 60% of total PM10 mass and 15% to 50% of PM2.5 mass. We found that secondary ion species, i.e., SO42−, NO3− and NH4+ dominated the identifiable components within both PM2.5 and PM10 fractions. The chlorine–sodium ratio was usually lower than that expected from the natural level in sea salt, evidencing aged air masses. At the monitoring site in Naples, a highly urbanized area affected by high levels of anthropogenic source emissions, an increased contribution of ammonium was found, which was imputed to the increased ammonia emissions from industrial combustion sources and road traffic. The concentrations of the investigated elements showed noteworthy differences from one site to another. The PM10 fraction was highly enriched by sources of anthropogenic origin in the samples from the most urbanized areas. In general, the enrichment factors of the elements were similar between the PM10 and PM2.5 fractions, confirming common sources for all elements.

Pollution Level, Partition and Spatial Distribution of Benzo(a)pyrene in Urban Soils, Road Dust and Their PM10 Fraction of Health-Resorts (Alushta, Yalta) and Industrial (Sebastopol) Cities of Crimea

Polycyclic aromatic hydrocarbons (PAHs), in particular benzo(a)pyrene (BaP), are priority organic pollutants coming from various anthropogenic sources. The levels of accumulation and the spatial distribution of BaP in urban soils, road dust and their PM10 particles (with a diameter of less than 10 microns) were for the first time determined for various land use zones and roads of different size in the cities of Crimea—Alushta, Yalta and Sebastopol. The average content of BaP in soils and road dust in Alushta is 60 and 97 ng/g, in Yalta—139 and 64 ng/g, in Sebastopol—260 and 89 ng/g, respectively, which considerably exceeds the background level (1 ng/g). The BaP concentrations in PM10 particles of soils and dust are up to 11 and four times higher, respectively, than the total contents; they concentrate 35–70% of amount of the pollutant. The accumulation of BaP in soils and dust depends on the type of land use and size of roads. The exceedance of BaP standards in soils and road dust indicates a hazardous environmental situation in three cities of Crimea. The most dangerous are PM10 particles, which form anomalies with extreme levels of BaP contamination.

Diversity and Source of Airborne Microbial Communities at Differential Polluted Sites of Rome

Biogenic fraction of airborne PM10 which includes bacteria, viruses, fungi and pollens, has been proposed as one of the potential causes of the PM10 toxicity. The present study aimed to provide a comprehensive understanding of the microbial community variations associated to PM10, and their main local sources in the surrounding environment in three urban sites of Rome, characterized by differential pollution rate: green area, residential area and polluted area close to the traffic roads. We combined high-throughput amplicon sequencing of the bacterial 16S rRNA gene and the fungal internal transcribed spacer (ITS) region, with detailed chemical analysis of particulate matter sampled from air, paved road surfaces and leaf surfaces of Quercus ilex. Our results demonstrated that bacterial and fungal airborne communities were characterized by the highest alpha-diversity and grouped separately from epiphytic and road dust communities. The reconstruction of source-sink relationships revealed that the resuspension/deposition of road dust from traffic might contribute to the maximum magnitude of microbial exchanges. The relative abundance of extremotolerant microbes was found to be enhanced in epiphytic communities and was associated to a progressively increase of pollution levels as well as opportunistic human pathogenicity in fungal communities.

Interannual and Seasonal Variation of Optical and Microphysical Properties of Aerosol in the Baikal Region

The paper analyzes the interannual, seasonal variations of the optical and microphysical characteristics of aerosol in the Baikal region atmosphere according to measurements using the CIMEL sun photometer of the AERONET network at Tory station and according to the data of expedition measurements using the SP-9 sun photometer on the southeastern coast of Lake Baikal from 2010 to 2020. It is shown that in recent years, there has been an increase of the average monthly aerosol optical depth (AOD) values in the summer months, which is consistent with an increase in smoke emission due to annual large-scale wildfires in the boreal forests of Siberia and Yakutia in summer. Aerosol classification was carried out based on filtration and selection of the prevailing types of aerosols by analysis of aerosol optical depth and Angstrom exponent. It was revealed that in summer, the proportion of the smoke component of the aerosol optical depth increases to 30% compared to the spring. In the presence of smoke advection, the close relationship of AOD with the concentrations of the microdispersed aerosol fraction PM10 and PM2.5 was revealed. The correlation coefficients between the concentration of particulate matter (PM10 and PM2.5) and AOD were 0.87 and 0.86, respectively.

Lung function and self-rated symptoms in healthy volunteers after exposure to hydrotreated vegetable oil (HVO) exhaust with and without particles

BackgroundDiesel engine exhaust causes adverse health effects. Meanwhile, the impact of renewable diesel exhaust, such as hydrotreated vegetable oil (HVO), on human health is less known. Nineteen healthy volunteers were exposed to HVO exhaust for 3 h in a chamber with a double-blind, randomized setup. Exposure scenarios comprised of HVO exhaust from two modern non-road vehicles with 1) no aftertreatment system (‘HVOPM+NOx’ PM1: 93 µg m−3, EC: 54 µg m−3, NO: 3.4 ppm, NO2: 0.6 ppm), 2) an aftertreatment system containing a diesel oxidation catalyst and a diesel particulate filter (‘HVONOx’ PM1: ~ 1 µg m−3, NO: 2.0 ppm, NO2: 0.7 ppm) and 3) filtered air (FA) as control. The exposure concentrations were in line with current EU occupational exposure limits (OELs) of NO, NO2, formaldehyde, polycyclic aromatic hydrocarbons (PAHs), and the future OEL (2023) of elemental carbon (EC). The effect on nasal patency, pulmonary function, and self-rated symptoms were assessed. Calculated predicted lung deposition of HVO exhaust particles was compared to data from an earlier diesel exhaust study.ResultsThe average total respiratory tract deposition of PM1 during HVOPM+NOx was 27 µg h−1. The estimated deposition fraction of HVO PM1 was 40–50% higher compared to diesel exhaust PM1 from an older vehicle (earlier study), due to smaller particle sizes of the HVOPM+NOx exhaust. Compared to FA, exposure to HVOPM+NOx and HVONOx caused higher incidence of self-reported symptoms (78%, 63%, respectively, vs. 28% for FA, p < 0.03). Especially, exposure to HVOPM+NOx showed 40–50% higher eye and throat irritation symptoms. Compared to FA, a decrement in nasal patency was found for the HVONOx exposures (− 18.1, 95% CI: − 27.3 to − 8.8 L min−1, p < 0.001), and for the HVOPM+NOx (− 7.4 (− 15.6 to 0.8) L min−1, p = 0.08). Overall, no clinically significant change was indicated in the pulmonary function tests (spirometry, peak expiratory flow, forced oscillation technique).ConclusionShort-term exposure to HVO exhaust concentrations corresponding to EU OELs for one workday did not cause adverse pulmonary function changes in healthy subjects. However, an increase in self-rated mild irritation symptoms, and mild decrease in nasal patency after both HVO exposures, may indicate irritative effects from exposure to HVO exhaust from modern non-road vehicles, with and without aftertreatment systems.

Spatial distribution, pollution characterization, and risk assessment of environmentally persistent free radicals in urban road dust from central China

Environmentally persistent free radicals (EPFRs) have aroused widespread concern due to their potential adverse health effects. Research on EPFRs in road dust is still very limited. In this study, 86 road dust samples were collected using vacuum sampling in a rapidly developing city in central China. The pollution characterization and health risk of EPFRs in the urban road dust were then systematically analyzed. The results showed the average concentrations of EPFRs in urban road dust and fraction of particle with aerodynamic diameters lower than 10 μm (PM10) were 2.24 × 1017 to 3.72 × 1019 spins·g−1 and 6.02 × 1017 to 1.41 × 1020 spins g−1, respectively. The concentrations of EPFRs in dust from expressways, arterial roads, and secondary trunk roads were significantly higher than those found in the remaining road types. The g-factors of 2.0032–2.0039 indicated that the EPFRs have consisted of oxygen-centered and carbon-centered radicals or carbon-centered radicals with nearby oxygen or halogen atoms. Moreover, three decay patterns of EPFRs were observed: a fast decay followed by a slow decay, a single slow decay, and the slowest decay. In addition, a comparative evaluation was made for probabilistic risk assessments of exposure to the EPFRs in road dust and the PM10 fraction. Compared with road dust, the probability of the number of equivalent cigarettes to exceed the 100 and 200 cigarettes for inhaling EPFRs in the PM10 fraction increased by 27.0% and 25.0%, respectively. The simulation results showed the PM10 fraction were primarily deposited in the upper respiratory tract regions (57.1%) and pulmonary regions (28.8%). The findings of this study suggest a potential risk of EPFRs in inhalable particles and provide a new insight for further exploration of the EPFRs in fine particles of road dust.

Seasonal Variability of Resuspension

Particulate air pollution in cities is caused by a variety of sources. One of the less-studied contributors is wind-induced particle resuspension. As the wind speed increases, particles are removed from surfaces. These particles cause an increase in the total concentration in the air. It is known that particles of 10-2.5 μm in size can be resuspended (PM10-2,5). Modern emission monitoring in cities also allows the monitoring of fine particles of 10, 2.5 and 1 μm in size. The size fractions can then be sorted into PM10-2,5, PM2,5-1 and PM1. When breathed in, particles of different sizes cause various serious health risks. This paper focuses on the identification of the resuspension process of different particle size fractions by a data processing method. Data measured by automatic emission monitoring are used. It is confirmed that the concentration increase can be dominated by the fraction PM10-2,5. However, a concentration increase of fractions PM2,5-1 and PM1 is also evident with increasing wind speed. Although the increase in the PM1 fraction is smaller than PM10-2,5, it is more severe due to the respiratory deposition dose. The resuspension of particles of different fractions has different behaviours during the year. PM10-2,5 particles are dominantly resuspended in the summer months. In winter, on the other hand, the proportion of PM2.5-1 and PM1 particles increases, which may be related to the heating season

Greenness alleviates the effects of ambient particulate matter on the risks of high blood pressure in children and adolescents

Both ambient particulate matter (PM) and decrease of greenness have been suggested as risk factors for high blood pressure (HBP) in children and adolescents. But most evidence were from cross-sectional studies with limited data from prospective cohorts. In this cohort study, we included 588,004 children and adolescents aged 7 to 18 years without HBP from 2005 to 2018 in Beijing (240,081) and Zhongshan (347,923) city of China. The cumulative incidence of HBP was 32.04%, and incidence rate was 14.86 per 100 person-year. After adjustment for confounders, the ten-unit increase in PM1, PM2.5, and PM10 exposure was significantly associated with 43%, 70%, and 43%- higher risks of HBP, respectively, but the 0.1-unit increase in NDVI exposure was significantly associated with a 25% lower risk of HBP. The HRs of PM1 on the HBP risk were 1.486 and 1.150 in the low and the high-level of greenness, and they were 2.635 and 2.507 for PM2.5, and for PM10 1.367 and 1.702 in the two groups. The attributable fraction (AFs) of PM1, PM2.5, and PM10 on HBP incidents were 13.74%, 40.08%, and 15.47% in the low-level of greenness, which simultaneously was higher than those in the high-level of greenness (AF = 4.62%, 17.28%, and 9.96%). The exposure to higher ambient PM air pollution and lower greenness around schools were associated with a higher risk of HBP in children and adolescents, but higher greenness alleviated the adverse effects of ambient PM1 and PM2.5 on the HBP risks. Our findings highlighted a synergic strategy in preventing childhood HBP by decreasing air pollution reduction and improving greenness concurrently.

A global observational analysis to understand changes in air quality during exceptionally low anthropogenic emission conditions.

This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015-2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O3 and the total gaseous oxidant (OX=NO2+O3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015-2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO2 and NOx concentrations and peoples' mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO2 and between 30% and 40% in mean PM2.5 concentrations over 2020 full lockdown compared to the same period in 2015-2019. However, PM2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO2/CO ratio). Some Chinese cities showed similar increases in PM2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of ~70%. The SO2 anomalies were negative for 2020 compared to 2015-2019 (between ~25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to ~40%. The NO2/CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO2 decrease due to the general reduction in mobility (ratio of ~60%). Analysis of the total oxidant (OX=NO2+O3) showed that primary NO2 emissions at urban locations were greater than the O3 production, whereas at background sites, OX was mostly driven by the regional contributions rather than local NO2 and O3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required.

Personal exposure to particulate matter and heart rate variability among informal electronic waste workers at Agbogbloshie: a longitudinal study

BackgroundInformal electronic waste recycling activities are major contributors to ambient air pollution, yet studies assessing the effects or relationship between direct/continuous exposure of informal e-waste workers to particulate matter and cardiovascular function are rare.MethodsRepeated measurements of fractions of PM2.5, PM10–2.5, and PM10 in personal air of informal e-waste workers, (n = 142) and a comparable group (n = 65) were taken over a period of 20 months (March 2017 to November, 2018). Concurrently, 5-min resting electrocardiogram was performed on each participant to assess resting heart rate variability indices. Linear mixed-effects models were used to assess the association between PM fractions and cardiac function.ResultsSDNN, RMSSD, LF, HF and LH/HF ratio were all associated with PM. Significant associations were observed for PM2.5 and Mean NN (p = 0.039), PM10 and SDNN (p = 0.035) and PM 10–2.5 and LH/HF (p = 0.039). A 10 μg/m3 increase in the concentrations of PM 2.5, PM10–2.5, and PM10 in personal air was associated with reduced HRV indices and increased resting HR. A 10 μg/m3 per interquartile (IQR) increase in PM10–2.5 and PM10, decreased SDNN by 11% [(95% CI: − 0.002- 0.000); (p = 0.187)] and 34% [(95% CI: − 0.002-0.001); (p = 0.035)] respectively. However, PM2.5 increased SDNN by 34% (95% CI: − 1.32-0.64); (p = 0.493). Also, 10 μg/m3 increase in PM2.5, PM10–2.5 and PM10 decreased RMSSD by 27% [(− 1.34–0.79); (p = 0.620)], 11% [(− 1.73, 0.95); (p = 0.846)] and 0.57% [(− 1.56–0.46); (p = 0.255%)].ConclusionInformal e-waste workers are at increased risk of developing cardiovascular disease from cardiac autonomic dysfunction as seen in reduced HRV and increased heart rate.

Impact of vehicular movement on road dust resuspension and spatiotemporal distribution of particulate matter during construction activities

This paper presents the characteristics of ambient particulate matter (PM), resuspendable road dust and PM mass deposition in the human respiratory tract during preconstruction and construction phases. PM Emission Rates (PMER) due to resuspension and spatiotemporal distribution were estimated and compared on construction roads (CR) and non-construction roads (NCR) for both phases. The construction phase monitoring results demonstrated that the silt load (SL) and PMER at CR (SL = 26–47 g/m2, PM10ER = 18.1–43.8 g/VKT, PM2.5ER = 4.3–10.6 g/VKT) were significantly high when compared to NCR (SL = 3.0–12.5 g/m2, PM10ER = 0.3–7.5 g/VKT, PM2.5ER = 0.1–1.8 g/VKT). Preconstruction phase results showed 15 to 20 times lesser values. Spatial and temporal variation studies showed that maximum PM concentrations (PM10 = 270.1, PM2.5 = 71.8, PM1 = 56.3 μg/m3) were found during night at construction roads due to the movement of heavy-duty vehicles carrying excavated earth overnight. Between 0 and 100 m length of road on either side of the construction sites, average PM10 concentrations were greater than 250 μg/m3. Similarly, for distance between 100 and 200 m, 200–400 m and 400–500 m, the PM10 values ranged between 200 and 250 μg/m3, 150–200 μg/m3 and 100–150 μg/m3 respectively. The current study results clearly indicated that resuspension of road dust due to movement of heavy duty trucks highly influence the PM concentrations in the surrounding environment of a construction site. The MPPD model results indicated that the total deposition fraction of PM10 in construction workers airway during the construction phase was 74–78%, followed by PM2.5(23–54%) and PM1(20–25%). Integration of sustainable practices, use of pollution control technologies and implementation of policies at a local scale are the way forward to mitigate the pollution from construction activities.

Comparison of PM10 Sources at Traffic and Urban Background Sites Based on Elemental, Chemical and Isotopic Composition: Case Study from Krakow, Southern Poland

In large urban agglomerations, car traffic is one of the main sources of particulate matter. It consists of particulate matter directly generated in the process of incomplete liquid fuel burning in vehicle engine, secondary aerosols formed from exhaust gaseous pollutants (NOx, SO2) as well as products of tires, brake pads and pavement abrasion. Krakow is one of the cities in Europe with the highest concentrations of particulate matter. The article presents the results of combined elemental, chemical and isotopic analyses of particulate matter PM10 at two contrasting urban environments during winter and summer seasons. Daily PM10 samples were collected during the summer and winter seasons of 2018/2019 at two stations belonging to the network monitoring air quality in the city. Mean PM10 concentrations at traffic-dominated stations were equal to 35 ± 7 µg/m3 and 76 ± 28 µg/m3 in summer and winter, respectively, to be compared with 25.6 ± 5.7 µg/m3 and 51 ± 25 µg/m3 in summer and winter, respectively, recorded at the urban background station. The source attribution of analyzed PM10 samples was carried out using two modeling approaches: (i) The Positive Matrix Factorization (PMF) method for elemental and chemical composition (concentrations of elements, ions, as well as organic and elemental carbon in daily PM10 samples), and (ii) Isotope Mass Balance (IMB) for 13C and 14C carbon isotope composition of carbonaceous fraction of PM10. For PMF application, five sources of particulate matter were identified for each station: fossil fuel combustion, secondary inorganic aerosols, traffic exhaust, soil, and the fifth source which included road dust, industry, construction work. The IMB method allowed the partitioning of the total carbon reservoir of PM10 into carbon originating from coal combustion, from biogenic sources (natural emissions and biomass burning) and from traffic. Both apportionment methods were applied together for the first time in the Krakow agglomeration and they gave consistent results.

Insights into Elemental Composition and Sources of Fine and Coarse Particulate Matter in Dense Traffic Areas in Toronto and Vancouver, Canada.

Traffic is a significant pollution source in cities and has caused various health and environmental concerns worldwide. Therefore, an improved understanding of traffic impacts on particle concentrations and their components could help mitigate air pollution. In this study, the characteristics and sources of trace elements in PM2.5 (fine), and PM10-2.5 (coarse), were investigated in dense traffic areas in Toronto and Vancouver, Canada, from 2015–2017. At nearby urban background sites, 24-h integrated PM samples were also concurrently collected. The PM2.5 and PM10-2.5 masses, and a number of elements (i.e., Fe, Ba, Cu, Sb, Zn, Cr), showed clear increases at each near-road site, related to the traffic emissions resulting from resuspension and/or abrasion sources. The trace elements showed a clear partitioning trend between PM2.5 and PM10-2.5, thus reflecting the origin of some of these elements. The application of positive matrix factorization (PMF) to the combined fine and coarse metal data (86 total), with 24 observations at each site, was used to determine the contribution of different sources to the total metal concentrations in fine and coarse PM. Four major sources were identified by the PMF model, including two traffic non-exhaust (crustal/road dust, brake/tire wear) sources, along with regional and local industrial sources. Source apportionment indicated that the resuspended crustal/road dust factor was the dominant contributor to the total coarse-bound trace element (i.e., Fe, Ti, Ba, Cu, Zn, Sb, Cr) concentrations produced by vehicular exhaust and non-exhaust traffic-related processes that have been deposited onto the surface. The second non-exhaust factor related to brake/tire wear abrasion accounted for a considerable portion of the fine and coarse elemental (i.e., Ba, Fe, Cu, Zn, Sb) mass at both near-road sites. Regional and local industry contributed mostly to the fine elemental (i.e., S, As, Se, Cd, Pb) concentrations. Overall, the results show that non-exhaust traffic-related processes were major contributors to the various redox-active metal species (i.e., Fe, Cu) in both PM fractions. In addition, a substantial proportion of these metals in PM2.5 was water-soluble, which is an important contributor to the formation of reactive oxygen species and, thus, may lead to oxidative damage to cells in the human body. It appears that controlling traffic non-exhaust-related metals emissions, in the absence of significant point sources in the area, could have a pronounced effect on the redox activity of PM, with broad implications for the protection of public health.

Исследование и анализ источников выделения респирабельной фракции пыли на угольных разрезах

At the deposits of the Krasnoyarsk Territory, the actual concentration of the suspended dust is 60–83 mg/m3. The search for efficient ways of reducing dust emission and dust suppression remains an urgent task, since fine dust has a negative effect on the health of enterprise employees and on mining equipment reducing its service life. Full-scale measurements were conducted related to the dust content and dispersed composition of the aerosols. The dust content was measured by counting method with the use of CEM DT-9880 dust particle counter. The measurements were conducted at the points located at different distances from the road of the section. The content of the most dangerous fraction PM2.5 was 48 % of the total amount of fine dust or 30–40 mg/m3, while the maximum permissible concentration for this fraction is 0.16 mg/m3. The employees who constantly work near the automotive haul roads and the ruins of an exploded rock mass are exposed to the strongest effects of dust emissions on the respiratory organs. To reduce the dust load on the employees of the mining enterprise, it is most appropriate to deal primarily with the dust emitted from the open pit roads, since this will help to reduce the dust load by 30–40 %. The permissible length of service for the operator of the loading equipment of one of the open-pit mines of the Krasnoyarsk Territory was calculated: it will be 9 years, and not 17, as was obtained earlier — without considering the actual content of the respirable dust. With the most rational parameters of drilling and blasting operations and using all methods to reduce dust formation, it is possible to reduce the dust emission by 15–20 %.