1. |
- Hallquist, Mattias, 1969, et al.
(författare)
-
Photochemical smog in China: scientific challenges and implications for air-quality policies
- 2016
-
Ingår i: National Science Review. - : Oxford University Press (OUP). - 2095-5138 .- 2053-714X. ; 3:4, s. 401-403
-
Tidskriftsartikel (refereegranskat)abstract
- In large areas of China severe air pollution events pose a significant threat to human health, ecosystems and climate. Current reduction of primary emissions will also affect secondary pollutants such as ozone (O3) and particulate matter (PM), but the magnitude of the effects is uncertain. Major scientific challenges are related to the formation of O3 and secondary particulate matter including Secondary Organic Aerosols (SOA). Large uncertainties also remain regarding the interactions of soot, SOA and O3 under the influence of different SO2, NOX and VOC concentrations. To improve the understanding of these secondary atmospheric interactions in China, scientific areas of central importance for photochemically induced air pollutants have been identified. In addition to the scientific challenges, results from research need to be synthesized across several disciplines and communicated to stakeholders affected by air pollution and to policy makers responsible for developing abatement strategies. Development of these science-policy interactions can benefit from experience gained under the UN ECE Convention on Long Range Transboundary Air Pollution (LRTAP)
|
|
2. |
- Adeyemi, Adewale, et al.
(författare)
-
Particulate Matter (PM2.5) Characterization, Air Quality Level and Origin of Air Masses in an Urban Background in Pretoria
- 2022
-
Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 83:1, s. 77-94
-
Tidskriftsartikel (refereegranskat)abstract
- Several sources have been identified as contributing to the concentration of ambient fine particulate matter, which has been associated to a variety of health issues. The chemical characteristics and sources of trace elements in PM2.5, as well as the air quality index, were investigated in this study. Twenty four-hour fine aerosol particles were collected in an urban area in Pretoria, South Africa, from April 2017 to April 2018. Eighteen trace elements were determined using an XEPOS 5 energy-dispersive X-ray fluorescence (EDXRF) spectrometer, while black and organic carbon were estimated using an optical transmissometer from the samples collected. The HYPLIT model (version 4.9) was used to estimate air mass trajectories. Health risk was calculated by comparing it to the World Health Organization's air quality index (AQI). The overall mean PM2.5 concentration of the collected sample equals 21µg/m3. Majority of PM2.5 exceedances were reported during mid-autumn and winter seasons, as compared to daily WHO guidelines and South African standards. S had the highest concentrations, greater than 1µg/m3. Ni, Se, Br and Sb showed they were extremely enriched, (EF > 10) and suggestive of anthropogenic or non crustal origin The 24-h PM, soot, BC and OC were significantly different by the geographical origin of air masses (p < 0.05). The AQI showed that 70% of the samples showed levels above the AQI range of good and healthy air. The findings include details on the concentration, composition, and potential sources of fine PM2.5, which is essential for policy formulation and mitigation strategies in South Africa’s fight against air pollution.
|
|
3. |
- Adeyemi, Adewale, et al.
(författare)
-
Source apportionment of fine atmospheric particles using positive matrix factorization in Pretoria, South Africa
- 2021
-
Ingår i: Environmental Monitoring & Assessment. - : Springer Science and Business Media LLC. - 0167-6369 .- 1573-2959. ; 193:11
-
Tidskriftsartikel (refereegranskat)abstract
- In Pretoria South Africa, we looked into the origins of fine particulate matter (PM2.5), based on one-year sampling campaign carried out between 18 April 2017 to 17 April 2018. The average PM2.5 concentration was 21.1± 15.0 µg/m3 (range 0.7 - 66.8 µg/m3), with winter being the highest and summer being the lowest. The XEPOS 5 Energy dispersive X-ray fluorescence (EDXRF) spectroscopy was used for elemental analysis, and the US EPA PMF 5.0 program was used for source apportionment. The sources identified includes fossil fuel combustion, soil dust, secondary sulphur, vehicle exhaust, road traffic, base metal/pyrometallurgical, coal burning. Coal burning and secondary sulphur were significantly higher in winter and contributed more than 50% of PM2.5 sources. The HYSPLIT model was used to calculate the air mass trajectories (version 4.9). During the one-year research cycle, five transportation clusters were established. North Limpopo (NLP), Eastern Inland (EI), Short-Indian Ocean (SIO), Long-Indian Ocean (LIO) and South Westerly-Atlantic Ocean (SWA). Local and transboundary origin accounted for 85%, while 15% were long-range transport. Due to various anthropogenic activities such as biomass burning and coal mining, NLP clusters were the key source of emissions adding to the city's PM rate. In Pretoria, the main possible source regions of PM2.5 were discovered to be NLP and EI. Effective control strategies designed at reducing secondary sulphur, coal burning, and fossil fuel combustion emissions at Southern African level and local combustion sources would be an important measure to combat the reduction of ambient PM2.5 pollution in Pretoria.
|
|
4. |
- Alfeus, A., et al.
(författare)
-
Inhalation health risk assessment of ambient PM2.5 and associated trace elements in Cape Town, South Africa
- 2022
-
Ingår i: Human and Ecological Risk Assessment. - : Informa UK Limited. - 1080-7039 .- 1549-7860. ; 28:8, s. 917-929
-
Tidskriftsartikel (refereegranskat)abstract
- Few human health risk assessment studies of air pollution exist in Africa. This study used the US EPA health risk framework to investigate the human health risks due to inhalation exposure to ambient PM2.5 and some of its trace element composition (Cl, Si, and Ti) in Cape Town, South Africa, for 12 months (April 2017 to April 2018). The safe average daily dose was determined using the yearly WHO guideline and South African ambient air quality standard for PM2.5 and the US EPA regional screening levels for trace elements. The average yearly PM2.5 concentration (13 mu g/m(3)) was above the yearly WHO guideline (5 mu g/m(3)), but below the yearly South African standard (20 mu g/m(3)). The average yearly PM2.5 concentration posed a low risk to adults (Hazard Quotient = 0.66) compared to infants (HQ = 2.13) and children (HQ =1.96). Cl posed health risks to all age groups (HQ > 1). The study concludes that PM2.5 and its trace element components pose adverse health effects to all population age groups. The toxicity of PM2.5 depends on its composition; hence this study recommends a source apportionment study to quantify the source contributions and inform the right abatement strategies.
|
|
5. |
- Alfeus, Anna, et al.
(författare)
-
PM2.5 in Cape Town, South Africa: Chemical characterization and source apportionment using dispersion-normalised positive matrix factorization
- 2024
-
Ingår i: Atmospheric Pollution Research. - 1309-1042. ; 15:3
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding fine particulate matter (PM2.5) composition and sources is beneficial to improving visibility, addressing climate change, and mitigating poor air quality and related public health effects. Source apportionment techniques have been instrumental in evaluating the impact of sources and secondary processes on the ambient PM2.5 concentrations in receptor areas. Positive Matrix Factorization (PMF) is now the most commonly used tool due to its ability to provide mixture resolution based on available PM2.5 compositional data. Sampling and analysis of PM2.5 was conducted in Cape Town, South Africa from April 2017 to April 2018. The resulting data were dispersion normalized to address the modifications of the source concentrations resulting from the varying dispersion conditions and thereby permit dispersion normalized PMF (DN-PMF) to be employed. DN-PMF quantified the 6 sources as 2-stroke vehicles/galvanizing industries (16.8%); soil/road dust (12.3%); sulphate/marine diesel (3.6%), traffic (15.7%), sea salt (21.8%), and heating/biomass burning/cooking (15.7%). In addition, air mass back trajectory analysis using the Hybrid Single Particle Lagrangian Trajectory (HYSPLIT) model identified long-range transport pathways to Cape Town. The HYSPLIT results showed air masses from the Atlantic SSW (6%), Atlantic SW (24%), Indian Ocean (31%), and Atlantic WSW (39%) influence air quality. The primary sources affected by the transport clusters were heating, 2-stroke vehicles/galvanizing, road and soil dust, and traffic emissions. These results show that reducing emissions from the local sources will improve air quality.
|
|
6. |
- Amin, Mohammed A., et al.
(författare)
-
Elemental Variability of PM2.5 Aerosols in Historical and Modern Areas of Jeddah, Saudi Arabia
- 2022
-
Ingår i: Atmosphere. - : MDPI AG. - 2073-4433. ; 13:12
-
Tidskriftsartikel (refereegranskat)abstract
- Air particulate matter with a diameter of 2.5 µm (PM2.5) were assembled for a whole year from the historical Jeddah district. Additional PM2.5 aerosols were collected during the autumn and winter seasons from another newly constructed district in Jeddah city (Alnaeem). The annual concentration of the total mass of the PM2.5 aerosols from the historical Jeddah site was found to be 43 ± 6 µg/m3. In addition, the average of the total mass concentration at the Alnaeem site was 61 ± 14 µg/m3. These values were greater than the annual mass concentration of the air quality standards of the European Commission (25 µg/m3) and the World Health Organization (10 µg/m3). The elemental analysis of the collected fine atmospheric aerosols was achieved by energy dispersive X-ray fluorescence (EDXRF) with three secondary targets (CaF2, Ge, and Mo). Quantitative elemental analyses of twenty-two (22) elements were achieved starting from the low atomic number element (Na) up to the high atomic number element (Pb). Although the historical Jeddah site is not well organized, the elemental concentrations and total mass concentrations were lower than those of the other site. The statistical analyses including enrichment factors, correlation analysis, and the principal component analysis revealed more information about the source identification of the PM2.5 aerosols collected from both locations. It was recognized that the elements Al, Si, K, Ca, Ti, Mn, Fe, Rb, and Sr originated from a natural source. On the other hand, the elements Ta, Br, Pb, Sc, Ni, Cu, Zn, and S originated from anthropogenic sources. Finally, the elements Na, Cl, and Br came mainly from the sea spray source.
|
|
7. |
- Amin, Mohammed A., et al.
(författare)
-
Non-Covalent Functionalization of Graphene Oxide-Supported 2-Picolyamine-Based Zinc(II) Complexes as Novel Electrocatalysts for Hydrogen Production
- 2022
-
Ingår i: Catalysts. - : MDPI AG. - 2073-4344. ; 12:4
-
Tidskriftsartikel (refereegranskat)abstract
- Three mononuclear 2-picolylamine-containing zinc(III) complexes viz [(2-PA)2ZnCl]2(ZnCl4)] (Zn1), [(2-PA)2Zn(H2O)](NO3)2] (Zn2) and [Zn(2-PA)2(OH)]NO3] (Zn3) were synthesized and fully characterized. Spectral and X-ray structural characteristics showed that the Zn1 complex has a square-pyramidal coordination environment around a zinc(II) core. The hydroxide complex Zn3 was non-covalently functionalized with few layers of graphene oxide (GO) sheets, formed by exfoliation of GO in water. The resulting Zn3/GO hybrid material was characterized by FT-IR, TGA-DSC, SEM-EDX and X-ray powder diffraction. The way of interaction of Zn3 with GO has been established through density functional theory (DFT) calculations. Both experimental and theoretical findings indicate that, on the surface of GO, the complex Zn3 forms a complete double-sided adsorption layer. Zn3 and its hybrid form Zn3/GO have been individually investigated as electrocatalysts for the hydrogen evolution reaction. The hybrid heterogenized form Zn3/GO was supported on glassy carbon (GC) with variable loading densities of Zn3 (0.2, 0.4 and 0.8 mg cm−2) to form electrodes. These electrodes have been tested as molecular electrocatalysts for the hydrogen evolution reaction (HER) using linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) in 0.1 M KOH. Results showed that both GC-Zn3 and GC-Zn3/GO catalysts for the HER are highly active, and with increase of the catalyst’s loading density, this catalytic activity enhances. The high catalytic activity of HER with a low onset potential of −140 mV vs. RHE and a high exchange current density of 0.22 mA cm−2 is achieved with the highest loading density of Zn3 (0.8 mg cm−2). To achieve a current density of 10 mA cm−2, an overpotential of 240 mV was needed.
|
|
8. |
- Amin, M. A., et al.
(författare)
-
Synthesis of Cyano-Benzylidene Xanthene Synthons Using a Diprotic Brønsted Acid Catalyst, and Their Application as Efficient Inhibitors of Aluminum Corrosion in Alkaline Solutions
- 2022
-
Ingår i: Molecules. - : MDPI AG. - 1420-3049. ; 27:17
-
Tidskriftsartikel (refereegranskat)abstract
- Novel cyano-benzylidene xanthene derivatives were synthesized using one-pot and condensation reactions. A diprotic Brønsted acid (i.e., oxalic acid) was used as an effective catalyst for the promotion of the synthesis process of the new starting xanthene–aldehyde compound. Different xanthene concentrations (ca. 0.1–2.0 mM) were applied as corrosion inhibitors to control the alkaline uniform corrosion of aluminum. Measurements were conducted in 1.0 M NaOH solution using Tafel extrapolation and linear polarization resistance (LPR) methods. The investigated xanthenes acted as mixed-type inhibitors that primarily affect the anodic process. Their inhibition efficiency values were enhanced with inhibitor concentration, and varied according to their chemical structures. At a concentration of 2.0 mM, the best-performing studied xanthene derivative recorded maximum inhibition efficiency values of 98.9% (calculated via the Tafel extrapolation method) and 98.4% (estimated via the LPR method). Scanning electron microscopy (SEM) was used to examine the morphology of the corroded and inhibited aluminum surfaces, revealing strong inhibitory action of each studied compound. High-resolution X-ray photoelectron spectroscopy (XPS) profiles validated the inhibitor compounds’ adsorption on the Al surface. Density functional theory (DFT) and Monte Carlo simulations were applied to investigate the distinction of the anticorrosive behavior among the studied xanthenes toward the Al (111) surface. The non-planarity of xanthenes and the presence of the nitrile group were the key players in the adsorption process. A match between the experimental and theoretical findings was evidenced. © 2022 by the authors.
|
|
9. |
- Badawi, Ali, et al.
(författare)
-
Exploring the structural and optical properties of FeS filled graphene/PVA blend for environmental-friendly applications
- 2021
-
Ingår i: Journal of Polymer Research. - : Springer Science and Business Media LLC. - 1022-9760 .- 1572-8935. ; 28
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, the role of iron sulfide (FeS) content on the structural and optical properties of graphene/polyvinyl alcohol (Gr/PVA) blend has been examined for environmental-friendly applications. Gr/PVA blend filled with FeS (0 to 10 wt%) were equipped using the casting technique. The prepared samples were studied via a scanning electron microscope, X-ray diffractometer, FT-IR and UV–visible-NIR spectrophotometers. XRD analysis shows that the crystallinity increases with increasing FeS concentration in the host Gr/PVA blend. UV–visible-NIR analysis shows that the direct optical bandgap of composite blends shrinks from 5.37 to 4.68eV as FeS content is increased to 10 wt%. Also, it confirms that the refractive index and optical conductivity of Gr/PVA blend could be significantly enhanced via FeS filling. FeS filled Gr/PVA blends are recommended eco-friendly applications.
|
|
10. |
- Bernhardt, J, et al.
(författare)
-
CASE Needs Analysis. Summary. Findings on Competencies for Sustainability-driven Entrepreneurship. Based on interviews with partners from sustainability-driven enterprises and universities.
- 2016
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The report represents the main outputs of the needs analysis of work package 1 (WP1) within the CASE project. The specific aim of the report and WP1 is to summarize concrete needs and necessary competencies for sustainability-driven entrepreneurship. For this purpose a qualitative research approach was chosen to bring together perspectives of enterprises and universities concerning a future collaboration as a possible starting-point for a long-lasting multistakeholder network. Furthermore an analysis of best practice examples was necessary in order to create synergies and use existing knowledge and good experiences of teaching towards sustainability-driven entrepreneurship. As the results show, both, companies and universities, are highly aware of the huge challenges for society, economy and natural environment on a global and regional level. That calls for integrated, holistic approaches and for comprehensive socio-economic transformation processes, involving various stakeholders from entrepreneurial, societal and educational contexts. As disciplinary analysis quickly reach their limits, research and practice for sustainability-driven entrepreneurship require comprehensive and integrated approaches. Multistakeholder networks could provide the right learning environments for complex sustainability issues.
|
|
11. |
|
|
12. |
- Biberhofer, P, et al.
(författare)
-
Joint CASE Report on Content and Methods for the Joint Master Program on Sustainability-driven Entrepreneurship
- 2016
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The CASE project develops a joint master program on sustainability-driven entrepreneurship in a university-business knowledge alliance. However, it is not only for the development of the master program that university opens up to consider and integrate further stakeholder perspectives into the process. The future students shall learn in a transdisciplinary learning environment, steadily researching and integrating real-world needs and perspectives to develop competencies that enable them to solve complex sustainability-problems in their further careers. In the CASE project, we aim to avoid the indicated gap between sustainability-oriented, real-world contents and not corresponding pedagogical frameworks. We connect the development of contents and methods in the two interlinked work packages 3 and 4 in terms of process and outcomes (see Figure 1 for an overview of the WPs that contribute to the development of the master program). WP 3 is focusing on relevant content areas for the master program and WP 4 is analyzing innovative methods to foster competencies of sustainability-driven entrepreneurship. The output of the two WPs is this joint report describing the joint development process, giving background information on relevant content areas for sustainability-driven entrepreneurship and adequate teaching and learning approaches. In the course of the development process of WP 3 and WP 4 we considered different regional requirements and needs of the universities that are part of the CASE consortium and further stakeholders via participatory multi-stakeholder workshops. In chapter 1.3 we describe this process in detail and particularly elaborate on the multi-stakeholder approach chosen in the CASE project. This development process first covered clustering relevant topics to thematic areas, then structuring these into modules and courses with various teaching formats. Finally, we added recommendations for concrete teaching and learning methods. The report outlines modules for a master program that are designed to foster competencies of sustainability-driven entrepreneurship. Since the overarching aim of the CASE project is to develop a joint master program that can be adopted by various European universities, we are ambitious to create modules which are adaptable and can flexibly be implemented in different regional contexts and under differing conditions of universities. With this report, we are sharing our knowledge and experiences gained so far to make them accessible to HEIs, company partners and all other stakeholders interested in the topic of sustainability-driven entrepreneurship and in innovative teaching and learning methods.
|
|
13. |
- Boman, Antonia, et al.
(författare)
-
Antibodies against citrullinated peptides are associated with clinical and radiological outcomes in patients with early rheumatoid arthritis : a prospective longitudinal inception cohort study
- 2019
-
Ingår i: RMD Open. - : BMJ Publishing Group Ltd. - 2056-5933. ; 5:2
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Anticitrullinated peptide antibody (ACPA) responses for 22 citrullinated peptides in patients with early rheumatoid arthritis (RA) were analysed and related to radiological and clinical outcome during the first 2 years in a prospective inception cohort.Methods: The ACPA reactivities were assessed in 1022 patients with early RA (symptoms <12 months) using the custom-made microarray chip (Thermo Fisher Scientific, Uppsala, Sweden) in a prospective longitudinal study of observational assessments of Disease Activity Score (DAS28 and its components) and radiology during the first 24 months, accounting for the treatment.Results: Frequency of ACPA reactivities varied between 13.3% and 63.1%. Of the anticyclic citrullinated peptide-2 (anti-CCP2) antibody-negative patients, ACPA reactivities were positive in 32.6%. Smoking, human leucocyte antigen-shared epitope (HLA-SE), anti-CCP2/rheumatoid factor, protein tyrosine phosphatase non-receptor type 22 (1858C/T) and DAS28 were significantly associated with number of ACPA reactivities. The ACPA reactivities modified differently the development of DAS28 over 24 months (identified using trajectories). Anti-Filaggrin307-324, anti-hnRNP (Peptide)-Z1 and anti-F4-CIT-R antibodies anticipated lower DAS28 values (p<0.01–0.05), while positivity for anti-Fibrinogen(Fib)β62-78(74), and anti-Fibα563-583 predicted higher DAS28 (p<0.01 both). Interaction between anti-Fibß36-52, anti-Pept-5 and anti-Bla-26 antibodies, respectively, and DAS28 during 24 months decreased significantly the DAS28 values (p<0.01–0.05). Corticosteroids and biologicals were related to DAS28-area under the curve and Larsen score 24 months. Anti-vimentin2-17 antibodies remained significantly associated with Larsen score at baseline and 24 months, respectively, and radiological progression, besides biologicals at 24 months adjusted for sex and age.Conclusions: Several ACPA reactivities modified significantly the DAS28 development during the first 24 months and were significantly associated with Larsen score at baseline, 24 months and radiological progression.
|
|
14. |
- Boman, Johan, 1955, et al.
(författare)
-
A tentative study of urban and suburban fine particles (PM2.5) collected in Ouagadougou, Burkina Faso
- 2009
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539.
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to determine the mass, black carbon (BC), and elemental concentrations in fine particles (PM2.5) and their variations at two sites in Ouagadougou, the capital city of Burkina Faso. The weather situation in Ouagadougou during the field campaign was dominated by high pressure with variable cloudiness and no precipitation. Diurnal temperatures varied between 19 and 38 °C and relative humidity between 10 and 60%. Winds in Ouagadougou were generally coming in from the north, showing a diurnal pattern with gusts of up to 6 m/s during daytime, while evenings and nights were calmer with very stable atmospheric conditions. However, during part of this field campaign, a period of nighttime moderately stable atmospheric conditions occurred with increased wind speed and more easterly winds. Cyclones were used for the PM2.5 particle collection at both sites. The elemental analysis was done using energy dispersive x-ray fluorescence (EDXRF) spectroscopy. Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, Sr, and Pb were identified and quantified in most of the samples. The particle mass concentration was 27-164 µg/m3 while BC varied between 1.3 and 8.2 µg/m3. No influence of leaded gasoline was found. Soil dust was identified as a major component of the particles, which was confirmed by comparing with the elements in a soil sample. A significant difference in elemental, BC, and mass concentrations was seen between periods with very stable and moderately stable atmospheric conditions. Copyright © 2009 John Wiley & Sons, Ltd.
|
|
15. |
- Boman, Johan, 1955
(författare)
-
Analysis of urban aerosol paricles by XRF
- 2009
-
Ingår i: Spectroscopy Europe. - 0966-0941. ; 21:6, s. 11-14
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Urban pollution is a significant problem throughout the world. analysis of aerosol particles can give important information on theri origin, leading to better control measures. Trace element analysis of urban aerosol particles using X-ray fluorescence spectrometry is described in this article.
|
|
16. |
- Boman, Johan, 1955, et al.
(författare)
-
ASSESSING THE ENVIRONMENT WITH X-RAY FLUORESCENCE
- 2011
-
Ingår i: Advances in X-ray Analysis. - 0376-0308. ; 54, s. 266-279
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we will introduce the general benefits of X-Ray Fluorescence spectrometry (XRF) for assessing the condition of the outer environment, especially where ambient aerosol particles are causing environmental disturbances. Examples from recent environmental studies are presented, and energy dispersive XRF is concluded to be a powerful, nondestructive yet easily applicable tool to supply detailed elemental information of particles collected in different applications. The further development and future potential of the method for detailed analysis of aerosol particles are discussed.
|
|
17. |
- Boman, Johan, 1955, et al.
(författare)
-
Eco-labelling of courses and programs at University of Gothenburg
- 2013
-
Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 48, s. 48-53
-
Tidskriftsartikel (refereegranskat)abstract
- For several years, the University of Gothenburg has been classifying and eco-labelling its courses and programs according to the wide definition of sustainable development found in the Swedish Higher Education Act (Chapter 1, Section 5). The objective of this labelling, which corresponds to the ISO 14024:2009 standard, is primarily to guide students in their selection of courses and programs. Two different eco-labels are used. Courses and programs that primarily or partly include issues related to ecological, economic or social sustainable development have different labels. The result shows that the proportion of courses and programs that are eco-labelled is increasing over the years and currently approximately 30% of the courses and programs are eco-labelled. Studies have shown that the eco-labelling of university courses and programs is still new and many university lecturers are uncomfortable with defining sustainable development within their subject area. University of Gothenburg has started a course to train university lecturers on how to use good examples, find relevant literature and through dialogue, get help on how sustainable development can be integrated into various subject areas.
|
|
18. |
- Boman, Johan, 1955, et al.
(författare)
-
Elemental characterization of aerosols in urban and rural locations in Bangladesh
- 2005
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539. ; 34:5, s. 460-467
-
Tidskriftsartikel (refereegranskat)abstract
- Bangladesh became the first country in South Asia to ban the use of lead in gasoline in 1999. In 2003, two-stroke engine auto rickshaws were banned in the city centre of Dhaka, the capital of Bangladesh and one of the Asian mega-cities, in an attempt to improve the air quality. In July and August 2003, fine aerosol particles (PM2.5) were collected in Dhaka and in Rangpur in the northern part of the country. The aim was to study the effect of the action and to characterize PM2.5 particles in urban and rural areas of Bangladesh. Sampling was done with a cyclone of Dewell-Higgins type equipped with Teflon filters with a pore size of 3 mu m. Day- and night-time filters were collected in an attempt to understand the possible difference in air pollution between the two periods. An energy-dispersive x-ray fluorescence (EDXRF) spectrometer with three-axial geometry was utilized for the analysis of the elemental content of the particles. Large variations of concentrations for most elements in both Dhaka and in Rangpur were observed. Most of the elemental concentrations in Dhaka in daytime were higher than at night whereas the opposite was the case for Rangpur. The concentrations showed a significant influence of human activities and weather. Considerable concentrations of Pb were found despite the official ban of leaded gasoline. Motor transport, especially the two-stroke engine taxis and elements remobilized by burning, were the major sources identified. This is the first report on elemental concentrations in PM2.5 particles in both Dhaka and Rangpur. Copyright (c) 2005 John Wiley & Sons, Ltd.
|
|
19. |
- Boman, Johan, 1955, et al.
(författare)
-
Elemental content of aerosol particles in an underground tram station
- 2009
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539.
-
Tidskriftsartikel (refereegranskat)abstract
- Particulate matter is an important air pollutant, especially in closed environments like a tunnel. The aim of this study was to determine the mass, black carbon, and elemental concentrations of particulate matter of two size fractions at an underground tram station in Hammarkullen, Gothenburg, Sweden. Samples were collected during June 2007 using a dichotomous virtual impactor separating the sampled aerosol particles into coarse (PM(2.5-10)) and fine (PM2.5) fractions. To minimize the possible influence of waiting passengers, the platform for trams going towards the suburb Angered was chosen. The elemental analysis of the samples, collected on Teflon filters, was carried out using energy dispersive x-ray fluorescence (EDXRF) spectrometry, resulting in concentrations of 14 elements in most of the samples. Principal component analysis (PCA) was applied to identify possible sources for the elements in the particles. Owing to the tunnel environment, the elemental difference between the fine and coarse particle fractions was not as large as that in similar particles collected under normal outdoor ambient conditions. Likewise, the influence of the local weather situation was not significant. Particle content from the tram traffic was identified by PCA, with Fe being the major element in both coarse and fine particles. The particle mass concentration was higher in the tunnel compared to the ambient concentration at the monitoring station Femman in downtown Gothenburg. In some days, the mass concentration exceeded the Swedish daily ambient air quality standard of 50 µg m-3, but it was lower than the limits in the environmental work act, 5 mg m-3.
|
|
20. |
- Boman, Johan, 1955, et al.
(författare)
-
Elemental content of PM2.5 aerosol particles collected in Göteborg during the Göte-2005 campaign in February 2005
- 2008
-
Ingår i: Atmos. Chem. Phys. Discuss. ; 8:2, s. 7703-7724
-
Tidskriftsartikel (refereegranskat)abstract
- Göte–2005 was a measurement campaign in the city of Göteborg with the aim of studying the influence of the winter thermal inversions on urban air pollution. Elemental speciation of PM2.5 aerosol particles, collected on Teflon filters at three urban sites and one rural site in the Göteborg region, was a major part of the study. Trace element analysis was done by Energy Dispersive X-Ray Fluorescence (EDXRF) spectrometry and the concentrations of S, Cl, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, Br and Pb were determined. The elemental content of the particles in combination with information of local wind speed and direction and also backward trajectories were used to estimate the source areas of the pollutants. We can conclude that S, V, Ni, Br, and Pb have their main sources outside the Göteborg area, since we cannot see elevated concentrations of these elements during an inversion episode. Sea traffic and harbour activities were also identified, primarily by the S and V content of the particles. This study proves that the elemental analysis by EDXRF presents valuable information for tracing the origin of air masses arriving at a measurement site.
|
|
21. |
- Boman, Johan, 1955, et al.
(författare)
-
Elemental content of PM2.5 aerosol particles collected in Göteborg during the Göte-2005 campaign in February 2005
- 2009
-
Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 9, s. 2597-2606
-
Tidskriftsartikel (refereegranskat)abstract
- The Göte-2005 measurement campaign aimed at studying the influence of the winter thermal inversions on urban air pollution. Elemental speciation of PM2.5 aerosol particles, collected on Teflon filters at three urban sites and one rural site in the Göteborg region, was a major part of the study. Trace element analysis was done by Energy Dispersive X-Ray Fluorescence (EDXRF) spectrometry and the concentrations of S, Cl, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, Br and Pb were determined. The elemental content of the particles, local wind speed and direction, and backward trajectories were used to investigate possible sources for the pollutants. We concluded that S, V, Ni, Br, and Pb had their main sources outside the central Göteborg area, since elevated concentrations of these elements were not observed during an inversion episode. Sea traffic and harbour activities were identified, primarily by the S and V content of the particles. This study showed that the elemental analysis by EDXRF presents valuable information for tracing the origin of air masses arriving at a measurement site.
|
|
22. |
- Boman, Johan, 1955, et al.
(författare)
-
Mass, black carbon and elemental composition of PM2.5 at an industrial site in Kingston, Jamaica
- 2015
-
Ingår i: Nuclear Instruments and Methods in Physics Reseach B. - : Elsevier BV. - 0168-583X. ; 363, s. 131-134
-
Tidskriftsartikel (refereegranskat)abstract
- An estimated three million premature deaths yearly can be attributed to ambient particulate pollution, a majority of them in low and middle income countries. The rapid increase in the vehicle fleet in urban areas the Caribbean countries have experienced contributes to the bad urban air quality. In this study aerosol particles with an aerodynamic diameter smaller than, or equal to, 2.5 µm (PM2.5) were collected over 24 hours at a site along Spanish Town Road, one of the main commuter roads in Kingston, Jamaica. The study was aimed at determining the mass, black carbon and elemental composition of PM2.5 in Kingston. Although lead in the gasoline was phased out in the year 2000, up to 5000 ppm of sulfur is still allowed in the diesel, leading to an extensive secondary particle formation. PM2.5 samples were collected using a Mini-vol sampler between 12 December 2013 and 21 March 2014 and analyzed for trace elements using the Particle-Induced X-ray Emission (PIXE) facility at Lund University, Sweden. Concentrations of Si, S, Cl, K, Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, Br and Pb were determined. Elemental concentrations showed a high temporal variation and the average PM2.5 concentration (44 µg m-3) is higher than the air quality standards that apply in the European Union (25 µg m-3) and in the USA (12 µg m-3). From this we can conclude that the air quality in the area is severely influenced by PM2.5 pollution and that there is a need to develop plans for improving the air quality in Kingston city.
|
|
23. |
- Boman, Johan, 1955, et al.
(författare)
-
On the elemental composition of PM2.5 in central Cairo, Egypt
- 2013
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 1097-4539 .- 0049-8246. ; 42:4, s. 276-283
-
Tidskriftsartikel (refereegranskat)abstract
- Aerosol particles are among the criteria pollutants identified by many countries because of their effects on human health and the environment. Information about the elemental composition of the aerosol particles is useful for source apportionment and determining the possible negative effects of the particulate air pollution. In this study, fine aerosol particles (PM2.5) were collected over 24 h once a week at roof level at the National Research Center in the center of Cairo, Egypt, between September 2010 and May 2011 using a cyclonic sampler. The site is representative of urban residential areas in the center of this megacity. Elemental determination was performed using an energy dispersive X-ray fluorescence spectrometer with a Mo secondary target, and the measured concentrations were evaluated using the quantitative X-ray analysis system/AXIL software package. The concentrations of 16 elements were determined in the collected aerosol samples, although some were generally not present at levels above the method’s limit of detection. The concentrations of many of the elements exceeded those in other urban environments. The concentration of Pb was 95 +- 200 ng/m3 , well below the Egyptian legal limit of 500 ng/m3 . This represents a significant decrease since 1997, when concentrations above 3 mg/m3 were measured. The decrease is due to the banning of Pb in vehicle fuel in 1997 and the movement of Pb smelters from the central part of Cairo in 2002. Analysis of the elemental concentrations revealed seasonal variation in their levels and possible sources of the emissions, and enabled us to estimate their effects on human health.
|
|
24. |
- Boman, Johan, 1955, et al.
(författare)
-
PM2.5 at a semi-rural site near Beijing, China
- 2023
-
Ingår i: X-Ray Spectrometry. - 0049-8246. ; 52:6, s. 447-56
-
Tidskriftsartikel (refereegranskat)abstract
- Breathing clean air is a human right still not accessible to everyone. In most of the world, the air is polluted, which affects both the environment and human health. To investigate the air pollution situation in a semi-rural part of northern China, particles with a diameter below 2.5 & mu;m (PM2.5) were collected in Changping, 40 km northwest of Beijing in May and June 2016. The particles were analyzed for mass, trace elements, and black carbon (BC). The mean PM2.5 mass was 49 & mu;g/m(3), ranging from 3.1 to 266 & mu;g/m(3). S, Cl, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, As, and Pb were determined by Energy Dispersive X-Ray Fluorescence (EDXRF). They constituted 4% of the PM2.5 mass, with BC adding another 3%. Enrichment factor evaluation identified S, Ni, Cu, Zn, As, and Pb as the main anthropogenic contributors to environmental impact. A pollution load index (PLI) of 0.03 showed that the site could not be considered as polluted by the trace elements in PM2.5. Positive matrix factorization (PMF) was used for source apportionment of the PM2.5 content. The PMF analysis reveals that a mixture of mineral dust, fossil fuel combustion, industries, and salts were the main sources of air pollution. The non-carcinogenic and carcinogenic health risks were assessed, and both show a small health risk in the short study period. Following the development of PM2.5 concentrations over time in this part of China shows a decreasing trend of PM2.5 pollution, which is promising for the future.
|
|
25. |
- Boman, Johan, 1955
(författare)
-
Preface to the Special Issue of the 2016 European Conference on X-ray Spectrometry
- 2017
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539. ; 46:2, s. 80-81
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The 17th European X-Ray Spectrometry Conference (EXRS2016) was held in Gothenburg on the Swedish west coast, between 19th and 24th June 2016. The conference was hosted by University of Gothenburg in cooperation with the International Atomic Energy Agency (IAEA) with the support of European X-Ray Spectrometry Association (EXSA). This editoral text is an introduction to the special issue.
|
|
26. |
- Boman, Johan, 1955, et al.
(författare)
-
The Linnaeus-Palme Exchange program — A program evaluation report for the period 2006-2012
- 2013
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The report is an evaluation of five years of Linnaeus-Palme exchange programme between the chemistry departments at University of Gothenburg, Sweden and University of the West Indies, Jamaica. The exchange programme gives students and teachers at the two universities the possibility to study and teach at the partner university to better understand the international implications of studies and teaching but also from a more general standpoint. The outcomes were evaluated by participants’ reports, questionnaires and discussions with the participants and heads of department. The result of the evaluation is a positive response from all partners; students, teachers, coordinators, departmental heads. They report a high degree of satisfaction, a better understanding of cultural differences and the students rate a better self-confidence high.
|
|
27. |
- Boman, Johan, 1955, et al.
(författare)
-
Trace elements in PM2.5 in Gothenburg, Sweden
- 2010
-
Ingår i: Spectrochimica Acta - Part B: Atomic Spectroscopy. - : Elsevier BV. - 0584-8547. ; 65:6, s. 478-482
-
Tidskriftsartikel (refereegranskat)abstract
- Ambient aerosol particles smaller than 2.5 µm (PM2.5) are getting more and more attention worldwide. While legal focus is mainly on sample mass, the composition of the particles is an important research field gaining increased interest. The interest is not only connected to possible health effects of the elemental content of the particles, but the elemental determination can also add valuable information for source apportionment. Samples were collected during 20 days in November 2007 at the campus of the Chemistry Department, University of Gothenburg, Gothenburg, Sweden. The particles were collected using a cyclone that separates the PM2.5 particles from the air stream and impacts them on polycarbonate filters. Filters were changed at early afternoon. The samples were analyzed for particulate mass, black carbon (BC) and the elements S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, As, Br, Cd and Pb. Several of the elements were above detection limit in only a few of the samples. Total reflection X-ray fluorescence (TXRF) spectrometer based on the Wobi TXRF module supplied by the International Atom Energy Agency (IAEA) has been used for the determination of most trace elements in the samples. A Graphite Furnace Atomic Absorption Spectrometer (GF-AAS) was used for complementary trace element analysis and a reflectometer was used to analyze black carbon. Before elemental analysis the filters were digested using a microwave digestion system with temperature and pressure control. The results showed a large variation in sample mass, BC and analyzed elemental concentrations. The variation of the different constituents did not show the same pattern. This added to the picture of different sources for different pollutants. The highest S concentration was noted on a day when the air masses were determined to come from the southeast, i.e. Poland and some other Eastern European countries. From the results it can be concluded that more work is needed on the TXRF spectrometer to optimize it for determination of the EU legally regulated elements As, Ni, Pb and Cd. Despite this the study shows that there is no problem in meeting the AAQS limits for Cd and Pb in Gothenburg.
|
|
28. |
- Boman, Johan, 1955, et al.
(författare)
-
XRS reviewer award editorial 2022
- 2022
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539. ; 51:5, s. 420-1
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
29. |
- Bølling, Anette Kocbach, et al.
(författare)
-
Wood smoke particles from different combustion phases induce similar pro-inflammatory effects in a co-culture of monocyte and pneumocyte cell lines.
- 2012
-
Ingår i: Particle and fibre toxicology. - : Springer Science and Business Media LLC. - 1743-8977. ; 9:1
-
Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT: BACKGROUND: Exposure to particulate matter (PM) has been linked to several adverse cardiopulmonary effects, probably via biological mechanisms involving inflammation. The pro-inflammatory potential of PM depends on the particles' physical and chemical characteristics, which again depend on the emitting source. Wood combustion is a major source of ambient air pollution in northern countries during the winter season. The overall aim of this study was therefore to investigate the cellular responses to wood smoke particles (WSPs) collected from different phases of the combustion cycle, and from combustion at different temperatures. RESULTS: WSPs from different phases of the combustion cycle induced very similar effects on pro-inflammatory mediator release, cytotoxicity and cell number, whereas WSPs from medium-temperature combustion were more cytotoxic than WSPs from high-temperature incomplete combustion. Furthermore, comparisons of effects induced by native WSPs with the corresponding organic extracts and washed particles revealed that the organic fraction was the most important determinant for the WSP-induced effects. However, the responses induced by the organic fraction could generally not be linked to the content of the measured polycyclic aromatic hydrocarbons (PAHs), suggesting that also other organic compounds were involved. CONCLUSION: The toxicity of WSPs seems to a large extent to be determined by stove type and combustion conditions, rather than the phase of the combustion cycle. Notably, this toxicity seems to strongly depend on the organic fraction, and it is probably associated with organic components other than the commonly measured unsubstituted PAHs.
|
|
30. |
- Chen, Jing, et al.
(författare)
-
Impact of relative humidity and water soluble constituents of PM2.5 on visibility impairment in Beijing, China
- 2014
-
Ingår i: Aerosol and Air Quality Research. - : Taiwan Association for Aerosol Research. - 1680-8584 .- 2071-1409. ; 14:1, s. 260-268
-
Tidskriftsartikel (refereegranskat)abstract
- Beijing has been experiencing severe particulate pollution accompanying the fast growing population and economy. This study investigated the impact of PM2.5 and its water soluble organic and inorganic constituents on visual impairment in Beijing under different meteorological conditions. According to the analysis of PM2.5 samples collected in Spring 2012, water soluble species took up 38.1% of PM2.5 mass, among which NO3– was the most abundant constituent, followed by SO42–, NH4+ and water soluble organic matter. The correlation analysis between visibility and aerosol loadings as well as meteorological parameters revealed the dominant impact of meteorological conditions, relative humidity in particular, on visibility impairment over the mass concentration of PM2.5. Compared to the total aerosol loading of PM2.5, visibility was better correlated with the total mass of water soluble constituents (WSC). The visual range in Beijing was the most sensitive to both WSC and PM2.5 in the RH range of 30–70%. Severe visual impairment was observed for RH ≥ 70% with the least sensitivity to WSC and PM2.5. The effects of synoptic scale circulation on meteorological variables that affect air quality were also examined with the movement of a cold front as a case study. The findings have direct implications to region-wide policy-making and control strategies.
|
|
31. |
- Cincera, J, et al.
(författare)
-
Designing a sustainability-driven entrepreneurship curriculum as a social learning process: A case study from an international knowledge alliance project
- 2018
-
Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 172, s. 4357-4366
-
Tidskriftsartikel (refereegranskat)abstract
- Integrating Education for Sustainable Development (ESD) in higher education curricula requires innovative ideas and approaches how to combine educational, sustainability and disciplinary knowledge, skills, experiences, and motivations. Curriculum developers are challenged to be open to new concepts in their discipline regarding what should be taught and how it can be taught to facilitate learning processes to prepare students for shaping a sustainable future. The European project ‘Competencies for A Sustainable socio-Economic development’ (CASE) follows a participatory, inter- and transdisciplinary approach to design a Master’s program on sustainability-driven entrepreneurship. This study presents an analysis of the social learning process that has taken place in the interdisciplinary, intercultural CASE team during the participatory development process of the new Master’s program. The methodological design of the study is based on qualitative, participative evaluation research. The process of learning is discussed based on how the group reflected on and developed their “action theories” on how to design a supportive learning environment in which a Master’s program with innovative scopes and goals can be created. The findings highlight the importance of sharing and processing the experiences, mental models and interpretations concerning concepts, ideas, perspectives and new input within the group. This seems crucial for developing the capacity of the group to bring together diverse knowledge and perspectives for innovative, feasible solutions and ideas as well as to cooperate and collaborate effectively as a team. The implications of a culture of dialogue, participation and learning in diverse teams as important principles for developing innovative ESD-based curricula in different disciplines are discussed. It is emphasized that not only students, but also curriculum developers have to acquire the corresponding ESD-related competencies.
|
|
32. |
- Gaita, Samuel Mwaniki, 1976, et al.
(författare)
-
Characterization of Size-Fractionated Particulate Matter and Deposition Fractions in Human Respiratory System in a Typical African City: Nairobi, Kenya
- 2016
-
Ingår i: Aerosol and Air Quality Research. - : Taiwan Association for Aerosol Research. - 2071-1409 .- 1680-8584. ; 16:10, s. 2378-2385
-
Tidskriftsartikel (refereegranskat)abstract
- Information from elemental and mass composition of size-fractionated airborne particle matter (PM) provides insightfulknowledge about their impact on human health, meteorology and climate. To attain insight into the nature of sizefractionatedPM from a typical African city, samples were collected from an urban background site in Nairobi, Kenya,during the months of August and September in 2007. PM samples ranging in size from 0.06 to 16 µm aerodynamicdiameter were collected on pre-weighed polycarbonate filters with 0.4 µm pore size using a nine-stage cascade impactor.Particles less than 0.06 µm were collected on a backup filter. A total of 170 samples were collected and analysed for traceelements using the Proton Induced X-Ray Emission (PIXE) technique. The analysis showed that Si, Fe and S dominated inall size ranges and displayed unimodal mass-size distribution whereas K, Cu, Zn and Pb, depicted bimodal mass-sizedistribution highlighting the multiplicity of their sources. To estimate human exposure to PM, deposition fractions of boththe coarse and fine PM in the human respiratory system were calculated. The deposited concentration was found to behighest in the head airways region compared to the tracheobronchial and pulmonary regions.
|
|
33. |
- Gaita, Samuel Mwaniki, 1976, et al.
(författare)
-
Source apportionment and seasonal variation of PM2.5 in a Sub-Sahara African city : Nairobi, Kenya
- 2014
-
Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 14:18, s. 9977-9991
-
Tidskriftsartikel (refereegranskat)abstract
- Sources of airborne particulate matter and their seasonal variation in urban areas in Sub-Saharan Africa are poorly understood due to lack of long-term measurement data. In view of this, filter samples of airborne particulate matter (particle diameter ≤2.5 μm, PM2.5) were collected between May 2008 and April 2010 at two sites (urban background site and suburban site) within the Nairobi metropolitan area. A total of 780 samples were collected and analyzed for particulate mass, black carbon (BC) and 13 trace elements.The average PM2.5 concentration at the urban background site was 21±9.5 μg m−3, whereas the concentration at the suburban site was 13±7.3 μg m−3. The daily PM2.5 concentrations exceeded 25 μg m−3 (the World Health Organization 24 h guideline value) on 29% of the days at the urban background site and 7% of the days at the suburban site. At both sites, BC, Fe, S and Cl accounted for approximately 80% of all detected elements. Positive matrix factorization analysis identified five source factors that contribute to PM2.5 in Nairobi, namely traffic, mineral dust, industry, combustion and a mixed factor (composed of biomass burning, secondary aerosol and aged sea salt).Mineral dust and traffic factors were related to approximately 74% of PM2.5. The identified source factors exhibited seasonal variation, apart from the traffic factor, which was prominently consistent throughout the sampling period. Weekly variations were observed in all factors, with weekdays having higher concentrations than weekends. The results provide information that can be exploited for policy formulation and mitigation strategies to control air pollution in Sub-Saharan African cities.
|
|
34. |
- Gatari, Michael J, et al.
(författare)
-
Assessment of inorganic content of PM(2.5) particles sampled in a rural area north-east of Hanoi, Vietnam.
- 2006
-
Ingår i: The Science of the total environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 368:2-3, s. 675-85
-
Tidskriftsartikel (refereegranskat)abstract
- Atmospheric aerosols from seven rural sites in northern Vietnam, east of Hanoi, were sampled and analyzed. The aim of the study was to evaluate trace elemental and black carbon (BC) concentrations in fine particles (PM(2.5)) and to investigate the influence of the Pha Lai power plant and other pollution sources on regional air quality. Seven measurement stations were set up at selected rural sites and a campaign consisting of 12 two-day measurement periods was conducted from the end of May until the end of October 2000. At each location a pair of samplers was installed consisting of a cyclone loaded with Teflon filters and a modified Millipore air monitoring cartridge loaded with glass fibre filters. The obtained samples were analyzed for trace elements by Energy Dispersive X-ray Fluorescence (EDXRF), while a black smoke detector was used for BC analysis. Seventeen trace elements were analyzed; Br, Ca, Cl, Cr, Cu, Fe, K, Mn, Ni, Pb, Rb, S, Se, Sr, Ti, V and Zn and their concentrations evaluated. The results showed that BC, Ca, Cl, Fe, K and S dominated in the sampled atmospheric aerosols. The measured concentrations of the potentially hazardous trace elements Cr, Mn, Ni and Pb were all below the limits defined by Vietnamese standards of ambient air quality. Statistical evaluations indicated that coal and heavy fuel oil combustion were major sources of atmospheric pollutants in the area and that biomass burning and road transport had a marked influence on regional air quality. It was concluded that the Pha Lai power plant was the major source of coal combustion emissions. Trace element emissions originating from river transportation were suggested as another major source of atmospheric pollutants. The results indicate that the elemental concentrations in PM(2.5) are strongly influenced by seasonal variations. Further measurements are required to identify the impact of long-range transported continental air masses on the air quality of the investigated rural area.
|
|
35. |
- Gatari, M. J., et al.
(författare)
-
Characterization of aerosol particles at an industrial background site in Nairobi, Kenya
- 2009
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539. ; 38:1, s. 37-44
-
Tidskriftsartikel (refereegranskat)abstract
- Air pollutants from industrial and urban sources contain harmful elements and chemical compounds. This work presents a study on background industrial and urban aerosol particles in the city of Nairobi. Its main focus was the understanding of elemental, black carbon (BC) and particulate mass (PM) concentrations in the perspective of identifying their sources. Aerosol particles were collected on Teflon filters in two size fractions, a fine fraction of particles having an aerodynamic diameter (da) < 2.5 µm and a coarse fraction with particles between 2.5 and 10 µm. A photometer and an energy dispersive x-ray fluorescence spectrometer were used to analyse BC and trace elements (Si, S, Cl, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr and Pb), respectively. The sampled mass of the particulate matter was determined gravimetrically. The measured concentrations of the analysable species were dominated by BC, K and S in the fine fraction and Si, Ca and Fe in the coarse fraction. Principal component analysis and correlation evaluation of the fine fraction concentrations implicated industrial, vehicular and biomass-burning emissions as the main sources of the measured elements. The average Pb concentration of 105 ng m-3 in the PM10 samples at the background industrial site was approximately 20% of the air quality guideline (AQG) recommended by World Health Organisation (WHO). Most of the measured elements exhibited higher concentrations than those measured in Francistown in Botswana, Dar es Salaam in Tanzania and Edinburgh in United Kingdom but less than those measured in Barcelona in Spain and from previous studies in Nairobi.
|
|
36. |
- Gatari, Michael J, et al.
(författare)
-
Elemental composition of tropospheric aerosols in Hanoi, Vietnam and Nairobi, Kenya.
- 2005
-
Ingår i: The Science of the total environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 341:1-3, s. 241-9
-
Tidskriftsartikel (refereegranskat)abstract
- Air pollution problems in major cities within the developing countries need to be studied. There are scanty measurements from the developing countries on airborne particles despite their adverse implications to human health, visibility and climate. One of the major sources of anthropogenic air pollution is energy production. Energy demand is bound to increase as population increases, especially in major cities of the world. Fine particles, particles with aerodynamic diameter < or = 2.5 microm, are mainly anthropogenic and these particles were collected in the capital cities of Vietnam and Kenya. A cyclone airborne particle collector was used to sample in Hanoi during the months of May to October 2000 and a dichotomous virtual impactor in Nairobi in February 2000. The samples were analysed for elemental content by an energy dispersive X-ray fluorescence (EDXRF) spectrometer. S, Cl, K and Fe exceeded atmospheric concentrations of 100 ng m(-3) at both cities. Atmospheric elemental concentrations in both Hanoi and Nairobi were orders of magnitude higher than their respective rural towns. Traffic, biomass and waste burning emissions were implicated as the main sources of air pollution in Nairobi, while coal combustion and road transport were the major sources in Hanoi. Regional air pollution had a major impact over Hanoi, whereas an influence of that kind was not identified in Nairobi. Pb and other toxic elements had concentration levels below WHO guideline, however, the two cities are threatened by future high levels of air pollution due to the high rate of population growth. Long-term measurements are required in both areas to evaluate if the alarming situation is deteriorating.
|
|
37. |
- Gatari, Michael J, et al.
(författare)
-
Inorganic and black carbon aerosol concentrations at a high altitude on Mt Kenya
- 2009
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539. ; 38:1, s. 26-36
-
Tidskriftsartikel (refereegranskat)abstract
- Aerosol samples were collected at an altitude of 3678 m on Mt Kenya in August 2001. A virtual impactor was used to collect particles in fine (aerodynamic diameter, da < 2.5 µm) and coarse (2.5 µm < da < 10 µm) size fractions. The samples were analyzed for particulate mass (PM), black carbon (BC) and 15 elements. The PM concentrations varied in the ranges 3.3 ± 1.1-7.8 ± 2.5 µg m-3 (in fine fraction) and 3.7 ± 1.2-9.6 ± 3.0 µg m-3 (in coarse fraction). The fine fraction was dominated by high concentrations of BC, S and K due to particles formed during biomass burning and sulfate particles from secondary processes in the atmosphere. The coarse fraction was dominated by high concentrations of Si, S, Cl, K, Ca and Fe indicative of the presence of soil dust particles. This was further verified by enrichment factors (EFs) calculated using the elemental content of the average crustal rock. Chemical mass balance (CMB) calculations indicated that the PM was largely attributable to biomass burning, mineral dust and sulfate, while contributions from anthropogenic sources were small. Source apportionment of elemental concentrations compared well with that of an earlier study on the southwestern slope of Mt Kenya, while PM and sulfate concentrations were comparable with those observed at high-altitude sites in North America and Europe. The observed concentrations were 5-50 times lower than those of urban Kenya.
|
|
38. |
- Gatari, Michael J, et al.
(författare)
-
Trace element categorization of pollution sources in the equator town of Nanyuki, Kenya
- 2005
-
Ingår i: X-Ray Spectrometry. ; 34:2, s. 118-123
-
Tidskriftsartikel (refereegranskat)abstract
- An air pollution campaign was carried out in the town of Nanyuki at four different sites during July and August 1999. Nanyuki is situated on the equator on the northwestern slope of Mount Kenya at about 1930 m above sea level. The intention of the project was to characterize aerosol elemental compositions in two size fractions, associated with specific natural and anthropogenic activities. A dichotomous impactor was used for sampling and an energy-dispersive x-ray fluorescence spectrometer was used for the analysis. Fourteen elements (Si, S, K, Ca, Ti, Mn, Fe, Cu, Zn, Ga, Br, Rb, Sr and Pb) were analysed in all the samples. The concentration of Pb was highest at a site in the vicinity of open-air vehicle garages. The four sites recorded high concentrations of fine S, Cl and K. Fine Zn and Br were also measured at all the sites. In the coarse size range, the concentrations of soil-derived elements (Si, K, Ca and Fe) were dominant. The high concentration of coarse Cl was considered to be due to the contribution of sea salt and that of S to be a contribution of gas to particle conversion of SO2. The two elements S and Cl signified the influence of long-distance transported aerosols. The comparatively high concentrations of fine Pb and Br signified the high rate of vehicle repairs, which is a major activity close to one of the sites. Generally, soil dust-derived particles and those from biomass burning dominated the town aerosols.
|
|
39. |
- Hallquist, Mattias, 1969, et al.
(författare)
-
Analysis of organic substances and trace elements in aerosol samples using Fourier transform infra-red and total reflection X-ray fluorescence methods, initial experiments
- 2004
-
Ingår i: Spectrochimica Acta Part B-Atomic Spectroscopy. - : Elsevier BV. - 0584-8547. ; 59:8, s. 1193-1197
-
Tidskriftsartikel (refereegranskat)abstract
- The ann of this study was to find a way to analyze trace elements as well as organic functional groups in the same aerosol sample. Size segregated aerosol particles were produced under laboratory conditions. The particles contained known amounts of inorganic and organic compounds and were analyzed using total reflection X-ray fluorescence (TXRF) and Fourier transform infra-red (FTIR) spectroscopy for their inorganic and organic content, respectively. A linear relation was obtained between the inorganic content from the TXRF analysis and specific organic functional groups evaluated by FTIR, although a transfer of the sample from quartz plates to zincselenide plates was necessary. The linear relation can be used for quantification of organic functional groups of other aerosol samples. Further improvements and possible applications of the combined techniques are discussed. (C) 2004 Elsevier B.V. All rights reserved.
|
|
40. |
|
|
41. |
- Howlett-Downing, C., et al.
(författare)
-
Case-crossover study for the association between increased hospital admissions for respiratory diseases and the increase in atmospheric PM2.5 and PM2.5-bound trace elements in Pretoria, South Africa
- 2023
-
Ingår i: International Journal of Environmental Health Research. - 0960-3123. ; 34:3
-
Tidskriftsartikel (refereegranskat)abstract
- Outdoor PM2.5 was sampled in Pretoria, 18 April 2017 to 28 February 2020. A case-crossover epidemiology study was associated for increased PM2.5 and trace elements with increased hospital admissions for respiratory disorders (J00-J99). The results included a significant increase in hospital admissions, with total PM2.5 of 2.7% (95% CI: 0.6, 4.9) per 10 & mu;g & BULL;m(-3) increase. For the trace elements, Ca of 4.0% (95% CI: 1.4%-6.8%), Cl of 0.7% (95% CI: 0.0%-1.4%), Fe of 3.3% (95% CI: 0.5%-6.1%), K of 1.8% (95% CI: 0.2-3.5) and Si of 1.3% (95% CI: 0.1%-2.5%). When controlling for PM2.5, only Ca of 3.2% (95% CI: 0.3, 6.1) and within the 0-14 age group by 5.2% (95% CI: 1.5, 9.1). Controlling for a co-pollutant that is highly correlated with PM2.5 does reduce overestimation, but further studies should include deposition rates and parallel sampling analysis.
|
|
42. |
- Howlett-Downing, C., et al.
(författare)
-
Health risk assessment of PM2.5 and PM2.5-bound trace elements in Pretoria, South Africa
- 2023
-
Ingår i: Journal of Environmental Science and Health Part a-Toxic/Hazardous Substances & Environmental Engineering. - : Informa UK Limited. - 1093-4529 .- 1532-4117. ; 58:4, s. 342-358
-
Tidskriftsartikel (refereegranskat)abstract
- Exposure to outdoor air pollutants poses a risk for both non-carcinogenic and carcinogenic respiratory disease outcomes. A standardized health risk assessment (US EPA) utilizes air quality data, body mass and breathing rates to determine potential risk. This health risk assessment study assesses the hazard quotient (HQ) for total PM2.5 and trace elemental constituents (Br, Cl, K, Ni, S, Si, Ti and U) exposure in Pretoria, South Africa. The World Health Organization (WHO) air quality guideline (5 mu g m(-3)) and the yearly South African National Ambient Air Quality Standard (NAAQS) (20 mu g m(-3)) were the references dosages for total PM2.5. A total of 350 days was sampled in Pretoria, South Africa. The mean total PM2.5 concentration during the 34-month study period was 23.2 mu g m(-3) (0.7-139 mu g m(-3)). The HQ for total PM2.5 was 1.17, 3.47 and 3.78 for adults, children and infants. Non-carcinogenic risks for trace elements K, Cl, S and Si were above 1 for adults. Seasonally, Si was the highest during autumn for adults (1.9) and during spring for S (5.5). The HQ values for K and Cl were highest during winter. The exposure to Ni posed a risk for cancer throughout the year and for As during winters.
|
|
43. |
- Howlett-Downing, Chantelle, et al.
(författare)
-
PM2.5 Chemical Composition and Geographical Origin of Air Masses in Pretoria, South Africa
- 2022
-
Ingår i: Water, Air, and Soil Pollution. - : Springer Science and Business Media LLC. - 0049-6979 .- 1573-2932. ; 233
-
Tidskriftsartikel (refereegranskat)abstract
- In Africa, there is a paucity of studies that reported on PM2.5, soot, BC, UV-PM (organic carbon) and trace element levels in rural and urban regions. PM2.5 samples were collected over 24 h and every third day during 19 April 2018 and 28 February 2020. The mean PM2.5 level was 24.1 μg.m−3 (range: 2.9–139 μg.m−3). PM2.5 levels exceeded the yearly World Health Organization (WHO) air quality guideline (5 μg.m−3). The daily WHO guideline (15 μg.m−3) was exceeded on 151 of the 228 days. The mean soot, black carbon and organic carbon levels were 1.43 m−1 × 10−5, 2.7 μg.m−3 and 2.1 μg.m−3, respectively. Twelve PM2.5-bound trace elements (Br, Ca, Cl, Cu, Fe, K, Ni, S, Si, Ti, U and Zn) were analysed. The geographical origin of air masses that passed the study site was estimated using the Hybrid Single-Particle Lagrangian Integrated Trajectory software. Four air masses were identified. The observed PM2.5, soot, BC, UV-PM and trace element levels at this urban background study site could potentially pose a significant risk to human health.
|
|
44. |
- Howlett-Downing, Chantelle, et al.
(författare)
-
Source Apportionment of PM2.5 and PM2.5-Bound Trace Elements in Pretoria, South Africa
- 2023
-
Ingår i: ENVIRONMENTAL FORENSICS. - 1527-5922 .- 1527-5930.
-
Tidskriftsartikel (refereegranskat)abstract
- Outdoor PM2.5 samples were collected for 34 months in Pretoria, South Africa from 18 April 2017 to 28 February 2020. The average total PM2.5 concentration was 23.2 +/- 17.3 mu g.m(3) (0.69-139 mu g.m(-3)), with the highest mean recorded during winter and the lowest during summer (p < 0.05). The sources were determined by means of cross referencing the US EPA PMF 5.0 program and the NOAA HYsplit model. The sources of the total PM2.5 were mining (33%), resuspended dust (24%), industry (15%), general exhaust (12%), vehicular emissions (12%) and biomass burning (4%). Sources of air pollutants are both ubiquitous and seasonal.Highlights center dot In central Pretoria, the largest contributing sources of PM2.5 are resuspended dust matrix and mining from surrounding areas;center dot A winter analysis was run where As, Se and Pb was included in the dataset, confirming biomass burning sources which were typically higher during the winter season; and center dot Air quality management policies should address both ubiquitous and seasonal sources.
|
|
45. |
- Kilbo Edlund, Karl, et al.
(författare)
-
Health Risk Assessment of PM2.5 and PM2.5-Bound Trace Elements in Thohoyandou, South Africa
- 2021
-
Ingår i: International Journal of Environmental Research and Public Health. - : MDPI AG. - 1660-4601. ; 18:3
-
Tidskriftsartikel (refereegranskat)abstract
- We assessed the health risks of fine particulate matter (PM2.5) ambient air pollution and its trace elemental components in a rural South African community. Air pollution is the largest environmental cause of disease and disproportionately affects low- and middle-income countries. PM2.5 samples were previously collected, April 2017 to April 2018, and PM2.5 mass determined. The filters were analyzed for chemical composition. The United States Environmental Protection Agency's (US EPA) health risk assessment method was applied. Reference doses were calculated from the World Health Organization (WHO) guidelines, South African National Ambient Air Quality Standards (NAAQS), and US EPA reference concentrations. Despite relatively moderate levels of PM2.5 the health risks were substantial, especially for infants and children. The average annual PM2.5 concentration was 11 mu g/m(3), which is above WHO guidelines, but below South African NAAQS. Adults were exposed to health risks from PM2.5 during May to October, whereas infants and children were exposed to risk throughout the year. Particle-bound nickel posed both non-cancer and cancer risks. We conclude that PM2.5 poses health risks in Thohoyandou, despite levels being compliant with yearly South African NAAQS. The results indicate that air quality standards need to be tightened and PM2.5 levels lowered in South Africa.
|
|
46. |
- Kovacevik, Borka, 1972, et al.
(författare)
-
Elemental composition of fine particulate matter (PM2.5) in Skopje, FYR of Macedonia
- 2011
-
Ingår i: X-Ray Spectrometry. - : Wiley. - 0049-8246 .- 1097-4539. ; 40:4, s. 280-288
-
Tidskriftsartikel (refereegranskat)abstract
- Aerosol samples were collected at an urban background site in Skopje, Former Yugoslavic Republic of Macedonia, during four measurement campaigns from December 2006 to October 2007. An impactor was used to collect particulate matter (PM2.5) aerosol particles and the samples were analyzed for the concentrations of particulate mass, black carbon (BC), and 17 elements. The 12-h average PM2.5 concentrations varied in the range 10-140 mu g m(-3) with the highest concentrations measured during wintertime pollution episodes and during the summer period. Pair-wise correlations and crustal enrichment were studied and the data set was analyzed by factor analysis and positive matrix factorization. Major aerosol components were identified as mineral dust (main observed tracers Si, K, Ca, Ti, Fe, Sr, and Rb), combustion (BC, S, K, V, and Ni), traffic-related aerosol (Pb and Zn), and secondary sulfate combined with mineral dust. Combustion sources dominated during wintertime and were likely due to heavy oil combustion, biomass burning, and other industrial activities within the city area. Mineral dust was observed throughout the year, but the concentrations peaked during the unusually hot and dry summer of 2007. It is concluded that Skopje suffers from serious air pollution due to central and residential heating, the transport sector, and industrial activities within the city, and contributions from mineral dust increase the PM2.5 concentrations under dry periods. Topography and meteorological conditions aggravate the problems and make the air quality comparable with the conditions in other highly polluted cities in Southern Europe and worldwide.
|
|
47. |
- Lewerissa, Karina Bianca, et al.
(författare)
-
Study of trace elements and soot in aerosols from a coal-fired power plant in northern Vietnam.
- 2007
-
Ingår i: Environmental monitoring and assessment. - : Springer Science and Business Media LLC. - 0167-6369 .- 1573-2959. ; 130:1-3, s. 301-9
-
Tidskriftsartikel (refereegranskat)abstract
- Two measurement campaigns were conducted in two sampling sites, An Thinh and Duy Minh, in northern Vietnam during the months of November-December 2000 and November 2001-February 2002 in order to investigate the extend of the particulate air pollution from the Pha Lai coal fired power plant. Fine particle samples were analyzed by Energy Dispersive X-Ray Fluorescence spectrometry and soot samples were analyzed by reflectometer. The result showed that high concentration of soot and elements mostly coincided with the air masses originating from the power plant. Sea spray aerosol was found to be the major source of chlorine at both sites. Ratios of specific elements and principal component analysis (PCA) revealed that coal combustion was the main contributor to the air pollution at both sites. PCA also indicated that there were other sources responsible for the elements emission, probably the influence of long distance transport and Asian Brown Cloud.
|
|
48. |
- Lindén, Jenny, 1975, et al.
(författare)
-
Intra-urban air pollution in a rapidly growing Sahelian city
- 2012
-
Ingår i: Environmental International. - : Elsevier BV. - 0160-4120. ; 40, s. 51-62
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we analyze spatial and temporal variations of air pollution (PM1, PM2.5, PM10, CO, NOx, O3, Toluene and Benzene) and climate in areas of different development typology in Ouagadougou, Burkina Faso. Analyses are based on measurements from fixed sites and car traverse measurements during field studies in 2007 and 2010. Large spatial and temporal variations were found, showing a generally poor air quality situation, with extreme levels of PM10, commonly exceeding air quality guidelines of WHO. Pollution levels increase considerably with increased atmospheric stability. Important sources were transported dust and re-suspension of dust from unpaved roads, but also traffic emissions and biomass burning. The spatial variations are examined with focus on effects for variations in potential exposure depending on for example area of residence and daily activity pattern, showing that great differences are likely to exist. Ouagadougou, like most developing countries worldwide, currently experiences an extremely rapid population growth in combination with limited financial means. This is likely to create increasingly harmful air pollution situations for the rapidly growing populations of these areas, and shows an urgent need for increased understanding of the pollution situation as well as development of mitigation strategies.
|
|
49. |
- Lindén, Jenny, 1975, et al.
(författare)
-
Urban climate and air pollution in Ouagadougou, Burkina Faso
- 2012
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The report Urban Climate and Air pollution in Ouagadougou, Burkina Faso contains an overview of results from five field studies as well as suggestions for air pollution mitigation strategies suitable for Ouagadougou.
|
|
50. |
- Liu, Wanyu, et al.
(författare)
-
Chemical and Hygroscopic Characterization of Surface Salts in the Qaidam Basin: Implications for Climate Impacts on Planet Earth and Mars
- 2021
-
Ingår i: ACS Earth and Space Chemistry. - : American Chemical Society (ACS). - 2472-3452. ; 5:3, s. 651-662
-
Tidskriftsartikel (refereegranskat)abstract
- Salt particles play important roles in many atmospheric processes due to their high hygroscopicity. Saline lakes and playas are sources of salt particles, which are normally mixed with mineral dust that can be transported over long distances. In this study, salt samples collected from four saline lakes and surrounding playas in the Qaidam Basin are studied for their physicochemical properties, focusing on the chemical compositions and hygroscopicity. The salt samples include brines, lakebed salts, crust salts, and crystallized brines. Thermodynamic models are used to explain the precipitating and hygroscopic behaviors based on ionic compositions of dissolved saline solutions. Regarding the ionic compositions, the crystallized brines are similar to the complex mineral compositions of brines, while the natural solid salts, including lakebed salts and crust salts, show very distinct composition differences. The main difference between brines and natural solid salts is the presence of Mg2+ and SO42–, which are primarily found in brines but not in the solid phases. Moreover, all the crust salts are dominated by NaCl regardless of the chemical compositions of the nearby saline lakes. Positive matrix factorization is applied to the ionic concentrations, and the results show that solid salts and brines are governed by different factors. The pH of brines correlates with Mg2+ concentrations and is potentially influenced by ambient CO2 uptake. The hygroscopicity experimental results and thermodynamic model outcomes show that the water uptake of different salt types is controlled by different salt components, that is, crystallized brines are controlled by MgCl2 and natural salts are governed by NaCl and KCl. The characterizations of saline lake and playa salts improve the understandings of the roles that surface salts potentially play in the climate systems of both Planet Earth and Mars.
|
|