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Links between air pollution and COVID-19 in England
2021
Travaglio, Marco | Yu, Yizhou | Popovic, Rebeka | Selley, Liza | Leal, Nuno Santos | Martins, Luis Miguel
In December 2019, a novel disease, coronavirus disease 19 (COVID-19), emerged in Wuhan, People’s Republic of China. COVID-19 is caused by a novel coronavirus (SARS-CoV-2) presumed to have jumped species from another mammal to humans. This virus has caused a rapidly spreading global pandemic. To date, over 300,000 cases of COVID-19 have been reported in England and over 40,000 patients have died. While progress has been achieved in managing this disease, the factors in addition to age that affect the severity and mortality of COVID-19 have not been clearly identified. Recent studies of COVID-19 in several countries identified links between air pollution and death rates. Here, we explored potential links between major fossil fuel-related air pollutants and SARS-CoV-2 mortality in England. We compared current SARS-CoV-2 cases and deaths from public databases to both regional and subregional air pollution data monitored at multiple sites across England. After controlling for population density, age and median income, we show positive relationships between air pollutant concentrations, particularly nitrogen oxides, and COVID-19 mortality and infectivity. Using detailed UK Biobank data, we further show that PM₂.₅ was a major contributor to COVID-19 cases in England, as an increase of 1 m³ in the long-term average of PM₂.₅ was associated with a 12% increase in COVID-19 cases. The relationship between air pollution and COVID-19 withstands variations in the temporal scale of assessments (single-year vs 5-year average) and remains significant after adjusting for socioeconomic, demographic and health-related variables. We conclude that a small increase in air pollution leads to a large increase in the COVID-19 infectivity and mortality rate in England. This study provides a framework to guide both health and emissions policies in countries affected by this pandemic.
Afficher plus [+] Moins [-]Source apportionment of fine particulate matter organic carbon in Shenzhen, China by chemical mass balance and radiocarbon methods
2018
Al-Naiema, Ibrahim M. | Yoon, Subin | Wang, Yu-Qin | Zhang, Yuan-Xun | Sheesley, Rebecca J. | Stone, Elizabeth A.
Chemical mass balance (CMB) modeling and radiocarbon measurements were combined to evaluate the sources of carbonaceous fine particulate matter (PM2.5) in Shenzhen, China during and after the 2011 summer Universiade games when air pollution control measurements were implemented to achieve air quality targets. Ambient PM2.5 filter samples were collected daily at two sampling sites (Peking University Shenzhen campus and Longgang) over 24 consecutive days, covering the controlled and uncontrolled periods. During the controlled period, the average PM2.5 concentration was less than half of what it was after the controls were lifted. Organic carbon (OC), organic molecular markers (e.g., levoglucosan, hopanes, polycyclic aromatic hydrocarbons), and secondary organic carbon (SOC) tracers were all significantly lower during the controlled period. After pollution controls ended, at Peking University, OC source contributions included gasoline and diesel engines (24%), coal combustion (6%), biomass burning (12.2%), vegetative detritus (2%), biogenic SOC (from isoprene, α-pinene, and β-caryophyllene; 7.1%), aromatic SOC (23%), and other sources not included in the model (25%). At Longgang after the controls ended, similar source contributions were observed: gasoline and diesel engines (23%), coal combustion (7%), biomass burning (17.7%), vegetative detritus (1%), biogenic SOC (from isoprene, α-pinene, and β-caryophyllene; 5.3%), aromatic SOC (13%), and other sources (33%). The contributions of the following sources were smaller during the pollution controls: biogenic SOC (by a factor of 10–16), aromatic SOC (4–12), coal combustion (1.5–6.8), and biomass burning (2.3–4.9). CMB model results and radiocarbon measurements both indicated that fossil carbon dominated over modern carbon, regardless of pollution controls. However, the CMB model needs further improvement to apportion contemporary carbon (i.e. biomass burning, biogenic SOC) in this region. This work defines the major contributors to carbonaceous PM2.5 in Shenzhen and demonstrates that control measures for primary emissions could significantly reduce secondary organic aerosol (SOA) formation.
Afficher plus [+] Moins [-]Stable isotope analyses of precipitation nitrogen sources in Guiyang, southwestern China
2017
Liu, Xue-Yan | Xiao, Hong-Wei | Xiao, Hua-Yun | Song, Wei | Sun, Xin-Chao | Zheng, Xu-Dong | Liu, Cong-Qiang | Koba, Keisuke
To constrain sources of anthropogenic nitrogen (N) deposition is critical for effective reduction of reactive N emissions and better evaluation of N deposition effects. This study measured δ¹⁵N signatures of nitrate (NO3⁻), ammonium (NH4⁺) and total dissolved N (TDN) in precipitation at Guiyang, southwestern China and estimated contributions of dominant N sources using a Bayesian isotope mixing model. For NO3⁻, the contribution of non-fossil N oxides (NOx, mainly from biomass burning (24 ± 12%) and microbial N cycle (26 ± 5%)) equals that of fossil NOx, to which vehicle exhausts (31 ± 19%) contributed more than coal combustion (19 ± 9%). For NH4⁺, ammonia (NH3) from volatilization sources (mainly animal wastes (22 ± 12%) and fertilizers (22 ± 10%)) contributed less than NH3 from combustion sources (mainly biomass burning (17 ± 8%), vehicle exhausts (19 ± 11%) and coal combustions (19 ± 12%)). Dissolved organic N (DON) accounted for 41% in precipitation TDN deposition during the study period. Precipitation DON had higher δ¹⁵N values in cooler months (13.1‰) than in warmer months (−7.0‰), indicating the dominance of primary and secondary ON sources, respectively. These results newly underscored the importance of non-fossil NOx, fossil NH3 and organic N in precipitation N inputs of urban environments.
Afficher plus [+] Moins [-]Spatio-temporal impact of salinated mine water on Lake Jormasjärvi, Finland
2019
Leppänen, Jaakko Johannes | Luoto, Tomi P. | Weckström, Jan
The salinization of freshwater environments is a global concern, and one of the largest sources of salinated water is the mining industry. An increasing number of modern mines are working with low grade sulfide ores, resulting in increased volumes of potentially harmful saline drainage. We used water monitoring data, together with data on sedimentary fossil remains (cladoceran, diatom and chironomid), to analyze the spatio-temporal (5 sampling locations and 3 sediment depths) impact of salinated mine water originating from the Talvivaara/Terrafame open cast mine on multiple components of the aquatic ecosystem of Lake Jormasjärvi, Finland. Lake Jormasjärvi is the fourth and largest lake in a chain of lakes along the path of the mine water. Despite the location and large water volume, the mine water has changed the chemistry of Lake Jormasjärvi, reflected in increased electrical conductivity values since 2010. The ecological impact is significant around the inflow region of the lake, as all biological indicator groups show a rapid and directional shift towards new species composition. There is a clear trend in improved water quality as one moves further from the point of inflow, and as one looks back in time. Our results show that salinated mine water may induce rapid and large scale changes, even far downstream along a chain of several sinking basins. This is of special importance in cases where large amounts of waste water are processed in the vicinity of protected habitats.
Afficher plus [+] Moins [-]Dual-carbon isotope constraints on source apportionment of black carbon in the megacity Guangzhou of the Pearl River Delta region, China for 2018 autumn season
2022
Jiang, Fan | Liu, Junwen | Cheng, Zhineng | Ding, Ping | Xu, Yuanqian | Zong, Zheng | Zhu, Sanyuan | Zhou, Shengzhen | Yan, Caiqing | Zhang, Zhisheng | Zheng, Junyu | Tian, Chongguo | Li, Jun | Zhang, Gan
Black carbon (BC) aerosol negatively affects air quality and contributes to climate warming globally. However, little is known about the relative contributions of different source control measures to BC reduction owing to the lack of powerful source-diagnostic tools. We combine the fingerprints of dual-carbon isotope using an optimized Bayesian Markov chain Monte Carlo (MCMC) scheme and for the first time to study the key sources of BC in megacity Guangzhou of the Pearl River Delta (PRD) region, China in 2018 autumn season. The MCMC model-derived source apportionment of BC shows that the dominant contributor is petroleum combustion (39%), followed by coal combustion (34%) and biomass burning (27%). It should be noted that the BC source pattern is highly sensitive to the variations of air masses transported with an enhanced contribution of fossil source from the eastern area, suggesting the important impact of regional atmospheric transportation on the BC source profile in the PRD region. Also, we further found that fossil fuel combustion BC contributed 84% to the total BC reduction during 2013–2018. The response of PM₂.₅ concentration to the ¹⁴C-derived BC source apportionment is successfully fitted (r = 0.90) and the results predicted that it would take ∼6 years to reach the WHO PM₂.₅ guideline value (10 μg m⁻³) for the PRD region if the emission control measures keep same as they are at present. Taken together, our findings suggest that dual-carbon isotope is a powerful tool in constraining the source apportionment of BC for the evaluations of air pollution control and carbon emission measures.
Afficher plus [+] Moins [-]Spatial variations in polycyclic aromatic hydrocarbons concentrations at surface sediments from the Cyprus (Eastern Mediterranean): Relation to ecological risk assessment
2013
Darılmaz, Enis | Kontaş, Aynur | Uluturhan, Esin | Akçalı, İdil | Altay, Oya
The objective of the present study was to evaluate the distribution, sources, origins, and environmental risk assessment of polycyclic aromatic hydrocarbons (16 US EPA priority pollutants) pollution in 23 surface sediments from Cyprus coast. The mean total polycyclic aromatic hydrocarbons (PAHs) concentrations in the sediments from Gemi Konagi, Girne and Gazi Magusa areas were found 47, 52 and 50ng/g, respectively. Molecular ratios and principle component analysis indicated that PAH pollution originated mainly from fossil sources, with higher pyrolytic contributions. The 2–3 ring PAHs were dominant in Cyprus sediments. Concentrations of PAHs observed in this study were compared with available soil quality guidelines and the concentrations were lower than the guideline values. The guideline values suggested that the Cyprus sediments were likely to be not contaminated by toxic PAH compounds.
Afficher plus [+] Moins [-]Agriculture, globalization, and ecological footprint: the role of agriculture beyond the tipping point in the Philippines
2022
Muoneke, Obumneke Bob | Okere, Kingsley Ikechukwu | Nwaeze, Chinwendu Nnamdi
This study is hinged on analyzing factors such as agriculture and globalization (de jure trade and financial) that threaten a sustainable environment using two proxies of ecological footprint: carbon and noncarbon ecological footprint in the Philippines while controlling for the influence of fossil to GDP, economic growth, urban population, and financial development using the autoregressive distributed lag (ARDL) framework. The result provides evidence of long‐run stable state among the variables. The result validates inverted U‐shaped pattern of EKC involving relationship between agricultural development and ecological footprint for the Philippines indicating that initially, ecological footprint increases as the agriculture develops and then declines as the agriculture matures to generate efficiency and low carbon. In addition, this study explores elasticities of the variables using ARDL, FMOLS, DOLS, and CCR procedure and found that de jure financial globalization exerts positive influence on ecological footprint in the long run. De jure trade globalization is found to be negative and significant in the long run. It is also found that agricultural level operates below the threshold level required to maximize the growth benefits of agricultural system towards mitigating environmental sustainability. Further empirical result shows a positive relationship between economic growth, fossil fuel, urban-population growth, and ecological footprint, and negative insignificant relationship between credit to private sector and ecological footprint. The government should optimize the use of agricultural land through well-articulated economic integration strategy fashioned to pave way for cleaner and low-carbon technologies sources like solar, geothermal, biomass, biogas, tidal power, photovoltaic, and wind energy in the agricultural production to avoid further deterioration of the environment.
Afficher plus [+] Moins [-]Retrospecting on resource abundance in leading oil-producing African countries: how valid is the environmental Kuznets curve (EKC) hypothesis in a sectoral composition framework?
2022
Onifade, Stephen Taiwo
Policymakers and authorities in Africa are often concerned about economic growth and stability owing to the long history of socioeconomic problems that have bedeviled the continent for years. However, increasing environmental degradation challenges in recent times beckons for adequate attention considering Africa’s vulnerability to climate change and environmental disasters. Thus, the current study examines the illustrious environmental Kuznets curve (EKC) hypothesis in a sectoral composition framework of fossil resources abundance among leading oil-producing African economies, including Algeria, Nigeria, Angola, and Egypt, using a combination of quantile regression (QR) approach and dynamic ordinary least square (DOLS) for data between 1995 and 2016. Based on the empirical results from the study, three main factors significantly increase environmental pollution through CO₂ emissions among the countries, namely: fossil energy consumption, income levels, and the shares of the manufacturing sector in the total gross domestic product (GDP). While income growth exacerbates pollution, the negative impacts of the income square were only significant at the lower and mid quantiles of the understudied periods in the QR estimates. Thus, the EKC hypothesis was not convincingly upheld for the countries as its validity demonstrates significant quantile effects. Furthermore, the tripartite causality nexus among real income, resource rent, and share of the service sector in GDP, which is unobserved in the share of the manufacturing sector, reflect the infamous Dutch disease argument among the resource-dependent countries. Hence, to promote environmental sustainability and address resource dependency toward the actualization of SDGs (1, 8, 12, and 13), the study recommends energy portfolios diversification alongside economic diversification.
Afficher plus [+] Moins [-]Chemical and structural aspects of fresh and fossil marine mollusc shells investigated by mid-infrared and near-infrared spectroscopy with the support of statistical and multivariate methods
2022
Mecozzi, Mauro | Fratte, Riccardo Delle | Pietroletti, Marco | Novelli, Fabrizio | Scacco, Umberto
In the present study, we applied Fourier transform infrared (FTIR) and Fourier transform near infrared (FTNIR) spectroscopy to investigate some specific structural aspects of Patella caerulea, Mytilus edulis, Ostrea edulis, and Calista chione shells sampled in different sites. Moreover, for Ostrea edulis and Calista chione, the present study also included fossil samples. As far as FTIR spectroscopy is concerned, the support of statistical and multivariate methods such as the average spectrum (AV), spectral deconvolution, and two-dimensional correlation analysis (2DCOS) allowed to detect structural differences existing within the same mollusc species as a function of the sites they come. These differences can be reasonably linked to the local environmental conditions, which affect the biomineralization pattern of shell formation and growth. These structural differences are related to the calcite, aragonite, Mg-calcite contents, and interactions, as presently observed for fresh and fossil shells. The application of 2DCOS and deconvolution to FTIR spectra also showed the role of the amorphous calcium carbonate (ACC) in the structural characterization of shells, then suggesting the use of a new parameter, the calcite and aragonite to ACC (CAACC) ratio, as a new measurement for the structural characterization of shells. At last, FTNIR spectroscopy allowed detecting the presence of α-helix and β-sheet protein structures in the shells. The results of this study show that also FTIR and FTNIR spectroscopy are able to discern differences in structural characteristics of mollusc shells, a field of environmental studies where scanning electron microscopy and X-ray diffraction are the more widely used methods.
Afficher plus [+] Moins [-]Life cycle assessment of a wind farm in Turkey
2022
Ozsahin, Buse | Elginoz, Nilay | Germirli Babuna, Fatos
The aim of this study is to investigate the environmental impacts of a full-scale wind farm using life cycle assessment methodology. The facility in question is an onshore wind farm located in Turkey with a total installed capacity of 47.5 MW consisting of 2.5 MW Nordex wind turbines. Hub height and rotor diameter of the wind turbines are 100 m. The system boundary is defined as material extraction, part production, construction, operation and maintenance and decommissioning phases of the wind farm. The functional unit is 1-kWh electricity produced. Environmental impacts are mainly generated by manufacturing and installation operations. Steel sheet usage in tower manufacturing is the main contributor to abiotic depletion of fossil resources, acidification, eutrophication, global warming and marine aquatic ecotoxicity potentials. Apart from ozone layer depletion, end-of-life phase decreases the environmental impacts due to metal recycling. Metal recycling ratio scenario results show that when the recycling ratio decreases from 90 to 20%; increases of 110%, 102%, 92% and 87% are observed in acidification, terrestrial ecotoxicity, marine aquatic ecotoxicity and global warming potentials, respectively. In the baseline, the main parts which are manufactured in Germany are transported by sea to Turkey. Transportation scenario involves shifting the manufacturing of main parts to Turkey then transporting these parts by trucks to the farm. This conversion causes increases of 31%, 35% and 27% in abiotic depletion of fossil resources, freshwater aquatic ecotoxicity and global warming potentials, respectively, while causing decreases of 11% and 4% in acidification and eutrophication potentials generated by transportation activities, respectively.
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