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Oil sands development and its impact on atmospheric wet deposition of air pollutants to the Athabasca Oil Sands Region, Alberta, Canada
2015
Lynam, Mary M. | Dvonch, J Timothy | Barres, James A. | Morishita, Masako | Legge, Allan | Percy, Kevin
Characterization of air pollutant deposition resulting from Athabasca oil sands development is necessary to assess risk to humans and the environment. To investigate this we collected event-based wet deposition during a pilot study in 2010–2012 at the AMS 6 site 30 km from the nearest upgrading facility in Fort McMurray, AB, Canada. Sulfate, nitrate and ammonium deposition was (kg/ha) 1.96, 1.60 and 1.03, respectively. Trace element pollutant deposition ranged from 2 × 10−5 - 0.79 and exhibited the trend Hg < Se < As < Cd < Pb < Cu < Zn < S. Crustal element deposition ranged from 1.4 × 10−4 – 0.46 and had the trend: La < Ce < Sr < Mn < Al < Fe < Mg. S, Se and Hg demonstrated highest median enrichment factors (130–2020) suggesting emissions from oil sands development, urban activities and forest fires were deposited. High deposition of the elements Sr, Mn, Fe and Mg which are tracers for soil and crustal dust implies land-clearing, mining and hauling emissions greatly impacted surrounding human settlements and ecosystems.
Afficher plus [+] Moins [-]Organophosphorus flame retardants and persistent, bioaccumulative, and toxic contaminants in Arctic seawaters: On-board passive sampling coupled with target and non-target analysis
2019
Gao, Xiaozhong | Huang, Peng | Huang, Qinghui | Rao, Kaifeng | Lu, Zhibo | Xu, Yiping | Gabrielsen, Geir Wing | Hallanger, Ingeborg | Ma, Mei | Wang, Zijian
Organic pollutants in the Arctic seas have been of concern to many researchers; however, the vast dynamic marine water poses challenges to their comprehensive monitoring within appropriate spatial and temporal scales in the Arctic. In this study, on-board passive sampling of organic pollutants using a self-developed device coupled with triolein-embedded cellulose acetate membranes (TECAMs) was performed during an Arctic cruise. The TECAM extracts were used for target analysis of organophosphorus flame retardants (PFRs), and non-target screening of persistent, bioaccumulative, and toxic (PBT) contaminants using two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC-TOFMS). Sixteen chemicals were screened out as PBT contaminants from the 1500 features in the non-target analysis and further identified. Consequently, two chlorinated PFRs (tris(chloroisopropyl)phosphate and tris(1,3-dichloroisopropyl)phosphate) and four PBT contaminants (4-tert-butylphenol, 2-isopropylnaphthalene, 1,1,3-trimethyl-3-phenylindane, and 1-phenylnonan-1-one) were accurately quantified, with the temporally and spatially integrated concentrations ranging from 0.83 ng L⁻¹ to 20.82 ng L⁻¹ in the seawaters. Sources and transport of the contaminants were studied, and ocean current transport (West Spitsbergen Current, WSC) and local sources (human settlement, Arctic oil exploitation, and petroleum fuel emissions) were found to contribute to the presence of the different contaminants. Finally, annual transport fluxes of the contaminants from the North Atlantic to the Arctic Ocean by WSC were estimated, and the results indicate that their hazard to the Arctic should be concerned.
Afficher plus [+] Moins [-]Levels of polycyclic aromatic hydrocarbons in Canadian mountain air and soil are controlled by proximity to roads
2009
Choi, Sung-Deuk | Shunthirasingham, Chubashini | Daly, Gillian L. | Xiao, Hang | Lei, Ying D. | Wania, Frank
Concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in soil and XAD-based passive air samples taken from a total of 22 sites along three transects (Revelstoke, Yoho, and Observation, 6–8 sites for each transect) in the mountains of Western Canada in 2003–2004. Median concentrations in air (4-ring PAHs: 33 pg/m3) were very low and comparable to those in global background regions such as the Arctic. Low median soil concentrations (16 EPA PAHs: 16 ng/g dry weight) and compositional profiles dominated by naphthalene and phenanthrene are similar to those of tropical soils, indicative of remote regions influenced mostly by PAHs from traffic and small settlements. Comparing levels and composition of PAHs in soils between and along transects indeed suggests a clear relationship with proximity to local sources. Sampling sites that are closer to major traffic arteries and local settlements have higher soil concentrations and a higher relative abundance of heavier PAHs than truly remote sites at higher elevations. This remains the case when the variability in soil organic carbon content between sites is taken into account. Both air/soil concentration ratios and fugacity fractions suggest atmospheric net deposition of four-ring PAHs to soils. Soil and air monitoring of PAHs along three transects in the mountains of Western Canada reveals the influence of local emissions.
Afficher plus [+] Moins [-]Fatty acid-based index development in estuarine organisms to pinpoint environmental contamination
2022
Fonseca, Vanessa F. | Duarte, Irina A. | Feijão, Eduardo | Matos, Ana Rita | Duarte, Bernardo
Estuaries have long been preferred areas of human settlement, where multiple anthropogenic activities take place, which have contributed to a significant decrease in environmental quality of these ecosystems. Accordingly, environmental monitoring and management have long relied on the development of tools that summarize and simplify complex information and provide direct interpretation of quality status. Here, the fatty acid profiles of three abundant estuarine species, namely Hediste diversicolor, Carcinus maenas and Pomatoschistus microps, were used to develop and validate a multimetric index, based on the Euclidean dissimilarities of profiles between sites, in response to contamination gradient in a large urban estuary. Spatial differences were generally related to unsaturated fatty acids (mono- and polyunsaturated, of the n−3 and n−6 series) in all species, albeit more pronounced in P. microps. Multivariate models returned high classification accuracies for the three sampled sites, varying from 73.3% in the invertebrate species to 100.0% in the fish species. Results show the applicability of the developed FA-based index, particularly due to the easy of communication, for managers and the public alike, but also highlight the need for prior validation on species suitability or sensitivity to depict environmental contamination.
Afficher plus [+] Moins [-]First assessment of anthropogenic marine debris in mangrove forests of Mauritius, a small oceanic island
2021
Seeruttun, Linisha Devi | Raghbor, Phanesh | Appadoo, Chandani
We evaluated the status of anthropogenic marine debris (AMD) in two natural mangrove forests on Mauritius, one of which in proximity to human settlement (Mahebourg) and the other more remote (Ferney). AMD was collected monthly from October to December 2018 in 1500 m² at both sites and classified into material composition and their potential sources. In all, 2127 items (150.07 kg) was sampled at Mahebourg and 1098 items (43.71 kg) at Ferney. In line with global studies, plastic made up most of the debris in terms of both count (42.92%, 43.66%) and total weight (40.65%, 32.08%) at Mahebourg and Ferney respectively. Most debris originated from shoreline and recreational activities. This work sets a baseline to assess impacts of AMD on mangroves, public awareness required and future strategies for waste monitoring and management in mangroves that may be applied both locally and on other small islands.
Afficher plus [+] Moins [-]Tracing the sources of lead (Pb) in Brunei Bay, Borneo by using integrated spectrometry ICP-MS and chemometric techniques
2017
Adiana, Ghazali | Juahir, Hafizan | Joseph, Bidai | Shazili, Noor Azhar Mohamed
The present study aims to define the possible sources that contribute to the level of Pb into the Brunei Bay, Borneo. The cluster analysis has classified the bay into the northern part with heavy and agriculture-related industries; the southern area with a moderate rural human settlement as well as the southwestern area with a more pristine environment and a low level of human settlement. The score plot of spatial discriminant analysis verified a significant influence of the river system toward the estuary, whereas the temporal discriminant analysis has discriminated the seasonal changes. In comparison to elsewhere, the stable Pb isotopic ratios in Brunei Bay showed a fingerprint similar to coal-related sources and of aerosol input. Briefly, even though Pb in the Brunei Bay ecosystem proved to be at a low level, the stable Pb isotopic ratios showed that human and industrial activities are slowly contributing Pb into the bay ecosystem.
Afficher plus [+] Moins [-]Paleolimnological Records of Nutrient and Metal Profiles in Prehistoric, Historic and Modern Sediments of Three Lakes in North-eastern Germany
2007
Selig, U. | Leipe, T (Thomas) | Dörfler, W (Walter)
Sedimentprofiles of the last 4,000-14,000 years are presented from three dimictic lakes in Mecklenburg-Vorpommern (North-eastern Germany). Sedimentological composition, major trace elements and nutrients as well as parameter for core chronology (palynology, ¹⁴C-AMS) were investigated in order to reconstruct the historical development of the lakes during the Holocene. Palynological results reflect different human settlement phases and environmental changes from the late Pleistocene to the Subatlantic. Since the Middle Ages, a permanent settlement in the catchment area resulted in higher sedimentation rates in the three lakes. Variations in sediment composition like organic matter, carbonate and mineral content were caused by different land management techniques and natural changes in the catchment area. The phosphorus accumulation increased in the upper sediment layers, but the highest phosphorus accumulations were not found in the industrial phase, but in older sediments associated with human settlement activities in the catchment area. The heavy metals lead and zinc increase in the uppermost part of all three lakes reflecting the atmospheric anthropogenic input during the last 150-200 years.
Afficher plus [+] Moins [-]Adaptability evaluation of human settlements in Chengdu based on 3S technology
2022
Chen, Wende | Zhu, Kun | Wu, Qun | Cai, Yankun | Lu, Yutian | Wei, Jun
This study aims to showcase the adaptability evaluation of human settlements in Chengdu with the use of 3S technology. Chengdu was selected as the research object; natural eco-environmental factors such as terrain fluctuations, temperature and humidity, vegetation type, land use, and vegetation cover were analyzed, together with human disturbance factors such as traffic and gross domestic product (GDP); and the index weights were calculated by analytic hierarchy process (AHP). The evaluation model of Chengdu’s residential environment adaptability was constructed based on the analysis carried out by the 3S technology: projection transformation, remote sensing interpretation, information extraction, and analysis. The results of the analysis reflected the zoning and spatial distribution characteristics of Chengdu’s residential environment adaptability, and show that (1) the adaptability index of Chengdu’s human settlement environment is between 15.98 and 76.75, and the suitability of human settlement environment is seen gradually decreasing from the middle, where it is the highest, when moving to the west and to the east of Chengdu; (2) according to the present situation, the suitability index can be divided into high-grade suitable areas, relatively high-grade suitable areas, moderately suitable areas, and low suitable areas; (3) the correlation between the spatial distribution of Chengdu population and each index factor is as follows: per capita GDP > topographic relief > temperature and humidity > vegetation coverage > traffic network density > land use > hydrological factors; (4) there is a good correlation between Chengdu’s human settlements suitability index and the present population density grid layer, and its correlation coefficient is 0.7326; and (5) the leading impact indicators of human settlements are different in different regions. The results show that the natural environmental conditions in Chengdu are superior and that the ecological environmental quality is relatively stable, but the human settlement suitability index is relatively low in the southeast and Longmenshan areas of Chengdu.
Afficher plus [+] Moins [-]Evaluation of the metal concentrations of wild mushroom species with their health risk assessments
2021
Sarikurkcu, Cengiz | Yıldız, Dilek | Akata, Ilgaz | Tepe, Bektas
The ability of mushrooms to accumulate heavy metals has increased concerns over their toxic effects on human health in recent years. The aim of this study was to determine the metal contents (Zn, Fe, Co, Mn, Cu, Pb, Ni, and Cd), daily intake of metal (DIM) and health risk index (HRI) values of nineteen different mushroom species (edible, inedible, and poisonous) collected from Uzungol, Trabzon (Turkey). Although the area where mushrooms were collected has the status of “Natural Park,” there has been an excessive human settlement in recent years. Elemental analyses have shown that Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni concentrations in mushrooms were in the following ranges: 49.0–1713.0, 3.0–425.0, 3.0–154.0, 16.0–134.0, 0.17–1.79, 0.28–7.88, 0.07–5.68, and 0.24–6.82 mg/kg dry weight, respectively. As a result of DIM analysis, while it was determined that the daily consumption of Hygrophorus pudorinus, Meripilus giganteus, and Sarcodon imbricatus was safe for all the metals examined, HRI analysis showed that only M. giganteus and S. imbricatus can be consumed safely. The content of Cd was found to be above the legal limits determined by the competent authorities. According to Pearson correlation analysis, the correlations between Fe-Pb, Cu-Zn, Cd-Co, Pb-Co, Cd-Fe, Co-Fe, Cd-Pb, and Fe-Mn pairs were statistically significant (p < 0.01). Although the data obtained from this study did not provide clear data on environmental pollution in the area where the samples were collected, it was concluded that the competent authorities should take measures regarding possible environmental pollution at this location.
Afficher plus [+] Moins [-]Metal concentration and health risk assessment of fifteen wild mushrooms collected from the Ankara University Campus (Turkey)
2020
Sarikurkcu, Cengiz | Sarikurkcu, Rifat Tayyib | Akata, Ilgaz | Tepe, Bektas
The aim of this study is to analyze Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni contents of Cyclocybe cylindracea, Armillaria mellea, Bjerkandera adusta, Rheubarbariboletus armeniacus, Coprinellus disseminatus, C. micaceus, C. comatus, Inonotus hispidus, Lepista nuda, Leucoagaricus leucothites, Pleurotus ostreatus, Cerioporus squamosus, Schizophyllum commune, Scleroderma verrucosum, and Trametes trogii collected from the Ankara University Besevler 10th Year Campus (Turkey), an area where human settlement and traffic are intense. In addition to the elemental analysis, the daily intake of metal (DIM) and health risk index (HRI) values of the edible ones were also calculated. Fe, Mn, Cu, Zn, Co, Cd, Pb, and Ni concentrations of the samples were found to be 112.0–5079.0, 3.0–124.0, 4.0–77.0, 2.0–196.0, 0.18–2.98, 0.18–5.3, 0.04–10.98, and 0.22–8.23 mg/kg dry weight, respectively. As a result of DIM and HRI analysis, C. cylindracea, L. nuda, and C. squamosus were found to be within the reference dose limits determined by competent authorities and can be safely consumed in terms of all metals studied. However, the Cd, Co, and Fe contents of C. micaceus were found to be above 1.0 (1.06, 4.25, and 7.06, respectively). In addition, it has been found that A. mellea, R. armeniacus, C. comatus, L. leucothites, and P. ostreatus are toxic in terms of Cd/Co, Fe/Pb, Co/Fe, Cd, and Fe contents, respectively. As the area in question is a traffic intensive area, it has been concluded that the emissions of the vehicles should be controlled in terms of legal limits and that the consumption of some mushrooms in this region should not be preferred until necessary measures are taken.
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