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An assessment of the inhalation bioaccessibility of platinum group elements in road dust using a simulated lung fluid
2018
Wiseman, Clare L.S. | Niu, Jianjun | Lévesque, Christine | Chénier, Marc | Rasmussen, Pat E.
Metal enrichment of road dust is well characterized but available data on the bioaccessibility of metals in particle size fractions relevant to human respiratory health remain limited. The study goal was to investigate the bioaccessibility of platinum group elements (PGE), which are used as catalysts in automotive exhaust converters, in the inhalable fraction of road dust. Street sweepings were provided by the City of Toronto, Canada, collected as part of its Clean Roads to Clean Air program.The particle size relevance of road dust for inhalation exposures was confirmed using a laser diffraction particle size analyzer (mean Dx(50): 9.42 μm). Total PGE were determined in both bulk and inhalable fractions using nickel sulfide (NiS) fire-assay and instrumental neutron-activation analysis (INAA). PGE lung solubility was examined for the inhalable fraction using Gamble’s extraction. Sample digests were co-precipitated with Te-Sn, to pre-concentrate and isolate PGE, prior to their measurement using inductively coupled plasma mass spectrometry (ICP-MS).Total PGE concentrations were enriched in the inhalable fraction of road sweepings. Geomean concentrations in the inhalable fraction were: palladium (Pd) (152 μg/kg), platinum (Pt) (55 μg/kg), rhodium (Rh) (21 μg/kg) and iridium (Ir) (0.23 μg/kg). Osmium (Os) concentrations were below the limit of detection (LOD). Bioaccessible PGEs (n = 16) using Gamble’s solution were below LOD for Ir and ruthenium (Ru). For the remainder, the geomean % bioaccessibility was highest for platinum (16%), followed by rhodium (14%) and palladium (3.4%). This study provides evidence that PGE in road dust are bioaccessible in the human lung.
اظهر المزيد [+] اقل [-]Bioindication of atmospheric trace metals – With special references to megacities
2011
Markert, Bernd | Wuenschmann, Simone | Fraenzle, Stefan | Graciana Figueiredo, Ana Maria | Ribeiro, Andreza P. | Wang, Meie
After considering the particular problems of atmospheric pollution in megacities, i.e. agglomerations larger than 5 mio. inhabitants, with urbanization of World’s population going on steadily, possibilities of active biomonitoring by means of green plants are discussed. Based on specific definitions of active and passive bioindication the chances of monitoring heavy metals in Sao Paulo megacity were demonstrated (first results published before). This is to show that there is need for increased use of bioindication to tackle the particular problems of megacities concerning environmental “health”, the data to be processed according to the Multi-Markered-Bioindication-Concept (MMBC). Comparison to other work shows this approach to be reasonable.
اظهر المزيد [+] اقل [-]Use of moss biomonitors for turbulent transport coefficient estimation for industrial emissions
2017
Ryzhakova, Nadezhda K. | Borisenko, Alexei L. | Babicheva, Valentina O.
The important mechanism transporting substances in the surface layer of the atmosphere is turbulent diffusion. The intensity of turbulent transport is characterized by the turbulent diffusion coefficient. Calculation is a difficult task without a unique characterization. Distinguished turbulent models of atmospheric flow have been developed for particular atmospheric states and simple landscapes. These restrictions complicate the use of such models when assessing the distribution of industrial emissions in the atmosphere. The aims of the present work are to (i) develop a semi-empirical method for estimating the turbulent diffusion coefficient of the emissions of large industries, and (ii) study the turbulence intensity dependence of fundamental factors: the wind speed and landscape. The method relies on the distribution function of the concentration of contaminants measured along any direction of the altitude of a point source. Epiphytic mosses (Pylaisia polyantha, Sanionia uncinata) were used with an exposure time of 3 years. The chemical contents of the mosses were determined by neutron activation analysis and atomic emissive spectrometry. It is shown that in the territories of the coal-fired thermal power station and aluminum plant, the average values of the turbulent transport coefficient at heights above 1 m are k1¯=0.15 m2/s and k1¯=0.02 m2/s respectively. High turbulence within the location of the thermal power station is explained by obstacles of various heights and a higher wind speed. The proposed method is useful for the estimation and forecast of the spatial distribution of emissions from large industries and for determining the zones of their influence.
اظهر المزيد [+] اقل [-]Characterization of major and trace elements in coastal sediments along the Egyptian Mediterranean Sea
2022
Badawy, Wael | Elsenbawy, Ahmed | Dmitriev, Andrey | El Samman, Hussein | Shcheglov, Alexey | El-Gamal, Ayman | Kamel, Nariman H.M. | Mekewi, Mohammed
The present study was conducted to provide a comprehensive picture of marine sediment characterization in terms of geochemistry and the extent of pollution. A total of 99 surface coastal sediments were collected from coastal areas along with the Egyptian Mediterranean Sea. The samples were analyzed by neutron activation analysis (NAA) and the mass fractions in mg/kg of 39 trace elements were determined. The normalized mass fractions show significant amounts of Cl (26.4%), Sn (12%), Zr (7.3%), Hf (5.9%), Ti (4.7%), Cr (4.2%), Ca (3.4%), Si (3.1%), Sr (2.9%). The mass fractions of the rare earth elements REEs (La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, and Lu) are almost double compared to literature data. Principal component analysis PCA and positive matrix factorization PMF were used to decipher the sources of pollutions. Sediment quality was quantified using different pollution indices such as enrichment factor (EF), modified pollution index (MPI), pollution load index (PLI) and the new approach to calculate total pollution index (TPI). The results of the study recognized four locations with significant pollution, namely the coastal area along Al Manzalah Lake, the Nile River estuaries at Ras Elbar and its western coastal area, at the outlet of Elbrullus Lake, and finally the Abu Qir Bay. The obtained result can serve as a geochemical background of the sediments of the study coastal area, which allows following the quality of marine sediments along with the Egyptian Mediterranean Sea.
اظهر المزيد [+] اقل [-]Evaluation of the elemental pollution status of Jamaican surface sediments using enrichment factor, geoaccumulation index, ecological risk and potential ecological risk index
2020
Williams, Jhénelle A. | Antoine, Johann
Surficial marine sediments were sampled along the south-east coast and in Discover Bay Jamaica. Total elemental composition was determined for the sediments using three techniques. Total mass fractions of Al, As, Br, Ce, Co, Cr, Cs, Eu, Fe, La, Mn, Sb, Sc, Th, U, V, and Zn were determined using instrumental neutron activation analysis; Cu, Ni, Pb, Sr and Zr using energy dispersive X-ray fluorescence; and Hg using a direct mercury analyser. Potential anthropogenic hotspots were assessed using indices including enrichment factor (EF), geoaccumulation index (Igₑₒ), ecological risk (Eᵣ) and potential ecological risk index (Rᵢ). The quality of the sediments was also assessed using the sediment quality guidelines (SQGs). Temperature, pH, salinity, dissolved oxygen and organic carbon content (OC) were determined to assess variation across sample sites. Results indicated moderate to severe ecological risk at sites in Port Royal and Discovery Bay with ecological risk values as high as 381.9.
اظهر المزيد [+] اقل [-]The sources and ecological risk assessment of elemental pollution in sediment of Linggi estuary, Malaysia
2018
Elias, Md Suhaimi | Ibrahim, Shariff | Samuding, Kamarudin | Rahman, Shamsiah Ab | Hashim, Azian
In this study, concentrations of heavy metals, rare earth elements (REEs), Uranium (U) and Thorium (Th) of the actinide group were determined from Linggi estuary sediment samples by neutron activation analysis (NAA) and inductive coupled plasma - mass spectrometry techniques. The geo-accumulation (Igeo) and ecological risk index (Ri) values were calculated to identify the quality status of Linggi estuary sediments. Results indicated Linggi estuary was polluted by arsenic (As), lead (Pb) and antimony (Sb). REEs, U and Th showed significant increase of concentration in Linggi estuary sediments. Ri of Linggi estuary was categorised as low to considerable ecological risk, which indicates no significant to moderate effect on the majority of the sediment-dwelling organisms. Correlation matrix and principal component analysis assessed pollution sources to be both natural and anthropogenic.
اظهر المزيد [+] اقل [-]Assessment of vertical element distribution in street canyons using the moss Sphagnum girgensohnii: A case study in Belgrade and Moscow cities
2016
Goryainova, Zoya | Vuković, Gordana | Uros̆ević, Mira Aničić | Vergel, Konstantin | Ostrovnaya, Tatyana | Frontasyeva, Marina | Zechmeister, Harald
Sphagnum girgensohnii moss bags were used to study the small-scale vertical distribution of some major and trace elements in different types of street canyons (regular, deep and avenue types) in Belgrade and Moscow urban area. The exposure time was 10 weeks during the summer of 2011. The exposure of moss bags was at three different levels to test differences in deposition patterns according to height. The differences between the street and off-street side in the vertical element distribution in Moscow were tested too. The concentration of 25 major and trace elements in moss was determined by instrumental neutron activation analysis. The results showed that the accumulation of elements in the exposed moss bags were higher in deep and regular street canyons in comparison to that of the avenue type, the latter even with a higher traffic flow. The element concentrations were the highest at the lowest heights compared to those of the upper floors. For most determined elements the concentrations were lower on the off-street avenue side compared to the on-street side for all heights of moss exposure. The results obtained indicate that S. girgensohnii is sensitive to small-scale variations of the total concentrations of elements.
اظهر المزيد [+] اقل [-]Heavy metal contamination and ecological risk assessment in water and sediments of the Halda river, Bangladesh: A natural fish breeding ground
2020
Islam, Mohammad Amirul | Das, Biplob | Quraishi, Shamshad Begum | Khan, Rahat | Naher, Kamrun | Hossain, Syed Mohammod | Karmaker, Shanjib | Latif, Shaikh Abdul | Hossen, Mohammad Belal
This study reports the mass fractions of Al, Cr, Mn, Fe, Co, Zn, As, Ni, Cu, Cd, Hg, and Pb in water and sediments of the Halda river, Bangladesh, and studies the distribution, contamination, and potential ecological risks of the metals and metalloid. The average mass fractions of As, Cd, and Pb are relatively higher in sediments compared to those in background values, whereas Al, Fe, Mn, and Pb concentration fractions in water are higher than the international guideline values. The results of the different contamination indices indicate that Halda river sediments are minorly contaminated by As and Pb and moderately to considerably contaminated by Cd. The ecological risk assessments indicate considerable to high ecological risk due to Cd. Multivariate statistical analysis reveals the origin of the contaminants in the river, and indicate that Cr, Zn, Pb, and Cd are from anthropogenic activities while the other metals originate from natural lithogenic actions.
اظهر المزيد [+] اقل [-]Contamination and ecological risk assessment of trace elements in sediments of the rivers of Sundarban mangrove forest, Bangladesh
2017
Islam, M.A. | Al-mamun, A. | Hossain, F. | Quraishi, S.B. | Naher, K. | Khan, R. | Das, S. | Tamim, U. | Hossain, S.M. | Nahid, F.
In this study, total concentrations of 16 trace elements (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Sb, Hg, Pb, Th and U) in sediments of the rivers of the Sundarban mangrove forest, after the catastrophic oil spill accident in the Sela river of Sundarban, were determined. The overall mean concentrations of V, Cr, Fe and Cd in surface sediments of the Sundarban are remarkably higher than available literature data of those elements. Trace element contamination assessment, using different environmental contamination indices, reveals that As, Sb, Th and U are low to moderately contaminated while Cd is moderately to severely contaminated in the sediments of this area. The multivariate statistical analyses were applied to reveal the origin and behavior of the elements during their transport in the mangrove ecosystem. High Cr, Ni, Cu and As concentrations suggest the risk of potentially adverse biological effects in the ecosystem.
اظهر المزيد [+] اقل [-]Levels, spatial variation and compartmentalization of trace elements in brown algae Cystoseira from marine protected areas of Crimea (Black Sea)
2015
Kravtsova, Alexandra V. | Milchakova, Nataliya A. | Frontasyeva, Marina V.
Levels of Al, Sc, V, Co, Ni, As, Br, Rb, Sr, Ag, Sb, I, Cs, Ba, Th and U that were rarely or never studied, as well as the concentrations of classically investigated Mn, Fe and Zn in brown algae Cystoseira barbata C. Ag. and Cystoseira crinita (Desf.) Bory from the coastal waters of marine protected areas (Crimea, Black Sea), were determined using neutron activation analysis. Spatial variation and compartmentalization were studied for all 19 trace elements (TE). Concentrations of most TE were higher in “branches” than in “stems”. Spatial variations of V, Co, Ni and Zn can be related to anthropogenic activities while Al, Sc, Fe, Rb, Cs, Th and U varied depending on chemical peculiarities of the coastal zone rocks. TE concentrations in C. crinita from marine protected areas near Tarkhankut peninsula and Cape Fiolent, identified as the most clean water areas, are submitted as the background concentrations.
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