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Detecting atmospheric pollution in surface soils using magnetic measurements: A reappraisal using an England and Wales database
2009
Blundell, A. | Hannam, J.A. | Dearing, J.A. | Boyle, J.F.
Industrial activity such as burning of fossil fuels produces magnetically enhanced particulates. These particulates consist of coarse-grained multidomain and stable single domain magnetic minerals. Two threshold values of low field magnetic susceptibility (XLF) and frequency dependent susceptibility percentage (XFD%) discriminate ferrimagnetic minerals of these sizes and can act as a tracer of magnetic pollution. Application of the thresholds to a magnetic topsoil data set (n = 5656 across England and Wales) revealed 637 samples potentially dominated by pollution particulates. The magnetic parameters of these samples display a negative correlation with distance to urban areas and positive correlations with metals associated with anthropogenic activity (Cu, Pb, and Zn). Results of experimentation with threshold values and modelling of magnetic anomalies suggest that regional factors such as geology and potential for pedogenic secondary magnetic enhancement should be considered when setting threshold values.
Mostrar más [+] Menos [-]Chemical Composition of PM₁₀ and PM₂.₅ and Seasonal Variation in South Brazil
2009
Teixeira, Elba Calesso | Meira, Lindolfo | Santana, Eduardo Rodrigo Ramos de | Wiegand, Flavio
This paper presents experimental data on particulate matter (PM₁₀ and PM₂.₅) in the atmosphere of Candiota--South Brazil. Samples were collected using stacked filter units equipped with polycarbonate filters, which separate particles into two fractions: coarse 10-2.5 μm and fine <2.5 μm. The particulate matter was collected from January 2003 to September 2004 at three sampling sites: Acegua, 8 de Agosto, and Três Lagoas. The collected material was analyzed for Na, Mg, Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Br, Mo, Hg, and Pb, using particle-induced X-ray emission technique. Seasonal variation of the chemical elements with the size fraction was assessed. The elements K, Ca, Si, Ti, Fe, and Mn showed similar seasonal variability in the fine and coarse fractions with a low enrichment factor (<1.0) in both fractions, except for Mn and K, indicating common sources (soil dust, fly ash). Chemical species showing seasonal variability and high values of enrichment factor in fine fractions may indicate an anthropogenic origin.
Mostrar más [+] Menos [-]Model Analysis of PM₁₀ Concentration Variations Over a Mineral Products Industrial Area in Saraburi, Thailand
2009
Pimonsree, Sittichai | Wongwises, Prungchan | Pan-Aram, Rudklao | Zhang, Meigen
Air pollution associated with particulate matters is a serious problem in the mineral products industrial area (MPIA) in Saraburi, central Thailand. PM₁₀ concentrations monitored at Nah Phra Laan station located in the MPIA show that PM₁₀ levels exhibit strong seasonal variations; the number of days in 2005 that PM₁₀ concentrations exceeded the daily National Ambient Air Quality Standard of 120 μg/m³ were 58%, 29%, and 12% in the winter, rainy, and summer seasons, respectively. In this paper, the Hybrid Particle And Concentration Transport (HYPACT) model with meteorological fields from the Regional Atmospheric Modeling System (RAMS) was applied to Saraburi to investigate the impacts of meteorological parameters upon seasonal variations in PM₁₀ concentration. Analysis of model results shows that daily average PM₁₀ concentrations exceeding 200 μg/m³ are found in the downwind direction of emission sources and their horizontal gradients are strong. Hourly PM₁₀ concentrations exhibit obvious diurnal variation with maximum values in wintertime at around 2000-2100 local standard time in association with low ventilation with light wind speed and weak vertical mixing, while in the rainy season, they are generally higher in the daytime than in the nighttime, as that mixing height in cloudy days is low in daytime whereas emission rates are high during working time.
Mostrar más [+] Menos [-]Atmospheric Transfer and Deposition Mechanisms of ²¹⁰Pb Aerosols onto Forest Soils
2009
Likuku, Alfred S
Activities of ²¹⁰Pb carrier aerosols in an age-graded Sitka spruce conifer, three deciduous (oak, lime and sycamore) foliage and in rain and throughfall samples have been measured during the period of 2001-2002. The ²¹⁰Pb concentrations in the age-graded Sitka leaf needles have shown to accumulate until a steady state between accretion and loss of particulate matter is maintained with time. Similarly, the concentrations of ²¹⁰Pb on deciduous tree leaves increased with time until the leaves began to senesce. The ²¹⁰Pb inventory in bulk precipitation was significantly (r ² = 0.99; P < 0.001) large compared with that in throughfall samples, as indicated by a ratio of 1 to 0.1 of ²¹⁰Pb deposition in bulk precipitation to throughfall. This suggests that ²¹⁰Pb is retained in the Sitka spruce foliage during deposition until transfer to the ground mainly through litterfall. These findings suggest that the presence of woodland is responsible for enhanced ²¹⁰Pb deposition fluxes beneath wooded areas relative to open grassland soils.
Mostrar más [+] Menos [-]A Valuation of the Influence of Particulate Atmospheric Aerosol in Constructions of the Cultural and Architecture Patrimony of the Urban Area of Castellon (NE, Spain)
2009
Jordan, M. M. | Sanfeliu, T. | Gómez, E. T. | Pallarés, S. | Vicente, A. B.
The constructions of Cultural and Architecture Patrimony are influenced by pollutants. Many of degenerative processes in the materials which constitute them have their origin in pollutants. That is the reason why a physical-chemical characterisation of the particulate pollutants in the air has been carried out. The deposition and, as a consequence of that, the interaction of the pollutants with the different materials of the monuments depend on the reactivity of the chemical elements that form the atmospheric particulate. Studies of both, bulk dust deposition and total suspended matter, a mineralogical and chemical characterisation of them have been made. Lastly, starting from these data, it can be established that the interactions and degenerative processes are taking place in the monuments of the studied locations. In the present work, the methodology carried out in the study of the particulate atmospheric pollutants, which are capable of accumulating on monuments and buildings with artistic and historical interest in the area of Castellon, is displayed. By means of a network of captors, important samples of sedimentary and suspension atmospheric pollutants, total suspension particles (TSP) were obtained. Firstly, by gravimetric methods, we have obtained the concentration levels of these kinds of pollutants in milligrams per day in busk dust samples and micrograms per cubic meter in TSP. Due to the fact that the corrosivity of these pollutants fundamentally depends on their compositions, the study has been completed with a mineralogical and chemical characterisation. By X-ray diffraction and scanning electron microscopy, we have analysed the particles of the two kinds of samples. The chemical analysis was carried out by inductively coupled plasma-atomic spectroscopy and inductively coupled plasma-mass spectrometry (multielement analysis techniques) in TSP samples and in the soluble fraction of the depositing particulate matter. The results have shown as main compounds: clay minerals, calcite, and carbonaceous matter coming from non-perfect combustion of vehicles. The chemical analysis indicates a high Ca/S ratio and high levels of concentration in chemical elements associated to this representative industrial cluster of ceramics industry in Europe.
Mostrar más [+] Menos [-]A Simple Feedforward Neural Network for the PM₁₀ Forecasting: Comparison with a Radial Basis Function Network and a Multivariate Linear Regression Model
2009
Caselli, M. | Trizio, L. | de Gennaro, G. | Ielpo, P.
The problem of air pollution is a frequently recurring situation and its management has social and economic considerable effects. Given the interaction of the numerous factors involved in the raising of the atmospheric pollution rates, it should be considered that the relation between the intensity of emission produced by the polluting source and the resulting pollution is not immediate. The aim of this study was to realise and to compare two support decision system (neural networks and multivariate regression model) that, correlating the air quality data with the meteorological information, are able to predict the critical pollution events. The development of a back-propagation neural network is presented to predict the daily PM₁₀ concentration 1, 2 and 3 days early. The measurements obtained by the territorial monitoring stations are one of the primary data sources; the forecasting of the major weather parameters available on the website and the forecasting of the Saharan dust obtained by the “Centro Nacional de Supercomputaciòn” website, satellite images and back trajectories analysis are used for the weather input data. The results obtained with the neural network were compared with those obtained by a multivariate linear regression model for 1 and 2 days forecasting. The relative root mean square error for both methods shows that the artificial neural networks (ANN) gives more accurate results than the multivariate linear regression model mostly for 1 day forecasting; moreover, the regression model used, in spite of ANN, failed when it had to fit spiked high values of PM₁₀ concentration.
Mostrar más [+] Menos [-]Chemical-physical and Microbiological Measurements for Indoor Air Quality Assessment at the Ca' Granda Historical Archive, Milan (Italy)
2009
Cappitelli, Francesca | Fermo, Paola | Vecchi, Roberta | Piazzalunga, Andrea | Valli, Gianluigi | Zanardini, Elisabetta | Sorlini, Claudia
In a few cases, atmospheric particulate matter characterization was taken into account together with aerobiological monitoring but never in an archive. The aim of this study was to estimate the air quality, by means of both chemical-physical and microbiological studies, at the Ca' Granda Historical Archive (Milan, Italy) that houses an important collection of documents from the 12th century. Temperature and relative humidity were measured in the rooms. Particulate matter (PM2.5) concentrations were quantified and the chemical composition, in terms of ionic components, elements, and carbonaceous fraction (total, organic, and elemental carbon) determined. The gaseous pollutants NO₂, SO₂, and O₃ and indoor acidity were also measured. Aerobiological monitoring (aerobic heterotrophic bacteria and fungi) was performed as volumes stored in the Archive were composed of organic materials, a potential energy and carbon source. In this paper, we present our findings and propose some guidelines for a better preservation of the documents.
Mostrar más [+] Menos [-]Seasonal differences in mercury accumulation in Trichiurus lepturus (Cutlassfish) in relation to length and weight in a Northeast Brazilian estuary
2009
Costa, Monica Ferreira | Barbosa, Scheyla C. T. | Barletta, Mario | Dantas, David V. | Kehrig, Helena A. | Seixas, Tércia G. | Malm, Olaf
Background, aim, and scope At tropical latitudes, and especially on the semi-arid coasts of the Brazilian Northeast, the rainfall regime governs the water quality of estuaries due to the pronounced difference between the rainy and dry seasons. These changes may be responsible for seasonal changes in bioavailability of mercury (Hg) and other pollutants to the estuarine and coastal biota. Mercury bioaccumulates along estuarine-marine food chains usually result in higher concentrations in tissues of top predators and posing a risk to both marine mammals and humans alike. The Goiana River Estuary (7.5° S) is a typical estuary of the semi-arid tropical regions and supports traditional communities with fisheries (mollusks, fish, and crustacean). It is also responsible for an important part of the biological production of the adjacent coastal waters. Materials and methods Trichiurus lepturus (Actinopterygii: Perciformes) is a pscivorous marine straggler. Fish from this species (n = 104) were captured in a trapping barrier used by the local traditional population and using an otter trawl net along the main channel of the low estuary during two dry seasons (D1 = November, December 2005, January 2006; D2 = November, December 2006, January 2007) and the end of a rainy season (R = August, September, October 2006). Fish muscle samples were preserved cold and then freeze-dried prior to analysis of its total mercury (Hg-T) contents. Total mercury was determined by cold vapor atomic absorption spectrometry (CV-AAS) with sodium borohydride as a reducing agent. Results The studied individuals (n = 104) were sub-adult (30-70 cm, 71 ind.) and adult fish (>70 cm, 33 ind.). Weight (W) (204.1 ± 97.9 g, total biomass = 21,229.7 g) and total length (TL) (63.1 ± 10.1 cm, range 29.5-89.0 cm) presented a significant (p < 0.05) correlation. Two-way ANOVA (n = 81) showed that TL and W had significant differences (p < 0.05) among seasons, being higher in D1 than in D2 and R, respectively. Moreover, season vs. month interaction were detected for the variables length and weight. For the variable weight was detected significant difference for the factor month (p < 0.05). It suggests that the fish enter the estuary at the end of the rainy season and increase in length and weight during the time they spend in the estuary. Fish from this estuary are shown to be fit for human consumption (125.3 ± 61.9 μgHg-T kg⁻¹ w.wt.; n = 104). Fish mercury contents increased with size and weight. Correlations between TL and Hg-T (r = 0.37286) and between W and Hg-T (r = 0.38212) were significant (p < 0.05). Dryer months showed higher mercury concentrations in fish (D1 773.4 ± 207.5 μgHg-T kg⁻¹ d.wt., n = 27; D2 370.1 ± 78.8 μgHg-T kg⁻¹ d.wt., n = 27; R 331.2 ± 138.5 μgHg-T kg⁻¹ d.wt., n = 27). The variable mercury concentration showed differences in relation to the factor season (p < 0.05), where fish captured during the first dry season showed the highest concentration of mercury. The correlation between Hg-T and rainfall (Rf) showed a negative correlation (r = -0.56; p < 0.05). Discussion The main likely source of mercury to this estuary is diffuse continental run off, including urban and industrial effluents. Since concentration of mercury in fish tissue is negatively correlated to rainfall, but positively correlated with fish length and weight, it suggests that fish growth in this estuary results in mercury uptake and concentration on the fish tissue. In the dry season of 2005-2006, when rainfall remained below the historic average, fish bioaccumulated significantly more mercury than in the dry season 2006-2007, when rainfall was within the predictable historic average. It is suggested that less rainfall, and consequently less particulate matter and less primary production in the estuary, make mercury more available to the higher levels of the estuarine food chain. In the case of higher rainfall, when river flow increases and water quality in the estuary is reduced, mercury probably is quickly exported associated to the particulate matter to the adjacent coastal waters where it then disperses. This species is a potential routine bioindicator for mercury contamination of the biota, but so far was used only with a limited number of individuals and contexts. Conclusions Fish from the Goiana River estuary can still be safely consumed by the local population. However, any further contamination of this resource might lead to total mercury levels above the recommended limits for pregnant women and small children. The proposed heavy dependency of total mercury levels in fish on water quality indicates that land use and water quality standards must be more closely watched in order to guarantee that best possible practices are in place to prevent bioaccumulation of mercury and its transfer along the food chain. Human interventions and climatic events which affect river water flow are also playing a role in the mercury cycle at tropical semi-arid estuaries. Recommendations and perspectives T. lepturus is largely consumed by coastal populations of tropical and sub-tropical countries all over the world. It is also consumed by a number of marine mammals over which we have a strong conservation interest. This species is also a link among different ecosystems along the estuarine ecocline. Therefore, knowledge of its degree of contamination might contribute to public health issues as well as marine conservation actions. Studies on mercury and other contaminants using this species as bioindicator (cosmopolitan, readily available) could help elucidating mechanisms through which pollutants are being transferred not only through the food chain, but also from estuarine-coastal-open waters. In addition, using the same species in marine pollution studies, especially as part of a mosaic of species, allows for wide range comparisons of marine food chain contamination.
Mostrar más [+] Menos [-]A field survey--Staroe lake suffering from atmospheric deposition in the region north of the Arctic Circle
2009
Kikuchi, Ryunosuke | Gorbacheva, Tamara T
Background, aim, and scope The Arctic holds large stores of minerals, and extracted materials are provided to the world's economy; in this sense, the Arctic issue associated with mining is not local but global. In a part of the Arctic region (the Kola Peninsula, 66-70° N and 28-41° E), metal levels are generally elevated in the lake sediment. There is a question as to what results in elevated metal levels--a natural process (naturally abundant minerals) or an anthropogenic process (mining and metallurgy). In terms of solving this question, Staroe lake located on the Kola Peninsula was researched as a case study. Materials and methods The following parameters were determined in relation with Staroe lake: (1) the current quality of the lake's water--each 1,000-ml sample was collected at a surface point and a deep point (near the bottom layer), and the collected samples were directly analyzed after filtration; (2) atmospheric bulk deposition--bulk deposition was collected using a set of three rainwater samplers near the lake. In addition, bulk deposition was collected in a background site (250 km to the southwest of the smelter complex) as a reference; and (3) sediment profile (plus principal component analysis)--lake-bottom sediment was collected by an open-gravimetric column sampler equipped with an automatic diaphragm. After collection, the sample columns were cut at a 1-cm interval for analysis. Eigenvalues and variances by factor were calculated from the correlation coefficients. Results The obtained data show that (1) naturally poor elements (Cu, Ni, Si, and SO₄ ²⁻) dominantly influence the lake's water quality; (2) they are transported from the anthropogenic sources to the study lake through the atmospheric pathway; (3) mainly the contents of Cu, Ni, Sr, and Ca have influenced the sediment quality since the 1950s, corresponding to the industrial movement; and (4) Cu, Ni, and Sr originate from an anthropogenic source (smelter), and Ca originates from both natural and anthropogenic sources. Discussion As compared with the Russian standard (San Pin 2.1.980-00), the contents of NO₃ ⁻ (50.3 ± 0.1 mg l⁻¹) and particulates (2.3 ± 0.2 mg l⁻¹) exceeded the standard levels (0.7 mg l⁻¹ NO₃ ⁻ and 45 mg l⁻¹ particulates); Staroe lake may be slightly contaminated. However, the contamination factor (comparison with the background data) implies that Staroe lake is considerably contaminated. There is a strong possibility that fine overburden detritus (<0.1 mm diameter) may be transported from an open pit to the study lake by natural forces such as wind. Although it is difficult to suppose that one factor dominantly affects the sediment quality, it follows from a factor analysis that factors 1 and 2 account for about 70% of the total variance: Factor 1 is the most dominant, and factor 2 is the second most dominant in the variability of sediment quality. It is considered that Cu, Sr, and Ni in factor 1 originate from anthropogenic sources because they are poor in sediment rocks. Conclusions The field survey conducted in Staroe lake can give the following answers to the key objectives: (1) The present water quality is affected by Cu, Ni, Si, and SO₄ ²⁻ in light of the contamination factor, and these elements originate from anthropogenic sources (the smelter and the open pit) and are transported to the lake through the atmospheric pathway; (2) the sediment profile and statistic analysis show that the lake quality has been influenced by deposition of metals since the 1950s; and (3) Cu, Ni, Sr, and Ca have influenced the sediment quality in light of the most dominant factor--Cu, Ni, and Sr originate from an anthropogenic source, whereas Ca comes from both natural and anthropogenic sources. Recommendations and perspectives The presented lake survey shows that the dispersion of human-related pollutants via the atmospheric pathway takes place in the Arctic region. If the current pollution continues without countermeasures, the high-latitude environment may lose its original characteristics; hence, this subject is important when considering how to implement a wide range of environmental protection measures in the Arctic.
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