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3-Way pattern-recognition of PAHs from Galicia (NW Spain) seawater samples after the Prestige's wreck 全文
2010
Grueiro-Noche, G. | Andrade, J.M. | Muniategui-Lorenzo, S. | López-Mahía, P. | Prada-Rodríguez, D.
In November 2002 the oil tanker ‘Prestige’ released 65 000 tons of a heavy fuel oil throughout the Galician coastline (NW Spain), causing extensive damage to marine life, natural resources and economic activities at Northern Portugal, Spain and SW France. To evaluate the impact of the oil spill on the aquatic system, 30 polycyclic aromatic hydrocarbons (PAHs), including alkylated derivatives, were analyzed in seawater on five different sampling campaigns from 2002 to 2004. Sampling was made along the Galician continental shelf. In each station three samples were collected at three different depths (surface, mid-depth and bottom). Four different approaches for 3-way analyses (Catenated-PCA, Matrix-Augmented Principal Components Analysis, Parallel Factor Analysis and Procrustes rotation) have been used to asses the major sources of PAHs into the seawater. They revealed two main pollution patterns: one related to oil spillages and discharge of petroleum products, and another more associated with a diffuse anthropogenic origin. Oil- and anthropogenic-related sources of PAHs were found in a survey program in Galicia after the Prestige wreck, the latter being more relevant as time went by.
显示更多 [+] 显示较少 [-]Arsenic accumulation and phosphorus status in two rice (Oryza sativa L.) cultivars surveyed from fields in South China 全文
2010
Lü, Ying | Dong, Fei | Deacon, Claire | Chen, Huo-jun | Raab, Andrea | Meharg, Andrew A.
The consumption of paddy rice (Oryza sativa L.) is a major inorganic arsenic exposure pathway in S.E. Asia. A multi-location survey was undertaken in Guangdong Province, South China to assess arsenic accumulation and speciation in 2 rice cultivars, one an Indica and the other a hybrid Indica. The results showed that arsenic concentrations in rice tissue increased in the order grain < husk < straw < root. Rice grain arsenic content of 2 rice cultivars was significant different and correlated with phosphorus concentration and molar ratio of P/As in shoot, being higher for the Indica cultivar than for the hybrid Indica, which suggests altering shoot phosphorus status as a promising route for breeding rice cultivars with reduced grain arsenic. Speciation of grain arsenic, performed using HPLC-ICP-MS, identified inorganic arsenic as the dominant arsenic species present in the rice grain.
显示更多 [+] 显示较少 [-]Immobilization of non-point phosphorus using stabilized magnetite nanoparticles with enhanced transportability and reactivity in soils 全文
2010
Pan, Gang | Li, Lei | Zhao, Dongye | Chen, Hao
Laboratory batch and column experiments were conducted to investigate the immobilization of phosphorus (P) in soils using synthetic magnetite nanoparticles stabilized with sodium carboxymethyl cellulose (CMC-NP). Although CMC-stabilized magnetite particles were at the nanoscale, phosphorus removal by the nanoparticles was less than that of microparticles (MP) without the stabilizer due to the reduced P reactivity caused by the coating. The P reactivity of CMC-NP was effectively recovered when cellulase was added to degrade the coating. For subsurface non-point P pollution control for a water pond, it is possible to inject CMC-NP to form an enclosed protection wall in the surrounding soils. Non-stabilized “nanomagnetite” could not pass through the soil column under gravity because it quickly agglomerated into microparticles. The immobilized P was 30% in the control soil column, 33% when treated by non-stabilized MP, 45% when treated by CMC-NP, and 73% when treated by both CMC-NP and cellulase. CMC-stabilized magnetite nanoparticles can effectively penetrate soil columns and immobilize phosphate in situ.
显示更多 [+] 显示较少 [-]Evaluating the cytotoxicity of palladium/magnetite nano-catalysts intended for wastewater treatment 全文
2010
Hildebrand, Heike | Kühnel, Dana | Potthoff, Annegret | Mackenzie, Katrin | Springer, Armin | Schirmer, Kristin
Palladium/magnetite nanoparticulate catalysts were developed for efficient elimination of halogenated organic pollutants from contaminated wastewater. Particle recovery from treated water can be ensured via magnetic separation. However, in worst-case scenarios, this catalyst removal step might fail, leading to particle release into the environment. Therefore, a toxicological study was conducted to investigate the impact of both pure magnetite and palladium/magnetite nanoparticle exposure upon human skin (HaCaT) and human colon (CaCo-2) cell lines and a cell line from rainbow trout gills (RTgill-W1). To quantify cell viability after particle exposure, three endpoints were examined for all tested cell lines. Additionally, the formation of reactive oxygen species was studied for the human cells. The results showed only minor effects of the particles on the tested cell systems and support the assumption that palladium/magnetite nano-catalysts can be implemented for a new wastewater treatment technology in which advantageous catalyst properties outweigh the risks. Impact of nano-Pd/magnetite on cell viability was studied and appears to be low.
显示更多 [+] 显示较少 [-]Mercury in urban soils with various types of land use in Beijing, China 全文
2010
Chen, Xi | Xia, Xinghui | Wu, Shan | Wang, Fan | Guo, Xuejun
Mercury (Hg) concentration was investigated for 127 urban soil samples collected from business area (BA), classical garden (CG), culture and education area (CEA), public green space (PGS), residential area (RA) and roadside area (RSA) in Beijing. The median of Hg concentration in Beijing was 0.26 mg/kg. The value in CG was much higher than the other 5 types of land use, which was due to the historical use of Hg. More than 87% of the samples were not contaminated according to the guideline values of China, UK, Canada, and USEPA. Spatial distribution map revealed that Hg concentration showed a decreasing trend from the center to the suburb, it increased with the age of the urban area. Hg contamination in urban area of Beijing is marked by features of non-point sources associated with human activities, and it is most likely to be the common characteristics of Hg contamination in cities. Hg distribution in Beijing was affected by both types of land use and the age of urban area.
显示更多 [+] 显示较少 [-]Phytotoxicity of atrazine, isoproturon, and diuron to submersed macrophytes in outdoor mesocosms 全文
2010
Knauert, Stefanie | Singer, Heinz | Hollender, Juliane | Knauer, Katja
The submersed macrophytes Elodea canadensis, Myriophyllum spicatum and Potamogeton lucens were constantly exposed over a five-week period to environmentally relevant concentrations of atrazine, isoproturon, diuron, and their mixture in outdoor mesocosms. Effects were evaluated investigating photosynthetic efficiency (PE) of the three macrophytes and growth of M. spicatum and E. canadensis. Adverse effects on PE were observed on days 2 and 5 after application. M. spicatum was found to be the more sensitive macrophyte. E. canadensis and P. lucens were less sensitive to atrazine, diuron and the mixture and insensitive to isoproturon. PE of M. spicatum was similarly affected by the single herbicides and the mixture demonstrating concentration addition. Growth of E. canadensis and M. spicatum was not reduced indicating that herbicide exposure did not impair plant development. Although PE measurements turned out to be a sensitive method to monitor PSII herbicides, plant growth remains the more relevant ecological endpoint in risk assessment. Short-term effects on photosynthesis did not result in growth reduction of submerse macrophytes exposed to PSII inhibitors.
显示更多 [+] 显示较少 [-]Historical record of polycyclic aromatic hydrocarbons (PAHs) and spheroidal carbonaceous particles (SCPs) in marine sediment cores from Admiralty Bay, King George Island, Antarctica 全文
2010
Martins, César C. | Bícego, Márcia C. | Rose, N. L. (Neil L) | Taniguchi, Satie | Lourenço, Rafael A. | Figueira, Rubens C.L. | Mahiques, Michel M. | Montone, Rosalinda C.
This paper describes the first results of polycyclic aromatic hydrocarbons (PAHs) and spheroidal carbonaceous particles (SCPs) in sediment cores of Admiralty Bay, Antarctica. These markers were used to assess the local input of anthropogenic materials (particulate and organic compounds) as a result of the influence of human occupation in a sub-Antarctic region and a possible long-range atmospheric transport of combustion products from sources in South America. The highest SCPs and PAHs concentrations were observed during the last 30 years, when three research stations were built in the area and industrial activities in South America increased. The concentrations of SCPs and PAHs were much lower than those of other regions in the northern hemisphere and other reported data for the southern hemisphere. The PAH isomer ratios showed that the major sources of PAHs are fossil fuels/petroleum, biomass combustion and sewage contribution generally close to the Brazilian scientific station. SCPs and PAHs indicate the increase in human activities in a sub-Antarctic region.
显示更多 [+] 显示较少 [-]Air pollution
2010
Tiwary, Abhishek | Colls, Jeremy
This book on air pollution science includes information on the role of air pollutants in climate change and looks at the developing economies around the world where air pollution problems are on the rise. Other topics include - gaseous and particulate air pollutants, measurement techniques, meteorology and dispersion modelling, mobile sources, indoor air, effects on plants, materials, humans and animals. It also looks at air pollution mitigation by vegetation, mainly its role in maintaining a sustainable urban environment.
显示更多 [+] 显示较少 [-]The chemistry and behaviour of antimony in the soil environment with comparisons to arsenic: A critical review 全文
2010
Wilson, Susan C. | Lockwood, Peter V. | Ashley, Paul M. | Tighe, Matthew
This article provides a critical review of the environmental chemistry of inorganic antimony (Sb) in soils, comparing and contrasting findings with those of arsenic (As). Characteristics of the Sb soil system are reviewed, with an emphasis on speciation, sorption and phase associations, identifying differences between Sb and As behaviour. Knowledge gaps in environmentally relevant Sb data for soils are identified and discussed in terms of the limitations this imposes on understanding the fate, behaviour and risks associated with Sb in environmental soil systems, with particular reference to mobility and bioavailability.
显示更多 [+] 显示较少 [-]Rapid detection of toxic metals in non-crushed oyster shells by portable X-ray fluorescence spectrometry 全文
2010
Chou, Ju | Clement, Garret | Bursavich, Bradley | Elbers, Don | Cao, Baobao | Zhou, Weilie
The aim of this study was the multi-elemental detection of toxic metals such as lead (Pb) in non-crushed oyster shells by using a portable X-ray fluorescence (XRF) spectrometer. A rapid, simultaneous multi-element analytical methodology for non-crushed oyster shells has been developed using a portable XRF which provides a quick, quantitative, non-destructive, and cost-effective mean for assessment of oyster shell contamination from Pb. Pb contamination in oyster shells was further confirmed by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The results indicated that Pb is distributed in-homogeneously in contaminated shells. Oyster shells have a lamellar structure that could contribute to the high accumulation of Pb on oyster shells.
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