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Levels and distribution of organophosphorus flame retardants and plasticizers in fishes from Manila Bay, the Philippines Texto completo
2011
Kim, Joon-Woo | Isobe, Tomohiko | Chang, Kwang-Hyeon | Amano, Atsuko | Maneja, Rommel H. | Zamora, Peter B. | Siringan, Fernando P. | Tanabe, Shinsuke
Organophosphorus compounds (OPCs) and stable isotope ratios (δ¹³C and δ¹⁵N) were determined in 58 fishes belonging to 20 species collected from Manila Bay, the Philippines. OPCs were detected in most of the samples and found up to μg/g lw (lipid weight) level, suggesting their ubiquitous presence in the coastal marine environment of the Philippines. Higher levels (>1000 ng/g lw) of total OPCs were determined in yellowstriped goatfish, silver sillago, tripletail wrasse and bumpnose trevally indicates either their active uptake from ambient water or lower metabolic capacity of these species. Levels of triphenyl phosphate (TPhP) in demersal species showed a positive correlation with δ¹⁵N, indicating that TPhP was adsorbed onto the particle, settled down to the bottom sediment and accumulated through the benthic food web rather than the pelagic. Estimated dietary intake of OPCs in Manila Bay fishes were four to five orders of magnitude lower than the proposed reference dose (RfD).
Mostrar más [+] Menos [-]Aggregation and ecotoxicity of CeO₂ nanoparticles in synthetic and natural waters with variable pH, organic matter concentration and ionic strength Texto completo
2011
Van Hoecke, Karen | De Schamphelaere, Karel A.C. | Van der Meeren, Paul | Smagghe, Guy | Janssen, Colin R.
The influence of pH (6.0–9.0), natural organic matter (NOM) (0–10 mg C/L) and ionic strength (IS) (1.7–40 mM) on 14 nm CeO₂ NP aggregation and ecotoxicity towards the alga Pseudokirchneriella subcapitata was assessed following a central composite design. Mean NP aggregate sizes ranged between 200 and 10000 nm. Increasing pH and IS enhanced aggregation, while increasing NOM decreased mean aggregate sizes. The 48 h-EᵣC20s ranged between 4.7 and 395.8 mg CeO₂/L. An equation for predicting the 48 h-EᵣC20 (48 h-EᵣC20 = −1626.4 × (pH) + 109.45 × (pH)² + 116.49 × ([NOM]) − 14.317 × (pH) × ([NOM]) + 6007.2) was developed. In a validation study with natural waters the predicted 48 h-EᵣC20 was a factor 1.08–2.57 lower compared to the experimental values.
Mostrar más [+] Menos [-]On airborne nano/micro-sized wear particles released from low-metallic automotive brakes Texto completo
2011
Kukutschová, Jana | Moravec, Pavel | Tomášek, Vladimír | Matějka, Vlastimil | Smolík, Jiří | Schwarz, Jaroslav | Seidlerová, Jana | Šafářová, Klára | Filip, Peter
The paper addresses the wear particles released from commercially available “low-metallic” automotive brake pads subjected to brake dynamometer tests. Particle size distribution was measured in situ and the generated particles were collected. The collected fractions and the original bulk material were analyzed using several chemical and microscopic techniques. The experiments demonstrated that airborne wear particles with sizes between 10nm and 20μm were released into the air. The numbers of nanoparticles (<100nm) were by three orders of magnitude larger when compared to the microparticles. A significant release of nanoparticles was measured when the average temperature of the rotor reached 300°C, the combustion initiation temperature of organics present in brakes. In contrast to particle size distribution data, the microscopic analysis revealed the presence of nanoparticles, mostly in the form of agglomerates, in all captured fractions. The majority of elements present in the bulk material were also detected in the ultra-fine fraction of the wear particles.
Mostrar más [+] Menos [-]Effects of nitrogen deposition and soil fertility on cover and physiology of Cladonia foliacea (Huds.) Willd., a lichen of biological soil crusts from Mediterranean Spain Texto completo
2011
Ochoa-Hueso, Raúl | Manrique, Esteban
Effects of nitrogen deposition and soil fertility on cover and physiology of Cladonia foliacea (Huds.) Willd., a lichen of biological soil crusts from Mediterranean Spain Texto completo
2011
Ochoa-Hueso, Raúl | Manrique, Esteban
We are fertilizing a thicket with 0, 10, 20 and 50kg nitrogen (N) ha⁻¹ yr⁻¹ in central Spain. Here we report changes in cover, pigments, pigment ratios and FvFm of the N-tolerant, terricolous, lichen Cladonia foliacea after 1–2 y adding N in order to study its potential as biomarker of atmospheric pollution. Cover tended to increase. Pigments increased with fertilization independently of the dose supplied but only significantly with soil nitrate as covariate. β-carotene/chlorophylls increased with 20–50kgNha⁻¹yr⁻¹ (over the background) and neoxanthin/chlorophylls also increased with N. (Neoxanthin+lutein)/carotene decreased with N when nitrate and pH seasonalities were used as covariates. FvFm showed a critical load above 40kgNha⁻¹yr⁻¹. Water-stress, iron and copper also explained variables of lichen physiology. We conclude that this tolerant lichen could be used as biomarker and that responses to N are complex in heterogeneous Mediterranean-type landscapes.
Mostrar más [+] Menos [-]Effects of nitrogen deposition and soil fertility on cover and physiology of Cladonia foliacea (Huds.) Willd., a lichen of biological soil crusts from Mediterranean Spain Texto completo
2011
Ochoa Hueso, Raúl | Manrique, Esteban | Biología
Estamos fertilizando un matorral con 0, 10, 20 y 50 kg de nitrógeno (N) ha−1 año−1 en el centro de España. Aquí informamos cambios en la cobertura, los pigmentos, las proporciones de pigmentos y FvFm del liquen terrícola Cladonia foliacea, tolerante al N, después de 1 a 2 años de agregar N para estudiar su potencial como biomarcador de la contaminación atmosférica. La cobertura tendió a aumentar. Los pigmentos aumentaron con la fertilización independientemente de la dosis suministrada, pero sólo significativamente con el nitrato del suelo como covariable. Las β-caroteno/clorofilas aumentaron con 20–50 kg N ha-1 año-1 (en comparación con el fondo) y las neoxantina/clorofilas también aumentaron con N. (Neoxantina+luteína)/caroteno disminuyó con N cuando se utilizaron los valores estacionales de nitrato y pH como covariables. FvFm mostró una carga crítica superior a 40 kg N ha-1 año-1. El estrés hídrico, el hierro y el cobre también explicaron variables de la fisiología del liquen. Concluimos que este liquen tolerante podría usarse como biomarcador y que las respuestas al N son complejas en paisajes heterogéneos de tipo mediterráneo.
Mostrar más [+] Menos [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach Texto completo
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach Texto completo
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study. The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices) integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment.
Mostrar más [+] Menos [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach. | Evaluation de la qualité des eaux souterraines d'une friche industrielle belge suivant la méthodologie TRIAD. Texto completo
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study.The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices)integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment. | Science of Sustainable Development (FRAC-WECO project, 2007-2010).
Mostrar más [+] Menos [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach. | Evaluation de la qualité des eaux souterraines d'une friche industrielle belge suivant la méthodologie TRIAD. Texto completo
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
peer reviewed | Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study. The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices)integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment. | Science of Sustainable Development (FRAC-WECO project, 2007-2010).
Mostrar más [+] Menos [-]Bioremediation of benzene-, MTBE- and ammonia-contaminated groundwater with pilot-scale constructed wetlands Texto completo
2011
Seeger, Eva M. | Kuschk, Peter | Fazekas, Helga | Grathwohl, Peter | Kaestner, Matthias
In this pilot-scale constructed wetland (CW) study for treating groundwater contaminated with benzene, MTBE, and ammonia-N, the performance of two types of CWs (a wetland with gravel matrix and a plant root mat) was investigated. Hypothesized stimulative effects of filter material additives (charcoal, iron(III)) on pollutant removal were also tested. Increased contaminant loss was found during summer; the best treatment performance was achieved by the plant root mat. Concentration decrease in the planted gravel filter/plant root mat, respectively, amounted to 81/99% for benzene, 17/82% for MTBE, and 54/41% for ammonia-N at calculated inflow loads of 525/603 mg/m²/d, 97/112 mg/m²/d, and 1167/1342 mg/m²/d for benzene, MTBE, and ammonia-N. Filter additives did not improve contaminant depletion, although sorption processes were observed and elevated iron(II) formation indicated iron reduction. Bacterial and stable isotope analysis provided evidence for microbial benzene degradation in the CW, emphasizing the promising potential of this treatment technique.
Mostrar más [+] Menos [-]Recalcitrance of polycyclic aromatic hydrocarbons in soil contributes to background pollution Texto completo
2011
Posada-Baquero, Rosa | Ortega-Calvo, Jose Julio
Recalcitrance of polycyclic aromatic hydrocarbons in soil contributes to background pollution Texto completo
2011
Posada-Baquero, Rosa | Ortega-Calvo, Jose Julio
The microbial accessibility of native phenanthrene and pyrene was determined in soils representing background scenarios for pollution by polycyclic aromatic hydrocarbons (PAHs). The soils were selected to cover a wide range of concentrations of organic matter (1.7–10.0%) and total PAHs (85–952μg/kg). The experiments included radiorespirometry determinations of biodegradation with ¹⁴C-labeled phenanthrene and pyrene and chemical analyses to determine the residual concentrations of the native compounds. Part of the tests relied on the spontaneous biodegradation of the chemicals by native microorganisms; another part also involved inoculation with PAH-degrading bacteria. The results showed the recalcitrance of PAHs already present in the soils. Even after extensive mineralization of the added ¹⁴C-PAHs, the concentrations of native phenanthrene and pyrene did not significantly decrease. We suggest that aging processes operating at background concentrations may contribute to recalcitrance and, therefore, to ubiquitous pollution by PAHs in soils.
Mostrar más [+] Menos [-]Recalcitrance of polycyclic aromatic hydrocarbons in soil contributes to background pollution Texto completo
2011
Posada Baquero, Rosa | Ortega Calvo, J. J. | Junta de Andalucía | Ministerio de Ciencia e Innovación (España)
The microbial accessibility of native phenanthrene and pyrene was determined in soils representing background scenarios for pollution by polycyclic aromatic hydrocarbons (PAHs). The soils were selected to cover a wide range of concentrations of organic matter (1.7-10.0%) and total PAHs (85-952 μg/kg). The experiments included radiorespirometry determinations of biodegradation with 14C-labeled phenanthrene and pyrene and chemical analyses to determine the residual concentrations of the native compounds. Part of the tests relied on the spontaneous biodegradation of the chemicals by native microorganisms; another part also involved inoculation with PAH-degrading bacteria. The results showed the recalcitrance of PAHs already present in the soils. Even after extensive mineralization of the added 14C-PAHs, the concentrations of native phenanthrene and pyrene did not significantly decrease. We suggest that aging processes operating at background concentrations may contribute to recalcitrance and, therefore, to ubiquitous pollution by PAHs in soils. | Support for this research was provided by the Spanish Junta de Andalucía (projects “Diagnóstico de la Situación Ambiental del Campo de Gibraltar” and PAI RNM 312), and the Spanish Ministry of Science and Innovation (CGL2007-64199 and CGL2010-22068-C02-01). | Peer Reviewed
Mostrar más [+] Menos [-]Influence of extracellular polymeric substances (EPS) on Cd adsorption by bacteria Texto completo
2011
Wei, Xing | Fang, Linchuan | Cai, Peng | Huang, Qiaoyun | Chen, Hao | Liang, Wei | Rong, Xinming
The role of extracellular polymeric substances (EPS) in Cd adsorption by Bacillus subtilis and Pseudomonas putida was investigated using a combination of batch adsorption experiments, potentiometric titrations, Fourier transform infrared spectroscopy (FTIR). An increased adsorption capacity of Cd was observed for untreated bacteria relative to that for EPS-free bacteria. Surface complexation modeling of titration data showed the similar pKₐ values of functional groups (carboxyl, phosphate and hydroxyl) between untreated and EPS-free bacteria. However, site concentrations on the untreated bacteria were found to be higher than those on the EPS-free bacteria. FTIR spectra also showed that no significant difference in peak positions was observed between untreated and EPS-free bacteria and carboxyl and phosphate groups were responsible for Cd adsorption on bacterial cells. The information obtained in this study is of fundamental significance for understanding the interaction mechanisms between heavy metals and biofilms in natural environments.
Mostrar más [+] Menos [-]Spatiotemporal dynamics of spring and stream water chemistry in a high-mountain area Texto completo
2011
Żelazny, Mirosław | Astel, Aleksander | Wolanin, Anna | Małek, Stanisław
Spatiotemporal dynamics of spring and stream water chemistry in a high-mountain area Texto completo
2011
Żelazny, Mirosław | Astel, Aleksander | Wolanin, Anna | Małek, Stanisław
The present study deals with the application of the self-organizing map (SOM) technique in the exploration of spatiotemporal dynamics of spring and stream water samples collected in the Chochołowski Stream Basin located in the Tatra Mountains (Poland). The SOM-based classification helped to uncover relationships between physical and chemical parameters of water samples and factors determining the quality of water in the studied high-mountain area. In the upper part of the Chochołowski Stream Basin, located on the top of the crystalline core of the Tatras, concentrations of the majority of ionic substances were the lowest due to limited leaching. Significantly higher concentration of ionic substances was detected in spring and stream samples draining sedimentary rocks. The influence of karst-type springs on the quality of stream water was also demonstrated.
Mostrar más [+] Menos [-]Spatiotemporal dynamics of spring and stream water chemistry in a high-mountain area Texto completo
Żelazny Mirosław | Aleksander Astel | Anna Wolanin | Stanisław Małek
The present study deals with the application of the self-organizing map (SOM) technique in the exploration of spatiotemporal dynamics of spring and stream water samples collected in the Chochołowski Stream Basin located in the Tatra Mountains (Poland). The SOM-based classification helped to uncover relationships between physical and chemical parameters of water samples and factors determining the quality of water in the studied high-mountain area. In the upper part of the Chochołowski Stream Basin, located on the top of the crystalline core of the Tatras, concentrations of the majority of ionic substances were the lowest due to limited leaching. Significantly higher concentration of ionic substances was detected in spring and stream samples draining sedimentary rocks. The influence of karst-type springs on the quality of stream water was also demonstrated. | Tatra Mountains Basin Water chemical profile Unsupervised classification Self-organizing maps Rock Spruce stands | 40 | 1048-1057 | 159
Mostrar más [+] Menos [-]Spatial and seasonal variations of polycyclic aromatic hydrocarbons in Haihe Plain, China Texto completo
2011
Wang, Rong | Cao, Hongying | Li, Wei | Wang, Wei | Wang, Wentao | Zhang, Liwen | Liu, Jiumeng | Ouyang, Huiling | Tao, Shu
A dynamic fugacity model was developed to simulate the spatial and seasonal variations of PAHs in Haihe Plain, China. The calculated and measured concentrations exhibited good consistency in magnitude with deviations within a factor of 4 in air and 2 in soil. The spatial distributions of PAHs in air were mainly controlled by emission while the seasonal variations were dominated by emission and gas–particle partition. In soil, the spatial distributions of PAHs were controlled by the soil organic carbon content while the seasonal variations were insignificant. The severest soil contamination was observed in Shanxi and followed by the southwest of Hebei province. Transfer fluxes of total PAHs between air and soil were calculated. The spatial distribution of air-to-soil flux was closely related to the landcover while the soil-to-air flux changed with soil organic matter content. Monte Carlo simulation was done to evaluate the uncertainty of the estimated results in air.
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