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Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments Full text
2013
Baena-Nogueras, Rosa María | González-Mazo, Eduardo | Lara-Martín, Pablo A.
Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments Full text
2013
Baena-Nogueras, Rosa María | González-Mazo, Eduardo | Lara-Martín, Pablo A.
A new methodology has been developed for the determination of secondary alkane sulfonates (SAS), an anionic surfactant, in environmental matrices. Sediment and sludge samples were extracted using pressurized liquid extraction and sonication, whereas wastewater and surface water samples were processed using solid-phase extraction. Extraction recoveries were acceptable for both aqueous (78–120%) and solid samples (83–100%). Determination of SAS was carried out by high or ultra performance liquid chromatography – mass spectrometry using ion trap and time-of-flight detectors. The methodology was applied to samples from Guadalete River (SW Spain), where SAS concentrations below 1 μg L−1 were measured in surface water, and from 72 to 9737 μg kg−1 in sediments. Differential partitioning was observed for SAS homologues as those having a longer hydrocarbon chain which preferentially sorbed onto particulate matter. A preliminary environmental risk assessment also showed that SAS measured levels were not harmful to the aquatic community in the sampling area.
Show more [+] Less [-]Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments Full text
Baena Nogueras, Rosa María | González Mazo, Eduardo | Lara Martín, Pablo Antonio | Química Física
A new methodology has been developed for the determination of secondary alkane sulfonates (SAS), an anionic surfactant, in environmental matrices. Sediment and sludge samples were extracted using pressurized liquid extraction and sonication, whereas wastewater and surface water samples were processed using solid-phase extraction. Extraction recoveries were acceptable for both aqueous (78-120%) and solid samples (83-100%). Determination of SAS was carried out by high or ultra performance liquid chromatography e mass spectrometry using ion trap and time-of-flight detectors. The methodology was applied to samples from Guadalete River (SW Spain), where SAS concentrations below 1 mg L 1 were measured in surface water, and from 72 to 9737 mg kg 1 in sediments. Differential partitioning was observed for SAS homologues as those having a longer hydrocarbon chain which preferentially sorbed onto particulate matter. A preliminary environmental risk assessment also showed that SAS measured levels were not harmful to the aquatic community in the sampling area.
Show more [+] Less [-]Upward and downward solar-induced chlorophyll fluorescence yield indices of four tree species as indicators of traffic pollution in Valencia Full text
2013
Van Wittenberghe, Shari | Alonso, Luis | Verrelst, Jochem | Hermans, Inge | Delegido, Jesús | Veroustraete, Frank | Valcke, Roland | Moreno, José | Samson, Roeland
Passive steady-state chlorophyll fluorescence (Fs) provides a direct diagnosis of the functional status of vegetation photosynthesis. With the prospect of mapping Fs using remote sensing techniques, field measurements are mandatory to understand to which extent Fs allows detecting plant stress in different environments. Trees of four common species in Valencia were classified in either a low or a high local traffic exposure class based on their leaf magnetic value. Upward and downward hyperspectral fluorescence yield (FY) and indices based on the two Fs peaks (at 687 and 741 nm) were calculated. FY indices of P. canariensis and P. x acerifolia were significantly different between the two traffic exposure classes defined, but not for C. australis nor M. alba. While chlorophyll content could not indicate the difference between low and high traffic exposure, the FY(687)/FY(741) peak ratio increased significantly (p < 0.05) for both leaf sides for the higher traffic exposure class.
Show more [+] Less [-]Improving estimates of air pollution exposure through ubiquitous sensing technologies Full text
2013
de Nazelle, Audrey | Seto, Edmund | Donaire-Gonzalez, David | Mendez, Michelle | Matamala Blanch, Jaime | Nieuwenhuijsen, Mark J. | Jerrett, Michael
Traditional methods of exposure assessment in epidemiological studies often fail to integrate important information on activity patterns, which may lead to bias, loss of statistical power, or both in health effects estimates. Novel sensing technologies integrated with mobile phones offer potential to reduce exposure measurement error. We sought to demonstrate the usability and relevance of the CalFit smartphone technology to track person-level time, geographic location, and physical activity patterns for improved air pollution exposure assessment. We deployed CalFit-equipped smartphones in a free-living population of 36 subjects in Barcelona, Spain. Information obtained on physical activity and geographic location was linked to space-time air pollution mapping. We found that information from CalFit could substantially alter exposure estimates. For instance, on average travel activities accounted for 6% of people's time and 24% of their daily inhaled NO2. Due to the large number of mobile phone users, this technology potentially provides an unobtrusive means of enhancing epidemiologic exposure data at low cost.
Show more [+] Less [-]Nature and sources of particle associated polycyclic aromatic hydrocarbons (PAH) in the atmospheric environment of an urban area Full text
2013
Callén, M.S. | López, J.M. | Iturmendi, A. | Mastral, A.M.
The total PAH associated to the airborne particulate matter (PM10) was apportioned by one receptor model based on positive matrix factorization (PMF) in an urban environment (Zaragoza city, Spain) during February 2010–January 2011. Four sources associated with coal combustion, gasoline, vehicular and stationary emissions were identified, allowing a good modelling of the total PAH (R2 = 0.99). A seasonal behaviour of the four factors was obtained with higher concentrations in the cold season. The NE direction was one of the predominant directions showing the negative impact of industrial parks, a paper factory and a highway located in that direction. Samples were classified according to hierarchical cluster analysis obtaining that, episodes with the most negative impact on human health (the highest lifetime cancer risk concentrations), were produced by a higher contribution of stationary and vehicular emissions in winter season favoured by high relative humidity, low temperature and low wind speed.
Show more [+] Less [-]Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activity Full text
2013
Sureda, Antoni | Natalotto, Antonino | Álvarez, Elvira | Deudero, Salud
Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activity Full text
2013
Sureda, Antoni | Natalotto, Antonino | Álvarez, Elvira | Deudero, Salud
Environmental pollutants exert immunotoxical effects on aquatic organisms. The aim was to determine the antioxidant response, markers of oxidative damage and reactive oxygen species production in hemocytes of Pinna nobilis, the largest endemic bivalve in the Mediterranean Sea, under anthropogenic pressure. P. nobilis individuals were collected from two locations along Mallorca Island waters attending to different degree of human impact and the hemocytes were obtained. Specimens from the impacted area showed increased activities of the antioxidant enzymes – catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase –, myeloperoxidase activity and reduced glutathione levels. No differences in oxidative damage markers – malondiahdehyde and carbonyl index – were evidenced between the pristine and polluted areas. Hemocytes from the polluted area presented increased capability to generate reactive oxygen species and nitrite/nitrate when activated. In conclusion, the human activities primed hemocytes for oxidative burst and increased the antioxidant mechanism without evidence of oxidative damage.
Show more [+] Less [-]Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activiy Full text
2013
Sureda, Antoni | Natalotto, Antonino | Álvarez, Elvira | Deudero, Salud
Environmental pollutants exert immunotoxical effects on aquatic organisms. The aim was to determine the antioxidant response, markers of oxidative damage and reactive oxygen species production in hemocytes of Pinna nobilis, the largest endemic bivalve in the Mediterranean Sea, under anthropogenic pressure. P. nobilis individuals were collected from two locations along Mallorca Island waters attending to different degree of human impact and the hemocytes were obtained. Specimens from the impacted area showed increased activities of the antioxidant enzymes - catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase -, myeloperoxidase activity and reduced glutathione levels. No differences in oxidative damage markers - malondiahdehyde and carbonyl index - were evidenced between the pristine and polluted areas. Hemocytes from the polluted area presented increased capability to generate reactive oxygen species and nitrite/nitrate when activated. In conclusion, the human activities primed hemocytes for oxidative burst and increased the antioxidant mechanism without evidence of oxidative damage.
Show more [+] Less [-]Nitrogen deposition alters nitrogen cycling and reduces soil carbon content in low-productivity semiarid Mediterranean ecosystems Full text
2013
Ochoa-Hueso, Raúl | Maestre, Fernando T. | de los Ríos, Asunción | Valea, Sergio | Theobald, Mark R. | Vivanco, Marta G. | Manrique, Esteban | Bowker, Mathew A.
Anthropogenic N deposition poses a threat to European Mediterranean ecosystems. We combined data from an extant N deposition gradient (4.3–7.3 kg N ha−1 yr−1) from semiarid areas of Spain and a field experiment in central Spain to evaluate N deposition effects on soil fertility, function and cyanobacteria community. Soil organic N did not increase along the extant gradient. Nitrogen fixation decreased along existing and experimental N deposition gradients, a result possibly related to compositional shifts in soil cyanobacteria community. Net ammonification and nitrification (which dominated N-mineralization) were reduced and increased, respectively, by N fertilization, suggesting alterations in the N cycle. Soil organic C content, C:N ratios and the activity of β-glucosidase decreased along the extant gradient in most locations. Our results suggest that semiarid soils in low-productivity sites are unable to store additional N inputs, and that are also unable to mitigate increasing C emissions when experiencing increased N deposition.
Show more [+] Less [-]BaP (PAH) air quality modelling exercise over Zaragoza (Spain) using an adapted version of WRF-CMAQ model Full text
2013
(Roberto),
Benzo(a)pyrene (BaP) is one of the most dangerous PAH due to its high carcinogenic and mutagenic character. Because of this reason, the Directive 2004/107/CE of the European Union establishes a target value of 1 ng/m3 of BaP in the atmosphere.In this paper, the main aim is to estimate the BaP concentrations in the atmosphere by using last generation of air quality dispersion models with the inclusion of the transport, scavenging and deposition processes for the BaP. The degradation of the particulated BaP by the ozone has been considered. The aerosol–gas partitioning phenomenon in the atmosphere is modelled taking into a count that the concentrations in the gas and the aerosol phases. If the pre-existing organic aerosol concentrations are zero gas/particle equilibrium is established.The model has been validated at local scale with data from a sampling campaign carried out in the area of Zaragoza (Spain) during 12 weeks.
Show more [+] Less [-]Fuzzy model for risk assessment of persistent organic pollutants in aquatic ecosystems Full text
2013
Seguí, X. | Pujolasus, E. | Betrò, S. | Àgueda, A. | Casal, J. | Ocampo-Duque, W. | Rudolph, I. | Barra, R. | Páez, M. | Barón, E. | Eljarrat, E. | Barceló, D. | Darbra, R.M.
Fuzzy model for risk assessment of persistent organic pollutants in aquatic ecosystems Full text
2013
Seguí, X. | Pujolasus, E. | Betrò, S. | Àgueda, A. | Casal, J. | Ocampo-Duque, W. | Rudolph, I. | Barra, R. | Páez, M. | Barón, E. | Eljarrat, E. | Barceló, D. | Darbra, R.M.
We developed a model for evaluating the environmental risk of persistent organic pollutants (POPs) to aquatic organisms. The model is based on fuzzy theory and uses information provided by international experts through a questionnaire. It has been tested in two case studies for a particular type of POPs: brominated flame retardants (BFRs). The first case study is related to the EU-funded AQUATERRA project, with sampling campaigns carried out in two Ebro tributaries in Spain (the Cinca and Vero Rivers). The second one, named the BROMACUA project, assessed different aquatic ecosystems in Chile (San Vicente Bay) and Colombia (Santa Marta Marsh). In both projects, the BFRs under study were polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). However, the model can be extrapolated to other POPs and to different aquatic ecosystems to provide useful results for decision-makers.
Show more [+] Less [-]Fuzzy model for risk assessment of persistent organic pollutants in aquatic ecosystems Full text
2013
Seguí, X. | Pujolasus, E. | Betrò, S. | Àgueda, A. | Casal, J. | Ocampo-Duque, William | Rudolph, Ignacio | Barra, Ricardo | Páez, Martha | Barón, Enrique | Eljarrat, Ethel | Barceló, Damià | Darbra, Rosa María
We developed a model for evaluating the environmental risk of persistent organic pollutants (POPs) to aquatic organisms. The model is based on fuzzy theory and uses information provided by international experts through a questionnaire. It has been tested in two case studies for a particular type of POPs: brominated flame retardants (BFRs). The first case study is related to the EU-funded AQUATERRA project, with sampling campaigns carried out in two Ebro tributaries in Spain (the Cinca and Vero Rivers). The second one, named the BROMACUA project, assessed different aquatic ecosystems in Chile (San Vicente Bay) and Colombia (Santa Marta Marsh). In both projects, the BFRs under study were polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). However, the model can be extrapolated to other POPs and to different aquatic ecosystems to provide useful results for decision-makers. © 2013 Elsevier Ltd. All rights reserved. | The authors are grateful for the participation of the 38 scientists who replied to the questionnaire. In addition, the authors would like to thank the Autonomous Government of Catalonia (project No. 2009SGR1118), the BBVA Foundation through the BROMACUA project (Evaluación del impacto ambiental de los retardantes de llama bromados en ecosistemas acuáticos de América Latina) and the European Union under the Global Change and Ecosystems (FP6) Water Cycle and Soil Related Aspects (AQUATERRA, Project number 505428). | Peer Reviewed
Show more [+] Less [-]Hydrogeochemical variables regionalization – applying cluster analysis for a seasonal evolution model from an estuarine system affected by AMD Full text
2013
Grande, J.A. | Carro, B. | Borrego, J. | de la Torre, M.L. | Valente, T. | Santisteban, M.
This study describes the spatial evolution of the hydrogeochemical parameters which characterise a strongly affected estuary by Acid Mine Drainage (AMD). The studied estuarine system receives AMD from the Iberian Pyrite Belt (SW Spain) and, simultaneously, is affected by the presence of an industrial chemical complex. Water sampling was performed in the year of 2008, comprising four sampling campaigns, in order to represent seasonality. The results show how the estuary can be divided into three areas of different behaviour in response to hydrogeochemical variables concentrations that define each sampling stations: on one hand, an area dominated by tidal influence; in the opposite end there is a second area including the points located in the two rivers headwaters that are not influenced by seawater; finally there is the area that can be defined as mixing zone. These areas are moved along the hydrological year due to seasonal chemical variations.
Show more [+] Less [-]Bioavailability of heavy metals in water and sediments from a typical Mediterranean Bay (Málaga Bay, Region of Andalucía, Southern Spain) Full text
2013
Alonso Castillo, M.L. | Sánchez Trujillo, I. | Vereda Alonso, E. | García de Torres, A. | Cano Pavón, J.M.
Concentrations of heavy metals were measured in sediment and water from Málaga Bay (South Spain). In the later twentieth century, cities such as Málaga, have suffered the impact of mass summer tourism. The ancient industrial activities, and the actual urbanization and coastal development, recreation and tourism, wastewaters treatment facilities, have been sources of marine pollution. In sediments, Ni was the most disturbing metal because Ni concentrations exceeded the effects range low (ERL), concentration at which toxicity could start to be observed in 85% of the samples analyzed. The metal bioavailability decreased in the order: Cd>Ni>Pb>Cu>Cr. In the sea water samples, Cd and Pb were the most disturbing metals because they exceeded the continuous criteria concentration (CCC) of US EPA in a 22.5% and 10.0% of the samples, respectively. Statistical analyses (ANOVA, PCA, CA) were performed.
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