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Evaluating legacy contaminants and emerging chemicals in marine environments using adverse outcome pathways and biological effects-directed analysis 全文
2013
Hutchinson, Thomas H. | Lyons, Brett P. | Thain, John E. | Law, Robin J.
Natural and synthetic chemicals are essential to our daily lives, food supplies, health care, industries and safe sanitation. At the same time protecting marine ecosystems and seafood resources from the adverse effects of chemical contaminants remains an important issue. Since the 1970s, monitoring of persistent, bioaccumulative and toxic (PBT) chemicals using analytical chemistry has provided important spatial and temporal trend data in three important contexts; relating to human health protection from seafood contamination, addressing threats to marine top predators and finally providing essential evidence to better protect the biodiversity of commercial and non-commercial marine species. A number of regional conventions have led to controls on certain PBT chemicals over several years (termed ‘legacy contaminants’; e.g. cadmium, lindane, polycyclic aromatic hydrocarbons [PAHs] and polychlorinated biphenyls [PCBs]). Analytical chemistry plays a key role in evaluating to what extent such regulatory steps have been effective in leading to reduced emissions of these legacy contaminants into marine environments. In parallel, the application of biomarkers (e.g. DNA adducts, CYP1A-EROD, vitellogenin) and bioassays integrated with analytical chemistry has strengthened the evidence base to support an ecosystem approach to manage marine pollution problems. In recent years, however,the increased sensitivity of analytical chemistry, toxicity alerts and wider environmental awareness has led to a focus on emerging chemical contaminants (defined as chemicals that have been detected in the environment, but which are currently not included in regulatory monitoring programmes and whose fate and biological impacts are poorly understood). It is also known that natural chemicals (e.g. algal biotoxins) may also pose a threat to marine species and seafood quality. Hence complex mixtures of legacy contaminants, emerging chemicals and natural biotoxins in marine ecosystems represent important scientific, economic and health challenges. In order to meet these challenges and pursue cost-effective scientific approaches that can provide evidence necessary to support policy needs (e.g. the European Marine Strategy Framework Directive), it is widely recognised that there is a need to (i) provide marine exposure assessments for priority contaminants using a range of validated models, passive samplers and biomarkers; (ii) integrate chemical monitoring data with biological effects data across spatial and temporal scales (including quality controls); and (iii) strengthen the evidence base to understand the relationship between exposure to complex chemical mixtures, biological and ecological impacts through integrated approaches and molecular data (e.g. genomics, proteomics and metabolomics). Additionally, we support the widely held view that (iv) that rather than increasing the analytical chemistry monitoring of large number of emerging contaminants, it will be important to target analytical chemistry towards key groups of chemicals of concern using effects-directed analysis. It is also important to evaluate to what extent existing biomarkers and bioassays can address various classes of emerging chemicals using the adverse outcome pathway (AOP) approach now being developed by the Organization for Economic Cooperation and Development (OECD) with respect to human toxicology and ecotoxicology.
显示更多 [+] 显示较少 [-]Source apportionment of sedimentary hydrocarbons in the Segara Anakan Nature Reserve, Indonesia 全文
2013
Syakti, Agung Dhamar | Hidayati, Nuning Vita | Hilmi, Endang | Piram, Anne | Doumenq, Pierre
The study aimed to determine the spatial distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Segara Anakan nature reserve and their potential origins using gas chromatography–mass spectrometry. Total alkane concentrations ranged from 3755 to 129,027μgkg−1, and the concentrations of 16 PAHs ranged from 375 to 29,517μgkg−1. The ratios of specific n-alkanes (e.g., CPI24–34, WaxCn, and Paq), including a new proposed index, terrestrial–marine discriminant (TMD), as well as the ratios of selected PAHs (e.g., Ant/∑178, Fl/∑202, BaAnt/∑228, and IPyr/∑276), showed that the sources of hydrocarbons in the sediments were generally biogenic, including both terrigenous and marine, with an anthropogenic pyrolytic contribution (petrogenic and biogenic combustion). For the environmental risk assessment, a sediment quality guideline (SQGs) comparison indicated that the station risk levels ranged from low to medium-low, except for R6, which has a greater impact on the ecological risk for marine organisms.
显示更多 [+] 显示较少 [-]Coupled hydrodynamic and wastewater plume models of Belfast Lough, Northern Ireland: A predictive tool for future ecological studies 全文
2013
Pritchard, Daniel | Savidge, Graham | Elsäßer, Björn
Wastewater outfalls provide a natural laboratory for the study of nutrient dynamics in coastal seas, however if properly designed and operated their impact can be difficult to detect. A model was developed and applied to investigate the effect of variation in hydrodynamic conditions on the transport and dilution of a treated wastewater plume in Belfast Lough, Northern Ireland. To validate these predictions we measured the physiochemical properties of the waters surrounding the outfall with a specific focus on inherent plume tracers likely to be relevant to the study of macroalgae (salinity, nitrogen and phosphorus). The model performed well and our data show high dilution of the plume, even under neap-tide conditions. This provides a spatially and temporally defined predictive framework for future studies investigating the compliance of Northern Ireland’s coastal waters with European Water Framework Directive objectives and for feasibility studies investigating macroalgal aquaculture near wastewater outfalls.
显示更多 [+] 显示较少 [-]Kinetics of the PO4-P adsorption onto soils and sediments from the Mondego estuary (Portugal) 全文
2013
Otero, M. | Coelho, J.P. | Rodrigues, E.T. | Pardal, M.A. | Santos, E.B.H. | Esteves, V.I. | Lillebø, A.I.
Kinetics of the PO4-P adsorption onto soils and sediments from the Mondego estuary (Portugal) 全文
2013
Otero, M. | Coelho, J.P. | Rodrigues, E.T. | Pardal, M.A. | Santos, E.B.H. | Esteves, V.I. | Lillebø, A.I.
In order to assess the status of a North Atlantic Ocean Ecoregion (Mondego system, Portugal) after the implementation of a management programme, a study on PO4-P sorption was carried out. Considering that sorption velocity markedly determines the systems promptness to phosphorus external loading, the kinetics of the sorption of PO4-P onto estuarine sediments and the upstream agricultural soils was studied. The pseudo-second order kinetic equation gave an appropriate description of PO4-P sorption onto these soils and sediments, allowing for a quantitative comparison. For soils, the kinetic constants (k2⁎, μg−1gh−1) ranged between 0.007 and 0.017μg−1gh−1 while, in the case of sediments these ranged between 0.008 and 0.012μg−1gh−1. Results showed that the reduction of water residence time after the management action was relevant for the system status, affecting its reaction capacity to phosphorus loading.
显示更多 [+] 显示较少 [-]Kinetics of the PO4-P adsorption onto soils and sediments from the Mondego estuary (Portugal) 全文
2013
Otero, M. | Coelho, J. P. | Rodrigues, E. T. | Pardal, M. A. | Santos, E. B. H. | Esteves, V. I. | Lillebø, A. I.
In order to assess the status of a North Atlantic Ocean Ecoregion (Mondego system, Portugal) after the implementation of a management programme, a study on PO4-P sorption was carried out. Considering that sorption velocity markedly determines the systems promptness to phosphorus external loading, the kinetics of the sorption of PO4-P onto estuarine sediments and the upstream agricultural soils was studied. The pseudo-second order kinetic equation gave an appropriate description of PO4-P sorption onto these soils and sediments, allowing for a quantitative comparison. For soils, the kinetic constants (k2*, μg-1gh-1) ranged between 0.007 and 0.017μg-1gh-1while, in the case of sediments these ranged between 0.008 and 0.012μg-1gh-1. Results showed that the reduction of water residence time after the management action was relevant for the system status, affecting its reaction capacity to phosphorus loading. | The authors want to acknowledge financial support from FCT (Fundação para a Ciência e a Tecnologia) to CESAM (Centre for Environmental and Marine Studies) and to IMAR (Institute of Marine Research). The Post-Doc grant SFRH/BPD/48449/2008 (P. Coelho) funded by FCT is also acknowledged. Also, Marta Otero acknowledges support from the Spanish Ministry of Science and Innovation (RYC-2010-05634). Special thanks are given go to Dr José Raposo for drawing Fig. 1. | published
显示更多 [+] 显示较少 [-]Titanium determination by multisyringe flow injection analysis system and a liquid waveguide capillary cell in solid and liquid environmental samples 全文
2013
Sánchez-Quiles, David | Tovar-Sánchez, Antonio | Horstkotte, Burkhard
Titanium determination by multisyringe flow injection analysis system and a liquid waveguide capillary cell in solid and liquid environmental samples 全文
2013
Sánchez-Quiles, David | Tovar-Sánchez, Antonio | Horstkotte, Burkhard
A multisyringe flow injection analysis system using a liquid waveguide capillary cell (MSFIA-LWCC) has been used for the spectrophotometric determination of titanium (Ti) in marine environmental samples. Samples were previous digested using potassium peroxodisulfate (K2S2O8). The method showed to be linear over a range up to 1μM with a detection limit of 9.2nM. The analysis consumes little reagent (250μL) and sample (600μL). It had an adequate accuracy with high repeatability (RSD of 1.8%) for all marine samples. The proposed method was used to evaluate the concentration of Ti in natural samples collected in the coastal area of the Majorca Island (Western Mediterranean Sea). We report average concentrations of Ti in coastal surface microlayer of 510.7±267.2nM, in surface sediments of 2.72±1.84μmol/g, and in rhizomes and leaves of Posidonia oceanica of 310±295nmol/g and 157±132nmol/g, respectively.
显示更多 [+] 显示较少 [-]Titanium determination by multisyringe flow injection analysis system and a liquid waveguide capillary cell in solid and liquid environmental samples 全文
2013
Sánchez-Quiles, David | Tovar-Sánchez, Antonio | Horstkotte, Burkhard
A multisyringe flow injection analysis system using a liquid waveguide capillary cell (MSFIA-LWCC) has been used for the spectrophotometric determination of titanium (Ti) in marine environmental samples. Samples were previous digested using potassium peroxodisulfate (K2S2O8). The method showed to be linear over a range up to 1μM with a detection limit of 9.2nM. The analysis consumes little reagent (250μL) and sample (600μL). It had an adequate accuracy with high repeatability (RSD of 1.8%) for all marine samples. The proposed method was used to evaluate the concentration of Ti in natural samples collected in the coastal area of the Majorca Island (Western Mediterranean Sea). We report average concentrations of Ti in coastal surface microlayer of 510.7±267.2nM, in surface sediments of 2.72±1.84μmol/g, and in rhizomes and leaves of Posidonia oceanica of 310±295nmol/g and 157±132nmol/g, respectively. © 2013 Elsevier Ltd. | This work was supported by the ISUMAR project (CTM2011-22645) funded by the Spanish Ministry of Economy and Competitiveness. We thank M. Makhani for assistance and J.F. González (SCT – UIB) for technical assistance. D.S.-Q. was supported by the JAE-predoc program of the Spanish National Research Council (CSIC). B.H. was supported by JAEDOC 2008 program (CSIC). | Peer reviewed
显示更多 [+] 显示较少 [-]Sedimentary PBDEs in urban areas of tropical Asian countries 全文
2013
Kwan, Charita S. | Takada, Hideshige | Mizukawa, Kaoruko | Saha, Mahua | Rinawati, | Santiago, Evangeline C.
Polybrominated diphenyl ethers (PBDEs) were measured in surface sediment samples collected from urban canals or rivers in Lao PDR, Cambodia, Vietnam, India, Indonesia, Thailand, the Philippines, Malaysia and Japan. The total PBDE concentrations in the sediments ranged from 0.83 to 3140ng/g dry wt. BDE-209 was predominant, ranging from 43% to 97% of total PBDEs, followed by nona-BDEs and some detectable concentrations of BDEs 47, 49, 99, 100, 153, 154 and 183. Sedimentary PBDE levels in Malaysia, Cambodia, the Philippines and Thailand were generally higher than those reported for highly industrialized countries. Spatial distribution of PBDEs indicated that inland sources may impact coastal areas. The presence of BDE congeners which are not contained in technical mixtures and the higher proportions of nona-BDEs relative to BDE-209 in the sediments were identified as indicators of debromination. BDE-209 was possibly debrominated under anaerobic conditions in some of the sediment samples.
显示更多 [+] 显示较少 [-]Good Environmental Status of marine ecosystems: What is it and how do we know when we have attained it? 全文
2013
Borja, Angel | Elliott, Mike | Andersen, Jesper H. | Cardoso, Ana C. | Carstensen, Jacob | Ferreira, João G. | Heiskanen, Anna-Stiina | Marques, João C. | Neto, João M. | Teixeira, Heliana | Uusitalo, Laura | Uyarra, María C. | Zampoukas, Nikolaos
The European Marine Strategy Framework Directive (MSFD) requires EU Member States (MS) to achieve Good Environmental Status (GEnS) of their seas by 2020. We address the question of what GEnS entails especially with regard to the level at which targets are set (descriptors, criteria, indicators), to scales for assessments (regional, sub-divisions, site-specific), and to difficulties in putting into practice the GEnS concept. We propose a refined and operational definition of GEnS, indicating the data and information needed to all parts of that definition. We indicate the options for determining when GEnS has been met, acknowledge the data and information needs for each option, and recommend a combination of existing quantitative targets and expert judgement. We think that the MSFD implementation needs to be less complex than shown for other similar directives, can be based largely on existing data and can be centred on the activities of the Regional Seas Conventions.
显示更多 [+] 显示较少 [-]Polybrominated diphenyl ethers in fat samples from White-chinned Petrels (Procellaria aequinoctialis) and Spectacled Petrels (P. conspicillata) off southern Brazil 全文
2013
Cipro, Caio V.Z. | Colabuono, Fernanda I. | Taniguchi, Satie | Montone, Rosalinda C.
Polybrominated diphenyl ethers (PBDEs) have been gaining much visibility in environmental chemical studies due to their similarity to PCBs and growing reports of harmful effects. The fact that these contaminants have not yet undergone bans or restrictions on the global level underscores the need for data on their occurrence. In the present study, fat samples from 26 White-chinned Petrels (Procellaria aequinoctialis) and 3 Spectacled Petrels (P. conspicillata) collected dead ashore or as bycatch of longline fisheries in southern Brazil were analyzed to determine concentrations of seven congeners (IUPAC #28, 47, 99, 100, 153, 154 and 183). Concentrations of ΣPBDEs ranged from not detectable to 72.70ngg−1 (wet weight), comparatively lower than concentrations reported for seabird samples in northern hemisphere. The most detected congeners were 153, 154 and 183. This pattern is close to that previously reported for birds of the same group, but not those from the same region.
显示更多 [+] 显示较少 [-]Legacy contaminant bioaccumulation in rock crabs in Sydney Harbour during remediation of the Sydney Tar Ponds, Nova Scotia, Canada 全文
2013
Walker, Tony R. | MacAskill, Devin | Weaver, Peter
Concentrations of PAHs, PCBs, metals and lipids in hepatopancreas of rock crabs (Cancer irroratus) were measured in Sydney Harbour (SH) for one year prior to remediation and three years of remediation of the Sydney Tar Ponds (STP), Nova Scotia. Low level concentrations of PCBs and metals were measured, although PAHs were mostly undetected. Metal concentrations showed little spatio-temporal variability, although highest concentrations of As, Cd and Cu were measured at reference stations furthest from the STP remediation site. Mercury concentrations were at least an order of magnitude lower than Canadian guidelines. Moderately elevated PCB concentrations were detected in crabs near Muggah Creek, but these were generally not higher than those measured during baseline. Despite remediation activities, current contaminant burdens measured in crabs were much lower than previously reported in other studies of crabs and lobster in industrial harbours in eastern Canada, due in part to natural recovery of SH sediments.
显示更多 [+] 显示较少 [-]Estimating sub-surface dispersed oil concentration using acoustic backscatter response 全文
2013
Fuller, Christopher B. | Bonner, James S. | Islam, Mohammad S. | Page, Cheryl | Ojo, Temitope | Kirkey, William
The recent Deepwater Horizon disaster resulted in a dispersed oil plume at an approximate depth of 1000m. Several methods were used to characterize this plume with respect to concentration and spatial extent including surface supported sampling and autonomous underwater vehicles with in situ instrument payloads. Additionally, echo sounders were used to track the plume location, demonstrating the potential for remote detection using acoustic backscatter (ABS). This study evaluated use of an Acoustic Doppler Current Profiler (ADCP) to quantitatively detect oil-droplet suspensions from the ABS response in a controlled laboratory setting. Results from this study showed log-linear ABS responses to oil-droplet volume concentration. However, the inability to reproduce ABS response factors suggests the difficultly in developing meaningful calibration factors for quantitative field analysis. Evaluation of theoretical ABS intensity derived from the particle size distribution provided insight regarding method sensitivity in the presence of interfering ambient particles.
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