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Looking at the aquatic contamination through fish eyes – A faithful picture based on metals burden Texto completo
2013
Pereira, Patrícia | Raimundo, Joana | Canário, João | Almeida, Armando | Pacheco, Mario
Looking at the aquatic contamination through fish eyes – A faithful picture based on metals burden Texto completo
2013
Pereira, Patrícia | Raimundo, Joana | Canário, João | Almeida, Armando | Pacheco, Mario
This study describes for the first time metal accumulation in the eyes of native golden grey mullet (Liza aurata) coupled with water/sediment quality assessment. Sampling was performed in the Tagus estuary (Portugal) where a confined area (Barreiro) is severely contaminated by metal/loids. Levels of As, Cu, Pb, Hg and Cd in sediments from Barreiro were one order of magnitude higher than those from the reference site. Data on water column pointed also to a higher availability of Cu, Pb, Cd and Hg (including MeHg) at Barreiro. Accordingly, fish eyes accumulated higher levels of metal/loids at Barreiro than at the reference site. These findings support the use of fish eyes as a target organ in environmental health assessment since they reflect sediment and water contamination. It points also to the importance of evaluate eye changes at structural/functional levels in order to examine in what extent accumulated metals could compromise this perceptive system.
Mostrar más [+] Menos [-]Looking at the aquatic contamination through fish eyes - a faithful picture based on metals burden Texto completo
2013
Pereira, Patrícia | Raimundo, Joana | Canário, João | Almeida, Armando | Pacheco, Mário
This study describes for the first time metal accumulation in the eyes of native golden grey mullet (Liza aurata) coupled with water/sediment quality assessment. Sampling was performed in the Tagus estuary (Portugal) where a confined area (Barreiro) is severely contaminated by metal/loids. Levels of As, Cu, Pb, Hg and Cd in sediments from Barreiro were one order of magnitude higher than those from the reference site. Data on water column pointed also to a higher availability of Cu, Pb, Cd and Hg (including MeHg) at Barreiro. Accordingly, fish eyes accumulated higher levels of metal/loids at Barreiro than at the reference site. These findings support the use of fish eyes as a target organ in environmental health assessment since they reflect sediment and water contamination. It points also to the importance of evaluate eye changes at structural/functional levels in order to examine in what extent accumulated metals could compromise this perceptive system. | Patrícia Pereira (SFRH/BPD/69563/2010) and Joana Raimundo (SFRH/BPD/91498/2012) benefit from Pos-doctoral grants supported by “Fundação para a Ciência e a Tecnologia” (FCT). This work as been supported by the following projects also funded by FCT: NEUTOXMER “Neurotoxicity of mercury in fish and association with morphofunctional brain alterations and behavior shifts” (PTDC/AAG-REC/2488/2012) and PROFLUX “Processes and fluxes of mercury and methylmercury in a contaminated coastal ecosystem Tagus Estuary, Portugal” (PTDC/MAR/102748/2008). Authors wish to acknowledge Bárbara Anes and Rute Cesário for the fish sampling support. | published
Mostrar más [+] Menos [-]Dispersion model evaluation of PM2.5, NOx and SO2 from point and major line sources in Nova Scotia, Canada using AERMOD Gaussian plume air dispersion model Texto completo
2013
Gibson, Mark D. | Kundu, Soumita | Satish, Mysore
AERMOD was used to model the air dispersion of point and major line emissions of PM2.5 in Halifax and Pictou, NOX in Halifax and SO2 in Halifax, Sydney and Port Hawkesbury, Nova Scotia, Canada. Emission inventory data for 2004 were used in simulations within four, 50 km x 50 km, domains over annual, monthly and 1–hour averaging periods. Annual averaged surface concentration maps are reported. Modeled versus observed comparisons were made within each domain at the Government, National Air Pollution Surveillance (NAPS) monitoring sites (discrete receptors). Evaluation of the model was conducted on the annual, monthly and hourly results using a number of statistical methods that included R2, fractional bias, normalized mean square error and the fraction of predictions within a factor of two of the observations. The AERMOD model evaluation showed that there was good agreement between the modeled and observed SO2 concentration for the annual and monthly comparison but less skill at estimating the hourly comparisons for SO2 in Halifax and Sydney. AERMOD showed poor model skill at predicting SO2 in Port Hawkesbury over the same averaging periods. The model evaluation for PM2.5 in Halifax, PM2.5 in Pictou and NOX in Halifax showed poor agreements and model skill. The surface concentrations from the point and major lines sources in all domains from all metrics were found to be well below the National Air Quality Standards. AERMOD has shown its utility as a suitable model for conducting dispersion modeling from point and line sources in Nova Scotia with good model skill for estimating annual and monthly SO2 concentrations in Halifax and Sydney. The study highlights the validity of using emission inventory data to estimate the surface impact of major point and line sources within domains containing complex terrain, differing land use types and with large variability within the annual meteorology.
Mostrar más [+] Menos [-]Estimation of atmospheric PCB releases from industrial facilities in Turkey Texto completo
2013
Kuzu, S Levent | Saral, Arslan | Demir, Selami | Coltu, Hatice | Can, Merve | Beyaz, Tugba
PCB production reduced or stopped in most countries in the late 1970s. According to the Stockholm Convention all the party countries have to list their PCB containing equipment and prepare national inventories. A national implementation plan was prepared in Turkey however, this plan is inadequate. Furthermore, there has not been any information prepared about stationary emission sources, contributing to atmospheric PCB inputs so far. It is aimed in this study to meet this deficit. This study will also help to make stronger comments on identifying sources of atmospheric PCB concentrations. PCB emission factors were utilized to determine the emissions. An average of 920 kg yr–1 of PCB emission is estimated in this study within the borders of Turkey. Highest contribution occurs in Kocaeli located on the North–West of the country by 47% of the overall emissions. Secondary most pollutant site is determined to be Aliaga on the west of the country. Both of this regions are heavily, industrialized and several different industrial processes are present. Iron–steel manufacturing and copper smelting processes comprises the 94% of the PCB releases from stationary sources. A simple box model was applied at two hot spots to determine potential contribution of the estimated emissions to atmospheric concentrations. In Dilovasi, the average contribution from industrial sources was determined as 244 pg m–3 while the average contribution for Aliaga was calculated as 126 pg m–3 within a 50 km x 50 km grid.
Mostrar más [+] Menos [-]Tracing organic matter removal in polluted coastal waters via floating bed phytoremediation Texto completo
2013
Huang, Lingfeng | Zhuo, Jianfu | Guo, Weidong | Spencer, Robert G.M. | Zhang, Zhiying | Xu, Jing
Organic matter removal by cultured Sesuvium portulacastrum in constructed floating beds was studied during a 20day greenhouse experiment and an 8month field campaign in the polluted Yundang Lagoon (southeastern China). Experiments were traced via dissolved organic carbon (DOC) concentration, fluorescence excitation–emission matrix and absorption spectroscopy. Two ‘terrestrial’ humic-like, one ‘marine’ humic-like and one protein-like components were identified by parallel factor analysis. The ‘terrestrial’ humic-like and protein-like components, DOC and absorption coefficient (a280) decreased during the greenhouse experiment. The intensities of four fluorescence components were all reduced during the field experiment. These results demonstrate the clear potential of floating bed phytoremediation techniques for reducing organic pollution degree in brackish environments. The rhizosphere may play an important role during phytoremediation. Our results show that spectrophotometric measurements such as fluorescence provide a useful tool for examining the removal of different organic moieties during various bioremediation processes.
Mostrar más [+] Menos [-]Contamination levels and spatial distributions of heavy metals and PAHs in surface sediment of Imam Khomeini Port, Persian Gulf, Iran Texto completo
2013
Abdollahi, Sajad | Raoufi, Zeinab | Faghiri, Iraj | Savari, Ahmad | Nikpour, Yadolah | Mansouri, Ali
Imam Khomeini Port (IKP) is the largest Iranian commercial port. Because of many petrochemical industries and urban areas are located around this port and also having heavy ship traffic, concentrations of PAHs, mercury and other heavy metals were measured as the first time in surface sediment of the jetties. The highest concentrations of PAHs, Hg, Cu, Pb and Fe were recorded at Site 1, located in the vicinity of the petrochemical industrial zone, where ships are repaired. The highest concentration of Zn was found at Site 4, which is the jetty for loading mineral materials. The comparison between measured values in this study and some sediment quality guidelines indicated that the concentrations of mercury and PAHs are much higher than other studies. Also, the ratios of PAHs in the stations showed a mixture of both of pyrolytic and petrogenic sources with a dominance of pyrolytic sources.
Mostrar más [+] Menos [-]Recent innovation in microbial source tracking using bacterial real-time PCR markers in shellfish Texto completo
2013
Mauffret, Aourell | Mieszkin, Sophie | Morizur, Mael | Alfiansah, Yustian Rovi | Lozach, Solen | Gourmelon, Michele
We assessed the capacity of real-time PCR markers to identify the origin of contamination in shellfish. Oyster, cockles or clams were either contaminated with fecal materials and host-associated markers designed from Bacteroidales or Catellicoccus marimammalium 16S RNA genes were extracted from their intravalvular liquid, digestive tissues or shellfish flesh. Extraction of bacterial DNA from the oyster intravalvular liquid with FastDNA spin kit for soil enabled the selected markers to be quantified in 100% of artificially contaminated samples, and the source of contamination to be identified in 13 out of 38 naturally contaminated batches from European Class B and Class C areas. However, this protocol did not enable the origin of the contamination to be identified in cockle or clam samples. Although results are promising for extracts from intravalvular liquid in oyster, it is unlikely that a single protocol could be the best across all bacterial markers and types of shellfish. (C) 2013 Elsevier Ltd. All rights reserved.
Mostrar más [+] Menos [-]Merchant ships discharging unwanted marine species in close proximity of a French aquaculture area: Risks involved Texto completo
2013
Masson, Daniel | Thomas, Gerard | Genauzeau, Sylvie | Le Moine, Olivier | Derrien, Annick
The most important oyster farming area in Europe is in a close proximity of two medium size merchant ports. Cargo ships deballast in this area before loading, releasing unwanted or noxious marine species. During a sampling campaign aboard these arriving ships, we found in some ballast water samples a huge number of potentially toxic dinoflagellates and some potentially pathogenic bacteria. A model was applied to find the potential geographical spread of the discharged ballast water. This model predicts the water to reach highly vulnerable shellfish farmed areas in six to eight days.
Mostrar más [+] Menos [-]Macrobenthos habitat potential mapping using GIS-based artificial neural network models Texto completo
2013
Lee, Saro | Park, Inhye | Koo, Bon Joo | Ryu, Joo-Hyung | Choi, Jong-Kuk | Woo, Han Jun
This paper proposes and tests a method of producing macrobenthos habitat potential maps in Hwangdo tidal flat, Korea based on an artificial neural network. Samples of macrobenthos were collected during field work, and eight control factors were compiled as a spatial database from remotely sensed data and GIS analysis. The macrobenthos habitat potential maps were produced using an artificial neural network model. Macrobenthos habitat potential maps were made for Macrophthalmus dilatatus, Cerithideopsilla cingulata, and Armandia lanceolata. The maps were validated by compared with the surveyed habitat locations. A strong correlation between the potential maps and species locations was revealed. The validation result showed average accuracies of 74.9%, 78.32%, and 73.27% for M. dilatatus, C. cingulata, and A. lanceolata, respectively. A GIS-based artificial neural network model combined with remote sensing techniques is an effective tool for mapping the areas of macrobenthos habitat potential in tidal flats.
Mostrar más [+] Menos [-]Characterization of an estuarine environment by means of an index based on intertidal macrofauna Texto completo
2013
Conde, Anxo | Novais, Júlio M. | Dominguez, Jorge
Macrobenthic intertidal assemblages from five Atlantic Iberian estuaries were analyzed to develop an estuarine index. An R-mode analysis revealed a close association between the isopod Cyathura carinata, the polychaete Hediste diversicolor and the bivalve Scrobicularia plana. Although these species are abundant in all the estuaries considered, they tend to be absent from sites at the marine and freshwater ends of the environmental gradient. Three different ways of calculating the estuarine index are proposed. The index is comprised in the interval [0,1] and was constructed using relative abundances rather than absolute abundances. Transformation of the raw data helped improve the performance of the index. A non-parametric statistical test is proposed for application to the estuarine index to find sites with the same values after a significant omnibus test. The index appears to be a good proxy for recognizing estuarine limits by use of indicator species.
Mostrar más [+] Menos [-]Bioavailability of trace elements in surface sediments from Kongsfjorden, Svalbard Texto completo
2013
Grotti, Marco | Soggia, Francesco | Ianni, Carmela | Magi, Emanuele | Udisti, Roberto
The bioavailability of trace elements in marine sediments from Kongsfjorden (Svalbard Islands, Norwegian Arctic) was assessed and discussed. Total concentrations of several elements were determined in two granulometric fractions and their bioavailability evaluated by both applying a sequential-selective extraction procedure and using a biomimetic approach based on proteolytic enzymes. Total concentration values and solid speciation patterns indicated overall that the anthropogenic impact of trace elements in the investigated area is negligible, although a minor enrichment with respect to crustal values was found for As, Cd, Cr, Ni, and V. Enrichment of trace elements in the <63-μm fraction compared to the coarser one was evident for As, Cd, Cr, and Ni. The evaluation of the bioavailable fractions showed that a large part of the total content of trace elements cannot enter the aquatic food chain and emphasised the risk of overestimating the environmental impact of heavy metals if the assessment is only based on total concentrations.
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