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Concentration profiles of PCB congeners in the blubber and liver of Steller sea lions (Eumetopias jubatus) from the coast of Hokkaido, Japan Texte intégral
2013
Kubo, Keiko | Yamaguchi, Katsuyuki | Mitsuhashi, Masaki | Hattori, Kaoru | Tanaka, Shunitz
The concentrations of PCB congeners in the blubber and liver of male and female Steller sea lions (Eumetopias jubatus; SSLs) collected from the Shakotan Peninsula and the Nemuro Strait, Hokkaido, Japan in 2008 and 2010 were measured by HRGC–HRMS, in order to express the concentration profiles in SSLs at these regions. #153 predominated in both organs, followed by #138, #99 and #118. In males, #28 and #31 were concentrated particularly in the blubber, while #177 and #199 were accumulated specifically in the liver. The differences in these concentration profiles might be expressed by the differences in the organs and their functions. The concentrations of #99, #118, #138, #153, and #180 in the blubber appeared to correspond significantly with the differences between genders. The details of the surveys on PCB congeners in SSLs could clarify the differences in the residue levels of individual congeners for organs and genders.
Afficher plus [+] Moins [-]Occurrence, distribution, and bioaccumulation of antibiotics in coastal environment of Dalian, China Texte intégral
2013
Na, Guangshui | Fang, Xiaodan | Cai, Yaqi | Ge, Linke | Zong, Humin | Yuan, Xiutang | Yao, Ziwei | Zhang, Zhifeng
Seawater, sediment, and aquatic organism samples were collected from 20 sampling sites in coastal environment of Dalian in August, 2011. The occurrence, distribution, and bioaccumulation of 20 antibiotics categorizing into three groups, including 14 sulfonamides (SAs), two chloramphenicols (CAPs) and four tetracyclines (TCs), were investigated. The results suggested that tetracyclines were the predominant antibiotics in the seawater (range: 2.11–9.23ngL−1), while sulfonamides were the dominant antibiotics in both sediments (range: 1.42–71.32μgkg−1) and aquatic organisms (range: 2.18–63.87μgkg−1). The sorption coefficient Kd,s values revealed that sulfameter, sulfadiazine, sulfamethoxypyridazine, sulfamonomethoxine, chloramphenicol, and doxycycline presented higher sorption capacities than the other antibiotics. The average BAFs suggested that sulfamethazine, sulfamethiazole, sulfamonomethoxine, and doxycycline were potentially bioaccumulative, while sulfadiazine, sulfameter, sulfamethoxypyridazine, and chloramphenicol were bioaccumulative.
Afficher plus [+] Moins [-]Antibiotic resistance of Shewanella putrefaciens isolated from shellfish collected from the West Sea in Korea Texte intégral
2013
Kang, Chang-Ho | Shin, Yujin | Jeon, HanEul | Choi, Jae-Ho | Jeong, SuYeon | So, Jae-Seong
In this study, we isolated and characterized Shewanella putrefaciens from shellfish harvested from the West Sea in Korea. For the initial isolation of S. putrefaciens, LB agar plates supplemented with ferrous sulfate and sodium thiosulfate were inoculated with shellfish homogenates, incubated for 24h, and then black colonies were selected. Gram-negative and catalase-positive colonies were subsequently confirmed by PCR assays and API 20E kit test system. The Shewanella-specific 16S rRNA and gyrB genes were used to design S. putrefaciens-specific PCR primers. From 6 species of shellfish tested, 24 S. putrefaciens strains were isolated. These 24 isolates had the following profiles of resistance against 16 antibiotics: all the isolates were resistant to cephalothin and vancomycin and 95.8% were resistant to ampicillin. Here, we report the isolation of S. putrefaciens from shellfish and our results point to a new possible route for exposing healthy individuals to S. putrefaciens.
Afficher plus [+] Moins [-]Multifractal analysis of ground–level ozone concentrations at urban, suburban and rural background monitoring sites in Southwestern Iberian Peninsula Texte intégral
2013
Pavon-Dominguez, Pablo | Jimenez-Hornero, Francisco J. | Gutierrez de Rave, Eduardo
This paper seeks to enhance understanding of the data distribution of ground–level ozone time series by analysing their multifractal spectra. Emphasis is placed on the suitability of the box–counting and moments methods for characterizing scaling properties of ozone concentration, enabling us to describe similarities and differences inferred from the multifractal spectra by analysing various types of monitoring stations (urban, suburban and rural monitoring sites) under identical atmospheric conditions. It is herein demonstrated that that multifractal features are to a considerable extent similar for each type of monitoring station under warm atmospheric conditions and high solar radiation, owing to the fact that these weather characteristics homogenize the scaling behaviour of ozone. On the contrary, location and chemical precursors play a more prominent role under low temperatures and solar radiation, highlighting differences among multifractal features of ozone concentrations in the monitoring sites. At rural stations, the absence of anthropogenic emissions promotes less variability in ozone data and homogenization of multifractal behaviour throughout the year. Furthermore, a data shuffling procedure was performed in order to analyse changes occurring in multifractal spectra as time series are subjected to varying degrees of data position disturbance. Results indicate that multifractal analysis is a useful tool for describing the temporal scaling behaviour of ozone time series at different monitoring sites which refines results that have been traditionally provided by statistical analyses on ozone pollution.
Afficher plus [+] Moins [-]Marine water quality monitoring: A review Texte intégral
2013
Karydis, Michael | Kitsiou, Dimitra
Marine water quality monitoring is performed for compliance with regulatory issues, trend detection, model validation and assessment of the effectiveness of adopted policies. As the end users are managers and policy makers, the objectives should be of practical interest and the answers should reduce the uncertainty concerning environmental impact, supporting planning and decision making. Simple and clearcut answers on environmental issues require synthesis of the field information using statistics, simulation models and multiple criteria analysis (MCA). Statistics is easy to apply whereas simulation models enable researchers to forecast future trends as well as test different scenarios. MCA allows the co-estimation of socio-economic variables providing a compromise between scientists’ and policy makers’ priorities. In addition, stakeholders and the public have the right to know and participate. This article reviews marine water quality monitoring principles, design and data analysis procedures. A brief review of international conventions of regional seas is also included.
Afficher plus [+] Moins [-]Disinfection by-products and ecotoxicity of ballast water after oxidative treatment – Results and experiences from seven years of full-scale testing of ballast water management systems Texte intégral
2013
Delacroix, Stephanie | Vogelsang, Christian | Tobiesen, August | Liltved, Helge
Disinfection by-products and ecotoxicity of ballast water after oxidative treatment – Results and experiences from seven years of full-scale testing of ballast water management systems Texte intégral
2013
Delacroix, Stephanie | Vogelsang, Christian | Tobiesen, August | Liltved, Helge
Since 2005, five different ballast water management systems (BWMSs) based on chlorination treatment have been tested by Norwegian Institute for Water Research (NIVA) according to guidelines from the International Maritime Organization (IMO). 25% and >50% of all the tested discharge samples exhibited acute and chronic toxic effects on algae, respectively. In most cases this toxicity was plausibly caused by a high free residual oxidant (FRO) level (>0.08mgCl/l). Of the 22 disinfection by-products (DBPs) that were identified in treated water at discharge, four compounds were at times found at concentrations that may pose a risk to the local aquatic environment. However, there seemed to be no clear indication that the measured DBP concentrations contributed to the observed algal toxicity. The addition of methylcellulose instead of lignin in the test water to comply with IMO requirements seemed to limit the formation of DBP.
Afficher plus [+] Moins [-]Disinfection by-products and ecotoxicity of ballast water after oxidative treatment – Results and experiences from seven years of full-scale testing of ballast water management systems Texte intégral
2013
Delacroix, Stephanie | Vogelsang, Christian | Tobiesen, August | Liltved, Helge
Since 2005, five different ballast water management systems (BWMS) based on chlorination treatment have been tested by Norwegian Institute for Water Research (NIVA) according to guidelines from the International Maritime Organization (IMO). 25 % and >50 % of all the tested discharge samples exhibited acute and chronic toxic effects on algae, respectively. In most cases this toxicity was plausibly caused by a high free residual oxidant (FRO) level (>0.08 mg Cl/l). Of the 22 disinfection by-products (DBPs) that were identified in treated water at discharge, four compounds were at times found at concentrations that may pose a risk to the local aquatic environment. However, there seemed to be no clear indication that the measured DBP concentrations contributed to the observed algal toxicity. The addition of methylcellulose instead of lignin in the test water to comply with IMO requirements seemed to limit the formation of DBP.
Afficher plus [+] Moins [-]Isotopic signatures of eelgrass (Zostera marina L.) as bioindicator of anthropogenic nutrient input in the western Baltic Sea Texte intégral
2013
Schubert, Philipp R. | Karez, Rolf | Reusch, Thorsten B.H. | Dierking, Jan
Eutrophication is a global environmental problem. Better management of this threat requires more accurate assessments of anthropogenic nitrogen (N) inputs to coastal systems than can be obtained with traditional measures. Recently, primary producer N isotopic signatures have emerged as useful proxy of such inputs. Here, we demonstrated for the first time the applicability of this method using the widespread eelgrass (Zostera marina) in the highly eutrophic Baltic Sea. Spatial availability of sewage N across a bay with one major sewage outflow predicted by eelgrass δ15N was high near and downstream of the outflow compared to upstream, but returned to upstream levels within 4km downstream from the outfall. General conclusions were corroborated by traditional eutrophication measures, but in contrast to these measures were fully quantitative. Eelgrass N isotope ratios therefore show high potential for coastal screens of eutrophication in the Baltic Sea, and in other areas with eelgrass meadows.
Afficher plus [+] Moins [-]Testing different ecological scenarios in a temperate estuary: A contribution towards the implementation of the Ecological Potential assessment Texte intégral
2013
Veríssimo, Helena | Patrício, Joana | Teixeira, Heliana | Carriço, Ana | Marques, João Carlos
The concept of Ecological Potential was explored using the macrobenthic communities of the Mondego estuary (Portugal). Different scenarios (loss of a primary producer and intertidal habitat, and habitat modification due to hydromorphological changes and continued press perturbation) were tested to predict changes in the biology if hydromorphological pressures could be reversed, assuming that differences with and without the pressure could indicate the potential.Results showed noticeable changes in the system biology in each scenario. The approach followed, indicates that when data sets exist, differences in the measurement of ecological status with and without the hydromorphological change could be a way forward to determine the potential. In the particular case of the Mondego estuary, the South arm (physically unaltered water body) proved to be richer than the North (HMWB). For the Ecological Potential determination, the South arm could thus be used to derive and adjust future reference conditions for the North.
Afficher plus [+] Moins [-]An ecotoxicological analysis of the sediment quality in a European Atlantic harbor emphasizes the current limitations of the Water Framework Directive Texte intégral
2013
Gonçalves, Sandra F. | Calado, Ricardo | Gomes, Newton C.M. | Soares, Amadeu M.V.M. | Loureiro, Susana
An ecotoxicological analysis of the sediment quality in a European Atlantic harbor emphasizes the current limitations of the Water Framework Directive Texte intégral
2013
Gonçalves, Sandra F. | Calado, Ricardo | Gomes, Newton C.M. | Soares, Amadeu M.V.M. | Loureiro, Susana
The “PortoNovo” project was developed to standardize the methodologies for water quality management in the port areas of coastal Atlantic regions to improve the Water Frame Directive (WFD) for these specific water bodies. Under this scope, water and sediment samples were collected from five sites within the Port of Aveiro, Portugal. According to the physical and chemical parameters that were analyzed (i.e., metals, total organic carbon, polychlorinated biphenyls and polycyclic aromatic hydrocarbons), the sediments were not considered at risk based on European sediment quality laws. However, the bioassays that were performed on the sediment samples (Microtox®) and the standardized acute toxicity test using the marine rotifer, Brachionus plicatilis, on sediment elutriates revealed higher toxicity levels. The use of bioassays to assess sediment quality clearly complements more conservative approaches and highlights current gaps within the WFD. The approach presented here can be easily transferred to other port areas for more reliable water quality management.
Afficher plus [+] Moins [-]An ecotoxicological analysis of the sediment quality in a European Atlantic harbor emphasizes the current limitations of the Water Framework Directive Texte intégral
2013
Gonçalves, Sandra F. | Calado, Ricardo | Gomes, Newton C. M. | Soares, Amadeu M. V. M. | Loureiro, Susana
The "PortoNovo" project was developed to standardize the methodologies for water quality management in the port areas of coastal Atlantic regions to improve the Water Frame Directive (WFD) for these specific water bodies. Under this scope, water and sediment samples were collected from five sites within the Port of Aveiro, Portugal. According to the physical and chemical parameters that were analyzed (i.e., metals, total organic carbon, polychlorinated biphenyls and polycyclic aromatic hydrocarbons), the sediments were not considered at risk based on European sediment quality laws. However, the bioassays that were performed on the sediment samples (Microtox®) and the standardized acute toxicity test using the marine rotifer, Brachionus plicatilis, on sediment elutriates revealed higher toxicity levels. The use of bioassays to assess sediment quality clearly complements more conservative approaches and highlights current gaps within the WFD. The approach presented here can be easily transferred to other port areas for more reliable water quality management.
Afficher plus [+] Moins [-]Sources, fluxes and risk of organic micropollutants to the Cantabrian Sea (Spain) Texte intégral
2013
Sánchez-Avila, Juan | Vicente, Joana | Echavarri-Erasun, Beatriz | Porte, Cinta | Tauler, Romà | Lacorte, Silvia
The sources, distribution and risk of 51 organic micropollutants (OMPs) in the Cantabrian coastal environment (NW Spain) were evaluated. Gas chromatography coupled to tandem mass spectrometry was used to determine polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorinated pesticides, polybrominated diphenyl ethers, phthalates esters, bisphenol A and alkylphenols. 45 OMPs were detected in coastal/estuarine waters. Wastewater treatment plant effluents and emissary discharges were identified as the main sources of contamination. The accumulation of OMPs in sediments and the bioaccumulation in 21days caged mussels were also assessed. Chemical results were combined with the “Combined Monitoring-based and Modeling-based Priority Setting Scheme” COMMPS procedure for risk assessment analysis. Finally, the chemical status of the different sampling locations was estimated using site risk indexes. Those indexes can be conveniently displayed in quality geographical maps and are considered a valuable tool for the environmental management and risk assessment of the region under study.
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