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Effects of chlorpyrifos on cholinesterase activity and stress markers in the tropical reef fish Acanthochromis polyacanthus Полный текст
2012
Botté, E.S. | Jerry, D.R. | Codi King, S. | Smith-Keune, C. | Negri, A.P.
Tropical coastal ecosystems, including the Great Barrier Reef (GBR) of Australia are increasingly threatened by pollution; yet few studies have investigated the sensitivity of GBR species to these pollutants. Here we exposed juveniles of the tropical reef fish Acanthochromis polyacanthus (spiny damselfish) to three concentrations of the insecticide chlorpyrifos (CPF) and measured (i) muscle cholinesterase (ChE) activity; (ii) hepatic glutathione-S-transferase (GST) activity; and (iii) coenzyme Q (CoQ) redox balance, after 6h and 96h of exposure. After 96h, muscle ChE activity was significantly inhibited by 26%, 49% and 53% when fish were exposed to 1, 10 or 100μg/L CPF, respectively. Muscle ChE characterization revealed three types of ChEs, including two atypical forms. Hepatic CoQ antioxidant form significantly increased at 10μg/L after 6h of exposure, potentially demonstrating an early response to CPF-induced oxidative stress in liver. Hepatic GST was not affected by CPF exposure.
Показать больше [+] Меньше [-]Antibiotic resistant pathogens versus human impacts: A study from three eco-regions of the Chennai coast, southern India Полный текст
2012
Vignesh, Sivanandham | Muthukumar, Krishnan | Arthur James, Rathinam
We assessed the occurrence of pollution indicators and antibiotic resistant bacterial isolates from water and sediment samples of three different eco-regions of the Chennai coast between March – May of 2010. Total of 960 bacterial strains belonging to four genera were isolated which show the highest frequencies of resistance to vancomycin (53.6%) and penicillin (52.6%) (except Enterococcus sp., which is highly resistant to erythromycin) and lowest frequencies of resistance to chloramphenicol (3.43%), ciprofloxacin (3.95%), gentamicin (4.68%), and tetracycline (6.97%). The E. coli, Vibrio sp., Salmonella sp. and Enterococcus sp. show high frequency of resistance to 2–5 antibacterials of 60.4%, 45.83%, 69.16% and 46.6%, respectively. High pollution indices (PI – 6.66–14.06) and antibiotic resistance indices (ARI – 0.29–0.343) indicate that the coastal environment is highly exposed to antibiotic sources that suggesting to avoid direct contact.
Показать больше [+] Меньше [-]Sponges as sentinels: Patterns of spatial and intra-individual variation in trace metal concentration Полный текст
2012
de Mestre, C. | Maher, W. | Roberts, D. | Broad, A. | Krikowa, F. | Davis, A.R.
If sponges are to be effective biomonitors we require a better understanding of the spatial scales over which metals vary in these organisms. We determined how concentration of Cd, Zn, Cu, Pb, Hg and Se varied over four spatial scales for two common estuarine sponge species in the Sydney region. We examined variability with a fully nested sampling design; between coastal lakes, within coastal lakes, between sponges and within sponges. Calculation of variance components confirmed that ‘within-sponge’ variation in Cd, Zn, Cu, Pb and Se concentrations were low (1–14%) relative to the two largest spatial scales (49–98%) examined. In contrast, Hg concentrations exhibited marked variability ‘between-sponges’ and were below detection at one location. There was little evidence that sponge size was a good predictor of metal concentration. Taken together, these outcomes confirm that fragments of these sponges could be successfully transplanted and therefore show promise as biomonitors of metal contamination.
Показать больше [+] Меньше [-]At-sea detection of derelict fishing gear in the North Pacific: An overview Полный текст
2012
Morishige, Carey | McElwee, Kris
There are numerous known impacts of derelict fishing gear (DFG) to marine ecosystems and safe navigation around the world. To mitigate these impacts, the preemptive detection and removal of DFG at sea are being pursued. This special issue focuses on the North Pacific Ocean because of historic and ongoing research on DFG in the area, particularly as it relates to the Hawaiian Archipelago. In order to develop an effective detection strategy, information and expertise from three disciplines must be integrated: marine debris, oceanography, and remote sensing technology. Building upon results and discussions during a workshop held in December 2008, this special issue provides both results of original research and review papers, pursuing each discipline as it relates to DFG and outlining a multi-faceted strategy to effectively detect DFG at sea. This strategy serves as a roadmap, taking us closer to realizing the goal of detecting and removing DFG at sea.
Показать больше [+] Меньше [-]Status of marine pollution research in South Africa (1960–present) Полный текст
2012
Wepener, V. | Degger, N.
The published literature on marine pollution monitoring research in South Africa from 1960 to present was evaluated. There has been a general decline in the number of papers from the 1980s and this can be linked to the absence of a marine pollution monitoring programme in South Africa. General trends observed were that contaminant exposure monitoring of metals predominates the research conducted to date. Monitoring results indicate that there has been a general decrease in metal concentrations in South African coastal waters and concentrations of metals and most organics in mussels are lower than in other industrialised nations. This is reflected in the general pristine nature and high biodiversity of the South African coastline. The establishment of a national marine pollution monitoring framework would stimulate marine pollution research.
Показать больше [+] Меньше [-]Real-time PCR and NASBA for rapid and sensitive detection of Vibrio cholerae in ballast water Полный текст
2012
Fykse, Else M. | Nilsen, Trine | Nielsen, Agnete Dessen | Tryland, Ingun | Delacroix, Stephanie | Blatny, Janet M.
Transport of ballast water is one major factor in the transmission of aquatic organisms, including pathogenic bacteria. The IMO-guidelines of the Convention for the Control and Management of Ships’ Ballast Water and Sediments, states that ships are to discharge <1CFU per 100ml ballast water of toxigenic Vibrio cholerae, emphasizing the need to establish test methods. To our knowledge, there are no methods sensitive and rapid enough available for cholera surveillance of ballast water. In this study real-time PCR and NASBA methods have been evaluated to specifically detect 1CFU/100ml of V. cholerae in ballast water. Ballast water samples spiked with V. cholerae cells were filtered and enriched in alkaline peptone water before PCR or NASBA detection. The entire method, including sample preparation and analysis was performed within 7h, and has the potential to be used for analysis of ballast water for inspection and enforcement control.
Показать больше [+] Меньше [-]Levels and spatial distribution of trace elements in macroalgae species from the Todos os Santos Bay, Bahia, Brazil Полный текст
2012
Brito, Geysa B. | de Souza, Thaís L. | Bressy, Fernanda C. | Moura, Carlos W.N. | Korn, Maria Graças A.
Concentrations of elements (As, Ba, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, V, and Zn) were determined in ten species of macroalgae collected from six sites in the Todos os Santos Bay, Brazil, between May and July of 2010. An optimized microwave-assisted digestion procedure was used to digest the samples. The elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). A wide range of metal concentrations were observed between the species analysed. Somewhat higher concentrations of Cd (5.99μgg⁻¹), Co (372μgg⁻¹), Mn (640μgg⁻¹), Ni (17.2μgg⁻¹) and Zn (51.4μgg⁻¹) were found in the brown macroalgae species Padina spp., whereas elements, such as As (19.7μgg⁻¹) and Pb (8.27μgg⁻¹), were mainly concentrated in the species Sargassum spp. and Bostrychia montagnei, respectively. Statistical analyses (ANOVA) of the Padina data showed significant inter-site differences for all metals examined except nickel.
Показать больше [+] Меньше [-]Spatial and temporal variations in nitrogen and phosphorous nutrients in the Yangtze River Estuary Полный текст
2012
Chen, Yaxin | Liu, Ruimin | Sun, Chengchun | Zhang, Peipei | Feng, Chenghong | Shen, Zhenyao
Based on spatial interpolation data from 2003 to 2010, combined with almost 30years of nitrogen and phosphorus pollutant data, this research analyzed the variations in total nitrogen (TN), nitrate nitrogen (NO₃-N), total phosphorus (TP) and phosphate-P (PO₄-P) in the Yangtze River Estuary (YRE). On the annual and seasonal timescales, nitrogen and phosphorus concentrations exhibited increasing trends overall, and the fluctuations in the concentrations of TN, TP and PO₄-P significantly increased during the last three decades, especially after 2003, because of the more prevalent human activities and nonpoint sources in the area. Specifically, a high-concentration area of TN was found downstream of the North Branch of the YRE. Considering the spatial distribution of the nutrients, combined with a tidal flood current and a time span of 7years, the TN maximum increased from approximately 3.07mg/L to 4.48mg/L. The TP maximum also rose from approximately 0.25mg/L to 0.34mg/L because of a high-concentration area of TP in the South Branch of the YRE due to the confluence with the Huangpu River. Additionally, there was an expansion of high-concentration areas of TN (⩾3.0mg/L) and of TP (⩾0.20mg/L).
Показать больше [+] Меньше [-]Modelling the environmental behaviour of pollutants in Algeciras Bay (south Spain) Полный текст
2012
Periáñez, R.
An environmental study of Algeciras Bay is carried out through numerical modelling. First, a 2D barotropic model is applied to calculate tides and mean circulation. Results of this model are used by a sediment transport model which provides suspended matter concentrations and sedimentation rates in the Bay. It includes three particle classes. An effective diffusion coefficient has been calibrated simulating temperature distribution inside the Bay. An additional validation is obtained from an independent nitrate dispersion simulation. Then heavy metal dispersion patterns are investigated using a model which includes water–sediment metal interactions and uses the outputs of the hydrodynamic and sediment transport models. The metal transport model has been applied to simulate the dispersion of Zn, Cu and Ni. Results from the hydrodynamic, sediment and metal transport models have been compared with measurements. Model results also indicate that transport inside the Bay is relatively weak. Numerical experiments have been carried out to determine flushing times for conservative and non-conservative pollutants. Flushing time is about 20days for a conservative tracer, and this value is mainly due to the M₂ residual current. Tides are not effective in removing pollutants.
Показать больше [+] Меньше [-]Evaluation of the presence of major anionic surfactants in marine sediments Полный текст
2012
Cantarero, S. | Camino-Sánchez, F.J. | Zafra-Gómez, A. | Ballesteros, O. | Navalón, A. | Vílchez, J.L. | Verge, C. | Reis, M.S. | Saraiva, P.M.
The contamination of aquatic environments has become the focus of increasing regulation and public concern due to their potential and unknown negative effects on the ecosystems. The present work develops a monitoring and statistical study, based on the analysis of variance test (ANOVA) and the multivariable analysis, both for insoluble soap and LAS in order to compare the behavior of different anionic surfactants in this environmental compartment. First, a novel and successfully validated methodology to analyze insoluble soap in these samples is developed. The matrix effect and the comparison of different extraction techniques were also performed. The optimized analytical methodologies were applied to 48 representative samples collected from the Almeria Coast (Spain) and then a statistical analysis to correlate anionic surfactant concentration and several variables associated with marine sediment samples was also developed. The results obtained showed relevant conclusions related to the environmental behavior of anionic surfactants in marine sediments.
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