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Incorporation of in situ exposure and biomarkers response in clams Ruditapes philippinarum for assessment of metal pollution in coastal areas from the Maluan Bay of China Full text
2012
Wang, Zaosheng | Yan, Changzhou | Vulpe, Chris D. | Yan, Yijun | Chi, Qiaoqiao
The clams Ruditapes philippinarum were used to assess the impact of metal contaminants when transplanted to seven study sites along the Maluan Bay (China). Metal concentrations in digestive gland tissues of clams after 7-day in situ cage exposure were determined in conjunction with antioxidant enzyme activities. The results showed the importance of specific antioxidant biomarkers to assess complex pollutant mixtures and their good correlations to the pollutant compositions of deployment sites. Multivariate analysis indicated causal relationship between the chemicals at each study site and the biochemical “response” of the caged clams at these sites and demonstrated the potential presence of two different contaminant sources. This study suggested that the incorporation of tissue residue analysis with biomarkers response in caged clams together with factor analysis can be a useful biomonitoring tool for the identification of causal toxic pollutants and the assessment of complex metal pollutions in marine coastal environment.
Show more [+] Less [-]The effect of mangrove reforestation on the accumulation of PCBs in sediment from different habitats in Guangdong, China Full text
2012
Zhao, Bo | Zhou, Yan-wu | Chen, Gui-zhu
To investigate the influence of mangrove reforestation on the accumulation of PCBs, the concentrations and homologue patterns of polychlorinated biphenyls in surface sediments from different mangrove forests and their adjacent mud flats in Guangdong Province were determined. The total PCB concentrations in the sediments ranged from 3.03 to 46.62ngg⁻¹ (dry weight). Differences in the accumulation and distribution of PCBs were found between the mangrove sites and the mud flats. Furthermore, the natural forests and restored mangrove forests of native species showed slight PCB contamination, whereas the exotic species Sonneratia apetala exacerbated the PCB pollution at certain sites. It was suggested that the native mangrove species Kandelia candel and Aegiceras corniculatum could represent good choices for the phytoremediation of PCB contamination.
Show more [+] Less [-]Effects of chlorpyrifos on cholinesterase activity and stress markers in the tropical reef fish Acanthochromis polyacanthus Full text
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.
Show more [+] Less [-]Antibiotic resistant pathogens versus human impacts: A study from three eco-regions of the Chennai coast, southern India Full text
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.
Show more [+] Less [-]Sponges as sentinels: Patterns of spatial and intra-individual variation in trace metal concentration Full text
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.
Show more [+] Less [-]At-sea detection of derelict fishing gear in the North Pacific: An overview Full text
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.
Show more [+] Less [-]Status of marine pollution research in South Africa (1960–present) Full text
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.
Show more [+] Less [-]Real-time PCR and NASBA for rapid and sensitive detection of Vibrio cholerae in ballast water Full text
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.
Show more [+] Less [-]Levels and spatial distribution of trace elements in macroalgae species from the Todos os Santos Bay, Bahia, Brazil Full text
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.
Show more [+] Less [-]Spatial and temporal variations in nitrogen and phosphorous nutrients in the Yangtze River Estuary Full text
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).
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