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Rapid quantification of infectious enterovirus from surface water in Bohai Bay, China using an integrated cell culture-qPCR assay
2011
Ming, Hong-Xia | Zhu, Lin | Zhang, Yuan
To rapidly quantify infectious enteroviruses polluting the coastal seawaters, a newly developed integrated cell culture and reverse transcription quantitative PCR (ICC-RT-qPCR) assay was used to identify the contamination by enteroviruses in winter seawater samples of Bohai Bay, Tianjin, China. The gene copies of enteroviral 5′UTRs correlated to the initial inoculum numbers across the concentration range of 0.05–500PFUmL⁻¹ (correlation coefficient (R²) was 0.9667). ICC-qPCR revealed that five of seven samples (70.4%) were positive for infectious enteroviruses. The concentration of enteroviruses was estimated at 0.2–21PFUL⁻¹. The result demonstrated that the contamination of enteroviruses in this coastal area may constitute a potential public health risk. This study established a practical assay for widespread monitoring studies of aquatic environments for viral contamination and provided meaningful data for human waterborne viral risk assessment.
Afficher plus [+] Moins [-]Antifouling activity of commercial biocides vs. natural and natural-derived products assessed by marine bacteria adhesion bioassay
2011
Camps, Mercedes | Briand, Jean-François | Guentas-Dombrowsky, Linda | Culioli, Gérald | Bazire, Alexis | Blache, Yves
Biofilm formation is a key step during marine biofouling, the natural colonization of immersed substrata, leading to major economic and ecological consequences. Consequently, bacteria have been used for the screening of new non-toxic antifoulants: the adhesion of five strains isolated on three French locations was monitored using a fluorescence-based assay and toxicity was also evaluated. Nine biocides including commercial, natural and natural-derived products were tested. The commercial antifoulants, TBTO and Sea Nine showed low EC₅₀ but high toxicity. The non-commercial products TFA-Z showed significant anti-adhesion activities and appeared to be non-toxic, suggesting a specific anti-adhesion mechanism. In addition, the strains could be classified depending on their sensitivity to the molecules used even if strain sensitivity also depended on the molecules tested. In conclusion, TFA-Z would be a promising candidate as non-toxic antifoulant and our results strengthen the need to perform antifouling bioassays with a panel of strains showing different response profiles.
Afficher plus [+] Moins [-]Acute toxicities of five commonly used antifouling booster biocides to selected subtropical and cosmopolitan marine species
2011
Bao, Vivien W.W. | Leung, Kenneth M.Y. | Qiu, Jian-Wen | Lam, Michael H.W.
Since 1990s, various booster biocides have been increasingly used as substitutes of organotins. However, knowledge about their toxicities on tropical/sub-tropical marine species is significantly lacking. This study comprehensively investigated the acute toxicities of copper, tributyltin (TBT), and five commonly used booster biocides including Irgarol, diuron, zinc pyrithione (ZnPT), copper pyrithione (CuPT) and chlorothalonil on the growth or survival of 12 marine species in which eight of them are native species of subtropical Hong Kong. We found that Irgarol was more toxic than TBT on the growth of autotrophic species. The toxicity of CuPT was comparable to that of TBT on almost all test species, while it showed higher toxicity than TBT on medaka fish larvae. As the usage of these biocides is expected to further increase worldwide, accurate assessments of their ecological risks are required for better informed decision on their management. This study provided useful datasets for such purposes.
Afficher plus [+] Moins [-]SWASV speciation of Cd, Pb and Cu for the determination of seawater contamination in the area of the Nicole shipwreck (Ancona coast, Central Adriatic Sea)
2011
Annibaldi, Anna | Illuminati, Silvia | Truzzi, Cristina | Scarponi, Giuseppe
The study reports for the first time on the heavy metal contamination of the waters surrounding a shipwreck lying on the sea floor. Square wave anodic stripping voltammetry has been used for a survey of the total and dissolved Cd, Pb and Cu contents of the seawater at the site of the sinking of the Nicole M/V (Coastal Adriatic Sea, Italy). Results show that the hulk has a considerable impact as regards all three metals in the bottom water, especially for the particulate fraction concentrations, which increased by factors of ∼9 (Cd), ∼3 (Pb) and ∼5 (Cu). The contaminated plume extended downstream for about 2miles. Much lower contamination was observed for dissolved bottom concentrations; nevertheless Pb (0.56±0.03nmol/L) is higher than the Italian legal limits established for 2015 and Cd (0.23±0.03nmol/L) is very close the limit of Cd will be exceeded if the hulk is not removed.
Afficher plus [+] Moins [-]Seasonal and spatial variability of water quality parameters in the Port of Genoa, Italy, from 2000 to 2007
2011
Ruggieri, N. | Castellano, M. | Capello, M. | Maggi, S. | Povero, P.
This paper presents the results of the statistical analysis of a set of physico-chemical and biological water quality parameters, monthly collected from 2000 to 2007 in the Genoa Harbour area (Ligurian Sea). We applied multivariate methods, such as principal component analysis (PCA) and dynamic factor analysis (DFA) for investigating the spatial and temporal variability and for providing important background information on pollution problems in the region. PCA evidenced the role of the sewage and river discharges and of the exchanges with the open sea in determining the harbour water quality. DFA was used to estimate underlying common trends in the time series. The DFA results partly show a general improvement of water quality over the 8-years period. However, in other areas, we found inter-annual variations but no significant multi-annual trend. Furthermore, we included meteorological variables in our statistical analyses because of their potential influence on the water quality parameters. These natural forcings explain part of the variability in water quality parameters that are superimposed on the dominating anthropogenic pollution factors.
Afficher plus [+] Moins [-]Microplastics in the marine environment
2011
Andrady, A. L. (Anthony L.)
This review discusses the mechanisms of generation and potential impacts of microplastics in the ocean environment. Weathering degradation of plastics on the beaches results in their surface embrittlement and microcracking, yielding microparticles that are carried into water by wind or wave action. Unlike inorganic fines present in sea water, microplastics concentrate persistent organic pollutants (POPs) by partition. The relevant distribution coefficients for common POPs are several orders of magnitude in favour of the plastic medium. Consequently, the microparticles laden with high levels of POPs can be ingested by marine biota. Bioavailability and the efficiency of transfer of the ingested POPs across trophic levels are not known and the potential damage posed by these to the marine ecosystem has yet to be quantified and modelled. Given the increasing levels of plastic pollution of the oceans it is important to better understand the impact of microplastics in the ocean food web.
Afficher plus [+] Moins [-]Trace metals in harbour and slipway sediments from the island of Malta, central Mediterranean
2011
Huntingford, Emily J. | Turner, Andrew
Sediment samples collected from large harbours and public slipways on the island of Malta have been analysed for geochemically important metals (Al, Ca, Fe, Mn) and contaminant metals (As, Cd, Co, Cr, Cu, Ni, Pb, Sn, Zn) following fractionation (<63μm) and digestion in aqua regia. Absolute and Al-normalised concentrations of contaminant metals exhibited relatively little dispersion both among different samples from the same location and between samples from different locations, notable exceptions including lower concentrations of Cr and Sn on the slipways than in the harbours. Sources of contaminant metals are attributed to diffuse and specific waste inputs from urban surroundings and boating and shipping activities. Overall, concentrations are similar to those reported for other large harbours in urban settings where equivalent sample fractionation-digestion has been performed. Relative to various sediment quality guidelines, Pb is predicted to exert the greatest threat to the marine environment of Malta.
Afficher plus [+] Moins [-]Sedimentation on the cold-water coral Lophelia pertusa: Cleaning efficiency from natural sediments and drill cuttings
2011
Larsson, Ann I. | Purser, Autun
Anthropogenic threats to cold-water coral reefs are trawling and hydrocarbon drilling, with both activities causing increased levels of suspended particles. The efficiency of Lophelia pertusa in rejecting local sediments and drill cuttings from the coral surface was evaluated and found not to differ between sediment types. Further results showed that the coral efficiently removed deposited material even after repeated exposures, indicating an efficient cleaning mechanism. In an experiment focusing on burial, fine-fraction drill cuttings were deposited on corals over time. Drill cutting covered coral area increased with repeated depositions, with accumulation mainly occurring on and adjacent to regions of the coral skeleton lacking tissue cover. Tissue was smothered and polyp mortality occurred where polyps became wholly covered by material. Burial of coral by drill cuttings to the current threshold level used in environmental risk assessment models by the offshore industry (6.3mm) may result in damage to L. pertusa colonies.
Afficher plus [+] Moins [-]ANN application for prediction of atmospheric nitrogen deposition to aquatic ecosystems
2011
Palani, Sundarambal | Tkalich, Pavel | Balasubramanian, Rajasekhar | Palanichamy, Jegathambal
The occurrences of increased atmospheric nitrogen deposition (ADN) in Southeast Asia during smoke haze episodes have undesired consequences on receiving aquatic ecosystems. A successful prediction of episodic ADN will allow a quantitative understanding of its possible impacts. In this study, an artificial neural network (ANN) model is used to estimate atmospheric deposition of total nitrogen (TN) and organic nitrogen (ON) concentrations to coastal aquatic ecosystems. The selected model input variables were nitrogen species from atmospheric deposition, Total Suspended Particulates, Pollutant Standards Index and meteorological parameters. ANN models predictions were also compared with multiple linear regression model having the same inputs and output. ANN model performance was found relatively more accurate in its predictions and adequate even for high-concentration events with acceptable minimum error. The developed ANN model can be used as a forecasting tool to complement the current TN and ON analysis within the atmospheric deposition-monitoring program in the region.
Afficher plus [+] Moins [-]Persistence profile of polyaromatic hydrocarbons in shallow and deep Gulf waters and sediments: Effect of water temperature and sediment–water partitioning characteristics
2011
Tansel, B. | Fuentes, C. | Sánchez, M. | Predoi, K. | Acevedo, M.
Persistence profiles of selected polyaromatic hydrocarbons (PAHs) were analyzed depending on temperature variations in the water column and water–sediment interactions in the Gulf of Mexico. The PAHs studied include anthracene, fluoranthene, pyrene, and chrysene. The half-lives of PAHs in the deep waters (over 1000m) are about twice as long as those in the shallow areas (100–150m), and almost 2.5 times as long as those in the top layer (0–10m) of the water column. The half-lives of the PAHs in the sediments are significantly longer. Among the PAHs studied, chrysene is the most persistent in the water column, and pyrene is the most persistent in the sediments. The half-life of chrysene in the shallow and deep waters is over 2.5 and about 5years, respectively. For pyrene, the half-life in the shallow and deep sediments is about 9 and 16years, respectively.
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