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Fish discards management: Pollution levels and best available removal techniques
2012
Antelo, Luis T. | Lopes, Carla | Franco-Uría, Amaya | Alonso, Antonio A.
Fish discards and by-catch issues are highly topical subjects that are permanently under a social focus. Two main approaches are being considered to address this discard problem: reducing the by-catch and increasing by-catch utilization. Interest in increased by-catch valorization may arise from a greater demand for fish products, such as the development of new markets for previously discarded species, the use of low-value specimens for aquaculture or the creation of value-added fish products for the food, pharmaceutical or cosmetic industries. However, contaminants present in fish discards may be transferred to their valorized products, leading to possible long-term bioaccumulation and subsequent adverse health effects. In this valorization framework, the aim is to promote responsible and sustainable management of marine resources. The pollutant levels in catches from European fisheries and the best available decontamination techniques for marine valorized discards/by-products are compiled and analyzed in this work.
Afficher plus [+] Moins [-]Twenty years of Belgian North Sea aerial surveillance: A quantitative analysis of results confirms effectiveness of international oil pollution legislation
2012
Lagring, Ruth | Degraer, Steven | de Montpellier, Géraldine | Jacques, Thierry | Van Roy, Ward | Schallier, Ronny
Over the years many policy measures have been taken to prevent illegal oil discharges from ships, like the MARPOL 73/78 Convention (1983) and the Bonn Agreement (1969/1983). However, the number of discharges remained high, leading to chronic oiling of seabirds and sensitive coastlines, therefore further measures were taken. The aim of this study is to quantify the effectiveness of two key legislative regulations: the IMO-designation of the North Sea as MARPOL Special Area which took effect in 1999, and the adoption of the EU Directive on Port Reception Facilities in 2000. Under study is the heavily navigated Belgian Surveillance Area, monitored since 1991, characterised by shallow waters with ecologically important sandbanks. The aerial surveillance data from 1991 to 2010 show a stepwise decrease in ship-source oil pollution. Three time periods can be distinguished with two turning points coinciding with the actual implementation of these key legislative measures, confirming their effectiveness.
Afficher plus [+] Moins [-]Asia–Pacific mussel watch for emerging pollutants: Distribution of synthetic musks and benzotriazole UV stabilizers in Asian and US coastal waters
2012
Nakata, Haruhiko | Shinohara, Ryu-Ichi | Nakazawa, Yusuke | Isobe, Tomohiko | Sudaryanto, Agus | Subramanian, Annamalai | Tanabe, Shinsuke | Zakaria, Mohamad Pauzi | Zheng, Gene J. | Lam, Paul K.S. | Kim, Eun-Young | Min, Byung-Yoon | We, Sung-Ug | Viet, Pham Hung | Dūc Sʹāṅ Tānā, | Prudente, Maricar | Frank, Donnell | Lauenstein, G. G. | Kannan, Kurunthachalam
We analyzed 68 green and blue mussels collected from Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Vietnam and the USA during 2003 and 2007, to elucidate the occurrence and widespread distributions of emerging pollutants, synthetic musks and benzotriazole UV stabilizers (BUVSs) in Asia–Pacific coastal waters. Synthetic musks and BUVSs were detected in mussels from all countries, suggesting their ubiquitous contamination and widespread distribution. High concentrations of musks and BUVSs were detected in mussels from Japan and Korea, where the levels were comparable or greater than those of PCBs, DDTs and PBDEs. Significant correlations were found between the concentrations of HHCB and AHTN, and also between the concentrations of UV-327 and UV-328, which suggest similar sources and compositions of these compounds in commercial and industrial products. To our knowledge, this is the first study of large-scale monitoring of synthetic musks and BUVSs in Asia–Pacific coastal waters.
Afficher plus [+] Moins [-]Seasonal variation of polycyclic aromatic hydrocarbons concentrations in urban streams at Niterói City, RJ, Brazil
2012
Ribeiro, Angelo Morgado | da Rocha, Camila Coimbra Martins | Franco, Caroline Fernandes Jaegger | Fontana, Luiz Francisco | Pereira Netto, Annibal D.
Polycyclic aromatic hydrocarbons (PAHs) were determined in water samples collected in two streams and a lake located at Niteroi City, Rio de Janeiro State, Brazil between October 2008 and September 2009. Samples were extracted using liquid–liquid extraction and analyzed using high performance liquid chromatography with fluorescence detection. The limits of quantification were sufficiently low to accomplish PAH determination below the maximum concentration levels established by the Brazilian (50ng/L) and USEPA legislations, with recoveries larger than 81.6%. Phenanthrene, fluoranthene, pyrene and benz[a]anthracene predominated among PAHs. Total concentrations of PAHs were well correlated with rainfall indicating a possible role of runoff to local pollution of water by PAHs and showed a seasonal variation in wet and dry seasons. Our results highlight the contribution of the widespread streams located around Guanabara Bay to the PAH burden found in its waters.
Afficher plus [+] Moins [-]Effects of prolonged entanglement in discarded fishing gear with substantive biofouling on the health and behavior of an adult shortfin mako shark, Isurus oxyrinchus
2012
Wegner, Nicholas C. | Cartamil, Daniel P.
A mature male shortfin mako, Isurus oxyrinchus, was captured with a three-strand twisted natural fiber rope wrapped around the body causing deep abrasions, scoliosis of the back, and undernourishment. Fifty-two pelagic peduculate barnacles from four species were found fouling on the rope. Assuming larval settlement occurred following entanglement, barnacle growth-rate data suggest the rope had been around the shark for at least 150days. However, the onset of severe scoliosis (likely linked to the increased constriction of the rope with growth and the added drag induced by biofouling) indicates that this rope may have been in place much longer. Following removal of the rope, a pop-up satellite archival tag was attached to the shark to assess post-release health. The resulting 54days of tag deployment data show that despite its injuries, the shark survived, and following an initial stress period, exhibited movement patterns characteristic of healthy makos.
Afficher plus [+] Moins [-]Radionuclide monitoring in molluscs inhabiting intertidal region near a nuclear installation, Gulf of Mannar, India
2012
Feroz Khan, M. | Godwin Wesley, S.
Protection of non-human biota from ionizing contaminants, especially in the vicinity of nuclear installations is a very important aspect for nuclear engineers and ecologists. In this view, a baseline data on the activity concentration of ²¹⁰Po and ²¹⁰Pb were quantified in different tissues of molluscs inhabiting the intertidal region along the coast of Kudankulam. The activity concentration was noticed higher in the organs associated with digestion and metabolism. Filter feeding bivalve molluscs registered the maximum activity of ²¹⁰Po in their whole body compared to grazing gastropods. ²¹⁰Po:²¹⁰Pb ratio was calculated to be greater than unity in most of the analysed tissues. The ecological sensitivity of molluscs to the radiation exposure and the safeness of the environment was analysed by calculating the external and internal dose rate. The hazard quotient for molluscs was lesser than the global bench mark dose rate of 10μGyh–¹.
Afficher plus [+] Moins [-]Real-time PCR and NASBA for rapid and sensitive detection of Vibrio cholerae in ballast water
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.
Afficher plus [+] Moins [-]Evaluation of diffusive gradients in thin-films (DGTs) as a monitoring tool for the assessment of the chemical status of transitional waters within the Water Framework Directive
2012
Montero, N. | Belzunce-Segarra, M.J. | Gonzalez, J.-L. | Larreta, J. | Franco, J.
In this contribution, the potential use of diffusive gradients in thin-films (DGTs) for the chemical evaluation of transitional water bodies within the Water Framework Directive (WFD) has been studied. The water metal concentration has been evaluated in 13 estuaries in the southeastern Bay of Biscay. The DGTs were deployed in triplicate at two stations in each estuary, delimiting the tidal influence. The DGT results were in the ranges of 2–1570ngL⁻¹ for cadmium, 66–515ngL⁻¹ for copper, 30–3650ngL⁻¹ for nickel and 0.8–95.5μgL⁻¹ for zinc. The DGTs provided reliable average labile metal concentrations in highly dynamic systems that were comparable with DGT measurements in coastal and estuarine waters worldwide. In addition, it was possible to discriminate those estuaries more susceptible to environmental impacts, being consistent with the historical contamination of each estuary. Based on the obtained results, a sampling strategy for the monitoring of transitional water bodies using DGTs is proposed.
Afficher plus [+] Moins [-]Chemical composition and acute toxicity in the water after in situ burning – A laboratory experiment
2012
Faksness, Liv-Guri | Hansen, Bjørn Henrik | Altin, Dag | Brandvik, Per Johan
The chemical composition and toxicity of a water soluble fraction (WSF) of oil versus the underlying water after in situ burning (ISB), has been studied in a laboratory experiment. A system for allowing water sampling after ISB was developed. Seawater samples and oil were collected prior to and immediately after ISB, and chemical analysis was conducted. The chemical characterization of the water showed that the disappearance of water soluble oil components during ISB was insignificant. Acute toxicity tests with the marine copepod Calanus finmarchicus and Microtox® bioassay was performed to establish LC₅₀/EC₅₀ values of the water. The results were compared with regular WAF systems with unburned weathered oil, and indicated no increase in toxicity in the underlying water after ISB.
Afficher plus [+] Moins [-]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
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.
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