Refine search
Results 581-590 of 1,309
Occurrence of priority pollutants in WWTP effluents and Mediterranean coastal waters of Spain
2011
Martí, N. | Aguado, D. | Segovia-Martínez, L. | Bouzas, A. | Seco, A.
A comprehensive study aimed at evaluating the occurrence, significance of concentrations and spatial distribution of priority pollutants (PPs) along the Comunidad Valenciana coastal waters (Spain) was carried out in order to fulfil the European Water Framework Directive (WFD). Additionally, PP concentrations were also analysed in the effluent of 28 WWTPs distributed along the studied area. In coastal waters 36 organic pollutants of the 71 analysed, including 26 PPs were detected although many of them with low frequency of occurrence. Only 13 compounds, which belong to four different classes (VOCs, organochlorinated pesticides, phthalates and tributyltin compounds (TBT)) showed a frequency of occurrence above 20% in coastal waters. In the results obtained until now, octylphenol, pentachlorobenzene, DEHP and TBT exceeded the annual average concentration (EQS-AAC), and only TBT surpassed the maximum allowable concentration (EQS-MAC). The most frequent contaminants determined in coastal waters were also present in WWTP effluents.
Show more [+] Less [-]Risk mapping for sensitive species to underwater anthropogenic sound emissions: Model development and validation in two Mediterranean areas
2011
Azzellino, A. | Lanfredi, C. | D’Amico, A. | Pavan, G. | Podestà, M. | Haun, J.
Recent observations of cetacean mass strandings, coincident with anthropogenic sounds emissions, have raised concerns on the potential environmental impact of underwater noise. Cuvier’s beaked whale (Ziphius cavirostris) was reported in all the cited stranding events. Within the NATO Marine Mammal Risk Mitigation project (MMRM), multiple interdisciplinary sea trials have been conducted in the Mediterranean Sea with the objective of developing tools and procedures to mitigate the impact of underwater sound emissions. During these cruises, visual observations, passive acoustic detections and environmental data were collected. The aim of this study was to evaluate “a priori” predictions of Cuvier’s beaked whale presence in the Alboran Sea, using models developed in the Ligurian Sea that employ bathymetric and chlorophyll features as predictors. The accuracy of these predictions was found adequate and elements are given to account for the uncertainties associated to the use of models developed in areas different from their calibration site.
Show more [+] Less [-]Early warning indicators for river nutrient and sediment loads in tropical seagrass beds: A benchmark from a near-pristine archipelago in Indonesia
2011
van Katwijk, M.M. | van der Welle, M.E.W. | Lucassen, E.C.H.E.T. | Vonk, J.A. | Christianen, M.J.A. | Kiswara, W. | Inayat al Hakim, I. | Arifin, A. | Bouma, T.J. | Roelofs, J.G.M. | Lamers, L.P.M.
In remote, tropical areas human influences increase, potentially threatening pristine seagrass systems. We aim (i) to provide a bench-mark for a near-pristine seagrass system in an archipelago in East Kalimantan, by quantifying a large spectrum of abiotic and biotic properties in seagrass meadows and (ii) to identify early warning indicators for river sediment and nutrient loading, by comparing the seagrass meadow properties over a gradient with varying river influence. Abiotic properties of water column, pore water and sediment were less suitable indicators for increased sediment and nutrient loading than seagrass properties. Seagrass meadows strongly responded to higher sediment and nutrient loads and proximity to the coast by decreasing seagrass cover, standing stock, number of seagrass species, changing species composition and shifts in tissue contents. Our study confirms that nutrient loads are more important than water nutrient concentrations. We identify seagrass system variables that are suitable indicators for sediment and nutrient loading, also in rapid survey scenarios with once-only measurements.
Show more [+] Less [-]Benthic foraminifera distribution in a tourist lagoon in Rio de Janeiro, Brazil: A response to anthropogenic impacts
2011
Vilela, Claudia Gutterres | Batista, Daniele Silva | Baptista Neto, José Antonio | Ghiselli, Renato Olindo, Jr
Rodrigo de Freitas Lagoon, located in the Rio de Janeiro City, receives several types of polluted discharges. The knowledge of the sediment microfauna correlated with heavy metal and organic matter concentrations could supply important data about the conditions of the lagoon. The benthic foraminiferal assemblage presented larger diversity and more abundant samples in the lagoon entrance than in the inner area. The Ammonia tepida – Elphidiumexcavatum foraminiferal assemblage is characterized by dwarf, corroded and weak organisms. Agglutinated species were found only near the entrance. Low abundance values and sterility of five samples in the inner area (north/northeast) can be caused by high levels of heavy metals and organic matter. A. tepida shows negative correlation with increasing heavy metals values. PAHs and coprostanol high indexes, and the absence or low presence of microfauna in samples around the lagoon margin confirm illegal flows from gas stations and domestic sewage.
Show more [+] Less [-]A simple osmium post-fixation paraffin-embedment technique to identify lipid accumulation in fish liver using medaka (Oryziaslatipes) eggs and eleutheroembryos as lipid rich models
2011
Mondon, J.A. | Howitt, J. | Tosiano, M. | Kwok, K.W.H. | Hinton, D.E.
Hepatic lipidosis is a non-specific biomarker of effect from pollution exposure in fish. Fatty liver is often misdiagnosed or overlooked in histological assessments due to the decreasing application of specific fat procedures and stains. For example, ethanol dehydration in standard paraffin processing removes lipids, leaving vacuoles of which the precise nature is unknown. Lipids can be identified using osmium post-fixation in semi-thin resin sections or transmission electron microscopy. However, both are expensive and technically demanding procedures, often not available for routine environmental risk assessment and monitoring programs. The current emphasis to reduce and refine animal toxicity testing, requires refinement of the suite of histopathological techniques currently available to maximize information gained from using fish for toxicity testing and as bio-indicators of environmental quality. This investigation has successfully modified an osmium post-fixation technique to conserve lipids in paraffin-embedded tissues using medaka (Oryzias latipes) eleutheroembryos and eggs (embryos) as lipid rich models.
Show more [+] Less [-]Accumulation of trace elements in harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada
2011
Agusa, Tetsuro | Nomura, Kumiko | Kunito, Takashi | Anan, Yasumi | Iwata, Hisato | Tanabe, Shinsuke
Nineteen trace elements were determined in liver, muscle, kidney, gonads, and hair of 18 harp seals (Phoca groenlandica) from Pangnirtung in the Baffin Island, Canada. Concentrations of V, Mn, Fe, Cu, Mo, Ag, and Hg in the liver, Co, Cd, and Tl in the kidney, and Ba and Pb in the hair were significantly higher than those in other tissues. Significant positive correlations between Hg concentrations in the hair, and liver, kidney and testis imply usefulness of the hair sample for non-destructive monitoring of Hg in the harp seals. It is suggested that whereas Hg preferentially accumulates in the liver, the accumulation in other tissues is induced at higher hepatic Hg levels. In contrast, Se may not be accumulated in other tissues compared with the liver even at higher hepatic Hg levels because of the presence of excess Se for Hg detoxification in other tissues.
Show more [+] Less [-]Anthropogenic organic contaminants in water, sediments and benthic organisms of the mangrove-fringed Segara Anakan Lagoon, Java, Indonesia
2011
Dsikowitzky, Larissa | Nordhaus, Inga | Jennerjahn, Tim C. | Khrycheva, Polina | Sivatharshan, Yoganathan | Yuwono, Edy | Schwarzbauer, Jan
Segara Anakan, a mangrove-fringed coastal lagoon in Indonesia, has a high diversity of macrobenthic invertebrates and is increasingly affected by human activities. We found >50 organic contaminants in water, sediment and macrobenthic invertebrates from the lagoon most of which were polycyclic aromatic compounds (PACs). Composition of PACs pointed to petrogenic contamination in the eastern lagoon. PACs mainly consisted of alkylated PAHs, which are more abundant in crude oil than parent PAHs. Highest total PAC concentration in sediment was above reported toxicity thresholds for aquatic invertebrates. Other identified compounds derived from municipal sewage and also included novel contaminants like triphenylphosphine oxide. Numbers of stored contaminants varied between species which is probably related to differences in microhabitat and feeding mode. Most contaminants were detected in Telescopium telescopium and Polymesoda erosa. Our findings suggest that more attention should be paid to the risk potential of alkylated PAHs, which has hardly been addressed previously.
Show more [+] Less [-]DDT in endangered Galapagos sea lions (Zalophus wollebaeki)
2011
Alava, Juan José | Ross, Peter S. | Ikonomou, Michael G. | Cruz, Marilyn | Jimenez-Uzcátegui, Gustavo | Dubetz, Cory | Salazar, Sandie | Costa, Daniel P. | Villegas-Amtmann, Stella | Howorth, Peter | Gobas, Frank A.P.C.
We characterize for the first time the presence of DDT and its metabolites in tropical Galapagos sea lions (Zalophus wolleabeki). ∑DDT concentrations in Galapagos sea lion pups sampled in 2005 and 2008 ranged from 16 to 3070μg/kg lipid. Concentrations of ∑DDT in pups in 2008 averaged 525μg/kg lipid and were 1.9 times higher than that (281μg/kg lipid) detected in pups in 2005. These concentrations are lower than those reported in many pinnipeds elsewhere, comparable to those in Hawaiian monk seals, and higher than those in southern elephant seals. The health risk characterization showed that 1% of the male pups exceeded the p,p′-DDE toxic effect concentration associated with anti-androgenic effects reported in rats. The findings provide preliminary guidance on the relationship between DDT use and ecological impacts, serving as a reference point against which possible future impact of tropical DDT use can be assessed.
Show more [+] Less [-]Organochlorine pesticides in sediments of Laizhou Bay and its adjacent rivers, North China
2011
Zhong, Guangcai | Tang, Jianhui | Zhao, Zhen | Pan, Xiaohui | Chen, Yingjun | Li, Jun | Zhang, Gan
Organochlorine pesticides (HCHs, DDTs and HCB) have been investigated in sediments of Laizhou Bay and its adjacent rivers. The average concentrations of HCHs, DDTs and HCBs are 0.09ng/gdw, 0.59 and 0.05 for marine sediments and 0.55, 8.6 and 1.1 for riverine sediments, respectively. Laizhou Bay is less contaminated by HCHs and DDTs in comparison with other coastal regions around the world, including the other two biggest bays in Bohai Sea. Fresh input of lindane and dicofol-type DDT were found in several riverine sites. Relatively strong TOC-dependence of HCB distribution in the entire studied area suggested no point source existed and/or water–sediment equilibrium achieved. No significant difference of α/γ-HCH ratios have been observed between marine and riverine sediments. However, o,p′-DDT/p,p′-DDT ratios varied largely between the two regions.
Show more [+] Less [-]Arsenic, cadmium, lead and mercury in canned sardines commercially available in eastern Kentucky, USA
2011
Shiber, John G.
Seventeen samples of canned sardines, originating from six countries and sold in eastern Kentucky, USA, were analyzed in composites of 3–4 fish each for total arsenic (As), cadmium (Cd) and lead (Pb) by graphite furnace atomic absorption spectrophotometry (AAS) and for mercury (Hg) by thermal decomposition amalgamation and AAS. Results in μg/g wet: As 0.49–1.87 (mean: 1.06), Cd<0.01–0.07 (0.03), Pb<0.06–0.27 (0.11), Hg ND <0.09. Values fall generally within readings reported by others, but no internationally agreed upon guidelines have yet been set for As or Cd in canned or fresh fish. The incidence of cancers and cardiovascular diseases associated with As ingestion is extraordinarily high here. With the role of food-borne As in human illness presently under scrutiny and its maximum allowable limits in fish being reviewed, more studies of this nature are recommended, especially considering the potential importance of small pelagic fishes as future seafood of choice.
Show more [+] Less [-]