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Occurrence and assessment of perfluoroalkyl acids (PFAAs) in commonly consumed seafood from the coastal area of Bangladesh
2017
Habibullah-Al-Mamun, Md. | Ahmed, Md. K. | Raknuzzaman, M. | Islam, Md. S. | Ali, M.F. | Tokumura, M. | Masunaga, S.
This study reports the first evidence of the occurrence of perfluoroalkyl acids (PFAAs) in commonly consumed seafood from the coastal area of Bangladesh. Fifteen target PFAAs in 48 seafood samples (5 finfish and 2 shellfish species) were measured by HPLC-MS/MS. The results were comparable with other studies worldwide, particularly from China, Spain, Sweden, and USA. The majority of monitored PFAAs did not show clear seasonal variation. However, seafood from the southeast area (Coxs Bazar and Chittagong) showed relatively higher levels of PFAAs. Moreover, the dietary exposure assessment revealed that the daily intakes of PFAAs via seafood consumption were far less than the health-based guidelines, indicating low health risk for the Bangladeshi coastal residents."
Mostrar más [+] Menos [-]Biomarker responses of Cu-induced toxicity in European seabass Dicentrarchus labrax: assessing oxidative stress and histopathological alterations
2017
Díaz de Alba, Margarita Isabel | Canalejo Raya, Antonio | Granado Castro, María Dolores | Oliva Ramírez, Milagrosa | El Mai, Bahija | Córdoba García, Francisco | Troyano Montoro, Miriam | Espada Bellido, Estrella | Torronteras Santiago, Rafael | Galindo Riaño, María Dolores | Química Analítica
A comprehensive approach to chemical accumulation and biological effects of short-term Cu exposure in juveniles of European seabass (Dicentrarchus labrax) has been achieved. Fish were exposed to 0.01–10 mg L− 1 nominal Cu concentrations for 24–96 h. Metal concentrations in water and gills, liver, muscle and brain tissues were studied along with oxidative stress biomarkers (superoxide dismutase, catalase, glutathione peroxidase, lipid peroxidation). Induction of oxidative damage was observed in all the organs with differential antioxidant responses; gills appearing as the most sensitive from low environmentally water Cu concentrations as 0.01 mg L− 1. Histopathological alterations were also observed in liver and gills, even without a significant Cu accumulation. The results show that the combination of oxidative stress parameters, particularly lipid peroxidation and glutathione peroxidase activities, and histopathological alterations provide a good model fish and reliable early biomarkers for monitoring Cu pollution in seawater and might call for the protection agencies to revise the Cu environmental standards.
Mostrar más [+] Menos [-]Citizen scientists reveal: marine litter pollutes Arctic beaches and affects wild life
2017
Bergmann, Melanie | Lutz, Birgit | Tekman, Mine Banu | Gutow, Lars
Recent data indicate accumulation areas of marine litter in Arctic waters and significant increases over time. Beaches on remote Arctic islands may be sinks for marine litter and reflect pollution levels of the surrounding waters particularly well. We provide the first quantitative data from surveys carried out by citizen scientists on six beaches of Svalbard. Litter quantities recorded by cruise tourists varied from 9-524 g m-2 and were similar to those from densely populated areas. Plastics accounted for >80% of the overall litter, most of which originated from fisheries. Photographs provided by citizens show deleterious effects of beach litter on Arctic wildlife, which is already under strong pressure from global climate change. Our study highlights the potential of citizen scientists to provide scientifically valuable data on the pollution of sensitive remote ecosystems. The results stress once more that current legislative frameworks are insufficient to tackle the pollution of Arctic ecosystems.
Mostrar más [+] Menos [-]The effects of oil spills on marine fish: Implications of spatial variation in natural mortality
2017
Langangen, Øystein | Olsen, Erik Joel Steinar | Stige, Leif Christian | Ohlberger, Jan Philipp | Yaragina, Natalia A. | Vikebø, Frode Bendiksen | Bogstad, Bjarte | Stenseth, Nils Christian | Hjermann, Dag Øystein
publishedVersion
Mostrar más [+] Menos [-]Linking pollutant exposure of humpback whales breeding in the Indian Ocean to their feeding habits and feeding areas off Antarctica
2017
Das, Krishna | Malarvannan, Govindan | Dirtu, Alin | Dulau, Violaine | Dumont, Magali | Lepoint, Gilles | Mongin, Philippe | Covaci, Adrian | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Humpback whales, Megaptera novaeangliae, breeding off la Reunion Island (Indian Ocean) undergo large-scale seasonal migrations between summer feeding grounds near Antarctica and their reproductive winter grounds in the Indian Ocean. The main scope of the current study was to investigate chemical exposure of humpback whales breeding in the Indian Ocean by providing the first published data on this breeding stock concerning persistent organic pollutants (POPs), namely polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), DDT and its metabolites (DDTs), chlordane compounds (CHLs), polybrominated diphenyl ethers (PBDEs), and methoxylated PBDEs (MeO-PBDEs). Analyses of stable isotopes δ13C and δ15N in skin resulted in further insight in their feeding ecology, which was in agreement with a diet focused mainly on low trophic level prey species, such as krill from Antarctica. POPs were measured in all humpback whales in the order of HCB > DDTs > CHLs > HCHs > PCBs > PBDEs > MeO-BDEs. HCB (median: 24 ng.g-1 lw) and DDTs (median: 7.7 ng.g-1 lw) were the predominant compounds in all whale biopsies. Among DDT compounds, p,p’-DDE was the major organohalogenated pollutant, reflecting its long-term accumulation in humpback whales. Significantly lower concentrations of HCB and DDTs were found in females than in males (p<0.001). Other compounds were similar between the two genders (p>0.05). Differences in the HCB and DDTs suggested gender-specific transfer of some compounds to the offspring. POP concentrations were lower than previously reported results for humpback whales sampled near the Antarctic Peninsula, suggesting potential influence of their nutritional status and may indicate different exposures of the whales according to their feeding zones. Further investigations are required to assess exposure of southern humpback whales throughout their feeding zones.
Mostrar más [+] Menos [-]Marine litter in the Nordic Seas: Distribution composition and abundance
2017
Buhl-Mortensen, Lene | Buhl-Mortensen, Pål
Litter has been found in all marine environments and is accumulating in seabirds and mammals in the Nordic Seas. These ecosystems are under pressure from climatic change and fisheries while the human population is small. The marine landscapes in the area range from shallow fishing banks to deep-sea canyons. We present density, distribution and composition of litter from the first large-scale mapping of sea bed litter in arctic and subarctic waters. Litter was registered from 1778 video transects, of which 27% contained litter. The background density of litter in the Barents Sea and Norwegian Sea is 202 and 279 items/km2 respectively, and highest densities were found close to coast and in canyons. Most of the litter originated from the fishing industry and plastic was the second most common litter. Background levels were comparable to European records and areas with most littering had higher densities than in Europe. | publishedVersion
Mostrar más [+] Menos [-]Oviposition deterrent activity of basil plants and their essentials oils against Tuta absoluta (Lepidoptera: Gelechiidae)
2017
Yarou, Boni Barthélémy | Bawin, Thomas | Boullis, Antoine | Heukin, Stéphanie | Lognay, Georges | Verheggen, François | Francis, Frédéric
peer reviewed | The leafminer Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) is one of the most important pests of tomato, reducing crop yields by up to 100% in greenhouses and fields, in several countries globally. Because synthetic insecticides lead to resistance and have adverse effects on natural enemies and the health of producers, alternative control methods are needed. In this study, we assessed the oviposition-deterring effect of basil plants, Ocimum gratissimum L. and O. basilicum L. (Lamiaceae), using dual-choice behavioural assays performed in flight tunnels. We found that both plants significantly reduced T. absoluta oviposition behaviour on a tomato plant located nearby. To evaluate the potential effect of basil volatile organic compounds, we formulated essential oils of both plant species in paraffin oil, and observed a similar oviposition-deterring effect. Gas chromatography analyses detected 18 constituents in these essential oils which the major constituents included thymol (33.3%), p-cymene (20.4%), γ-terpinene (16.9%), myrcene (3.9%) in O. gratissimum and estragol (73.8%), linalool (8.6%), β-elemene (2.9%) and E-β-ocimene (2.6%) in O. basilicum. Twenty and 33 compounds were identified of the volatiles collected on O. gratissimum and O. basilicum plants, respectively. The main components include the following: p-cymene (33.5%), γ-terpinene (23.6%), α-terpinene (7.2%), α-thujene (6.7%) and E-α-bergamotene (38.9%) in O. gratissimum, and methyl eugenol (26.1%), E-β-ocimene (17.7%), and linalool (9.4%) in O. basilicum. Four compounds (α-pinene, β-pinene, Myrcene, Limonene) were common in essential oils and plants. Our results suggest the valuable potential of basil and associated essential oils as a component of integrated management strategies against the tomato leafminer.
Mostrar más [+] Menos [-]The use of wide-band transmittance imaging to size and classify suspended particulate matter in seawater
2017
Davies, Emlyn John | Brandvik, Per Johan | Leirvik, Frode | Nepstad, Raymond
An in situ particle imaging system for measurement of high concentrations of suspended particles ranging from 30 μm to several mm in diameter, is presented. The system obtains quasi-silhouettes of particles suspended within an open-path sample volume of up to 5 cm in length. Benchmarking against spherical standards and the LISST-100 show good agreement, providing confidence in measurements from the system when extending beyond the size, concentration and particle classification capabilities of the LISST-100. Particle-specific transmittance is used to classify particle type, independent of size and shape. This is applied to mixtures of oil droplets, gas bubbles and oil-coated gas bubbles, to provide independent measures of oil and gas size distributions, concentrations, and oil-gas ratios during simulated subsea releases. The system is also applied to in situ measurements of high concentrations of large mineral flocs surrounding a submarine mine tailings placement within a Norwegian Fjord. | publishedVersion
Mostrar más [+] Menos [-]Habitat selection by marine larvae in changing chemical environments
2017
Lecchini, David | Dixson, Danielle L. | Lecellier, Gael | Roux, Natacha | Frederich, Bruno | Besson, Marc | Tanaka, Y. | Banaigs, Bernard | Nakamura, Yohei | AFFISH-RC - Applied and Fundamental FISH Research Center - ULiège
peer reviewed | The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.
Mostrar más [+] Menos [-]Ecological impacts of atmospheric pollution and interactions with climate change in terrestrial ecosystems of the Mediterranean Basin: Current research and future directions
2017
Ochoa Hueso, Raúl | Munzi, Silvana | Alonso, Rocío | Arróniz-Crespo, María | Avila, Anna | Bermejo, Victoria | Bobbink, Roland | Branquinho, Cristina | Concostrina-Zubiri, Laura | Cruz, Cristina | Cruz de Carvalho, Ricardo | De Marco, Alessandra | Teresa, Dias | Elustondo, David | Elvira, Susana | Estebanez, Belén | Fusaro, Lina | Gerosa, Giacomo | Izquieta-Rojano, Sheila | Lo Cascio, Mauro | Marzuoli, Riccardo | Matos, Paula | Mereu, Simone | Merino, José | Morillas, Lourdes | Nunes, Alice | Paoletti, Elena | Paoli, Luca | Pinho, Pedro | Rogers, Isabel | Santos, Arthur | Sicard, Pierre | Stevens, Carly | Theobald, Mark | Biología
Los ecosistemas de la cuenca mediterránea, su biodiversidad única y los servicios clave que brindan están actualmente en riesgo debido a la contaminación del aire y el cambio climático; sin embargo, solo un número limitado de estudios aislados y geográficamente restringidos han abordado este tema, a menudo con resultados contrastantes. Las particularidades de la contaminación del aire en esta región incluyen altos niveles de O3 debido a las altas temperaturas del aire y la radiación solar, la estabilidad de las masas de aire y el predominio de la deposición seca de nitrógeno sobre la húmeda. Además, los factores abióticos y bióticos únicos (por ejemplo, el clima, el tipo de vegetación, la relevancia de los aportes de polvo del Sahara) que modulan la respuesta de los ecosistemas mediterráneos en diversas escalas espaciotemporales hacen que sea difícil comprender y, por tanto, predecir, las consecuencias de las actividades humanas que causan la contaminación del aire. Contaminación en la Cuenca Mediterránea. Por lo tanto, existe una necesidad urgente de implementar plataformas experimentales y de investigación coordinadas junto con redes más amplias de monitoreo ambiental en la región. En particular, es crucial contar con una red sólida de monitoreo de deposiciones junto con estimaciones de modelos, que posiblemente incluyan un conjunto de biomonitores comunes (idealmente criptógamas, un componente importante de la vegetación mediterránea), para ayudar a perfeccionar los mapas de deposición de contaminantes. Además, se debe prestar mayor atención a las medidas de diversidad funcional en futuros estudios sobre la contaminación del aire y el cambio climático para establecer el vínculo necesario entre la biodiversidad y la provisión de servicios ecosistémicos en los ecosistemas mediterráneos. A través de un esfuerzo coordinado, la comunidad científica mediterránea puede llenar los vacíos mencionados anteriormente y alcanzar una mayor comprensión de los mecanismos subyacentes a los efectos combinados de la contaminación del aire y el cambio climático en la cuenca mediterránea.
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