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Effects of the pharmaceuticals gemfibrozil and diclofenac on the marine mussel (Mytilus spp.) and their comparison with standardized toxicity tests Texte intégral
2011
Schmidt, Wiebke | O’Rourke, Kathleen | Hernan, Robert | Quinn, Brian
Human pharmaceuticals, like the lipid lowering agent gemfibrozil and the non-steroidal anti-inflammatory drug diclofenac are causing environmental concern. In this study, the marine mussel (Mytilus spp.) was exposed by injection to environmentally relevant and elevated (1μg/L and 1000μg/L) concentrations of both compounds and biomarker expression was observed. Gemfibrozil exposure induced biomarkers of stress (glutathione S-transferase and metallothionein) at both concentrations 24h and 96h after exposure, respectively. Biomarkers of damage (lipid peroxidation (LPO) and DNA damage) were significantly affected, as well as the biomarker for reproduction, alkali-labile phosphate assay, indicating the potential oxidative stress and endocrine disrupting effect of gemfibrozil. Diclofenac significantly induced LPO after 96h indicating tissue damage. Additionally standard toxicity tests using the marine species Vibrio fischeri, Skeletonema costatum and Tisbe battagliai showed differences in sensitivity to both drugs in the mg/L range. Results indicate a suite of tests should be used to give accurate information for regulation.
Afficher plus [+] Moins [-]Quantity, distribution, and impacts of coastal driftwood triggered by a typhoon Texte intégral
2011
Doong, Dong-Jiing | Chuang, Hui-Chieh | Shieh, Chjeng-Lun | Hu, Jian-hwa
Typhoon Morakot pounded Taiwan in 2009 with record-breaking rainfall, washing an unprecedented amount of driftwood into the sea that was partially deposited at the coastal areas. According to the satellite imagery analysis, more than three million trees fell and were washed away to occupy 83.2% of the Taiwanese coastline, including 52 fishing harbors. The amount cleaned-up was only 1/7 of the total coastal driftwood. It was found that the amount of coastal driftwood is not only related to the amount of precipitation but is also related to the distance from the location of the landslide to the river mouth and to the landslide area. The amount of accumulated coastal driftwood demonstrated log-profile declines with increasing distance to the river mouth. Nearshore current and wave motion are the critical factors for driftwood deposition. Much of the driftwood washed into the sea harmed the tourism and fishing industries, endangered navigation and oceanic activities, and impacted the marine environment and ecosystem.
Afficher plus [+] Moins [-]Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers Texte intégral
2011
Praca, Emilie | Laran, Sophie | Lepoint, Gilles | Thomé, Jean-Pierre | Quetglas, Antoni | Belcari, Paola | Sartor, Paolo | Dhermain, Frank | Ody, Denis | Tapie, Nathalie | Budzinski, Hélène | Dāsa, Kr̥shṇā
Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers Texte intégral
2011
Praca, Emilie | Laran, Sophie | Lepoint, Gilles | Thomé, Jean-Pierre | Quetglas, Antoni | Belcari, Paola | Sartor, Paolo | Dhermain, Frank | Ody, Denis | Tapie, Nathalie | Budzinski, Hélène | Dāsa, Kr̥shṇā
Risso’s dolphins, pilot whales and sperm whales rarely strand in the northwestern Mediterranean. Thus, their feeding ecology, through the analysis of stomach contents, is poorly known. The aim of this study was to gain further insight into the segregation/superposition of the diet and habitat of Risso’s dolphins, pilot whales and sperm whales using chemical tracers, namely, stable isotopes (δ¹³C, δ¹⁵N) and organochlorines. Significantly different δ¹⁵N values were obtained in Risso’s dolphins (11.7±0.7‰), sperm whales (10.8±0.3‰) and pilot whales (9.8±0.3‰), revealing different trophic levels. These differences are presumably due to various proportions of Histioteuthidae cephalopods in each toothed whale’s diet. Similar δ¹³C contents between species indicated long-term habitat superposition or corroborated important seasonal migrations. Lower congener 180 concentrations (8.20 vs. 21.73μg.g⁻¹ lw) and higher tDDT/tPCB ratios (0.93 vs. 0.42) were observed in sperm whales compared with Risso’s dolphins and may indicate wider migrations for the former. Therefore, competition between these species seems to depend on different trophic levels and migration patterns.
Afficher plus [+] Moins [-]Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers Texte intégral
2011
Praca, Emilie | Laran, Sophie | Lepoint, Gilles | Thomé, Jean Pierre | Quetglas, Antoni | Belcari, Paola | Sartor, Paolo | Dhermain, Franck | Ody, Denis | Tapie, Nathalie | Budzinski, Hélène | Das, Krishna
Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers Texte intégral
2011
Praca, Emilie | Laran, Sophie | Lepoint, Gilles | Thomé, Jean-Pierre | Quetglas, Antoni | Belcari, Paola | Sartor, Paolo | Dhermain, Frank | Ody, Denis | Tapie, Nathalie | Budzinski, Hélène | Das, Krishna
Risso’s dolphins, pilot whales and sperm whales rarely strand in the northwestern Mediterranean. Thus, their feeding ecology, through the analysis of stomach contents, is poorly known. The aim of this study was to gain further insight into the segregation/superposition of the diet and habitat of Risso’s dolphins, pilot whales and sperm whales using chemical tracers, namely, stable isotopes (d13C, d15N) and orga- nochlorines. Significantly different d15N values were obtained in Risso’s dolphins (11.7 ± 0.7‰), sperm whales (10.8 ± 0.3‰) and pilot whales (9.8 ± 0.3‰), revealing different trophic levels. These differences are presumably due to various proportions of Histioteuthidae cephalopods in each toothed whale’s diet. Similar d13C contents between species indicated long-term habitat superposition or corroborated impor- tant seasonal migrations. Lower congener 180 concentrations (8.20 vs. 21.73 lg.g 1 lw) and higher tDDT/ tPCB ratios (0.93 vs. 0.42) were observed in sperm whales compared with Risso’s dolphins and may indi- cate wider migrations for the former. Therefore, competition between these species seems to depend on different trophic levels and migration patterns.
Afficher plus [+] Moins [-]Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers Texte intégral
2011
Praca, Emilie | Laran, Sophie | Lepoint, Gilles | Thomé, Jean-Pierre | Quetglas, Antoni | Belcari, Paola | Sartor, Paolo | Dhermain, Frank | Ody, Denis | Tapie, Nathalie | Budzinski, Hélène | Das, Krishna
peer reviewed | Risso’s dolphins, pilot whales and sperm whales rarely strand in the northwestern Mediterranean. Thus, their feeding ecology, through the analysis of stomach contents, is poorly known. The aim of this study was to gain further insight into the segregation/superposition of the diet and habitat of Risso’s dolphins, pilot whales and sperm whales using chemical tracers, namely, stable isotopes (d13C, d15N) and orga- nochlorines. Significantly different d15N values were obtained in Risso’s dolphins (11.7 ± 0.7‰), sperm whales (10.8 ± 0.3‰) and pilot whales (9.8 ± 0.3‰), revealing different trophic levels. These differences are presumably due to various proportions of Histioteuthidae cephalopods in each toothed whale’s diet. Similar d13C contents between species indicated long-term habitat superposition or corroborated impor- tant seasonal migrations. Lower congener 180 concentrations (8.20 vs. 21.73 lg.g1 lw) and higher tDDT/ tPCB ratios (0.93 vs. 0.42) were observed in sperm whales compared with Risso’s dolphins and may indi- cate wider migrations for the former. Therefore, competition between these species seems to depend on different trophic levels and migration patterns.
Afficher plus [+] Moins [-]Bioaccumulation of trace metals in the submarine hydrothermal vent crab Xenograpsus testudinatus off Kueishan Island, Taiwan Texte intégral
2011
Peng, Shao-Hung | Hung, Jia-Jang | Hwang, Jiang-Shiou
The concentrations of ten trace metals were determined in the gills, muscles, hepatopancreas, and exoskeleton tissues of Xenograpsus testudinatus that lives around shallow and acidic hydrothermal vents off Kueishan Island, northeastern Taiwan. The analytical results demonstrate that the metal concentrations vary significantly with the type of crab tissue. The concentrations of Al, Cd, Co, Cu, Fe, Ni, and Zn are highest in the gills, whereas the concentration of Mn is highest in the exoskeleton. Cr and Pb concentrations are similar across the different tissues. The enhanced accumulation of most metals in the gills suggests the metal accumulation via the respiration pathway rather than the uptake of food. The results also reveal that the distribution patterns of metals in tissues are similar in the hepatopancreas and muscles, but very different in both the gills and the exoskeleton, perhaps because of the different pathways of metal utilization in the different crab tissues.
Afficher plus [+] Moins [-]The extent and historical trend of metal pollution recorded in core sediments from the artificial Lake Shihwa, Korea Texte intégral
2011
Ra, Kongtae | Bang, Jae-Hyun | Lee, Jung-Moo | Kim, Kyung-Tae | Kim, Eun-Soo
The vertical distribution of trace metals in sediment cores was investigated to evaluate the extent and the historical record of metal pollution over 30years in the artificial Lake Shihwa in Korea. A marked increase of trace metals after 1980 was observed due to the operation of two large industrial complexes and dike construction for a reclamation project. There was a decreasing trend of metal concentrations with the distance from the pollution source. The enrichment factor and pollution load index of the metals indicated that the metal pollution was mainly derived from Cu, Zn and Cd loads due to anthropogenic activities. The concentrations of Cr, Ni, Cu, Zn, As and Pb in the upper part of all core sediments exceeded the ERL criteria of NOAA. Our results indicate that inadequate planning and management of industrialization and a large reclamation project accomplished by dike construction have continued to strongly accelerate metal pollution in Lake Shihwa.
Afficher plus [+] Moins [-]Method for generating parameterized ecotoxicity data of dispersed oil for use in environmental modelling Texte intégral
2011
Nordtug, Trond | Olsen, Anders Johny | Altin, Dag | Meier, Sonnich | Overrein, Ingrid | Hansen, Bjørn Henrik | Johansen, Øistein
The aim of the work was to establish methodology for realistic laboratory-based test exposures of organisms to oil dispersions, specifically designed to generate parameterized toxicity data. Such data are needed to improve the value of numerical models used to predict fate and effects of oil spills and different oil spill responses. A method for continuous and predictable in-line production of oil dispersions with defined size distribution of different oil qualities was successfully established. The system enables simultaneous comparison between the effects of different concentrations of dispersion and their corresponding equilibrium water soluble fractions. Thus, net effects of the oil droplet fraction may be estimated. The method provides data for comparing the toxicity of oil dispersions generated both mechanically and with the use of chemical dispersions, incorporating the toxicity of both dissolved oil and droplets of oil.
Afficher plus [+] Moins [-]Disruption of Sema3A expression causes abnormal neural projection in heavy oil exposed Japanese flounder larvae Texte intégral
2011
Kawaguchi, Masahumi | Song, Jun-Young | Irie, Kouta | Murakami, Yasunori | Nakayama, Kei | Kitamura, Shin-Ichi
It has been well known that oil spills cause serious problems in the aquatic organisms. In particular, some species of teleosts, which develop on the sea surface thought to be affected by heavy oil (HO). During the embryogenesis, the nervous system is constructed. Therefore, it is important to study the toxicological effects of HO on the developing neurons. We exposed HO to eggs of Japanese flounder (Paralichthys olivaceus) and investigated the neural disorder. In larvae exposed by HO at the concentration of 8.75mg/L, the facial and lateral line nerves partially entered into the incorrect region and the bundle was defasciculated. Furthermore, in the HO-exposed larvae, Sema3A, a kind of axon guidance molecule, was broadly expressed in second pharyngeal arch, a target region of facial nerve. Taken together, we suggested the possibility that the abnormal expression of Sema3A affected by HO exposure causes disruption of facial nerve scaffolding.
Afficher plus [+] Moins [-]Effects of polychlorinated biphenyls on liver function and sexual characteristics in Japanese medaka (Oryzias latipes) Texte intégral
2011
Nakayama, Kei | Sei, Naomi | Handoh, Itsuki C. | Shimasaki, Yohei | Honjo, Tsuneo | Ōshima, Yūji
The effects of polychlorinated biphenyls (PCBs) on liver function and their differences between sexes were analyzed in Japanese medaka (Oryzias latipes) exposed to PCB126 or Kanechlor-400 (KC-400) using microarray. PCB exposure induced vitellogenin 1 expression in female medaka while suppressing choriogenin genes, which suggests that the effects of PCBs on estrogen-responsive genes do not occur directly through an estrogen receptor-mediated pathway. Reduction of androgen receptor alpha expression was also observed, and the gene expression pattern in PCB-exposed males changed to become more similar to that of females. Furthermore, changes in glycolysis-related genes indicate that PCB exposure might enhance glucose production via gluconeogenesis in the liver of medaka. Taken together, our results suggest that PCBs disrupt the endocrine system, especially androgen function, and may have the potential to cause demasculinizing effects. Additionally, induction of gluconeogenesis might be a response to maintain glucose levels consumed as a result of PCB exposures.
Afficher plus [+] Moins [-]Response of meiofaunal community with special reference to nematodes upon deployment of artificial reefs and cessation of bottom trawling in subtropical waters, Hong Kong Texte intégral
2011
Liu, Xiao-Shou | Xu, Wen-Zhe | Cheung, S.G. | Shin, Paul K.S.
The response of meiofaunal communities, especially nematodes, upon the deployment of artificial reefs and cessation of bottom trawling at a designated Marine Protected Area (MPA) in Hong Kong was studied through comparison of meiofaunal samples collected inside and outside the MPA. Total organic carbon (TOC), total Kjeldahl nitrogen (TKN), total phosphorus (TP), water content and silt–clay fraction in sediments were also analyzed. The level of TOC and TKN, and total meiofaunal and nematode abundance were significantly lower inside than that outside the MPA. Multivariate analysis also indicated differences in community structure. Biological traits analysis revealed that the proportions of nematodes with a clavate tail shape, longer adult length, stout body shape and k-strategy life history were higher inside than that outside the MPA. Such changes in nematode community structure could be a result of the presence of the artificial reefs and closure of the MPA from bottom trawling.
Afficher plus [+] Moins [-]Eutrophication and hypoxia in four streams discharging in Guanabara Bay, RJ, Brazil, a case study Texte intégral
2011
Aguiar, Valquiria Maria de Carvalho | Neto, José Antônio Baptista | Rangel, Carlos Marclei
Four streams in the city of São Gonçalo, were sampled to evaluate their potential as sources of nutrients to Guanabara Bay aiming to contribute with the government program to decrease the levels of pollution in this area. Imbuaçu, Guaxindiba, Marimbondo and Brandoas streams were sampled in 2007, 2008 and 2009. The streams revealed to be hipereutrophic with severe limitation of primary production by nitrogen, as shown by the N/P molar ratio. Phosphate levels were abnormally high varying between 4.35 and 130.82μM, whereas nitrate and nitrite ranged from 0.06 to 54.05μM and from 0.28 to 19.23μM, respectively. The streams also presented severe hypoxia and anoxia, with oxygen values varying from non-detected to 3.72mll⁻¹. Heavy loads of particulate suspended material were recorded in the studied streams, ranging between 6.00 and 400.00mgl⁻¹. The streams were considered inexorable sources of nutrients, enhancing the severe eutrophication process in Guanabara Bay.
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