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First detection of pectenotoxin-2 in shellfish associated with an intense spring bloom of Dinophysis acuminata on the central Chilean coast Full text
2020
Díaz, Patricio A. | Álvarez, Gonzalo | Seguel, Miriam | Marín, Andrés | Krock, Bernd
Diarrhetic shellfish poisoning (DSP) toxins and pectenotoxins (PTX) produced by endemic species of the genus Dinophysis, mainly D. acuta and D. acuminata, pose a big threat to public health, artisanal fisheries and the aquaculture industry in Southern Chile. This work reports the first detection of lipophilic toxins, including pectenotoxin-2 (PTX-2) and gymnodimine-A (GYM-A), in hard razor clam (Tagelus dombeii) associated with an unprecedented spring bloom −38.4 × 103 cells L−1 in integrated hose sampler (0–10 m) – of Dinophysis acuminata in coastal waters of central Chile. The socio-economic challenges to small-scale fisheries are discussed. The study points to the pressing need for sound policies to face unexpected HAB event, probably due to biogeographical expansions, with a focus on fisheries management, participation of stakeholders, and development of adaptive capacities.
Show more [+] Less [-]Simulating particle organic matter dispersal beneath Atlantic salmon fish farms using different resuspension approaches Full text
2020
Carvajalino-Fernandez, Marcos Antonio | Sævik, Pål Næverlid | Johnsen, Ingrid Askeland | Albretsen, Jon | Keeley, Nigel B.
An accurate representation of the particle organic matter (POM) footprint is necessary in order to effectively predict impacts upon benthic communities and the risk of excessive organic enrichment beneath aquaculture sea-cages. Consequently, bottom-related processes such as particle resuspension must be adequately parametrized and evaluated in the available numerical models. We implemented two approaches to model POM resuspension in a Lagrangian particle tracking model and compared their influence on footprint extension and gradients of depositional flux against a no-resuspension scenario. We performed simulations in both exposed and protected aquaculture locations, and at different stages of the Atlantic Salmon (Salmo salar) production cycle in Norway. Our results indicate that the use of sediment-dependent thresholds for resuspension has the potential to regulate the high levels of erosion produced when selecting a low critical value in constant-threshold approaches, particularly in dynamic environments with mixed sediment types. | publishedVersion
Show more [+] Less [-]Habitat selection by marine larvae in changing chemical environments Full text
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.
Show more [+] Less [-]Oviposition deterrent activity of basil plants and their essentials oils against Tuta absoluta (Lepidoptera: Gelechiidae) Full text
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.
Show more [+] Less [-]Histopathological lesions and DNA adducts in the liver of European 1 flounder (Platichthysflesus) collected in the Seine estuary versus two reference estuarine systems on the FrenchAtlantic coast
2013
Cachot , Jérôme(auteur de correspondance) (Université de Bordeaux, Talence(France).) | Cherel , Yan (INRA , Nantes (France). UMR 0703 Physiopathologie animale et biothérapies du muscle et du système nerveux) | Larcher , Thibaut (INRA , Nantes (France). UMR 0703 Physiopathologie animale et biothérapies du muscle et du système nerveux) | Pfohl-Leszkowicz , Annie (Université de Toulouse CNRS, Castanet-Tolosan(France).) | Laroche , Jean (Université de BrestLaboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la Mer, BrestPlouzané(France). UMR 6539) | Quiniou , Louis (Université de BrestLaboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la Mer, BrestPlouzané(France). UMR 6539) | Morin , Jocelyne (Institut Français de Recherche pour l'Exploitation de la Mer, Port en bessin(France).) | Schmitz , Julien (Institut Français du Pétrole, Rueil-Malmaison(France).) | Burgeot , Thierry (Institut Français de Recherche pour l'Exploitation de la Mer, Nantes(France). Département Polluants chimiques) | Pottier , Didier (Université de Caen Basse Normandie, Caen(France). UR ABTE EA 4651)
Environmental harm assessment of a wastewater discharge from Hammerfest LNG: A study with biomarkers in mussels (Mytilus sp.) and Atlantic cod (Gadus morhua) Full text
2013
Beyer, Jonny | Aarab, Nadia | Tandberg, Anne Helene Solberg | Ingvarsdottir, Anna | Bamber, Shaw Duncan | Børseth, Jan Fredrik | Camus, Lionel | Velvin, Roger
Biologically treated wastewater (WW) from the Hammerfest LNG (liquefied natural gas) plant is discharged to the sea. A study using biomarkers in mussels and Atlantic cod was performed to examine whether this discharge meets a zero harmful emission requirement. Caging of mussels close to the outfall and exposure of mussels and fish to WW in the laboratory were conducted, and a suite of contaminant responsive markers was assessed in exposed animals. In mussels the markers included chemical contaminant levels, haemocyte lysosomal instability and nucleus integrity, cellular energy allocation, digestive gland and gonad histopathology and shell-opening behaviour. In fish, biliary PAH metabolites and gill histopathology biomarkers were measured. A consistent cause-effect relationship between WW treatments and markers measured in test animals was not found. The results therefore indicate that the WW emission is unlikely to represent a significant stress factor for the local marine environment under the conditions studied. | acceptedVersion
Show more [+] Less [-]Toothed whales in the northwestern Mediterranean: Insight into their feeding ecology using chemical tracers Full text
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.
Show more [+] Less [-]Groundwater quality assessment of one former industrial site in Belgium using a TRIAD-like approach. | Evaluation de la qualité des eaux souterraines d'une friche industrielle belge suivant la méthodologie TRIAD. Full text
2011
Crévecoeur, Sophie | Debacker, Virginie | Joaquim-Justo, Célia | Gobert, Sylvie | Scippo, Marie-Louise | Dejonghe, Winnie | Martin, Patrick | Thomé, Jean-Pierre
peer reviewed | Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study. The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices)integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment. | Science of Sustainable Development (FRAC-WECO project, 2007-2010).
Show more [+] Less [-]Blood dynamics of mercury and selenium in northern elephant seals during the lactation period Full text
2011
Habran, Sarah | Debier, Cathy | Crocker, Dan | Houser, Dorian | Das, Krishna
peer reviewed | The effects of reproduction and maternal investment (i.e., milk transfer) on trace element levels remain poorly understood in marine mammals. We examined the blood dynamics of mercury (Hg) and selenium (Se) during lactation in the northern elephant seal (Mirounga angustirostris), a top predator from the North Pacific Ocean. Total Hg and Se levels were measured in whole blood and milk of 10 mother-pup pairs on days 5 and 22 of lactation. Both Hg and Se were transferred to offspring through the milk. Results suggested that the maternal transfer of Se was prominent during lactation, whereas the Hg transfer was larger during gestation. The lactation period affected Hg and Se levels in the blood of elephant seal mothers and pups. Physiological processes and their relationship to body condition should be considered carefully when interpreting trace element levels in the framework of biomonitoring.
Show more [+] Less [-]Relationships between vitamin A and PCBs in grey seal mothers and pups during lactation Full text
2010
Vanden Berghe, Marie | Mat, Audrey | Arriola, Aline | Polain, Stéphanie | Stekke, Valérie | Thomé, Jean-Pierre | Gaspart, Frédéric | Pomeroy, Paddy P | Larondelle, Yvan | Debier, Cathy
peer reviewed | A previous study has shown a simultaneous increase of vitamin A and PCBs in grey seal (Halichoerus grypus) milk at late lactation (Debier et al., 2004). Here we sought to understand this unexpected relationship by comparing the dynamics of vitamin A and PCBs in the different tissue compartments of transfer. Lactating grey seals and their pups were sampled longitudinally in Scotland during the 2006 breeding season. As blubber reserves decreased, concentrations of vitamin A and PCBs increased during lactation in the inner layer of maternal blubber. A concomitant rise was observed in milk and consequently in the serum of suckling pups. The similar dynamics of vitamin A and PCBs in milk and inner blubber suggest a common mechanism of mobilisation from maternal body stores and transfer into the milk. A panel data analysis highlighted a negative impact of PCBs in milk and pup serum on vitamin A status in pup serum. © 2009 Elsevier Ltd. All rights reserved.
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