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Chronic dietary exposure to pyrolytic and petrogenic mixtures of PAHs causes physiological disruption in zebrafish—part II: behavior 全文
2014
Vignet, Caroline | Le Menach, Karyn | Lyphout, Laura | Guionnet, Tiphaine | Frère, Laura | Leguay, Didier | Budzinski, Hélène | Cousin, Xavier | Bégout, Marie-Laure | Unité Biogéochimie et Ecotoxicologie (BE) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Ressources Halieutiques La Rochelle-L'Houmeau (LRHLR) ; Unité Halieutique Gascogne Sud (HGS) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Laboratoire de Physiologie et Génomique des Poissons (LPGP) ; Institut National de la Recherche Agronomique (INRA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes (Biosit : Biologie - Santé - Innovation Technologique) | ANR project ConPhyPoP (CES 09_002) and CPER A2E ; European Union and European Fund for Regional Development ; Région Poitou-Charentes ; Institut Français de Recherche pour l’Exploitation de la Mer ; LABEX COTE cluster of excellence “Continental to coastal ecosystems” | ANR-09-CESA-0002,CONPHYPOP,Contamination et physiologie des poissons aux polluants(2009) | ANR-10-IDEX-0003,IDEX BORDEAUX,Initiative d'excellence de l'Université de Bordeaux(2010)
International audience | In the last 10 years, behavior assessment has been developed as an indicator of neurotoxicity and an integrated indicator of physiological disruption. Polycyclic aromatic hydrocarbon (PAH) release into the environment has increased in recent decades resulting in high concentrations of these compounds in the sediment of contaminated areas. We evaluated the behavioral consequences of long-term chronic exposure to PAHs, by exposing zebrafish to diets spiked with three PAH fractions at environmentally relevant concentrations. Fish were exposed to these chemicals from their first meal (5 days postfertilization) until they became reproducing adults (at 6 months old). The fractions used were representative of PAHs of pyrolytic (PY) origin and of two oils differing in composition (a heavy fuel oil (HO) and a light crude oil (LO)). Several tests were carried out to evaluate circadian spontaneous swimming activity, responses to a challenge (photomotor response), exploratory tendencies, and anxiety levels. We found that dietary PAH exposure was associated with greater mobility, lower levels of exploratory activity, and higher levels of anxiety, particularly in fish exposed to the HO fraction and, to a lesser extent, the LO fraction. Finally, our results indicate that PAH mixtures of different compositions, representative of situations encountered in the wild, can induce behavioral disruptions resulting in poorer fish performance.
显示更多 [+] 显示较少 [-]A spatiotemporal model for predicting grain aphid population dynamics and optimizing insecticide sprays at the scale of continental France 全文
2014
Ciss, Mamadou | Parisey, Nicolas | Moreau, Fabrice | Dedryver, Charles-Antoine | Pierre, Jean-Sébastien | Institut de Génétique, Environnement et Protection des Plantes (IGEPP) ; Institut National de la Recherche Agronomique (INRA)-Université de Rennes (UR)-AGROCAMPUS OUEST | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) | ARVALIS - Institut du Végétal [Boigneville] ; ARVALIS - Institut du végétal [Paris] | Bourse CIFRE | INRA-Université Rennes I-Arvalis
International audience | We expose here a detailed spatially explicit model of aphid population dynamics at the scale of a whole country (Metropolitan France). It is based on convection-diffusionreaction equations, driven by abiotic and biotic factors. The target species is the grain aphid, Sitobion avenae F., considering both its winged and apterousmorphs. In this preliminary work, simulations for year 2004 (an outbreak case) produced realistic aphid densities, and showed that both spatial and temporal S. avenae population dynamics can be represented as an irregular wave of population peak densities from southwest to northeast of the country, driven by gradients or differences in temperature, wheat phenology, and wheat surfaces. This wave pattern fits well to our knowledge of S. avenae phenology. The effects of three insecticide spray regimes were simulated in five different sites and showed that insecticide sprays were ineffective in terms of yield increase after wheat flowering. After suitable validation, which will require some further years of observations, the model will be used to forecast aphid densities in real time at any date or growth stage of the crop anywhere in the country. It will be the backbone of a decision support system, forecasting yield losses at the level of a field. The model intends then to complete the punctual forecasting provided by older models by a comprehensive spatial view on a large area and leads to the diminution of insecticide sprayings in wheat crops.
显示更多 [+] 显示较少 [-]Developmental toxicity of PAH mixtures in fish early life stages. Part I: adverse effects in rainbow trout 全文
2014
Le Bihanic, Florane | Morin, Bénédicte | Cousin, Xavier | Le Menach, Karyn | Budzinski, Hélène | Cachot, Jérôme | Université Sciences et Technologies - Bordeaux 1 (UB) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Physiologie et Génomique des Poissons (LPGP) ; Institut National de la Recherche Agronomique (INRA)-Structure Fédérative de Recherche en Biologie et Santé de Rennes (Biosit : Biologie - Santé - Innovation Technologique) | Unité Biogéochimie et Ecotoxicologie (BE) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | ANR ConPhyPop (2009-002) ; CPER A2E ; European Regional Development Fund ; GDR EXECO ; Aquitaine Region ; Ministère de l'Enseignement Supérieur et de la Recherche
A new gravel-contact assay using rainbow trout, Oncorhynchus mykiss, embryos was developed to assess the toxicity of polycyclic aromatic hydrocarbons (PAHs) and other hydrophobic compounds. Environmentally realistic exposure conditions were mimicked with a direct exposure of eyed rainbow trout embryos incubated onto chemical-spiked gravels until hatching at 10 °C. Several endpoints were recorded including survival, hatching delay, hatching success, biometry, developmental abnormalities, and DNA damage (comet and micronucleus assays). This bioassay was firstly tested with two model PAHs, fluoranthene and benzo[a]pyrene. Then, the method was applied to compare the toxicity of three PAH complex mixtures characterized by different PAH compositions: a pyrolytic extract from a PAH-contaminated sediment (Seine estuary, France) and two petrogenic extracts from Arabian Light and Erika oils, at two environmental concentrations, 3 and 10 μg g−1 sum of PAHs. The degree and spectrum of toxicity were different according to the extract considered. Acute effects including embryo mortality and decreased hatching success were observed only for Erika oil extract. Arabian Light and pyrolytic extracts induced mainly sublethal effects including reduced larvae size and hemorrhages. Arabian Light and Erika extracts both induced repairable DNA damage as revealed by the comet assay versus the micronucleus assay. The concentration and proportion of methylphenanthrenes and methylanthracenes appeared to drive the toxicity of the three PAH fractions tested, featuring a toxic gradient as follows: pyrolytic < Arabian Light < Erika. The minimal concentration causing developmental defects was as low as 0.7 μg g−1 sum of PAHs, indicating the high sensitivity of the assay and validating its use for toxicity assessment of particle-bound pollutants.
显示更多 [+] 显示较少 [-]Pacific oyster (Crassostrea gigas) hemocyte are not affected by a mixture of pesticides in short-term in vitro assays 全文
2014
Moreau, Pierrick | Burgeot, Thierry | Renault, Tristan
Pesticides are frequently detected in estuaries among the pollutants found in estuarine and coastal areas and may have major ecological consequences. They could endanger organism growth, reproduction or survival. In the context of high mortality outbreaks affecting Pacific oysters, Crassostrea gigas, in France since 2008, it appears of importance to determine the putative effects of pesticides on oyster susceptibility to infectious agents. Massive mortality outbreaks reported in this species, mainly in spring and summer, may suggest an important role played by the seasonal use of pesticides and freshwater input in estuarine areas where oyster farms are frequently located. To understand the impact of some pesticides detected in French waters, their effects on Pacific oyster hemocytes were studied through short-term in vitro experiments. Bivalve immunity is mainly supported by hemocytes eliminating pathogens by phagocytosis and producing compounds including lysosomal enzymes and antimicrobial molecules. In this study, oyster hemocytes were incubated with a mixture of 14 pesticides and metaldehyde alone, a molecule used to eliminate land mollusks. Hemocyte parameters including dead/alive cells, nonspecific esterase activities, intracytoplasmic calcium, lysosome number and activity and phagocytosis were monitored by flow cytometry. No significant effect of pesticides tested at different concentrations was reported on oyster hemocytes maintained in vitro for short-term periods in the present study. It could be assumed that these oyster cells were resistant to pesticide exposure in tested conditions and developing in vivo assays appears as necessary to better understand the effects of polluants on immune system in mollucks.
显示更多 [+] 显示较少 [-]Chronic dietary exposure to pyrolytic and petrogenic mixtures of PAHs causes physiological disruption in zebrafish - part I: Survival and growth 全文
2014
Vignet, Caroline | Le Menach, Karyn | Mazurais, David | Lucas, Julie | Perrichon, Prescilla | Le Bihanic, Florane | Devier, Marie-hélène | Lyphout, Laura | Frere, Laura | Begout, Marie-laure | Zambonino Infante, Jose-luis | Budzinski, Helene | Cousin, Xavier
The release of polycyclic aromatic hydrocarbons (PAHs) into the environment has increased very substantially over the last decades leading to high concentrations in sediments of contaminated areas. To evaluate the consequences of long-term chronic exposure to PAHs, zebrafish were exposed, from their first meal at 5 days post fertilisation until they became reproducing adults, to diets spiked with three PAH fractions at three environmentally relevant concentrations with the medium concentration being in the range of 4.6–6.7 μg g−1 for total quantified PAHs including the 16 US-EPA indicator PAHs and alkylated derivatives. The fractions used were representative of PAHs of pyrolytic (PY) origin or of two different oils of differing compositions, a heavy fuel (HO) and a light crude oil (LO). Fish growth was inhibited by all PAH fractions and the effects were sex specific: as determined with 9-month-old adults, exposure to the highest PY inhibited growth of females; exposure to the highest HO and LO inhibited growth of males; also, the highest HO dramatically reduced survival. Morphological analysis indicated a disruption of jaw growth in larvae and malformations in adults. Intestinal and pancreatic enzyme activities were abnormal in 2-month-old exposed fish. These effects may contribute to poor growth. Finally, our results indicate that PAH mixtures of different compositions, representative of situations encountered in the wild, can promote lethal and sublethal effects which are likely to be detrimental for fish recruitment.
显示更多 [+] 显示较少 [-]Responses of the European flounder (Platichthys flesus) to a mixture of PAHs and PCBs in experimental conditions 全文
2014
Dupuy, Celie | Galland, Claire | Devaux, Alain | Bony, Sylvie | Loizeau, Veronique | Danion, Morgane | Pichereau, Vianney | Fournier, Michel | Laroche, Jean
A multibiomarker approach was developed to evaluate the juvenile European flounder responses to a complex mixture of 9 polycyclic aromatic hydrocarbons (PAHs) and 12 polychlorinated biphenyls (PCBs). Exposure was performed through contaminated food pellets displaying: (1) PAH and PCB levels similar to those detected in the heavily polluted Seine estuary, respectively in sediments and in flatfish and (2) ten times these concentrations. Several biomarkers of the immune system (e.g., lysozyme concentration and gene expression of complement component C3 and TNF-receptor), DNA damage (e.g., Comet assay), energetic metabolism (e.g., activity of cytochrome C oxidase), detoxification process (e.g., cytochrome P450 1A1 expression level: CYP1A1; betaine homocysteine methyl transferase expression level: BHMT) were investigated after 14 and 29 days of contamination, followed by a 14-days recovery period. After 29 days of contamination, the detoxification activity (CYP1A1 expression level) was positively correlated with DNA damages; the increase of the BHMT expression level could also be related to the detoxification process. Furthermore, after the recovery period, some biomarkers were still upregulated (i.e., CYP1A1 and BHMT expression levels). The immune system was significantly modulated by the chemical stress at the two concentration levels, and the lysozyme appeared to be the most sensitive marker of the mixture impact.
显示更多 [+] 显示较少 [-]Development of a reference artificial sediment for chemical testing adapted to the MELA sediment contact assay 全文
2014
Le Bihanic, Florane | Perrichon, Prescilla | Landi, Laure | Clerandeau, Christelle | Le Menach, Karyn | Budzinski, Helene | Cousin, Xavier | Cachot, Jerome
Most persistent organic pollutants, due to their hydrophobic properties, accumulate in aquatic sediments and represent a high risk for sediment quality. To assess the toxicity of hydrophobic pollutants, a novel approach was recently proposed as an alternative to replace, refine and reduce animal experimentation: the medaka embryo–larval sediment contact assay (MELAc). This assay is performed with Japanese medaka embryos incubated on a natural sediment spiked with the compound being tested. With the aim of improving this assay, our study developed a reference exposure protocol with an artificial sediment specifically designed to limit natural sediment composition uncertainties and preparation variability. The optimum composition of the new artificial sediment was tested using a model polycyclic aromatic hydrocarbon (PAH), fluoranthene. The sediment was then validated with two other model PAHs, benz[a]anthracene and benzo[a]pyrene. Various developmental end points were recorded, including survival, embryonic heartbeat, hatching delay, hatching success, larval biometry and abnormalities. The final artificial sediment composition was set at 2.5 % dry weight (dw) Sphagnum peat, 5 % dw kaolin clay and 92.5 % dw silica of 0.2- to 0.5-mm grain size. In contrast with natural sediments, the chemical components of this artificial matrix are fully defined and readily identifiable. It is totally safe for fish embryos and presents relatively high sorption capacities for hydrophobic compounds. Studies with other hydrophobic and metallic contaminants and mixtures should be performed to further validate this artificial sedimen
显示更多 [+] 显示较少 [-]Long-term disruption of growth, reproduction, and behavior after embryonic exposure of zebrafish to PAH-spiked sediment 全文
2014
Vignet, Caroline | Devier, Marie-hélène | Le Menach, Karyn | Lyphout, Laura | Potier, Jeremy | Cachot, Jerome | Budzinski, Helene | Begout, Marie-laure | Cousin, Xavier
A natural sediment spiked with three individual polycyclic aromatic hydrocarbons (PAHs; pyrene, phenanthrene and benzo[a]pyrene) was used to expose zebrafish embryos and larvae during 4 days. The total PAH concentration was 4.4 μg g−1 which is in the range found in sediment from contaminated areas. Quantification of metabolites in the larvae after exposure confirmed the actual contamination of the larvae and indicated an active metabolism especially for pyrene and benzo[a]pyrene. After a transfer in a clean medium, the larvae were reared to adulthood and evaluated for survival, growth, reproduction, and behavior. Measured endpoints revealed a late disruption of growth (appearing at 5 months) and a trend toward a lower reproductive ability. Adults of embryos exposed to sediment spiked with PAHs displayed lethargic and/or anxiety-like behaviors. This latter behavior was also identified in offspring at larval stage. All together, these effects could have detrimental consequences on fish performances and contribution to recruitment.
显示更多 [+] 显示较少 [-]Developmental toxicity of PAH mixtures in fish early life stages. Part I: adverse effects in rainbow trout 全文
2014
Le Bihanic, Florane | Morin, Benedicte | Cousin, Xavier | Le Menach, Karyn | Budzinski, Helene | Cachot, Jerome
A new gravel-contact assay using rainbow trout, Oncorhynchus mykiss, embryos was developed to assess the toxicity of polycyclic aromatic hydrocarbons (PAHs) and other hydrophobic compounds. Environmentally realistic exposure conditions were mimicked with a direct exposure of eyed rainbow trout embryos incubated onto chemical-spiked gravels until hatching at 10 °C. Several endpoints were recorded including survival, hatching delay, hatching success, biometry, developmental abnormalities, and DNA damage (comet and micronucleus assays). This bioassay was firstly tested with two model PAHs, fluoranthene and benzo[a]pyrene. Then, the method was applied to compare the toxicity of three PAH complex mixtures characterized by different PAH compositions: a pyrolytic extract from a PAH-contaminated sediment (Seine estuary, France) and two petrogenic extracts from Arabian Light and Erika oils, at two environmental concentrations, 3 and 10 μg g−1 sum of PAHs. The degree and spectrum of toxicity were different according to the extract considered. Acute effects including embryo mortality and decreased hatching success were observed only for Erika oil extract. Arabian Light and pyrolytic extracts induced mainly sublethal effects including reduced larvae size and hemorrhages. Arabian Light and Erika extracts both induced repairable DNA damage as revealed by the comet assay versus the micronucleus assay. The concentration and proportion of methylphenanthrenes and methylanthracenes appeared to drive the toxicity of the three PAH fractions tested, featuring a toxic gradient as follows: pyrolytic < Arabian Light < Erika. The minimal concentration causing developmental defects was as low as 0.7 μg g−1 sum of PAHs, indicating the high sensitivity of the assay and validating its use for toxicity assessment of particle-bound pollutants.
显示更多 [+] 显示较少 [-]The coming of age of Microbial Ecotoxicology: report on the first two meetings in France 全文
2014
Ghiglione, Jean-francois | Martin-laurent, Fabrice | Stachowski-haberkorn, Sabine | Pesce, Stéphane | Vuilleumier, Stephane
Context and objectives Microorganisms are ubiquitous in soil, air, and water ecosystems, where they are key players of ecosystem services. Microbial ecotoxicology is an emerging interdisciplinary area of research which aims at investigating the impact of human activities on the diversity, abundance, and activity of microorganisms. In return, the results of such investigations hold the promise to provide novel ways of assessing in a sensitive way the impacts of diverse environmental disturbances and subsequent ecosystem responses. Thus and although the term itself is yet rarely encountered in the scientific literature, microbial ecotoxicology already addresses an increasing political and societal demand. In the French scientific landscape, which often mimics the famous (but sometimes indigestible) “mille-feuilles” pastry, microbial ecotoxicologists are scattered across many different research centers belonging to different research organizations and universities. This research field has thus lacked any visibility and remained unorganized until now. Formal organization of scientific activities may be considered a typical “froggies” concern (or ailment). Nevertheless, it is rather surprising that scientific journals and significant international conferences specifically devoted to microbial ecotoxicology have been missing so far, especially considering the plethoric range of journals and congresses devoted to microbial ecology and ecotoxicology. With these considerations in mind, the idea of organizing the French research community of microbial ecologists around concepts of ecotoxicology made its way, with the aim of sharing the necessity to overcome artificial boundaries that prevent progress in this promising field.
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