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Lacaze E.,University of Lyon | Lacaze E.,IRSTEA | Devaux A.,University of Lyon | Mons R.,IRSTEA | And 4 more authors.
Environmental Pollution | Year: 2011

The aim of this study was to propose a tool for freshwater environmental genotoxicity assessment using Gammarus fossarum, a high ecologically relevant species. In a first part, gammarids were caged upstream and downstream wastewater treatment plant effluent output. The sensitivity of genotoxic responses of haemocytes, oocytes and spermatozoa was compared using the Comet assay. Spermatozoa appeared to be the most sensitive, suitable and relevant cell type for genotoxicity risk assessment. In a second part, a watershed-scale study was conducted over 2 years to evaluate the applicability of our caging procedure. The genotoxic impact of a contamination was followed, taking into account seasonal variability. DNA damage in spermatozoa exhibited low basal level and low variability in control upstream sites, providing a reliable discrimination of polluted sites. Finally, DNA damage in caged G. fossarum has been proved to be a sensitive and reproducible tool for freshwater genotoxicity assessment. © 2011 Elsevier Ltd. All rights reserved. Source


Geffard O.,IRSTEA | Xuereb B.,IRSTEA | Chaumot A.,IRSTEA | Geffard A.,Laboratoire dEco Toxicologie | And 6 more authors.
Environmental Toxicology and Chemistry | Year: 2010

Among freshwater invertebrates, Gammarus fossarum is an important test organism and is currently used in ecotoxicology for acute and chronic assays; nevertheless, reproductive toxicity test methods are not yet available for these species. In the present study, the reproductive cycle in Gammarus fossarum was characterized in order to propose a reproductive toxicity test encompassing molting, follicle growth, and embryonic development that will provide a better understanding of the mode of action of chemicals disrupting these hormone-regulated processes. A detailed description of the reproductive cycle in Gammarus fossarum was obtained. As in some amphipods, molt and reproductive cycles of G. fossarum females occur concurrently, lasting 30 d at 12°C. Each molt stage is characterized by a specific marsupial embryonic development stage and the size of developing follicles visible on the ovarian membrane. Based on these results, a 21-d reproductive toxicity test is proposed for this species. This new bioassay was applied to identify the specific impact of different stressors: cadmium, methomyl, nonylphenol, and a starvation diet. Good reproducibility was obtained for different endpoints under control conditions and throughout the experiments. Preliminary robust reference values or benchmarks were proposed for these endpoints. Cadmium was found to specially inhibit secondary vitellogenesis. Nonylphenol had a specific concentration-dependent effect on embryonic development, with an increase in the percent abnormality from a concentration of 0.05 μg/L. A restricted food diet led to a significant delay in the molt cycle, which in turn induced inhibition of secondary vitellogenesis. © 2010 SETAC. Source


Palais F.,Laboratoire dEco Toxicologie | Jubeaux G.,Laboratoire dEco Toxicologie | Dedourge-Geffard O.,Laboratoire dEco Toxicologie | Biagianti-Risbourg S.,Laboratoire dEco Toxicologie | Geffard A.,Laboratoire dEco Toxicologie
Molluscan Research | Year: 2010

Activity profiles of amylase and carboxymethylcellulase (CMCase) were investigated in the crystalline style (CS) and the digestive diverticulae (DD) of the freshwater mussel Dreissena polymorpha. In both digestive tissues, highest amylase activities were measured at pH 6.5-7.5 and 25-30°C while highest CMCase activities were measured at pH 5.0-6.0 and 50°C. Amylase and CMCase activities were greater in the CS than in the DD, whereas amylase was more active than CMCase in both tissues. Activity profiles of amylase and CMCase were similar from one tissue to the other, suggesting a probable identity between the CS and the DD carbohydrases pools. © 2010 Malacological Society of Australasia & Society for the Study of Molluscan Diversity. Source

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