title: Use of Gammarus fossarum (Amphipoda) embryo for toxicity testing: A case study with cadmium.
abstract: The effects of environmental contaminants on arthropod embryo stages have been poorly investigated in ecotoxicology. Moreover, many of these tests used hatching success as the sole metric, although it is possible to detect many more subtle effects. After a detailed description of embryogenesis in Gammarus fossarum, the present study reports on the sublethal effects of cadmium (Cd) exposure during embryonic development in G. fossarum. Embryos were first directly exposed in multiwell plates throughout the entire embryonic cycle (23 d) to increasing Cd concentrations (0, 1.5, and 3.0 μg/L; 120 embryos/concentration). Then, to assess the representativeness of the gammarid embryo assay performed in multiwell plates, embryos were exposed to similar Cd concentrations through the maternal open brood pouch. Next, to pinpoint sensitive periods of development, embryos were directly exposed to 3.0 μg/L of Cd for shorter periods of time: during gastrulation, organogenesis, and hatching. After hatching, the following parameters were measured in the newborn individuals: 1) body mass; 2) activity of the enzyme phenoloxidase, a key enzyme of the arthropod immune system; and 3) locomotor activity. Phenoloxidase activity was strongly inhibited in newborn individuals of embryos exposed (either in multiwell plates or in the maternal brood pouch) to 3.0 μg/L Cd throughout embryonic development. Furthermore, strong detrimental locomotor effects were observed in newborn individuals of embryos directly exposed to 3.0 μg/L. Exposures for shorter periods of time were not sufficient to induce such effects; no sensitive period could be determined. By bringing new insights into a critical time window of exposure, the gammarid embryo assay could provide a novel and interesting addition to existing bioassays in gammarids. Environ Toxicol Chem 2017;36:2436-2443. © 2017 SETAC.
authors.affiliation: Freshwater Systems, Ecology, and Pollution Research Unit, National Research Institute of Science and Technology for the Environment and Agriculture (Irstea), Villeurbanne, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Arambourou
authors.affiliation: Freshwater Systems, Ecology, and Pollution Research Unit, National Research Institute of Science and Technology for the Environment and Agriculture (Irstea), Villeurbanne, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Decamps
authors.affiliation: Freshwater Systems, Ecology, and Pollution Research Unit, National Research Institute of Science and Technology for the Environment and Agriculture (Irstea), Villeurbanne, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Quéau
authors.affiliation: Freshwater Systems, Ecology, and Pollution Research Unit, National Research Institute of Science and Technology for the Environment and Agriculture (Irstea), Villeurbanne, France.
authors.forename: Aymeric
authors.initials: A
authors.lastname: Dabrin
authors.affiliation: Viewpoint Life Sciences, Lissieu, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Neuzeret
authors.affiliation: Freshwater Systems, Ecology, and Pollution Research Unit, National Research Institute of Science and Technology for the Environment and Agriculture (Irstea), Villeurbanne, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Chaumot
mesh_terms: D033304:Amphipoda / Q000187:drug effects* / Q000196:embryology; D000818:Animals; D019256:Cadmium Chloride / Q000633:toxicity*; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000502:physiology; D047108:Embryonic Development / Q000187:drug effects; D008124:Locomotion / Q000187:drug effects; D018675:Toxicity Tests / Q000379:methods; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D019256:Cadmium Chloride
keywords: Amphipod; Embryogenesis; Locomotor behavior; Phenoloxidase activity; Toxic exposure