title: DNA damage in Gammarus fossarum sperm as a biomarker of genotoxic pressure: intrinsic variability and reference level.
abstract: In the perspective of a biomonitoring application for assessing genotoxicity of freshwater ecosystems, the Comet assay has recently been developed on spermatozoa in the amphipod Gammarus fossarum, in order to propose a sensitive and reliable genotoxicity biomarker in an ecologically relevant freshwater species. The appropriate use of a genotoxicity biomarker requires good knowledge of its basal level and its natural variability related to intrinsic biotic and environmental abiotic factors. We propose a procedure for which the lowest biomarker variability related to methodological and intrinsic biotic factors is obtained and a reference value of biomarker basal response taking into account its spatio-temporal changes has been defined. A strong impact of spermatogenesis status and exposure time on the response to genotoxicant pressure was observed. These reports led us to select a standard organism, i.e., the mature male gammarid in precopula. No effect of temperature and conductivity on baseline DNA damage was observed in the laboratory for the tested range (6-24 °C and 300/600 μS cm⁻¹). Similarly, no spatio-temporal change relative to season or the physico-chemical characteristics of the water was recorded during the field survey. On the basis of these results, a reference level with maximal threshold values has been proposed for the standard gammarid.
authors.affiliation: Université de Lyon, ENTPE-INRA, Laboratoire des Sciences de l'Environnement, rue Maurice Audin, Vaulx en Velin, F-69518, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Lacaze
authors.forename: Alain
authors.initials: A
authors.lastname: Devaux
authors.forename: Guillaume
authors.initials: G
authors.lastname: Jubeaux
authors.forename: Raphaël
authors.initials: R
authors.lastname: Mons
authors.forename: Maud
authors.initials: M
authors.lastname: Gardette
authors.forename: Sylvie
authors.initials: S
authors.lastname: Bony
authors.forename: Jeanne
authors.initials: J
authors.lastname: Garric
authors.forename: Olivier
authors.initials: O
authors.lastname: Geffard
mesh_terms: D033304:Amphipoda / Q000187:drug effects*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004249:DNA Damage; D004784:Environmental Monitoring / Q000379:methods*; D008297:Male; D009152:Mutagenicity Tests / Q000592:standards; D009153:Mutagens / Q000592:standards / Q000633:toxicity*; D013091:Spermatogenesis / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000592:standards / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D009153:Mutagens; D014874:Water Pollutants, Chemical