title: Evaluation of epoxiconazole bioavailability in soil to the earthworm Aporrectodea icterica.
abstract: In soil, the determination of total concentration using an exhaustive extraction method has little relevance to evaluate the exposure of an organism to a chemical, because of sorption processes. This study aims to propose a mild extraction method to evaluate the bioavailability of the fungicide epoxiconazole to the earthworm Aporrectodea icterica. Experiments were conducted in soils presenting various textures and organic carbon contents, spiked with formulated epoxiconazole 7 to 56 days prior to their extraction. In parallel, the epoxiconazole concentration was determined in exposed earthworms and the fungicide's effects were evaluated by measuring weight gain, enzymatic activities and total protein contents. Among the various mild chemical solvents tested to evaluate the environmental availability of the fungicide, the 50 mM hydroxypropyl-β-cyclodextrin solution allowed to extract around 30% of epoxiconazole. This percentage corresponded to the ratio determined in exposed A. icterica under similar soil conditions. Furthermore, this mild method was demonstrated to be sensitive to soil sorption capacities and to ageing. The mild extraction method was then applied to explore the relationship between total and (bio)available concentrations in soil and in A. icterica, over 7- or 28-day exposure time. This demonstrated the proportionality between epoxiconazole concentration in earthworm and available in soil (up to 96%, with regression coefficient R(2) = 0.98). Sublethal effects on earthworm remained not significant.
authors: INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France. nelieu@versailles.inra.fr.|AgroParisTech, UMR 1402 ECOSYS, 78850, Thiverval-Grignon, France. nelieu@versailles.inra.fr.
authors: S
authors: S
authors: Nélieu
authors: INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France.|AgroParisTech, UMR 1402 ECOSYS, 78850, Thiverval-Grignon, France.
authors: G
authors: G
authors: Delarue
authors: INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France.|AgroParisTech, UMR 1402 ECOSYS, 78850, Thiverval-Grignon, France.|Plateforme Biochem-Env, INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France.
authors: E
authors: E
authors: Ollivier
authors: INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France.|INRA, UMR 1145 GENIAL, 91744, Massy, France.
authors: P
authors: P
authors: Awad
authors: INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France.
authors: F
authors: F
authors: Fraillon
authors: INRA, UMR 1402 ECOSYS, 78026, Versailles cedex, France.|AgroParisTech, UMR 1402 ECOSYS, 78850, Thiverval-Grignon, France.
authors: C
authors: C
authors: Pelosi
mesh_terms: D000818:Animals; D001682:Biological Availability; D004784:Environmental Monitoring / Q000379:methods*; D004852:Epoxy Compounds / Q000032:analysis* / Q000378:metabolism / Q000633:toxicity; D005659:Fungicides, Industrial / Q000032:analysis* / Q000378:metabolism / Q000633:toxicity; D009835:Oligochaeta / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism / Q000633:toxicity; D014230:Triazoles / Q000032:analysis* / Q000378:metabolism / Q000633:toxicity; D015430:Weight Gain / Q000187:drug effects
chemical_list: D004852:Epoxy Compounds; D005659:Fungicides, Industrial; D012987:Soil; D012989:Soil Pollutants; D014230:Triazoles; C109476:epoxiconazole
keywords: Ageing; Ecotoxicology; Enzymatic activities; Organic matter; Pesticide; Soil texture; Triazole; Weight gain