Toxicocinétique de la chlordécone chez la brebis

Abstract : In the French West Indies (FWI), farming animals can be exposed to CLD, a persistent organic pollutant (POP) bound to soil in contaminated areas. In order to produce safe animal products, this thesis was focused on the CLD’s fate in ewes. The aims were to determine by which way(s), in which form(s), in how much time, in which quantities and by which mechanisms, CLD would be eliminated from the animal body. In this thesis, two complementary approaches were followed. First it was necessary to improve the analytical methods especially for the metabolites in order to obtain more sensitive and reliable methods than the actual ones. In the analytical approach, methods for CLD and its metabolites were developed in various animal matrices suitable for the toxicokinetic studies. The extraction method was based on the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology and the analysis was performed with a liquid chromatography with tandem mass spectrometry (LC-MS/MS). Isotopic Standards were also used. Thanks to this work, sensitive, quick and reliable methods were obtained in animal matrices. The set-up methods in liver, feces and urine were validated with accuracy profiles according to the French Standard NF V03-110 and European Union guidelines. Limits of quantifications of 1.36 μg kg−1 and 2.50 μg kg−1 of fresh liver were respectively found for chlordecone and chlordecol (the CLD’s metabolite). Secondly, and thanks to the analytical development, in vivo toxicokinetic studies were performed to determine the fate of CLD in ewes. The second approach of this thesis was based on two toxicokinetic protocols realized in ewes. The results revealed that CLD is partially metabolized in chlordecol (CLDOH) by the chlordecone reductase in ewe’s liver. Then, CLD and CLDOH can be conjugated by UDP-glucuronosyl-transferases and sulfo-transferases in conjugated metabolites (CLD-C and CLDOH-C). It appeared that CLDOH is only an intermediate metabolite which is almost never quantified in the organism except in fat tissue. The major route of CLD elimination is in feces: 1/3 of the molecule is eliminated in its CLD’s form and 1/6 in its CLDOH’s form. The urinary way of CLD elimination is minor. Based on the obtained results, a compartmental model was proposed. It will allow to propose and to establish ovine decontamination strategies in the FWI.
Document type :
Theses
File URL :
http://docnum.univ-lorraine.fr/ulprive/DDOC_T_2018_0256_SAINT_HILAIRE.pdf
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-02127468
Contributor : Thèses Ul <>
Submitted on : Monday, May 13, 2019 - 2:46:03 PM
Last modification on : Friday, May 17, 2019 - 9:10:40 AM

Identifiers

  • HAL Id : tel-02127468, version 1

Citation

Maïlie Saint-Hilaire. Toxicocinétique de la chlordécone chez la brebis. Agronomie. Université de Lorraine, 2018. Français. ⟨NNT : 2018LORR0256⟩. ⟨tel-02127468⟩

Share

Metrics

Record views

8