title: Diastereomeric and enantiomeric selective accumulation of cypermethrin in the freshwater mussel Unio gibbus and its effects on biochemical parameters.
abstract: Synthetic pyrethroids are a family of chiral pesticides with a large number of stereoisomers. Cypermethrin (CYP) is used in a variety of agricultural crops, but also has public health and veterinary uses. In this work, the freshwater mussel (Unio gibbus) was chosen to evaluate the stereoselectivity of CYP through the use of gas chromatography with mass-spectrometry. The effects of CYP on mussels were examined by measuring neurotoxicity and oxidative stress biomarkers during its uptake. The investigation was performed under laboratory conditions using nominal CYP concentrations C1=100 μg/L and C2=150 μg/L over 96 h. Preferential bioaccumulation of cis-CYP isomers was observed. Furthermore, enantiomeric characterization revealed enantioselective accumulation, most probably related to mussel metabolism. Antioxidant enzyme activities (superoxide dismutase (SOD), and catalase (CAT)), and levels of reduced glutathione (GSH) and malondialdehyde (MDA) were determined in digestive gland after 4 days of exposure. CYP significantly inhibited acetylcholine esterase activity, by 51% and 57%, respectively, in mussels treated with 100 and 150 μg/L doses. The highest and lowest CYP concentrations elicited an increase of 67 and 63%, respectively, in SOD activity compared to the controls, while CAT activity was increased by 65 and 73%. A statistically significant decrease in GSH levels (40%) was observed only with the highest CYP concentration tested (150 μg/L). In addition, lipid peroxidation was significantly higher (67%) than in controls. These results provided information on CYP-enantioselective uptake and potential biomarkers that could be effectively applied for the biomonitoring of freshwater ecosystem.
authors.affiliation: Laboratoire de Biosurveillance de l'Environnement (LBE), Unité d'Ecotoxicologie et d'Ecologie Côtière (GREEC), Faculté des Sciences de Bizerte, 7021 Zarzouna-Bizerte, Tunisia.
authors.forename: Abdelhafidh
authors.initials: A
authors.lastname: Khazri
authors.affiliation: Institut National des Sciences et Technologies de la Mer, 28 rue de 2 mars 1934, 2025 Salammbô, Tunisia.
authors.forename: Badreddine
authors.initials: B
authors.lastname: Sellami
authors.affiliation: Laboratoire de Biosurveillance de l'Environnement (LBE), Unité d'Ecotoxicologie et d'Ecologie Côtière (GREEC), Faculté des Sciences de Bizerte, 7021 Zarzouna-Bizerte, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Dellali
authors.affiliation: Water and Soil Quality Research Group, Dep. of Environmental Chemistry, IDÆA-CSIC, Jordi Girona, 18, 08034 Barcelona, Spain.
authors.forename: Cayo
authors.initials: C
authors.lastname: Corcellas
authors.affiliation: Water and Soil Quality Research Group, Dep. of Environmental Chemistry, IDÆA-CSIC, Jordi Girona, 18, 08034 Barcelona, Spain. Electronic address: eeeqam@cid.csic.es.
authors.forename: Ethel
authors.initials: E
authors.lastname: Eljarrat
authors.affiliation: Water and Soil Quality Research Group, Dep. of Environmental Chemistry, IDÆA-CSIC, Jordi Girona, 18, 08034 Barcelona, Spain.
authors.forename: Damià
authors.initials: D
authors.lastname: Barceló
authors.affiliation: Laboratoire de Biosurveillance de l'Environnement (LBE), Unité d'Ecotoxicologie et d'Ecologie Côtière (GREEC), Faculté des Sciences de Bizerte, 7021 Zarzouna-Bizerte, Tunisia.
authors.forename: Hamouda
authors.initials: H
authors.lastname: Beyrem
authors.affiliation: Laboratoire de Biosurveillance de l'Environnement (LBE), Unité d'Ecotoxicologie et d'Ecologie Côtière (GREEC), Faculté des Sciences de Bizerte, 7021 Zarzouna-Bizerte, Tunisia.
authors.forename: Ezzeddine
authors.initials: E
authors.lastname: Mahmoudi
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005618:Fresh Water; D011722:Pyrethrins / Q000378:metabolism*; D013237:Stereoisomerism
chemical_list: D011722:Pyrethrins; C017160:cypermethrin; D003577:Cytochrome P-450 Enzyme System
keywords: Biomarkers; Cypermethrin; Enantiomers; GC–MS–MS; Unio gibbus