Species differences of bioaccumulation, biotransformation and synergistic effects of two fungicides in two aquatic invertebrates - Archive ouverte HAL Accéder directement au contenu
Poster De Conférence Année : 2018

Species differences of bioaccumulation, biotransformation and synergistic effects of two fungicides in two aquatic invertebrates

Résumé

Numerous micropollutants have been detected concurrently in aquatic systems, but little is known about the mixture effects of micropollutants in aquatic organisms and the underlying mechanisms. Azole fungicides are known to act synergistically with other chemicals by inhibiting cytochrome P450 (CYP) catalyzed detoxification and thereby enhance the effect of already toxic substances in different organisms. Two widely used fungicide classes co-occur in surface water are strobilurin and azole fungicides. This study aimed to investigate the species’ sensitivity to both fungicide classes and to gain mechanistic insights on potential synergistic effects of azoles on strobilurin fungicides in non-target organisms. Therefore, we determined the toxicokinetics of a strobilurin fungicide azoxystrobin and an azole fungicide prochloraz in two aquatic invertebrate species Gammarus pulex and Hyalella azteca. Furthermore, we explored median lethal concentrations (LC50s) of azoxystrobin in the presence and absence of prochloraz, the inhibition strength (IC50s) of prochloraz, and its effect on the locomotory behavior of the two species. Bioaccumulation of azoxystrobin weresimilar in both species with bioaccumulation factors (BAFs) approximately 5 L kgww-1, while bioaccumulation of prochloraz was different in two species, with BAFs 57 and 110 L kgww-1in G. pulex and H. azteca, respectively.Many biotransformation products were found for both fungicides in both species, of which taurine and malonyl conjugates were only identified in H.azteca. Most BTPs result from oxidation and conjugation reactions, which occurred at the (E)-methyl β-methoxyacrylate group of azoxystrobin and imidazole ring of prochloraz. Prochloraz inhibited the CYP-catalyzed biotransformation of azoxystrobin in both species, leading to higher internal azoxystrobin concentrations and suggesting synergistic effects. The half maximal inhibition concentration of prochloraz IC50, PRZ, AZwas 0.1 and 0.02 μM in G. pulex and H. azteca, respectively. The LC50sof azoxystrobin alone were 157 and 200 μg L-1in G. pulexand H. Azteca, respectively. Prochloraz significantly decreased the LC50s of azoxystrobin in both species. Video-tracking of the locomotory behavior suggested that prochloraz induced hyperactivity inG. pulex, but not in H. azteca. Overall, results suggests H. aztecacomprise more diverse biotransformation reactions and G. pulextended to be more sensitive than H. aztecatoward prochloraz effects.

Domaines

Ecotoxicologie
Fichier non déposé

Dates et versions

hal-02898343 , version 1 (13-07-2020)

Identifiants

  • HAL Id : hal-02898343 , version 1

Citer

Qinjun Fu, A. Rösch, Caroline Vignet, D. Fedrizzi, Nina Cedergreen, et al.. Species differences of bioaccumulation, biotransformation and synergistic effects of two fungicides in two aquatic invertebrates. SETAC Europe 28th Annual Meeting, May 2018, Rome, Italy. . ⟨hal-02898343⟩
47 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More