Jump to main content
Jump to site search

Issue 10, 2016
Previous Article Next Article

Metabolization and degradation kinetics of the urban-use pesticide fipronil by white rot fungus Trametes versicolor

Author affiliations

Abstract

Fipronil is a recalcitrant phenylpyrazole-based pesticide used for flea/tick treatment and termite control that is distributed in urban aquatic environments via stormwater and contributes to stream toxicity. We discovered that fipronil is rapidly metabolized (t1/2 = 4.2 d) by the white rot fungus Trametes versicolor to fipronil sulfone and multiple previously unknown fipronil transformation products, lowering fipronil concentration by 96.5%. Using an LC-QTOF-MS untargeted metabolomics approach, we identified four novel fipronil fungal transformation products: hydroxylated fipronil sulfone, glycosylated fipronil sulfone, and two compounds with unresolved structures. These results are consistent with identified enzymatic detoxification pathways wherein conjugation with sugar moieties follows initial ring functionalization (hydroxylation). The proposed pathway is supported by kinetic evidence of transformation product formation. Fipronil loss by sorption, hydrolysis, and photolysis was negligible. When T. versicolor was exposed to the cytochrome P450 enzyme inhibitor 1-aminobenzotriazole, oxidation of fipronil and production of hydroxylated and glycosylated transformation products significantly decreased (p = 0.038, 0.0037, 0.0023, respectively), indicating that fipronil is metabolized intracellularly by cytochrome P450 enzymes. Elucidating fipronil transformation products is critical because pesticide target specificity can be lost via structural alteration, broadening classes of impacted organisms. Integration of fungi in engineered natural treatment systems could be a viable strategy for pesticide removal from stormwater runoff.

Graphical abstract: Metabolization and degradation kinetics of the urban-use pesticide fipronil by white rot fungus Trametes versicolor

Back to tab navigation

Supplementary files

Publication details

The article was received on 07 Jun 2016, accepted on 22 Aug 2016 and first published on 24 Aug 2016


Article type: Paper
DOI: 10.1039/C6EM00344C
Citation: Environ. Sci.: Processes Impacts, 2016,18, 1256-1265
  •   Request permissions

    Metabolization and degradation kinetics of the urban-use pesticide fipronil by white rot fungus Trametes versicolor

    J. M. Wolfand, G. H. LeFevre and R. G. Luthy, Environ. Sci.: Processes Impacts, 2016, 18, 1256
    DOI: 10.1039/C6EM00344C

Search articles by author

Spotlight

Advertisements