Open AccessEndogenous and exogenous biomarker analysis in terrestrial phase amphibians (Lithobates sphenocephala) following dermal exposure to pesticide mixtures
Author(s) -
Donna A. Glinski,
S. Thomas Purucker,
Robin J. Van Meter,
Marsha C. Black,
W. Matthew Henderson
Publication year - 2019
Publication title -
environmental chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.616
H-Index - 62
eISSN - 1449-8979
pISSN - 1448-2517
DOI - 10.1071/en18163
Subject(s) - pesticide , amphibian , biology , metabolomics , metabolome , bioaccumulation , environmental chemistry , ecotoxicology , xenobiotic , toxicology , ecology , chemistry , biochemistry , bioinformatics , enzyme
Pesticide mixtures are frequently co-applied throughout an agricultural growing season to maximize crop yield. Therefore, non-target ecological species (e.g., amphibians) may be exposed to several pesticides at any given time on these agricultural landscapes. The objectives of this study were to quantify body burdens in terrestrial phase amphibians and translate perturbed metabolites to their corresponding biochemical pathways affected by exposure to pesticides as both singlets and in combination. Southern leopard frogs ( Lithobates sphenocephala ) were exposed either at maximum or 1/10 th maximum application rate to single, double, or triple pesticide mixtures of bifenthrin (insecticide), metolachlor (herbicide), and triadimefon (fungicide). Tissue concentrations demonstrate both facilitated and competitive uptake of pesticides when in mixtures. Metabolomic profiling of amphibian livers identified metabolites of interest for both application rates, however; magnitude of changes varied for the two exposure rates. Exposure to lower concentrations demonstrated down regulation in amino acids, potentially due to their being utilized for glutathione metabolism and/or increased energy demands. Amphibians exposed to the maximum application rate resulted in up regulation of amino acids and other key metabolites likely due to depleted energy resources. Coupling endogenous and exogenous biomarkers of pesticide exposure can be utilized to form vital links in an ecological risk assessment by relating internal dose to pathophysiological outcomes in non-target species.