Cross-Taxa Distinctions in Mechanisms of Developmental Effects for Aquatic Species Exposed to Trifluralin

作者：Jill A. Awkerman, Candice M. Lavelle, W. Matthew Henderson, Becky L. Hemmer, Crystal R. Lilavois, Peggy S. Harris, Nick Zielinski, Marilynn D. Hoglund, Donna A. Glinski, Denise K. MacMillan, Jermaine Ford, Roland F. Seim, Elizabeth Moso, Sandy Raimondo · 发表于：Environmental Toxicology and Chemistry · 年份：2020 · DOI：10.1002/etc.4758 · 被引用次数：7 · 研究领域：Pharmaceutical and Antibiotic Environmental Impacts、Environmental Toxicology and Ecotoxicology、Anesthesia and Neurotoxicity Research

Standard ecological risk assessment practices often rely on larval and juvenile fish toxicity data as representative of the amphibian aquatic phase. Empirical evidence suggests that endpoints measured in fish early life stage tests are often sufficient to protect larval amphibians. However, the process of amphibian metamorphosis relies on endocrine cues that affect development and morphological restructuring and are not represented by these test endpoints. The present study compares developmental endpoints for zebrafish (Danio rerio) and the African clawed frog (Xenopus laevis), 2 standard test species, exposed to the herbicide trifluralin throughout the larval period. Danio rerio were more sensitive and demonstrated a reduction in growth measurements with increasing trifluralin exposure. Size of X. laevis at metamorphosis was not correlated with exposure concentration; however, time to metamorphosis was delayed relative to trifluralin concentration. Gene expression patterns indicate discrepancies in response by D. rerio and X. laevis, and dose-dependent metabolic activity suggests that trifluralin exposure perturbed biological pathways differently within the 2 species. Although many metabolites were correlated with exposure concentration in D. rerio, nontargeted hepatic metabolomics identified a subset of metabolites that exhibited a nonmonotonic response to trifluralin exposure in X. laevis. Linking taxonomic distinctions in cellular-level response with ecologically relevan...