An Integrative Toxicological Assessment of the Herbicide Tebuthiuron: Elucidating Biochemical, Transcriptomic, and Behavioral Responses in Developing Zebrafish (Danio rerio)

• Grant number: 25/15628-2
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: December 01, 2025
• End date: February 28, 2026
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Diego Ferreira Gomes
• Grantee: Giovane Gomes Ferreira
• Supervisor: Christopher J Martyniuk
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: University of Florida, Gainesville (UF), United States
• Associated to the scholarship: 25/00115-0 - Ecotoxicological effects of the insecticide imidacloprid and the fungicide tebuconazole on the native species Allonais chelata (Oligochaeta) exposed in laboratory and mesocosms, BP.IC

Abstract

Pesticides represent a significant threat to aquatic ecosystems due to their persistence and widespread use in agricultural areas, altering environments and exerting adverse effects on non-target organisms. Ecotoxicological studies are frequently conducted to determine how pesticides, whether isolated or in mixtures, impact aquatic species. Thus, the main objective of this proposal is to conduct an integrative toxicological assessment of the herbicide tebuthiuron, investigating its effects on biochemical, transcriptomic, and behavioral responses in developing zebrafish (Danio rerio). Experiments will be conducted under laboratory conditions, focusing on the early stages of zebrafish (embryos and larvae). Developing fish will be subjected to different concentrations of tebuthiuron, and endpoints such as survival, hatch rate, morphological assessments, mitochondrial respiration measurement, reactive oxygen species (ROS), apoptosis assessment, and behavioral analyses (Visual Motor Response - VMR Test) will be conducted. To investigate the underlying molecular mechanisms and qPCR validation will be performed. This study has the potential to deepen the understanding of the ecotoxicological effects resulting from tebuthiuron exposure in vertebrate aquatic organisms, filling critical gaps in current knowledge and strengthening the use of behavioral and molecular parameters as early indicators of ecological disturbances.