Assessment of the toxicity of the herbicide 2,4-D (dichlorophenoxyacetic acid and dimethylamine salt) in zebrafish (Danio rerio) embryos: bioenergetic, behavioral and metabolomics analysis

• Grant number: 24/01989-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: June 01, 2024
• End date: December 31, 2024
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Lilian Cristina Pereira
• Grantee: Cristina Viriato de Freitas
• Supervisor: Chantal Lanctot
• Host Institution: Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Institution abroad: Griffith University, Australia
• Associated to the scholarship: 20/07363-5 - Multiparameters for integrated toxicity assessment of 2,4-D herbicide (dichlorophenoxyacetic acid and dimethylamine salt) in zebrafish (Danio rerio), BP.DR

Abstract

2,4-D is one of the most used herbicides in the world. It is used to control broadleaf weeds in various crops such as sugar cane, rice, soybeans, wheat and others. In Brazil, this is the second most used active ingredient across the country. This pesticide has already been classified as extremely toxic to humans and the salt forms of 2,4-D are slightly toxic to aquatic organisms. Despite that, low environmental concentrations can affect fish development and increase their susceptibility to environmental stressors. For this reason, the objective of this study is to evaluate the sublethal physiological effects of the herbicide on zebrafish (Danio rerio) embryos. Specifically, we will investigate the effects of the active ingredient 2,4-D (dichlorophenoxyacetic acid) and a commercial 2,4-D formula (DMA 806) on embryonic bioenergenic, neurotoxicity and metabolism. Embryos will be exposed to 0 (negative and solvent control), 0.1, 1, 10, 30 µM of each chemical. Changes in embryonic bioenergetic (mitochondrial oxygen consumption), motor behaviors, and untargeted metabolite disruption will be assessed using state-of-the-art technologies, including the XF96 Seahorse analyzer, DanioVision video-tracking software, andNuclear Magnetic Resonance (NMR) spectroscopy, respectively, available at Griffith University's Australian Rivers Institute (ARI) and Institute for Drug Discovery (GRIDD). This sort of sensitive and high-throughput technique is also being applied to a range of aquatic organisms in toxicology and ecotoxicology research to assess the physiological impacts of a range of contaminants, including pesticides. This method can be applied to monitor polluted regions of Brazil, where agriculture represents an important source of environmental contaminants.