Neurotoxicity and teratogenicity induced by carbendazim and ametryn in zebrafish: Implications for environmental and biological health

Abstract

Ametryn (AMT) and Carbendazim (CBZ) are pesticides widely used in agricultural crops to control pests and increase food production efficiency. Despite their toxicological risks and questionable effectiveness, the real impacts of exposure to these compounds and their residues in the environment are still difficult to determine, particularly when lethal, sublethal, biochemical, and behavioral endpoints are not evaluated within the same experimental framework. This study aimed to evaluate the effects of acute exposure to AMT and CBZ in non-target organisms, using zebrafish (Danio rerio) as a model. Zebrafish embryos were exposed from 3 to 120 h post-fertilization to different concentrations of the chemicals: 0.2, 1.0, 2.0, 20, and 40 mg/L of AMT, and 0.07, 0.15, 0.3, 0.5, and 1 µg/L of CBZ (n = 20/group). Mortality, teratogenicity, cardiotoxicity, and neurotoxicity were assessed. High mortality and malformation induction were observed for both pesticides, with estimated LC₅₀ values of 1.33 mg/L for AMT and 0.02 µg/L for CBZ. Both pesticides induced increased heart rate compared to the control group. Furthermore, the pesticides reduced avoidance behavior and elevated reactive oxygen species (ROS) and apoptotic cells at concentrations below LC₅₀, evidencing their neurotoxic effects. These findings highlight the importance of integrating sublethal and neurobehavioral endpoints into ecological risk assessment of pesticide exposure.