Quinclorac (QCR) Herbicide Induces Hepatotoxicity, Cytotoxicity, and Oxidative Stress in Zebrafish Liver (ZF-L) Cells: An Evaluation of a Seized Formulation

The seizure of agrochemicals is a persistent issue in Brazil, mainly in states bordering other South American countries, which experience the highest levels of agrochemical confiscations. We evaluated biochemical parameters, including oxidative stress, hepatotoxicity, and cytotoxicity of the herbicide quinclorac (QCR) using a sample obtained from a seizure. The herbicide was characterized using Gas Chromatography-Mass Spectrometry and thermal analysis. Additionally, hemolytic activity, along with MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), neutral red (NR), and lactate dehydrogenase (LDH) assays in Zebrafish Liver (ZF-L) cells, were performed to assess QCR cytotoxicity. The results showed IC50 values of 19.83 µg/mL for erythrocytes and 1.78 µg/mL, 5.13 µg/mL, and 0.95 µg/mL for MTT, NR, and LDH assays, respectively. A median IC50 of 3.46 µg/mL was used for cholinesterase (COL) and aspartate aminotransferase (AST) dosages, as well as oxidative stress assays, which revealed an increase in reactive oxygen species (ROS) production, along with a decrease in total sulfhydryl (SH) content and the activities of superoxide dismutase (SOD) and catalase (CAT). Furthermore, QCR exposure resulted in elevated AST levels, indicative of liver damage, and a biphasic response in COL activity, with a significant reduction at higher concentrations. Our research indicates that QCR induces hepatotoxicity and cytotoxicity via oxidative stress in the ZF-L cell line under in vitro conditions.