Commercial Glyphosate Formulations Exceed Active Ingredient Toxicity via Mitochondrial ROS and Transcriptomic Disruption

Glyphosate is among the most widely used pesticides globally. Emerging evidence suggests that glyphosate-based herbicides (GBHs) are more toxic than glyphosate alone. In this study, we used HepG2 cells expressing mitochondrial-targeted Hyper7 to monitor H₂O₂ production and performed RNA sequencing to compare transcriptomic responses to glyphosate and a commercial GBH formulation. GBH exposure significantly elevated mitochondrial H₂O₂ levels compared to control and glyphosate-treated cells. Transcriptomic analysis revealed upregulation of gene ontology (GO) terms associated with oxidative stress and response to hydrogen peroxide, alongside downregulation of antioxidant enzyme genes and reduced PRDX3 protein, indicating impaired redox homeostasis. GBH also induced ER stress, marked by increased expression of stress-related genes (Ern1, Ddit3) and enrichment of GO terms for the unfolded protein response. GBH treatment upregulated genes involved in autophagy and apoptosis (Sqstm1, Bbc3, Map1lc3b), suggesting progressive stress response. Additionally, metabolic pathways were altered, with higher expression of Atf3 and Ppargc1a, and enrichment of GO terms including response to glucose and lipid metabolism regulation. These results indicate that GBH triggers complex stress and metabolic changes distinct from glyphosate alone, highlighting the importance of assessing full formulations to better evaluate potential health risks.