Health consequences of paraquat exposure, a review

Paraquat (PQ) is a widely used herbicide with high toxicity to humans and animals. Exposure to PQ occurs through inhalation, ingestion, or dermal contact and can result in severe systemic poisoning. This narrative review synthesizes experimental and clinical evidence from 165 studies identified through searches of Web of Science, PubMed, and Scopus covering publications from January 1989 through February 2026. The review examines PQ-induced toxicity across multiple organ systems, including the lungs, kidneys, liver, heart, nervous system, gastrointestinal tract, and reproductive and endocrine systems. PQ exposure is associated with oxidative stress, inflammation, mitochondrial dysfunction, immune dysregulation, and cellular death, contributing to diverse organ-specific injuries. Experimental studies have also investigated potential links between PQ exposure and neurodegenerative processes, including those relevant to Parkinson's disease; however, epidemiological evidence remains heterogeneous. Current treatment options for PQ poisoning remain limited, underscoring the importance of prevention and exposure reduction. The principal contribution of this review is an integrated mechanistic framework linking oxidative stress, mitochondrial dysfunction, inflammatory signaling, immune dysregulation, and apoptosis to multi-organ toxicity. This framework highlights shared biological pathways across organ systems while identifying important gaps in translating experimental findings into clinical practice. Further research should prioritize improved exposure assessment, validation of relevant biomarkers, and rigorous evaluation of protective strategies and therapeutic interventions.