Zebrafish as an Integrated Analytical Framework for Mechanistic and Predictive Toxicity Assessment of Emerging Nano-Contaminants.

The rapid advancement of nanotechnology has outpaced the development of adequate toxicity assessment methods, necessitating innovative analytical frameworks for evaluating emerging nano-contaminants. The zebrafish (Danio rerio) has emerged as a versatile vertebrate model that enables a comprehensive evaluation of molecular, physiological and developmental responses to nano-contaminant exposure. This minireview synthesises recent advances in zebrafish-based nanotoxicology, emphasising the integration of physicochemical characterisation with biological responses to improve predictive toxicity assessment. Current evidence identifies oxidative stress as one of the most extensively characterised molecular initiating events, activating interconnected pathways involving mitochondrial dysfunction, inflammation and apoptosis, ultimately driving organ-specific and developmental toxicities. Combining physicochemical characterisation with multi-omics approaches, high-throughput phenotypic analyses and computational modelling enables a quantitative linkage between nanoparticle properties and toxicological outcomes within systems-level and adverse outcome pathway (AOP)-oriented frameworks. Together, these complementary approaches strengthen predictive toxicology while improving the mechanistic understanding of nanoparticle-induced toxicity across diverse classes of emerging nano-contaminants. Despite these advances, important challenges remain, including the lack of standardised protocols for nanoparticle characterisation and exposure, uncertainty in selecting appropriate exposure metrics and environmentally relevant experimental models. Addressing these limitations is essential for improving reproducibility, prediction accuracy and translational relevance. Overall, zebrafish-based analytical toxicology provides a comprehensive framework for advancing predictive nanotoxicology thereby supporting safer-by-design nanomaterial development and evidence-based risk assessment of emerging nano-contaminants.