A comparative zebrafish atlas of metallic toxicity identifies vanadium as a multi-target neurobehavioral toxicant and reveals effective chelation protection.

Environmental contamination by metallic elements represents an emerging threat to neurobehavioral health. Rather than evaluating individual metals independently, we established a standardized high-throughput behavioral phenomics platform in adult zebrafish that integrates 3D locomotion tracking with mirror-biting (aggression) and predator-avoidance (fear) assays under identical exposure conditions, enabling systematic behavioral toxicity profiling and direct cross-metal prioritization across 37 metallic elements. Multivariate behavioral fingerprinting showed that elements such as HMs induced more variable and severe phenotypes than REEs, identifying vanadium as the highest-priority candidate associated with severe neurobehavioral disruption, with concentration-dependent progression from anxiety-like behavior to locomotor suppression, behavioral disengagement, and mortality. Brain RNA-seq of vanadium-exposed fish revealed coordinated suppression of adaptive immune signaling alongside induction of sterol and carbohydrate metabolic reprogramming, indicating broad brain-associated molecular perturbation accompanying the observed behavioral disruption. To mitigate this toxicity, we evaluated four natural chelators (chitosan, citric acid, sodium alginate, tannic acid) co-incubated with vanadium in exposure water. Citric acid conferred the strongest behavioral and survival protection, and brain transcriptomic profiling indicated that co-incubation spared fish from the mitochondrial damage and apoptotic priming induced by vanadium alone. The protection was, however, exposure-phase selective: comparison with post-exposure transfer suggested that citric acid primarily protects during co-exposure rather than by effectively reversing established toxicity. Together, these findings establish a scalable behavioral toxicity screening platform and a comparative atlas of metallic elements, while demonstrating water-borne chelation as a promising preventive, but not therapeutic, strategy for mitigating vanadium toxicity in aquatic environments.