Polymer identity determines nanoplastic toxicity: A toxicokinetic-toxicodynamic analysis.

imbalance, and membrane damage. In contrast, PVC NPs produced the strongest perturbations and exhibited the highest TD damage accumulation rate, demonstrating that polymer chemistry rather than internal dose alone governs toxic potential. Notably, PS, despite being the dominant model plastic in NP toxicology, was the least potent in our assays, whereas globally prevalent polymers such as PVC showed substantially stronger TD effects. These findings highlight the need to broaden NP risk assessment beyond PS-centric approaches and establish a predictive, mechanism-based framework for evaluating polymer-specific NP toxicity in aquatic ecosystems.