Nanomaterial toxicity: a comprehensive review of mechanisms and mitigation strategies

Nanomaterials possess unique physicochemical properties such as high surface area-to-volume ratios, tunable optical and electronic behaviour, and enhanced reactivity that promote their diverse applications in medicine, electronics, catalysis, energy, and environmental remediation. However, these same properties can elicit adverse biological and ecological effects, necessitating careful evaluation of nanomaterial toxicity. Toxicological mechanisms include interaction with biological systems, oxidative stress induction, inflammatory responses, and altered biodistribution, all influenced by size, shape, surface chemistry, charge, and stability. This work reviews the current understanding of nanotoxicity pathways, emphasizing the role of physicochemical parameters in determining hazard potential. It further examines mitigation strategies including safer-by-design approaches, surface modification, rigorous risk assessment, adaptive regulatory frameworks, and safe usage and disposal practices. While advances have improved nanomaterial safety profiles, critical research gaps remain, notably in understanding long-term transformations, chronic low-dose and mixture exposures, and protein corona dynamics. Future development should integrate predictive modeling, life-cycle assessment, and functional designs promoting controlled degradation into benign products. By combining scientific innovation with effective governance, workplace safety, and public awareness, nanomaterials can be sustainably integrated into society, preserving their technological value while safeguarding human health and the environment.