Micro-and Nanoplastic-Induced Biochemical Toxicity: Emerging Mechanisms and Health Risks Across Biological Systems

Micro-and Nanoplastic-Induced Biochemical Toxicity: Emerging Mechanisms and Health Risks Across Biological Systems

Kibibi Muthoni L.

Faculty of Science and Technology Kampala International University Uganda

ABSTRACT

Micro- and nanoplastics (MNPs) – particles derived from the fragmentation of larger plastic debris or manufactured intentionally at microscopic scales – are now ubiquitous across terrestrial, freshwater, marine, and atmospheric environments. Their small size, high surface area, and capacity to carry additives and sorbed pollutants enable them to interact with biological systems in ways that larger plastic debris cannot. This review synthesizes current understanding of the biochemical mechanisms underlying MNP toxicity across biological kingdoms, emphasizing oxidative stress, membrane and protein interactions, immune activation and inflammation, genotoxicity, endocrine disruption, and microbiome perturbation. We discuss routes of exposure and internalization, particle physicochemistry that modulates bioactivity, cross-species comparability of effects (plants, invertebrates, vertebrates, and humans), and methodological challenges in detection and hazard assessment. Gaps are highlighted: standardization of particle characterization and dose metrics, elucidation of chronic low-dose effects and mixture interactions, and development of mechanistic biomarkers translatable between models and humans. The review concludes with priority research directions and implications for risk assessment and public health policy, arguing that addressing MNP toxicity requires coordinated advances in analytical methods, experimental design, and cross-disciplinary communication.

Keywords: Microplastics, Nanoplastics, Oxidative stress, Endocrine disruption, Microbiome

 

CITE AS: Kibibi Muthoni L. (2026). Micro-and Nanoplastic-Induced Biochemical Toxicity: Emerging Mechanisms and Health Risks Across Biological Systems. IDOSR JOURNAL OF BIOCHEMISTRY, BIOTECHNOLOGY AND ALLIED FIELDS 11(1):21-25.  https://doi.org/10.59298/IDOSR/JBBAF/2026/1022125