Cellular and Systemic Impacts of Microplastics and Nanoplastics

Abstract Plastics are synthetic polymers that have become an essential part of everyday life due to their low cost, durability, and flexibility. However, plastics in the environment break down into microplastics (MPs, <5 mm) and nanoplastics (NPs, <0.1 µm), and are potential threats to ecosystems and general health. Micro- and nanoplastics (MNPs) are ubiquitous in air, water, and soil and can be ingested through consumption or inhaled through respiration. Once inside, MNPs can then enter cells via various pathways, such as endocytosis and diffusion. The interactions of MNPs with the cells depend on their size, shape, and surface properties. MNPs can cause oxidative stress, inflammation, organelle damage, membrane disruption, and cell death. Studies indicate that MNP exposure can cause reproductive toxicity, metabolic dysfunction, cognitive decline, and increased risk of cancer and chronic diseases. Harmful plastic additives such as phthalates, BPA, and PBDEs, and adsorbed pollutants, such as heavy metals and PAHs, further amplify the toxic effects. The synergistic impact of MNPs with these substances aggravates cellular damage. Given the global rise in plastic production and persistence of MNPs in the environment, urgent action is needed to protect ecology and human health. This paper advocates stricter regulations on plastic waste management, health-focused research, the development of bioremediation technologies, and the broader adoption of sustainable waste management practices. Understanding the pathways, toxicity, and long-term impacts of MNPs is necessary for developing effective public health policies and reducing future risks. Keywords: Microplastics, nanoplastics, cellular and systemic effects, environmental pollution