Toxicity of Microplastics and Nanoplastics in Aquatic Systems in Interaction with Biological – Chemical Contaminants: Advances in Remediations

Microplastics and nanoplastics (MPs/NPs) have recently been recognized as critical emerging pollutants with significant effects on aquatic ecosystems and human health. Their nanoscale to microscale dimensions, extensive surface area, and hydrophobic properties enable them to adsorb and concentrate various contaminants, including pathogenic microorganisms, heavy metals, antibiotics, and persistent organic pollutants. These contaminant–plastic interactions not only enhance the mobility and persistence of hazardous substances in aquatic environments but also intensify their ecological toxicity, facilitate bioaccumulation, and drive trophic transfer across food webs. Consequently, MPs/NPs act as both pollutants and pollutant carriers, amplifying ecological disturbances and public health risks. This chapter provides a comprehensive overview of the toxicological impacts of MPs/NPs, their environmental dynamics, and the mechanistic pathways governing their interactions with co-occurring contaminants. Special attention is given to their role as vectors of pollutants and their impacts on aquatic biota and human systems. Recent advancements in removal technologies, ranging from conventional physical treatments to novel membrane and electrochemical methods, are critically discussed. The chapter also highlights current knowledge gaps, limitations in scalability, and the need for harmonized regulations. Ultimately, it calls for integrated strategies combining innovative science, sustainable engineering, and international policy frameworks to mitigate the escalating microplastic crisis.