The nexuses of micro(nano)plastics at environmental interfaces: Challenges in wastewater treatment and sustainable water management
B.G. Fouda-Mbanga, Bothwell Nyoni, Jabulani I. Mnyango, Calvin Phiri, Shanganyane Percy Hlangothi, Aliemeke Miracle, Ayeni Boluwatife, Olushuyi Celestina, Sonia Nadege Kenfack Voukeng, Chimaine Feudjio Tsague, Linda D. Nyamen, Pennie P. Mokolokolo, Julia Puseletso Mofokeng, Prince Ngobeni
Abstract
Micro(nano)plastics (MNPs) have emerged as persistent and complex pollutants, particularly within aquatic systems, with reported concentrations ranging from 0.1 to 1000 particles/L in freshwater and up to 10,000 particles/m 3 in marine environments. Their small size, diverse sources, and high surface reactivity enable interactions with co-contaminants and facilitate long-range transport, posing significant ecological and human health risks. This review explores the critical nexuses of MNPs at environmental interfaces, emphasizing their occurrence in aquatic systems, removal in wastewater treatment plants (WWTPs), and implications for sustainable water management. Bibliometric analysis was used to elucidate research trends, hotspots, and knowledge gaps. The paper discusses MNP transport, persistence, and ecological impacts, as well as current monitoring and detection techniques, highlighting limitations in quantification at sizes below 1 µ m. Conventional WWTPs typically achieve 20–90 % removal of MPs, depending on treatment stages, while advanced approaches—including membrane filtration, adsorption using biochar, carbon nanotubes, and graphene, as well as photocatalytic and electrochemical methods—demonstrate enhanced efficiencies, often exceeding 95 % removal under lab conditions. Policy frameworks and regulatory responses are examined, emphasizing the need for harmonized international standards. Finally, key research needs are outlined, including the development of standardized analytical methods, life cycle assessments, and integrated treatment strategies. Overall, this work provides a multidisciplinary overview of MNP pollution, guiding future research, technological innovation, and policy toward safer and more sustainable water systems.