Microplastics Pollution in Nigerian Aquatic Ecosystems: Sources, Pathways, Impacts, and Mitigation Strategies. A Review

Microplastics, MPs (< 5mm) are ubiquitous plastic contaminants in freshwater and marine environments. MPs have been increasingly documented across Nigerian aquatic systems, including rivers, lagoons, estuaries, sediments, seafood, and drinking waters. They arise from multiple primary and secondary sources, undergo complex transport and transformation pathways, and affect organisms across trophic levels. Evidence indicates widespread contamination with fibers and fragments dominated by polyethylene, polypropylene, and polyester at urban drainage and estuarine sinks, and detectable particles in sachet/bottled water and commercially harvested fish. Reports showed that land-based inputs dominate marine microplastic loads, which are transported into subsurface and Polar Regions by currents with effects ranging from physiological stress in organisms to potential human exposure through seafood and drinking water. This review synthesizes recent findings on major sources and environmental pathways, ecological and human-health impacts, and mitigation strategies tailored to Nigeria’s socio-environmental context. The article recommended targeted source-reduction (including enforcement of single-use plastic restrictions and alternatives for sachet water), technological upgrades in wastewater and stormwater trash capture at drainage outfalls and treatment, coordinated upstream interventions (product design, waste management, extended producer responsibility), exposure and health risks studies for high-risks occupational and coastal communities, long-term toxicology for chronic low-dose exposures (including nanoplastics), and standardized national monitoring framework. These steps are urgent to protect aquatic ecosystem services and public health in Nigeria.