A Comprehensive Review on Microplastics Pollution in Nigerian Aquatic Environments

Microplastics (MPs), defined as plastic particles smaller than 5 mm, have become persistent contaminants in aquatic environments worldwide. In Nigeria, growing evidence shows that these particles are widespread in rivers, lagoons, estuaries, sediments, and in food and drinking-water products consumed by the population. Their presence results from a wide combination of primary and secondary sources, including the breakdown of poorly managed plastic waste, wastewater discharges, storm-water runoff, industrial activities, and fishing operations. Once released, MPs undergo complex transport and transformation processes, accumulating in surface waters, sediments, and biological organisms. MPs have been found in commercially important fish species, bottled and sachet water, table salt, and river water, raising concerns about ecological degradation and potential human exposure. Documented impacts include physiological stress, reduced feeding efficiency, digestive obstruction in aquatic organisms, and possible human-health risks resulting from chemical additives and sorbed pollutants. This review synthesizes updated knowledge on the sources, pathways, ecological effects, and human-health implications of MPs in Nigeria’s aquatic systems. The methodology integrated peer-reviewed scientific literature, credible grey literature, government and non-governmental policy documents, websites, international assessments, and reputable news sources published between 2014 and 2026. It highlights the need for targeted policy actions such as source reduction, strengthened waste management, wastewater filtration improvements, public education, and standardized national monitoring frameworks. These interventions are essential for safeguarding aquatic biodiversity, ecosystem services, and public health in Nigeria.