Characterization of Microplastics Residue in Water and Biota of Majidun Estuarines, Lagos Nigeria

Microplastic contamination is a critical environmental issue impacting aquatic ecosystems worldwide. Due to their environmental persistence, microplastics degrade water quality, threaten aquatic biota, and pose potential health risks to humans through water/seafood consumption. Despite the global significance of this problem, no documented studies have assessed microplastic pollution in the Majidun River, Ikorodu, Lagos State, Nigeria. This study investigated the occurrence of microplastics in surface water and commercially available aquatic species in Majidun River, Ikorodu, Lagos State, Nigeria. Water samples were collected using amber bottles and analyzed for microplastic occurrence using Fourier-transform infrared spectroscopy (FTIR), while fish, Kribia kribensis, Chrysichthyes filamentous, Galeoides decadactylus, Clarias lazera, Carranx hippos and Monodactylus sebae) and crustacean species (Callinectes pallidus), were dissected to extract and analyze gastro-intestinal contents for microplastic contamination. The results revealed significant microplastic contamination in both the water and biota (fish and crab). Neoprene and Ethylene Propylene were the only polymers detected in the surface water. In the biota, eight microplastic polymers were identified: Polyacrylamide, Polyaramid, Nylon, Polybutylene terephthalate, Polyvinyl alcohol, Ethylene propylene, Polyurethane, and Neoprene. Microplastic occurrence was highest in Monodactylus sebae (23%), followed by Galeoides decadactylus (19%), Clarias lazera (19%), and Carranx hippos (18%). The lowest occurrences were recorded in Kribia kribensis, Chrysichthyes filamentous, and Callinectes pallidus (7% each). This study provides the first evidence of significant microplastic contamination in the Majidun River, highlighting the need for policies to mitigate microplastic pollution and raise awareness of its impacts on water quality, aquatic life, and human health.