Analysis of microplastic contamination and associated human health risks in Clarias gariepinus and Oreochromis niloticus from Kubanni Reservoir, Zaria Nigeria

• Published in: Environmental pollution (1987) 2025-01, Vol.364 (Pt 1), p.125328, Article 125328
• Main Authors: Onaji, Maria Onma, Abolude, David S., Abdullahi, Shuaibu Akpai, Faria, Lucas Del Bianco, Chia, Mathias Ahii
• Format: Article
• Language: English
• Subjects: Animals; Catfishes; Cichlids - metabolism; Commercial fish; Environmental Monitoring; Health risk assessment; Humans; Microplastics; Nigeria; Oxidative Stress; Risk Assessment; total weekly consumption; Water Pollutants, Chemical - analysis
• ISSN: 0269-7491; 1873-6424; 1873-6424
• DOI: 10.1016/j.envpol.2024.125328

Environmental safety has become a major concern in recent years due to the global increase in microplastic pollution. These ubiquitous, tiny, and potentially toxic plastic particles enter aquatic environments through weathering of larger plastics and the release of microbeads. Although numerous studies have focused on microplastic pollution in developed regions, information from developing countries remains limited. This study assessed the presence of MPs and associated oxidative stress responses in two commercial fish species, Clarias gariepinus (Catfish) and Oreochromis niloticus (Nile Tilapia), from Kubanni reservoir, Zaria, Nigeria, over six months spanning both the dry and rainy seasons. Fibers were identified as the most abundant MP particles, followed by fragments, films, and beads, in the order of fibers > fragments > films > beads. The highest fiber concentrations were recorded in the gills, with Clarias garipinus showing 11.5 MP items/individual and Oreochromis niloticus showing 22.5 MP items/individual. Black microplastics were predominant, and the most common ingested MP ranged from 1.0 to 2.0 mm. The primary polymers identified were polypropylene and polyethylene terephthalate. Evidence of oxidative stress and cellular damage was observed in the gills, liver, and dorsal muscles of both fish species, which correlated with MPs ingestion. According to recommendations from the European Food Safety Authority regarding fish consumption by children and adults, individuals consuming Clarias gariepinus and Oreochromis niloticus from the Kubanni reservoir may be exposed to between 70 and 700 MP items/organ. The risk associated with consuming MPs found in fish gills and guts was notably higher, posing significant concerns for human health. This study provides insights into microplastic contamination in commercially important fish from the Kubanni Reservoir and highlights the environmental and public health risks associated with consuming contaminated fish from this ecosystem. [Display omitted] •We assessed MPs contamination in Clarias gariepinus and Oreochromis niloticus.•Fiber was the most predominant MP found in the investigated fish.•Both fish species suffered oxidative stress as a function of MPs content.•Total daily intake levels were lower than those reported in other regions.•CDF showed a slightly higher risk for MP consumption in O. niloticus.