Comparative Bioaccumulation of Polybrominated Diphenyl Ethers (Pbdes) in Synodontis clarias and Tilapia zilli in Lekki Lagoon, Lagos, Nigeria

Document Type : Original Article

Authors

1 Department of Zoology, faculty of life Sciences, University of Lagos, Nigeria.

2 Department of Biological Sciences, Covenant University, Ota, Ogun State, Nigeria.

Abstract

This study investigates the bioaccumulation of polybrominated diphenyl ethers (PBDEs), specifically PBDE-183 (2,2',3,4,4',5',6-Heptabromodiphenyl ether), in two fish species, Tilapia zilli (T. zilli) and Synodontis clarias (S. clarias), within the Lekki Lagoon, Lagos, Nigeria. The study aim to ascertain the effects and magnitude of PBDE bioaccumulation and assess the major effects associated with the consumption of these fishes.. Sampling was conducted in various locations within the lagoon, with specific attention to areas exhibiting different turbidity levels potentially influenced by anthropogenic activities. Tissue samples from the intestines of both fish species were collected and subjected to rigorous biochemical analyses to detect and quantify PBDE concentrations. Notably, T. zilli exhibited significantly higher levels of PBDE-183, measuring 0.02 mg/g, compared to S. clarias. This differential bioaccumulation suggests species-specific susceptibilities, likely influenced by physiological and metabolic differences. The study reveals that elevated turbidity levels, particularly in the habitat of T. zilli, can be attributed to localized anthropogenic disturbances rather than upstream water influx. These disturbances may include industrial effluents, urban runoff, and inadequate waste management practices. Such activities introduce PBDEs into the aquatic environment through various pathways, including direct discharge, stormwater drainage, and improper disposal of PBDE-containing materials. This study underscores the urgent need for improved industrial regulations, effective waste management practices, and public awareness to reduce PBDE contamination. Implementing these measures is crucial to preserve the ecological integrity of Lekki Lagoon and protect its aquatic life. Regular monitoring and further research are recommended to track contamination trends, assess the effectiveness of mitigation strategies, and understand the long-term health impacts on fish populations and human consumers. The findings of this study highlight the significance of species-specific studies in environmental toxicology, providing valuable insights into the differential bioaccumulation of contaminants and their ecological implications. By addressing the anthropogenic sources of PBDEs, we can mitigate their environmental and health impacts, ensuring the sustainability of vital aquatic ecosystems such as Lekki Lagoon.

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