The Bioaccumulation of BTEX and PCBs in Gymnarchus niloticus at Epe Lagoon, Nigeria

Aquatic ecosystems have become dumping grounds for human waste products, posing risks to food safety and integrity. This study evaluates the bioaccumulation of polychlorinated biphenyls (PCBs) and BTEX compounds (benzene, toluene, ethylbenzene, and xylene) in the tissues of Gymnarchus niloticus at Epe Lagoon. It assesses the integrity of the water and soil sediments. The researchers collected Gymnarchus niloticus fish, water, and soil samples from the study site (Epe Lagoon) and analysed them using gas chromatography–mass spectrometry (GC–MS) in accordance with standard procedures. They also calculated the bioaccumulation factors (BAFs) to assess contaminant transfer from the aquatic environment into fish tissue. The study found that BTEX compounds were generally present at low concentrations across all matrices (Gymnarchus niloticus fish tissue, water, and soil samples). However, the BAF value for benzene (4.7) was considerably high. In contrast, some PCB congeners were detected at concentrations above the regulatory threshold in the water sample. The BAF value also ascertains the bioaccumulation of PCB‑70 (2,3′,4,5‑tetrachlorobiphenyl) in the tissue of Gymnarchus niloticus. These findings highlight the need for sustained environmental monitoring and effective pollution management strategies to protect aquatic ecosystems and public health in the Epe Lagoon system.