Safety Evaluation of Ripe Banana Peel (Musa acuminata) Waste as a Potential Aquaculture Feed Additive through Acute Toxicity and Histopathological Studies in Juvenile Clarias gariepinus

Abstract

The safe use of agricultural wastes in aquaculture feeds requires prior toxicological assessment. This study evaluated the acute toxicity and histopathological effects of an ethanolic extract of ripe banana peel (Musa acuminata) in juvenile African catfish (Clarias gariepinus). Fish were exposed for 96 h to 0, 20, 25, 30, or 35 mg/L of the extract in two experimental batches, with 10 juveniles per aquarium. Mortality, behavioural responses, water quality, and histological changes in the gills and liver were assessed. No mortality occurred in the control. In Batch A, no mortality occurred at 20 or 25 mg/L, whereas Batch B recorded 20% mortality at both concentrations. Mortality reached 50% at 30 mg/L and 60% at 35 mg/L in both batches, and the 96-h median lethal concentration was estimated at 30 mg/L. Behavioural abnormalities, including air gulping, erratic swimming, respiratory distress, and vertical erection, generally intensified with concentration and exposure duration. Significant differences were observed in dissolved oxygen, temperature, pH, and conductivity across treatments. Gill architecture remained largely preserved, although mild lamellar alteration occurred at 30 mg/L. Liver sections showed steatosis, hepatocellular vacuolation, peripheral nuclear displacement, and vascular congestion; however, severe necrosis and complete architectural disruption were not observed. The extract therefore produced measurable acute toxicity at higher concentrations and mild to moderate tissue alterations. Chronic feeding trials and additional biochemical and histopathological assessments are required before its use as an aquaculture feed additive.