Histology Based Whole Effluent Chronic Toxicity Testing of noodles processing company waste, using the gills of Clarias gariepinus as a biomarker.

Industrial effluents discharged into aquatic environments pose significant ecological and biological threats, particularly to aquatic species like Clariasgariepinus. This study investigated the chronic toxicity of effluents from the noodles food industry on the gills of Clariasgariepinus. The following known aquatic contaminants from food industries were selected as the effluent target chemical (TC) of concern: cadmium (Cd), copper (Cu), chromium (Cr), lead (Pb), nickel (Ni) and polyaromatic hydrocarbons (PAH). Effluent samples were analyzed for TC constituents, and their effects on fish were assessed under varying concentrations (6.25%, 12.5%, 25%, 50%, and 100%). Results revealed that most effluent parameters, such as Cu, Cr, and Ni, were within regulatory limits, while Cd levels (0.037 mg/L) exceeded permissible thresholds, highlighting significant contamination concerns. Gills histopathological evaluation revealed notable alterations, including epithelial detachment, lamellar degeneration, hyperplasia, and necrotic lesions. The study emphasizes the necessity for improved wastewater treatment protocols and stringent environmental regulations to safeguard aquatic ecosystems from industrial pollution.