International Research Journal of Pure and Applied Chemistry

Pesticides usage in agricultural fields to control pests is extremely toxic to non-target organisms like fish and affects fish health through impairment of metabolism, sometimes leading to mortality. Present study was carried out to determine the level of organochlorine pesticides residue in, water, sediments and two species of fish in Lake Geriyo. Soxhlet extraction process was employed for fish and sediment extraction using a mixture of hexane and acetone while water sample was extracted using dichloromethane liquid- liquid extraction method. The extracts were cleaned-up and analyzed using a gas chromatograph mass spectrometer (GC-MS). Endrin, aldrin, dieldrin, endosulfan I, endosulfan II, alpha BHC heptachlor and DDT were detected in the study area. While chlordane, methoxychlor, other isomers of BHC, DDT and their degradation products were not detected in all the samples analyzed. Dieldrin had the highest value of 0.566 mg/Kg in catfish while the lowest dieldrin value of 0.001 mg/Kg was found in Tilapia. The findings provide evidence of pollution of some the organochlorine pesticides residue in Lake Geriyo, this shows that the lake is slightly contaminated with organochlorine pesticides. Hence serious need for continuous monitoring of these pesticide residues in water, sediments, fish and the environment is required to in order to prevent various environmental and public health hazards that may arise from these pollutants.