Levels of Organochlorine Pesticide Residues in Tissues of Fish Samples from River Benue, Vinikilang, Adamawa State, Nigeria

Abstract

This study aimed to determine organochlorine pesticide residues which include dichlorodiphenyldichloroethylene (o,p-DDE), 4,4’-  dichlorodiphenyldichloroethan (p,p’-DDD), 2,4’dichlorodiphenyldichloroethan (o,p’-DDD), 2,4’-dichlorodiphenyltrichloroethane (o,p’-DDT),  4,4’dichlorodiphenyltrichloroethane (p,p’-DDT), metoxichlor, dieldrin and aldrin in the flesh, liver, bones and gills of five commercially available  species (Bagrusbayad, Clariasanguillaris, Latesniloticus, Hetorosisniloticus, and Auchenogianis occidentals)within River Benue in Vinikilang,  Adamawa State, Nigeria.The sample collection and preparation were carried out using standard procedures. The concentration of all the analytes in  the samples were analyzed using Gas Chromatography-ion trap Mass Spectrometer with optional Msn mode. The study revealed that all the  organochlorine pesticides analyzed (p,p’-DDT, o,p’-DDE, p,p’-DDD, o,p’-DDD, Metoxichlor, dieldrin and aldrin), were detected in all the studies fish  samples. Highest levels of these pesticides were observed in the gills of Auchenogianis occidentals compared to other tissues. This study revealed  that pesticide residue levels in the fish samples studied were lower than the maximum residue limits (MRLs) and acceptable dietary intake (ADI),  with the exception of dieldrin and aldrin which were higher than the WHO and FAO set maximum residue limit (MRL) of 0.2 mg/kg and the  Acceptable Daily Intake values (ADIs) of 0.0001mg/kg. Thus, the use of these pesticides to control pest by farmers within the study area with little or  no knowledge must be checked through adequate control of the trade and use of pesticides and the enforcement of appropriate sanctions.