Assessment of Pesticide Residues in Sediments Collected from River Ravi and its Tributaries between its stretches from Shahdara to Balloki Headworks, Pakistan

摘要

Contaminated bed sediments of fresh water bodies have a potentiality of polluting and rendering the water unfit for aquatic life. Though Pakistan has banned on the use of Organochlorine and Nitrogen containing pesticides, but no proper attention is being paid on the continuous monitoring and assessment of these banned pesticides to make sure that these banned pesticides are not in practice. Levels of selected organochlorine and nitrogen containing pesticides residues were assessed in sediments collected from eighteen sampling sites of River Ravi and its tributaries by GC-ECD method. All sediments samples were found contaminated with varying concentrations of pesticides residues, however levels of pesticides were below the tolerance limits suggested in national and international standards. Endosulfan was the predominant organochlorine pesticide residue in all sediment samples, while Carbofuran was found in least amounts as compared with other pesticides. After Degh fall and After Hudiara nulla fall river sampling sites were found severely contaminated while, among tributaries Degh fall and Hudiara drain were found highly severely contaminated with DDT, DDE, Endosulfan and Carbofuran. Constant monitoring programs are needed to be initiated to reform the present situation.