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In the present study, we determined the levels of chlorinated pesticide residues in surfacewater samples collected from the Charsadda district (KPK, Pakistan). SPME-GC-ECD with COMBIPAL CTC autosampler was used for extraction and analysis of 20 organochlorine pesticides in thecollected water samples. For maximum efficiency of the SPME procedure, several parameters werestudied, including the extraction and desorption time of the fiber, solution pH, agitation of samples,and stirring speed, etc. This method showed good liner response, with R2 values in the range of0.9887 to 0.9999 for all pesticides. This method also provided good percent recoveries at 1 µg L−1(87.5to 106.0%) and at 2 µg L−1(88.5 to 109.2%). Lower limits of detection for all 20 chlorinated pesticideswere found to be lower than their maximum permissible contamination levels. Approximately 50%of the surface water samples collected from the Charsadda district were found to be contaminatedwith the pesticides γ-BHC, heptachlor, aldrin and dieldrin, with maximum concentrations of 0.023,0.108, 0.014 and 0.013 µg L−1, respectively. For adults and children, the cancer risk from water dueto contamination by various pesticides ranged from 0 to 33.29 × 10−6. The non-carcinogenic riskfrom each pollutant in the water samples of the Charsadda district was found to be in the order ofheptachlor > aldrin > dieldrin > γ-BHC. However, the pesticides α-BHC, β-BHC, heptachlor epoxide,chlordane, endrin, 4,40-DDD, endrin ketone, 4,40-DDT, endosulfan sulfate and methoxychlor werenot detected in any of the surface water samples of investigated in the present study.