Solid phase extraction of pesticide residues in water samples: DDT and its metabolites

Solid phase extraction (SPE) cartridge embedded with octadecyl C₁₈ chain bounded to silica particles were used for the isolation and trace enrichment of pesticides from water samples collected from cotton, rice growing and municipal areas. The eluents were analyzed with high performance liquid chromatography (HPLC) using methanol (100%) as mobiles phase at different UV-Visible wavelengths. DDT and its metabolites were found in all areas but were not present in all samples. Concentration of pesticide residues varies from sample to sample and was in the range of 0.017-1.06 ng ml^-1. Overall, recoveries ranged from 84%-91% for all target pesticides.