Determination of Pesticide Residues in some Agricultural Water Samples by Gas Chromatography

Experiments were conducted to determine 18 pesticide residues in water samples collected from irrigated agricultural farmlands around Mysore city, Karnataka, India. The samples were analysed by gas chromatography consisting of electron capture detector to look for organochlorine pesticides (OCPs) and flame photometric detector for the determination of organophosphorus pesticides (OPPs). Seven pesticides were detected in water samples namely aldrin, dieldrin, a-HCH, b-HCH, g-HCH, 2,4-DDD and endosulfan-1. All the detected pesticides in water samples were in low concentrations. Pond and bore well water samples had no pesticide residues. Among organochlorine pesticides, present in farm water samples, a-HCH and g-HCH were more frequently found followed by 2,4-DDD. No organophosphorus pesticide residues were detected in any water samples.