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Herbicide usage has increased dramatically during the last two decades coinciding with the change in farming practices and increasingly intensive agriculture. This study thus assesses herbicide occurrence in the ground water of Delhi i.e. Atrazine and Simazine herbicide. Liquid-liquid extraction with dichloromethane and methanol as extracting solvents were used. These extracted herbicides were separated and quantified by High Performance Liquid Chromatography (HPLC) with ultraviolet detector. The excellent results were achieved with spiked recoveries of 96.8% and 84.6 % for atrazine and simazine respectively. Analysis shows that the concentration of simazine was higher as compared to atrazine. The results obtained were compared with WHO limit of 0.002 mg/l and USEPA limit of 0.003 mg/l for Atrazine and 0.004 mg/l for Simazine. Highest concentration of atrazine was recorded in the north region of Delhi. Sample from the central Delhi did not reveal contamination from any of the herbicides being monitored. The results indicate that there is need for further work to identify sources and fate of herbicide contaminations. The findings of our investigation contribute to the knowledge of the extent of pollution in the groundwater of Delhi.

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