Analysis of organophosphorus pesticides in water using solid-phase extraction followed by high performance liquid chromatography

Abstract

Organophosphorus pesticides in water samples were analysed by solid-phase extraction (SPE) followed by high performance liquid chromatography (HPLC). The optimized condition of reversed-phase octadecyl bonded silica SPE was evaluated from a variety of the isolated parameters such as sorbent mass, volume of solution, type and volume of eluent and pressure of SPE Visiprep vacuum pump. Percent recovery experiments performed for methyl parathion, malathion, profenofos and chlorpyrifos were at 99.06 ± 0.67, 98.04 ± 0.41, 90.78 ± 0.75 and 71.51 ± 0.73, respectively. The method detection limits for methyl parathion, malathion, profenofos and chlorpyrifos were 25,50,25 and 25 ug/l, respectively. Profenofos was detected in twenty-seven agriculture drain water samples at the average level of 0.44 ± 0.07 ug/ml during the crop application period. The chemical structure of profenofos was also confirmed with mass spectral data analysis.