SPE-LC-MS-MS determination of phenoxy acid herbicides in surface and ground water

A novel method has been developed and validated for the analysis of six phenoxy acid herbicides (dicamba, 2,4-D, MCPA, dichlorprop, mecoprop and MCPB) in surface and ground waters. After solid-phase extraction on Isolute ENV+, analysis was by LC-MS-MS without using derivatization. The limits of quantitation are from 0.01 to 0.05 mu g L(-1). Average recoveries in method validation (spiking levels: limit of quantitation and 10 times limit of quantitation) ranged from 76.5 to 108.3%, with relative standard deviations of < 13.6%. The method was applied to real surface and ground water samples which gave average recoveries (spiking level: 0.1 mu g L(-1)) ranging from 82.7 to 94.8%, with relative standard deviations of < 19.3%.