A multimethod for the determination of 150 pesticide metabolites in surface water and groundwater using direct injection liquid chromatography-mass spectrometry.

Based on the information available on 293 pesticides (herbicides, insecticides, fungicides, biocides, growth regulators) 210 pesticide metabolites were selected for inclusion into a multimethod for the analysis of ground and surface water. With the final method 150 pesticide metabolites can be analysed from groundwater and surface water by direct injection-liquid chromatography-electrospray ionization-tandem mass spectrometry with multiple-reaction monitoring. For most of these metabolites this is the first method published. For all metabolites linear calibration in drinking water was possible, with a lower limit of calibration of 0.1 μg/L achieved for 142 analytes and of 0.01 μg/L for 113 of the analytes. Matrix effects in ground and surface water compared to those in the drinking water were moderate (±20%) for 87% of the analytes. For critical sample/analyte combinations standard addition has to be used for correct quantification. This method allows for an extensive study of the occurrence of previously unknown or undetectable pesticide metabolites in groundwaters and surface waters.