Analysing transformation products of herbicide residues in environmental samples

High-performance liquid chromatography (HPLC) methods were developed for th e optimised determination of five herbicide residues (dichlorprop, isoprotu ron, mecoprop, metsulfuron-methyl and 2,4,5-T) and major metabolites. These compounds represent important groups of herbicides and several residues ha ve been found as contaminants in groundwater. The methods make it possible to study these herbicides and several transformation products through simul taneous detection and quantification. Culture media as well as cleaned up e xtracts from sediment and groundwater can be analysed. Using HPLC with UV d etection the general limit of quantification was 1.8 ng injected correspond ing to a detection limit of 1-2 mug/l when analysing a cleaned up extract f rom a 20 mi water sample. The method was verified by analysing herbicide re sidues in groundwater collected from a wetland area. Cleaning up 20 mi grou ndwater with a residue level of 25 mug/l the general recovery was within 58 -82%. (C) 2001 Elsevier Science Ltd. All rights reserved