Abstract
HPLC-DAD and GC-NPD methods were developed to measure medium and highly polar pesticide concentrations in ground and surface waters. To analyse these pesticides in relation with the European Directives, a comparison of different “off-line” solid phase extraction sorbents was carried out. The use of a home-made (SPE) two layers poly(divinylbenzene-co-N-vinylpyrrolidone) - octadecyl-bonded silica (Oasis-C18) cartridge allows to analyse simultaneously medium and highly polar pesticides in natural waters, with quantification limits between 0.03 and 0.05 μg/l according to each pesticide. The recoveries on this sorbent vary between 90 and 105% with R.S.D. below 7% in MilliQ water and between 88 and 115% with R.S.D. below 20%, except for bentazone (26%), in surface water.