Gas chromatographic mass spectrometric determination of alachlor and its degradation products by direct aqueous injection

A GC-MS method, with direct aqueous injection, has been developed to determine alachlor and its degradation products in water. The method was optimized to give the following conditions: injection with splitless mode, injection port with silanized-glass reverse-cup liner filled with 0.5 cm Carbofrit above the cup; injection temperature of 250 degrees C; and an analytical column with a stationary phase of 5% diphenyl and 95% dimethyl polysiloxane and dimensions of 60 m x 0.25 mm x 0.25 mu m The minimum detection limit is 0.05 to 1 mg/l in the GC-MS-SIM mode with variation of peak height less than 5% and 5 to 50 mg/l in the GC-MS-Scan mode for alachlor and its degradation products. (C) 1998 Published by Elsevier Science B.V. All rights reserved.