Abstract:

An analytical method was established for simultaneous determining butachlor and clomazone residues in cotton and soil. Samples were extracted with acetonitrile, cleaned up by passing through an aluminum oxide (neutral) column, determined by reversedphase HPLC with an ultraviolet detector. When the sample was spiked at 0.05-1.0 mg·kg-1, the average recovery varied from 88.78% to 99.52% (RSD 0.49%-2.09%) for butachlor and 85.57% to 101.2% (RSD 0.7%-2.4%) for clomazone. The lowest detection limit for butachlor and clomazone was 5.×10-10 and 1.×10-9 g, respectively. The lowest detectable concentration was 0.5 mg·kg-1 in cotton seeds and soil. The proposed method met the demands of pesticide residue analysis. The degraded dynamic in cotton leaves and soil indicated that the half lives of butachlor were 2.4 and 2.3 days, and the half lives of clomazone were 2.4 and 2.3 days. The final residues of butachlor and clomazone in soil and cotton seeds were less than 0.5 mg·kg-1．

Key words: butachlor, clomazone, cotton, soil, residue, simultaneous determination