Chiral Separation Of Fenvalerate And Its Enantiomers In Aquatic Toxicology Research

In this paper, Daphnia magna and Brachydanio rerio were test organisms, and a series of toxicity test were established. A method for chiral separation of four fenvalerate enantiomers was developed by high performance liquid chromatography . The thesis aims to evaluate acute toxicity of fenvalerate and its four enantiomers to Daphnia magna and Brachydanio rerio, and also provides the evaluation standard for environmental organisms.A method for chiral separation of four fenvalerate enantiomers was developed by high performance liquid chromatography on the chiral stationary of cellulose derivative (CHIRALCEL OJ-H). The good resolution was obtained with a mobile phase of n-hexane/1,2-dichloroethane/ethanol (92/6/2, v/v/v) at a flow rate of 0.6mL min-1 under 40℃ 。 The resolutions with over 2.0 for all continuous peaks were shown at the mobile phase conditions. The peak sequence of two pairs of enantiomers , ( R,R)- and (S,S)-isomer were identified by (S,S)-isomer sample and CD Chromatography. And the four peaks was called FN1 , FN2, FN3 and FN4.The effects of added amounts of ethanol in the mobile phase and column temperature were studied.The test evaluates 24h-EC50 and 48h-LC50 of fenvalerate and its four enantiomers for D. magna. Rac-FN, FN1, FN2, FN3, FN4 24h-EC50 values for D. magna in the experimental conditions were 0.41μg/L, 0.86μg/L, 24.84μg/L, 9.53μg/L and 0.49μg/L. The toxicity order was rac-FN>FN4>FN1 >FN3>FN2.Rac-FN> FN1, FN2. FN3> FN4 48h-LC50 values for D. magna in the experimental conditions were 0.28μg/L, 0.25μg/L, 17.77μg/L, 7.14μg/L and 0.18μg/L. The toxicity order was FN4>FN1 > rac-FN > FN3 > FN2.They were all high toxicant on the basis of classification standard of toxicity.The differences of toxicity on the five pesticide were large. FN2 was 60 times more than FN4 according to the 24h-EC50.Even more,FN2 was 100 times more than FN4 according to the 48h-LC50.The test evaluates 96 hours acute toxicity of Fenvalerate and its four enantiomers for Brachydanio rerio. According to the results,LC50 of FN2 was thehighest,the lowest was FN4. FN2 24h-LC50 was 239.9(^g/L. FN4 24h-LC50 was 14^g/L ,the difference was 17 times. FN2 48h-LC50 was 22\3\μg/L. FN4 48h-LC50 was 9.95μg/L,and the difference was 22 times. FN2 72h-LC50 was 209.72μg/L. FN4 72h-LC50 was 5.36μg/L, the difference was 40 times. FN2 96h-LC50 was I93.^g/L. FN4 96h-LC50 was 3.48μg/L,the difference was 55 times. According to the results, the toxicity order of the five pesticide was FN4>rac-FN> FN1>FN3>FN2.