Enantioselective degradation of metalaxyl in anaerobic activated sewage sludge.
Enantioselective degradation occurs frequently for chiral pesticides in field matrices and under laboratory conditions. Metalaxyl is a chiral compound and important fungicide. In this study, the degradation of Rac- and R-metalaxyl under anaerobic conditions was studied. The degradation processes were found to follow first-order kinetics. The degradation of the S-enantiomer (T (1/2) = 2.10 days) was much faster than the R-enantiomer (T (1/2) = 8.44 days). The half-life of the Rac-metalaxyl mixture was 4.05 days, which was higher than the S-enantiomer, but lower than the R-enantiomer. These results confirm the need for emphasizing the importance of examining the fate of the stereoisomers in an environmental system.
Chen
Shengwen
S
School of Urban Development and Environmental Engineering, Shanghai Second Polytechnic University, Shanghai, China. swchen@eed.sspu.cn
Liu
Weiping
W
D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics; D000693:Anaerobiosis; D002851:Chromatography, High Pressure Liquid; D005659:Fungicides, Industrial / Q000737:chemistry / Q000378:metabolism* / Q000493:pharmacokinetics; D006207:Half-Life; D012722:Sewage / Q000382:microbiology*; D013237:Stereoisomerism
D005659:Fungicides, Industrial; D012722:Sewage; C028175:metalaxyl; D000409:Alanine