College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China.
Ecotoxicol Environ Saf. 2010 Nov;73(8):1925-31. doi: 10.1016/j.ecoenv.2010.07.035. Epub 2010 Aug 19.
The effects of (Rac)-metolachlor and (S)-metolachlor on the avoidance behavior, bodyweight change and in vivo enzyme activity of earthworms (Eisenia foetida) were determined and compared in this study. The effects of (Rac)-metolachlor on the enzyme activities of E. foetida and bodyweight were more significant than those of (S)-metolachlor at the same concentrations. In the short term (2 d, 7 d), (S)-metolachlor had faster effects on cellulase and catalase activities of E. foetida. However, in the relatively long term (14 d, 28 d), (Rac)-metolachlor had higher toxic effects on cellulase and catalase activities. The inter-group difference between (Rac)-metolachlor and (S)-metolachlor on E. foetida enzyme activities was the most significant for catalase, and the least significant for cellulase. The test of avoidance behavior shows that earthworms are more sensitive to the stimulation of (Rac)-metolachlor than to that of (S)-metolachlor. The results will help to develop an understanding of the biologically mediated environmental processes of these two herbicides.
本研究旨在测定并比较（Rac）-甲草氯和（S）-甲草氯对蚯蚓（赤子爱胜蚓）回避行为、体重变化和体内酶活性的影响。在相同浓度下，（Rac）-甲草氯对蚯蚓酶活性和体重的影响比（S）-甲草氯更为显著。在短期（2 d、7 d）内，（S）-甲草氯对蚯蚓纤维素酶和过氧化氢酶活性的影响更快。然而，在相对较长的时间（14 d、28 d）内，（Rac）-甲草氯对纤维素酶和过氧化氢酶活性的毒性影响更高。（Rac）-甲草氯和（S）-甲草氯对蚯蚓酶活性的组间差异在过氧化氢酶方面最为显著，在纤维素酶方面则最小。回避行为测试表明，蚯蚓对（Rac）-甲草氯的刺激比（S）-甲草氯更为敏感。这些结果将有助于了解这两种除草剂的生物介导的环境过程。
