14C-氯氰菊酯农药在“微宇”环境中的迁移、归宿

本文在“微宇”环境中研究~(14)C-氯氰菊酯在玉米-土壤-土壤动物相间的质量平衡、吸收、结合残留、迁移和转化规律。实验结果表明,植物通过根部从土壤中吸收少量氯氰菊酯,并通过叶脉输导,但向上输导能力差,无内吸作用。它在土壤中性质较稳定,被动、植物吸收的药剂,在植物体内主要转化为结合态;在动物中则主要为代谢作用。它在土壤中以酯链断裂为主要降解路线,其次为4′-位置上羟化,再经土壤甲基化作用生成4′-甲氧基代谢物。

The Transport and Fate of 14C-cypermethrin in A Microcosm under the Laboratory Conditions

The aim of the experiments is to study mass balance of 14C~cypermethrin in a close ecosystem by observing metabolism, degradation and distribution of the pesticide. The microcosm was set up in a 30 cm-desiccator with 15 one-week-old maize plants and 15 earthworms (Eiscnia foetida) in the sandy loam soil containing 5.5ppm pure 14C-cypermethrin.The results indicated that cypermethrin residues was absorbed in the maize roots, but very little was to be migrated to the leaves. After two weeks, the mafor product in the maize plants was the bound compounds which contained 81.81%; the armount of metabolic products in the earthworms was 72.40%; parent of cyper-methrin in soil 68.74%. In soil main product 3-phenoxy-benzaldehyde was degraded by splitting of chain easter and 4'-methoxy-compound was formed by hydroxylation and methoxylation at 4'-carbon atom.