残留杀虫剂在蔬菜上的衰减与去除的研究

探索农药在蔬菜上的分布、衰减的规律、半减期的计算以及残留杀虫剂的清除方法。实验证实 :蔬菜上杀虫剂的衰减符合化学一级反应动力学的公式 ,其半减期 ,可以用回归方程计算 ,也可以用本文推导的简便的公式计算 ,结果差异不显著。杀虫剂在蔬菜上的半减期 ,是安全使用农药和卫生监督的重要指标之一。喷洒在菜叶上的杀虫剂 ,其总体的衰减虽然符合一级反应公式 ,但杀虫剂在菜叶表面和内部之间的分布却与其总体的消失不一致。随着时间的延长 ,表面的杀虫剂逐渐向蔬菜内部转移 ,叶面上附着的残留杀虫剂的消失 ,却似成一复杂的指数曲线。用非离子型的清洗剂对残留杀虫剂的洗除率较清水为高 ,但也只能洗脱附着于菜叶表面的部分。吸收到蔬菜内部的杀虫剂却难以清除

Study on the degradation of residual insecticides on and in the vegetables and washing off method

The degradation of residual insecticide in the vegetables is according to the first order of chemical dynamitic reaction. The half life of insecticide on/in the vegetable can be calculated through a series sampling and analysis the residual amount to obtain a regression equation or by a simplified equation. Although the total amount of residual insecticide degraded according to the first order of chemical dynamitic reaction, the lost of the partial insecticide which absorbed in the leaves seems likely according to a more complicated exponent curve which has been described. The adsorbed residual insecticide (on the leaves) was easy washed away. The non ionic detergent is more effect than water. But the absorbed insecticide (in the plant tissue) is hard to wash out.