不同清洗方式对生菜表面农药残留的降解效果

在生菜模拟体系中研究碱性水(pH 10.5和pH 11.5)、臭氧水以及自来水清洗对生菜表面人为污染的敌敌畏、马拉硫磷、乐果、毒死蜱4种有机磷农药的降解效果,采用气象色谱(GC)方法对农药进行定量分析。结果表明:碱性水对生菜所污染的4种有机磷农药均有很好的降解效果;同时,碱性水对4种有机磷农药的降解受溶液的pH值和处理时间的影响,pH值11.5的碱性水效果最好,且降解效果随着农药初始浓度的降低而提高。15 min的碱性水清洗即可取得理想的降解效果。

The Redidues of Four Organophosphorus pesticides on Lettuce with Different Washing Methods

The removal of four kinds of organophosphorus pesticides including dichlovos,malathion,dimethoate,and chlopyrifos by alkaline water(pH 10.5 and 11.5),ozonated water and tap water were investigated in lettuce.The content of residues of pesticides was performed by GC.The results indicated that alkaline water could significantly lower all four pesticides.The pH values,and treatment time influenced the treatment.The alkaline water washing at pH 11.5 performed best.The removal rate increased with the decreased initial concentration of the pesticides.Furthermore,15 min washing was enough for the effective degradation of pesticides.