Dynamics Of Degradation And Analysis Of The Safety Use Of Organophosphorus Pesticides On Vegetables

The quality of vegetables was concerned by people lately with the development of society,the improvement of people's living standards and health awareness . In recent years China's exports of vegetables are often returned because of pesticide residues exceed the standard,in addition, vegetable -poisoning incidents often occurred in our country , the quality and security of vegetables have gradually become the focus of the people,so the detection of pesticide residues on vegetables and the study of degradation of common pesticides become particularly important.In view of previous studies on organophosphorus pesticide residues,the study samples have not representative because environmental samples have not been systematically analyzed,so it is difficult to determine the interference of the experimental results caused by uncertainty reasons in the environment.In this paper, soil, environmental water and three kinds of vegetables were selected from the vegetable production base as samples were purified and pre-treatmented. methamidophos, dimethoate, chlorpyrifos, methyl parathion was added to the treatment solution of environmental water samples, soil samples, vegetables separatly,by which the feasibility of the experiment was proved. Degradation dynamics of recommended concentration of methamidophos, dimethoate, chlorpyrifos, methyl parathion on celeries, lettuces, potatoes and tomatoes were researched by GC-MS, the dynamics of degradation were researched when certain pesticides were sprayed in different vegetables ,the changes of safety interval days were identified when different concentrations of a pesticide were sprayed on different vegetables,and the changes of safety interval days were studied when the times of pesticides spraying were changed.In this paper, reliable experimental datas were provided for the safe use of pesticides of national standards,the specific theoretical datas were provided for the regulators of the quality of vegetables and agricultural sectors in guiding the farmers how to produce low toxicity, low residual pollution-free vegetables,so it has great practical significance.