Study On The Detection And Risk Assessment Of Typical Pesticide Residues In Vegetables And Fruits In Nanchong City

With the improvement of people’s living standard in our country,people are increasingly demanding the fruits and vegetables with high quality.Now people pay more attention to the pesticide residue in fruits and vegetables which has become the main quality safe problems.Although relevant functional departments have carried out a lot of pesticide residues detection and supervision on fruits and vegetables,some pesticide residues in fruits and vegetables still exceed the standard according to the report of Nanchong.The purpose of this study is to provide support for the regulatory authorities by assessing the risk of pesticide residues through dietary intake in typical fruits and vegetables based on the test results of typical pesticide residues in Nanchong.A total of four fruits and vegetables(leek,citrus,ordinary Chinese cabbage,cucumber)50 samples each were collected in Nanchong market in 2019-2020.Residue of pesticides involving dichlorvos,phorate,chlorpyrifos(-ethyl),triadimenol,isocarbophos,isofenphos-methyl,Procymidone,methidathi,phosphorous and buprofezin,triazophos,lambda-cyhalothrin,fenbuconazole,cypermethrin,difenonazole were detected and analyzed.The risk assessment of dietary intake on human health was also carried out.The following conclusions are drawn:The laboratory analysis method of pesticide residues is established.The samples were pre-treated by acetylene extraction,solid phase extraction of columns followed by concentrating and then detected by gas chromatography-mass spectrometry.The linearity,quantitative limit,recovery rate and precision of 15 kinds of pesticide residues in four kinds of fruits and vegetables meet the requirements of laboratory determination.The ratio of estimated daily intake(EDI)to daily allowable intake(ADI)of leeks,common cabbage,cucumber and citrus was evaluated,and the results showed that pesticide residues had no significant effect on human health through dietary intake.In view of the current situation of pesticide residues in fruits and vegetables in Nanchong city,the following measures are proposed: improving the metabolism and degradation technology of pesticide residues;optimizing the modern pesticide residues monitoring system;strengthening the management of the origin of agricultural products and market access;improving the level of scientific pesticides use;strengthening the training of farmers,establishing brand management,promoting the construction of demonstration parks and strengthening the production and management of pesticides.