Research On The Joint Determination Method Of Multiple Pesticide Residues In Sugar Beet And Risk Analysi

Sugar beet is one of the important sugar crops,and a variety of pesticides are used to control diseases,pests and weeds during its growth.If these pesticides are used improperly,they will pose a certain risk of harm to the environment and human health.At present,there are few research reports on the analysis of pesticide residues in sugar beet at home and abroad.Therefore,establishing a simple,fast and sensitive analysis technology for multi-pesticide residue is the key to ensuring the food safety of sugar beet,and it is also the focus of related scientific research work.In this paper,two methods for the combined determination of multi-pesticide residues in sugar beet will be established and applied to the risk analysis of actual samples in the main sugar beet producing areas.The following are the main contents and results of the research:1.An improved Qu ECh ERS method combined with gas chromatography-electron capture detector(GC-ECD)was established for the combined determination of 20pesticide residues in red beet.The effects of temperature-programmed conditions,extraction solvents,and purification methods of chromatography on the detection results were investigated respectively.Under the optimized chromatographic conditions and pretreatment conditions,20 pesticides had a good linear relationship(R~2>0.99),the limits of detection were 0.12μg/kg～0.063 mg/kg,the average recoveries were62.0%～116.5%,and the relative standard deviations were 1.9%～10.9%.The method is accurate,efficient and reproducible.It is suitable for the analysis of various organochlorine and pyrethroid pesticide residues in sugar beet.2.A method with gas chromatography-flame photometric detector(GC-FPD)was established for the combined determination of 15 organophosphorus pesticide residues,which can be applied to the determination of pesticide residues in sugar beet,table beet(red beet)and leaf beet.The effects of temperature-programmed conditions,extraction temperature,and purification methods of gas chromatography on the detection results were investigated respectively.Under the optimized chromatographic conditions and pretreatment conditions,15 pesticides had a good linear relationship(R~2>0.99),the limits of detection were 0.0047 mg/kg～0.0261 mg/kg,the average recoveries were60.3%～120%,and the relative standard deviations were 2.0%～19.3%.The method has simple operation,short analysis time and less organic solvent consumption.It is suitable for the analysis of various organophosphorus residues in sugar beet.3.The established GC-ECD and GC-FPD analysis methods were used to detect pesticide residues in 208 sugar beet samples from three major sugar beet producing areas in China.Then I analyzed the risk of pesticide residues in sugar beets according to the detection results,the detected pesticides with reference values did not exceed the standard.The chronic dietary intake risk quotients were all less than 100%,indicating that pesticides in sugar beets have a low risk of harm to human health.