Study On Detecting Pesticide Multiresidues In Main Kinds Of Forest Foods

Bamboo shoot and mushroom are both traditional export products of our country.Now time more and more person pay attention to the security of forest foods.So established the analysis method of the determination of pesticides multiresidues in forest foods is very important.This article discuss for a new method to detecting 33 pesticides residues(included:organophosphorus, organochlorines,pyrethroids and carbamates etc.) in main kinds of forest foods. The method is based on QuEchERS and GC-MS-SIM.And we also optimize for QuEchERS.Lastly we investigated pesticide residues in main kinds of forest foods,the smples were from Anhui,Beijing,Hebei,etc.The main results were summarized as follow.Firstly,we compare with 3 methods for sample preparation,the 3 method's average recoveries were 32.2%～117.0%,26.4%～110.6%and 71.9%～108.3% respectively.Though the results we choose QuEchERS as the compatiable one for sample preparation,and then optimizing the method as the follow aspects.Extracting time:The average recoveries from bamboo shoot extracted with ultrasonic method by 3,5 and 10min were 8.1%～127.8%,71.9%～111.4%, 61.5%～118.0%respectively,the optimal extracting time was 3 mins.Volume of extracting solvent:The volume of extracting solvent were 10mL,15mL and 20mL respectively,and the average recoveries from bamboo shoot extracted were 71.9%～108.3%,64.1%～146.9%,65.2%～155.3%respectively,the optimal volume of extracting solvent was 10mL.Dosage of PSA:The average recoveries of bamboo shoot purified by added 80,100 and 150mg PSA were 53.1%～135.7%,61.4%～116.7%and 62.0%～102.3%respectively,the optimal dosage of PSA was 80～100mg.Append for 3 consistences in bamboo shoot and mushroom,they were 0.2mg/kg,1mg/kg and 2 mg/kg.The average recoveries were 71.6%～102.9%,72.3%～112.5%and 71.9%～108.3%respectively,and the relative standard deviation of 2.9%～17.1%,0.5%～18.5%,2.2%～15.4%respectively in bamboo shoot.The average recoveries were 70.1%～122.8%,71.9%～113.2%, 72.4%～115.4%respectively,and the relative standard deviation of 2.9%～17.1%,2.0%～17.8%,1.5%～18.9%respectively in mushroom.The LOD for 33 pesticides have a range from 0.0013mg/kg to 0.0125mg/kg,fit to the country's demands. Use Chinese goosebeery,chestnut,and hawkthorn to testify the method's applicability,detect these samples by the optimized method and the results were summarized as follows:The average recoveries of 33 pesticides have a range from 75.1%to 114.1%,and the relative standard deviation of 2.3%～19.2%in Chinese goosebeery,the average recoveries have a range from 76.5%to 112.9% and the relative standard deviation of 2.2%～18.8%in chestnut,the average recoveries have a range from 70.3%to 103.3%,and the relative standard deviation of 1.8%～18.8%in hawkthorn.Lastly,we investigated samples of 33 pesticides contaminated by Anhui, Beijing and Hebei produce on the basis of the optimized method.The result of investigation indicated that chestnut of Hebei province was detected,the pesticide was folpet,concentration was 0.32 mg/kg.