Determination And Risk Analysis Of Organochlorine Pesticide Residues In Astragalus

Astragalus is one of the most commonly used traditional Chinese medicine materials in daily life,and usually used for medical supplies and health food.With the increasing consumption of astragalus in recent years,the existence of its security risks has gained more and more attention.The dominated safety hazards of astragalus is pesticide residues in vivo,especially organochlorine pesticide residues.Organochlorine pesticide was one of the most widely used in the prevention and control of crop pests.It could still been detected in traditional Chinese medicine materials due to factors as long history,long half-life,large amount of use,difficulty to degradation and etc.With the strengthening of the safety awareness of traditional Chinese medicine materials,the standard of organochlorine pesticide residues become more and more strictly.In this study,the content of 9 organochlorine pesticide residues?alpha-BHC,beta-BHC,gamma-BHC,Delta-BHC,PPI-DDD,OP'-DDT,P'DDT,PCNB?in 30 Astragalus samples from 10 provinces was analyzed by GC-ECD.A more rapid and efficient analysis and detection method was established and health risk analysis of pesticide residues was carried out according to the EPA system.The main findings are as follows:1.The traditional Qu ECHERS method is optimized and the pretreatment method of sample is determined.The extraction and purification conditions were optimized,and the purified samples were clarified by using formic acid-N-hexane as the solvent,0.600 g sodium chloride?NaCl?and magnesium 1.20 g wushui?MgSO₄?as the salt for water removal,40.0 mg octadecyl?C18?and 40.0mg ethyldiamine-N-propylsilane?PSA?as the purification agent.2.Astragalus is used as experimental sample,established the method of the measurement of the 9 organochlorine pesticide residues in Astragalus with the application of GC-ECD detector analysis.and quantified by external standard method.The results showed that 9 kinds of organochlorine pesticide residues have been separated and qualitative sufficiently.The correlation coefficient?r²?of the detection method was more than 0.997 in the linear range of1.00-200?g·L^-1,and the limit of detection?LOD?was 0.500-5.00?g·L^-1,and the limit of quantity?LOQ?was1.50-20.0?g·L^-1between 0.997-0.999.?RSQ?is less than 8.46%,which indicates that the method get pretty well sensitivity and precision.The recovery rate of astragalus was studied by this method.The recoveries of 9 kinds of organochlorine pesticides at the addition of 200?g·L^-1 were 90.3%-118%,which satisfy the requirement of pesticide residue detection.3.The method was used to detect the contents of 9 kinds of organochlorine pesticides from ten provinces in 30 copies of Astragalus.The results showed that?-BHC,PP'-DDD and PP'-DDT were not detected in all the 6 copies of Astragalus.And the results showed that the total content of four kinds of benzenehexachlorides are less than 200?g·kg^-1,the total content of four kinds of dichlorodiphenyltrichloroethanes are less than 200?g·kg^-1,and the content of pentachloronitrobenzene is less than 100?g·kg^-1,which in accordance with the standard of pesticide residues of traditional Chinese medicine materials in"China Pharmacopeia".Through the risk assessment,it was found that the non-carcinogenic risk of all samples?HI?was very low and the risk of cancer?R?was very low.Experimental results showed that the Astragalus meet the national safety standards,reached to edible and officinal standard,it could be used assured.