Studies On Residue Situation And Diet Exposure Risk Assessment Of Pesticides In Lonicere Japonicae Flos

Lonicere Japonicae Flos is one of the most widely used Chinese herbal medicines, possessing wide pharmacological actions,such as clearing heat and removing toxicity, antiphlogosis,anti-bacteria and anti-virus.Currently,medicine mainly comes from artificial cultivation.Because pests and diseases appear frequently during planting, pesticides are necessary to use and abuse appears now and then.To ensure the safety of the products,it’s important to provide effective supervision and control on the basis of getting a full picture of residual dynamics of pesticide in Lonicere Japonicae Flos.In this study,123 pesticides and metabolites selected for Lonicere Japonicae Flos targeted were monitored on the basis of field research and literature research;3 exclusive methods determining pesticide residues in Lonicere Japonicae Flos were established;The residue situation and diet exposure risk assessment of pesticides in Lonicere Japonicae Flos were discussed for the first time.And specific suggestions were presented to provide evidence for the control of pesticide residues in Lonicere Japonicae Flos.The results were as follows:1.Three methods were established in the study,which were the method determining 37 organochloride and pyrethroid pesticides by GC-ECD,the method determining 54 organophosphorus by GC-FPD and the method determining 123 pesticides selected by GC-MS.The average recoveries of 3 methods were 80.1%-92.7%,90.6%-94.8% and 85.5%-104.1% with most RSD less than 15%,which accorded with the requirement of pesticides determination.The method by GC-MS had many advantages such as simpleness and high sensitivity which is suitable for detection of pesticides in Lonicere Japonicae Flos.The other two selective methods could be auxiliary and verified to retain the accuracy of the results.2.The established methods have been applied for 60 samples of Lonicere Japonicae Flos collected from 6 major distribution channels(GAP bases,drugstores,hospital pharmacies,herbs INCs,prepared chinese medicine enterprises and medicinal materials markets) in 14 different provinces.The result showed that for all the samples,at least one pesticide residue was found in each one and 41 pesticides were detected in all samples. Among the detectable pesticides,11 ones were organophosphorus,9ones were organochlorine,7 ones were pyrethroid,4 ones were carbamate,while the others were triazole,amides and so on.3.The diet exposure risk assessment of pesticides in Lonicere Japonicae Flos were discussed using point evaluation for the first time.The results of risk were described by values of ADI% and %ARfD. The smaller values of ADI%(%AR/D) means the lower risk.The risk is acceptable if values of ADI%(%ARfD) are less or equal to 100%, otherwise it means that unacceptable risk exist.The results showed as follows:Evaluating the risk of chronic dietary intake:the values of%ADI ranged from 6.66×10-6% to 3.27%and the values of omethoate and triadimenol were above 1%. Evaluating the risk ofacute dietary intake:the values of %ARfD ranged from 1.15×10-3% to 15.7% and the values of chlorpyrifos,fipronil,triadimenol,carbofuran,bifenthrin and cyhalothrin were above 1%.All the values of ADI% and %ARfD were less than 100%,which meant that whether the risk levels of chronic dietary intake or acute dietary intake were all acceptable.But the acceptable risk do not mean there is no risk.The pesticides whose %ADI or %ARfD is above 1% may possess potential risk,so more attention should be paid to these ones during the control of pesticide residues.The risk of some pesticides such as omethoate was relatively high,because the relevance ratio,detectable level and virulence are all high.Though the virulence of some pesticides such as triadimenol are low, the risk of them were also relatively high,because the relevance ratios of them were high and detectable level of several samples were very high.Some pesticides such as phorate are highly toxic,but the risk of them were completely low,since the relevance ratio and detectable level of them were both low.The relevance ratio of cypermethrin was highest of all the pesticides, while the detectable levels of it were low overall, so whether the risk levels of chronic dietary intake or acute dietary intake of it were both low.Therefore,the relevance ratio and detectable level can not be used as a basis for risk identification. The risk assessment should be used to identify risks.The study has important practical value,since specific suggestions were presentedfor the control of pesticide residues and some evidence were provided for the establish of MRLs in Lonicere Japonicae Flos on the basis of studies on residue situation and diet exposure risk assessment of pesticides.