Study On Human Exposure Risk Assessment And Transfer Of Multi-pesticide Residues In Honeysuckle

Objective:Honeysuckle with outstanding medicinal and edible functions has attracted increasing world-wide attention.However,the inevitable use and residue of pesticides has caused serious threaten to its quality and safety and human health during the process of planting,growing,harvesting and storage.In this study,a UFLC-MS/MS approach was first developed for simultaneous determination of 23 pesticides in real honeysuckle and tea infusion,which can realize sensitive and rapid detection of pesticide residues in honeysuckle and tea infusion.Then,the validated method was applied for commercial honeysuckle samples,the long-and short-term exposure risk to these pesticides via intake of honeysuckle was assessed through calculating the chronic hazard quotient and acute hazard quotient.Finally,considering the high levels of multi-pesticide residues in honeysuckle,we investigated the inherent regularity of pesticides’transfer behavior,and the effects of pesticide’s physical-chemical para-meters on its transfer behavior under different tea brewing conditions.This study provides reference and basis for establishing the maximum residue limit of pesticides and guides the proper use of honeysuckle.Methods:Firstly,by optimization the liquid phase and mass spectrometry conditions,a modified QuEChERS sample preparation based UFLC-MS/MS approach was developed for simultaneous determination of 23 pesticides in real honeysuckle samples and tea infusion.Then,the validated method with fascinating sensitivity and selectivity was applied in 64 batches of commercial honeysuckle samples.the long-and short-term exposure risk to these pesticides via intake of honeysuckle was assessed through calculating the chronic hazard quotient and acute hazard quotient.Finally,considering the high levels of multi-pesticide residues in honeysuckle,the residual behavior of 23pesticides from honeysuckle into tea infusion was investigated under different brewing conditions:infusion duration,infusion repetitions and covered up or uncovered up.And according to the effects of pesticide’s physical-chemical parameters on its transfer behavior,an predict model for transfer prediction was developedResults:1、Human exposure risk assessment of pesticide residues in honeysuckleIn this study,a modified QuEChERS based UFLC-MS/MS approach was developed for simultaneous determination of 23 pesticides.An orthogonal experimental design was introduced for optimized the crucial parameters for highly-efficient extraction of diverse pesticides in honeysuckle.After method optimization,the 23pesticides were effective extracted by using acetonitrile containing 1%（v/v）acetic acid,followed by clean-up with 75 mg anhydrous MgSO₄,20 mg PSA and 100 mg GCB as the adsorbents.Under the above-optimized conditions,Great linear relationships between peak area and concentration of the 23 pesticides were observed with R² of0.9967-0.9999 in their wide concentration ranges.The proposed UFLC-MS/MS method exhibited high sensitivity with LODs of 0.06-10μg/kg,along with LOQs of0.25-20μg/kg,respectively.The average recoveries were in the range of 70.80–119.20% with RSDs from 0.9–13.3%.RSDs of 0.42%–13.12%indicated good repeatability and precision.Then,the validated method was applied in 64 batches of commercial honeysuckle samples,the results showed18 pesticides（78.26% of the pesticides investigated,18/23）out of the 23 targets were detected in honeysuckle samples.Of them,carbendazim,thiophanate-methyl,metalaxyl and chlorpyrifos were detected in all the 64 samples.The incidence rate of officially-banned pesticides was 93.75% with contents from0.0097 to 0.22836 mg/kg.Imidacloprid,carbendazim,thiophanate-methyl and acetamiprid presented high residue levels more than the maximum linear concentration point of 0.8 mg/kg（200 ng/m L）.Considering the possible health risks related to pesticide residues,risk assessment of human exposure to pesticides via intake of honeysuckle was evaluated,the long-/short term risk estimation in the range of0.00005-2.72081%,0.02-6.32075%,respectively.Along with the cumulative risk for all the tested pesticides were all less than 10%,indicating that the short-and long-term and cumulative risk of human exposure to pesticides via intake of honeysuckle were all negligible.2、Effects of pesticide’s physical-chemical parameters on its transfer behaviorIn this study,a QuEChERS coupled to UFLC-MS/MS method for the detection of23 pesticides in honeysuckle tea infusion was established.The best purification conditions for the sample preparation was:20 mg PSA,20 mg GCB,and 300 mg Mg SO₄.Good linear range of 23 pesticides was observed,the correlation coefficient R² were all greater than 0.9905.The LODs and LOQs of 23 pesticides were 0.004-2.5μg/kg and 0.008-5μg/kg,respectively.Good repeatability was obtained with RSD of0.72-11.55%.Based on the above-established method,the residual behavior of 23 pesticides from honeysuckle into tea infusion was investigated under different brewing conditions:infusion duration（5 min;10 min;20 min;30 min;60 min）,infusion repetitions（T1,T2,T3）and covered up or uncovered up.It was found that pesticide transfer was largely consistent with the comprehensive ranking of the water solubility and the Log Kow value of the 23 pesticides,and different tea brewing conditions have a greater impact on the pesticide transfer.Pesticides with larger water solubility and smaller Log Kow value,the transfer increased as the infusion duration increases.However,for pesticides with small water solubility and large Log Kow value,the transfer decreased gradually.At the same time,infusion repetitions have a greater impact on the transfer of pesticides.The pesticide transfer after the second tea infusion T2 is less than 50% of the first tea infusion,and the third tea infusion T3 only accounts for the only 20% of the T1.When uncovered up,the transfer of the all pesticides were significance lower than that of being uncovered up.The predict model of physical-chemical properties and the transfer indicated that the water solubility and Log Kow have a large correlation（R²>0.5）with the transfer of the pesticides,while the vapor pressure and Henry’s constant have a small correlation with the transfer of the pesticides.More importantly,the correlation is better between the water solubility and Log Kow value with the pesticide transfer in the case of uncovered up,indicating that uncovered up can largely reflect and predict the change model of the pesticide transfer.Conclusion:1、In this study,the pretreatment method of complex matrix honeysuckle samples was optimized through an efficient and economical orthogonal experiment design,and a highly sensitive,fast and simple method for detection multi-pesticide residues in honeysuckle was successfully established.The long-and short-term exposure risk to these pesticides via intake of honeysuckle was assessed through calculating the chronic hazard quotient and acute hazard quotient,indicating negligible short-and long-term risks to human health.This study provides a robust platform for multi-pesticides monitoring in honeysuckle to promote the proper use of pesticides and protect the consumers from potential health risks associated with pesticide residues in honeysuckle.2、In this study,a sensitive and rapid detection system for multi-pesticide residues in honeysuckle tea infusion was established,the residual behavior of 23 pesticides from honeysuckle into tea infusion was investigated under different brewing conditions.And an predict model for transfer prediction was successfully developed.This study provides useful information for risk assessment and establishing the maximum residue limit of pesticides in honeysuckle.Furthermore,providing theoretical guidance for related Chinese herbal tea,such as rose,chrysanthemum,and other herbals in tea brewing conditions.