| The health of honeybee larvae affects the prosperity of the entire bee colony,and its exposure to pesticide residues only comes from the intake of food.From bee pollen and honey sac content to honeybee larvae food,it needs to go through the processing of bee bread fermentation,honey brewing,and royal jelly secretion by nurse bees.Processing factor is an important indicator to reflect the impact of processing on pesticide residues in agricultural products,and the application of it to assess the dietary exposure of pesticide residues to honeybee larvae food is rarely reported.This paper takes acetamiprid,which is commonly found on rape bee pollen and honey sac content,as the object,to study the residual behavior of the acetamiprid in the process of "bee pollen(honey sac content)-bee bread(honey)-royal jelly",defining the processing factors of acetamiprid residues during honeybee larval food formation,combined with the detection data of the acetamiprid residues in the actual samples of collected bee pollen,bee bread,honey sac content,honey and royal jelly,to verify the application of the processing factor to correct the actual exposure of acetamiprid residues in bee pollen and honey sac content.To provide a scientific basis for the correctly evaluating of the exposure risk of acetamiprid residues in bee pollen and honey sac content to honeybee larvae.The main findings are as follows:1.Confirmation of the method for the analysis of acetamiprid residues in bee pollen,bee bread,honey sac content,honey and royal jellyThe QuEChERS method combined with UPLC-MS/MS was used to confirm the residue analysis method of acetamiprid in bee pollen,bee bread,honey sac content,honey and royal jelly.Acetamiprid had a good linear relationship in the concentration range of 5-500μg/kg,and the correlation coefficient was 0.9991-0.9998;the limit of quantification(LOQ)of the method were 0.58-1.80 μg/kg.At the addition concentrations of 5,50,1000,and5000 μg/kg,the average addition recovery of acetamiprid in bee pollen was 95.46-110.37%,and the relative standard deviation(RSDs)was 5.47-11.07%;the average addition recovery rate in bee bread was 80.79-101.36%,and the RSDs was 5.41-10.43%;the average addition recovery rate in honey sac content was 77.73-93.68%,and the RSDs was3.89-8.49%;the average addition recovery rate in honey was 96.21-105.81%,and the RSDs was 4.81-9.11%;the average addition recovery in royal jelly was 89.43-113.08%,and the RSDs was 1.67-4.53%.The sensitivity,accuracy and precision of the method can meet the requirements of residue analysis of acetamiprid in bee pollen,bee bread,honey sac content,honey and royal jelly.2.Acetamiprid residue behavior and processing factors during bee bread fermentationAiming at the actual process of bee pollen fermented in honeycomb to form bee bread,Study on the digestion dynamics of the acetamiprid residues in rape bee pollen during the fermentation process of bee bread and the final residues in mature bee bread.The semi-field test results showed that the residues of acetamiprid in bee pollen after processing by the honeybees in the nest showed a significant downward trend with the fermentation time,and the digestion rate of acetamiprid in the mature bee bread formed after 15 days of fermentation was 21.43%;At the same time,the digestion rate of acetamiprid in bee pollen without honeybees processing was only 8.10%.The residues of acetamiprid were significantly degraded during bee bread fermentation,and the processing factor of acetamiprid residues during bee bread fermentation was 0.85.3.Acetamiprid residue behavior and processing factors during honey brewingAiming at the actual process of honey sac content brewing in honeycomb to form honey,Study on the digestion dynamics of acetamiprid residues in rape honey sac content during the brewing process of honey and the final residues in mature honey.The semi-field test results showed that the residual acetamiprid in honey sac content after processing by the honeybees in the nest showed a trend of first decreasing,then increasing and then decreasing with the brewing time,and the digestion rate of acetamiprid in the mature honey formed after 7 days of brewing was 21.43%;At the same time,the residual concentration of acetamiprid increased by 4.52% in honey sac content without honeybees processing.The residues of acetamiprid were significantly degraded during honey brewing,and the processing factor of acetamiprid residues during honey brewing was 0.76.4.Processing factors of acetamiprid residues during the formation of royal jellyThe quantitative relationship between the acetamiprid residues in bee bread and honey and the acetamiprid residues in royal jelly was studied in view of the actual process of royal jelly secreted by nurse bees after consuming bee bread and honey.The semi-field test results showed that the average concentrations of acetamiprid in the bee bread and honey fed by the nurse bees for 3 consecutive days were 3386.22 μg/kg and 3290.73 μg/kg,respectively.The final residue of acetamiprid in the royal jelly formed after 3 days of processing by nurse bees was 519.45 μg/kg.The residues of acetamiprid were significantly degraded in the process of bee bead(honey)-royal jelly,and the processing factor of acetamiprid in the process of bee bread(honey)-royal jelly was 0.16.When the acetamiprid residues were only detected in bee bread(3326.18 μg/kg),the final residue of acetamiprid in royal jelly was 18.13 μg/kg,and the processing factor of acetamiprid in the process of bee bread-royal jelly was 0.04;when the acetamiprid residues were only detected in honey(3538.76 μg/kg),the final residue of acetamiprid in royal jelly was 362.90 μg/kg,and the processing factor of acetamiprid in the honey-royal jelly process was 0.12.5.Detection of acetamiprid residues in samples of bee pollen,bee bread,honey sac content,honey and royal jellyThe results of acetamiprid residue detection in actual samples of bee pollen,bee bread,honey sac content,honey and royal jelly for 3 years showed that the detection rate of acetamiprid in 274 bee pollen samples collected was 17.15%,and the residual concentration was 1.6-21.8 μg/kg;the detection rate of acetamiprid in 336 bee bread samples was 23.51%,and the residual concentration was 1.8-347.5 μg/kg;the detection rate of acetamiprid in 251 honey sac content samples was 1.2%,the residual concentration was 3.7-17.8 μg/kg;the detection rate of acetamiprid in 361 honey samples was 12.19%,and the residual concentration was 1.4-134.4 μg/kg;the detection rate of acetamiprid in 23 royal jelly samples was 21.74%,the residual concentration was 1.4-3.8 μg/kg.Based on the 90 th percentile values of acetamiprid residues in the samples of bee pollen(13.28 μg/kg)and honey sac content(17.16 μg/kg),the Predicted Exposure Concentration(PEC)of acetamiprid residues in royal jelly were calculated using the processing factor was 2.05 μg/kg,which was no significant difference with the 90 th percentile value(3.64μg/kg)of the detected concentration of acetamiprid in actual samples of royal jelly.Regardless of the processing of bee larvae food,the calculated PEC of acetamiprid residues in royal jelly was 16.62 μg/kg.It was shown that ignoring the processing factor would overestimate the actual exposure of honeybee larvae to the acetamiprid residues in bee pollen and honey sac content. |
