Detection Of Antibiotic Residues In Poultry Eggs And Risk Assessment Of Dietary Exposure In Kunming

Objectives:This thesis aimed to detect antibiotic residues in poultry eggs,to conduct diet survey of egg food for urban people in 3 districts of Kunming,and to assess and analyze the exposure risk of antibiotic residues in people via consuming poultry eggs with the dietary exposure risk assessment model.The research will provide reference for the regulation of antimicrobial use and the protection of food safety.Methods:Major research methods employed in this research are laboratory test and questionnaire survey.Ultra high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)was applied to detect the residues of 7 antibiotic drugs in 513 poultry egg samples,qualitatively and quantitatively.The egg samples were extracted by ethyl acetate and concentrated by rotary evaporator.After solving in 1 mL acetonitrile respectively,filtered(0.22 ?m),the samples were separated on Cosmosil packed column(4.6 mm x 150 mm)with acetonitrile solution of 0.01%formic acid and aqueous solution of 0.01%formic acid as mobile phase in gradient elution.A total of 1118 residents were investigated on their consumption of egg foods.Point estimation,probability estimation and risk assessment were used to assess the exposure risk of antibiotic residues in egg food of urban people in 3 districts of Kunming.UHPLC-MS/MS analysis was conducted with electrospray ionization source and detected in positive ion mode.Analyst(?)Instrument Control Processing Software Version 1.6.2 was employed to analyze total ion chromatogram and mass spectra.The data was entried by using EpiData 3.1,statistical analysis was performed with SPSS 26.0,and risk assessment of diet exposure analysis was conducted by using@RISK 7.6.Results:The analytical method shows a satisfied linear relationship in the scope of 0.01?2.50?g/g,with the correlation coefficients of the method greater than 0.990.In the 93 egg samples,7 classes of antibiotics including ofloxacin,danofloxacin,difloxacin,sulfadimethoxine,sulfamonomethoxine,sulfamethoxypyridazine,sulfamethoxazole were dectected and the positive rate was 18.13%.Among the 7 antibiotics detected,sulfamethoxypyridazine was identified in 30 samples with the highest positive rate of 5.85%,sulfadimethoxine was identified in 3 samples with the lowest positive rate of 0.58%.The detection concentration range of each antibiotic was ofloxacin 0.01?0.37?g/g,danofloxacin 0.06?0.48?g/g,difloxacin 0.05?0.29?g/g,sulfadimethoxine 0.03?0.16 ?g/g,sulfamonomethoxine 0.06?1.00 ?g/g,sulfamethoxypyridazine 0.05?0.37 ?g/g,sulfamethoxazole 0.07?2.48 ?g/g.Among the 7 antibiotics detected,the highest residual concentration was sulfamethoxazole with a median of 0.84 ?g/g,and the lowest concentration was ofloxacin,with the median of 0.02 ?g/g.Among the 1118 urban residents surveyed in Kunming,the daily intake of chicken egg was the highest among all poultry egg types.Among residents surveyed,the median daily intake of chicken egg were 20.00 g/d in the past 3 days and 32.13 g/d in the past 1 month.For chicken eggs,the daily intake of pregnant and lactating women was the highest,with the median of 60.00 g/d.Among male residents aged>60 years,the median daily intake of chicken egg were 40.00 g/d in the past 3 days and 42.84 g/d in the past 1 month.Among female residents aged>60 years,the median daily intake of chicken eggs were 30.00 g/d in the past 3 days and 38.61 g/d in the past 1 month.In the past 3 days,the median daily intake of chicken eggs was 20.00 g/d in other groups.In the past 1 month,the median daily intake of chicken eggs ranged from 25.74 to 34.26 g/d in other groups.Among residents surveyed,the median daily intake of duck eggs,quail eggs,and goose eggs in the past 3 days and the past 1 month were all 0.00 g/d.The estimated daily intake of sulfamethoxypyridazine was the highest among the 7 antibiotics,with the average range of 0.006?0.055 ?g/(kg·bw·d),the P5O percentile range of 0.003?0.024 ?g/(kg·bw·d)and the P95 percentile range of 0.018?0.139?g/(kg·bw·d).The estimated daily intake of antibiotics was higher among residents aged<10 years and pregnant and lactating women than other people.The hazard quotient of sulfamethoxypyridazine was highest,with the average range of 0.12×10-3?1.10×10-3,the P50 percentile range of 0.06×10-3?0.48×10-3 and the P95 percentile range of 0.36×10-3?2.78×10-3 The hazard quotient of 7 classes of antibiotics were far less than 1.Conclusions:Seven classes of antibiotics were detected in poultry egg samples collected in Kunming city.The type and concentration of antibiotics detected in different poultry eggs were different.Two or more antibiotic residues were detected in some poultry eggs.The daily intake of chicken eggs of pregnant and lactating women in Kunming was higher than other groups.The point assessment result of estimated daily intake was higher than the probability assessment result.This study indicated that the exposure of antibiotics in poultry egg food was in the safe range and there was no health risk.We suggest that strengthening the supervision and training of famers in order to guide the proper use of antimicrobials for treatment of poultry diseases and enhancing the monitoring of antimicrobial residues in poultry eggs.Furthermore,we also recommend to establish a complete food safety risk assessment system to prevent food safety risks.