药物饲料添加剂杆菌肽耐药性风险评估

Risk Assessment of Bacitracin Resistance as a Medicated Feed Additive

本研究旨在为监管部门制定动物源细菌耐药风险管理措施提供理论依据。利用2014年国民体质监测数据、第五次中国总膳食研究数据和欧洲药品管理局官方网站数据,采用抗菌药物风险评估模型,对中国居民经动物性食品摄入杆菌肽的耐药性风险进行点评估。用估算每日摄入量作为杆菌肽膳食暴露量,用危害指数(HQ)进行风险特征描述,反映杆菌肽耐药对人体健康损害的风险等级。结果表明,危害识别得杆菌肽经口毒性极低,但肠球菌、产气荚膜梭菌等致病菌已对杆菌肽产生耐药性,耐药基因可转移至人体肠道菌群。经危害特征描述可知,杆菌肽毒理学每日允许摄入量(ADI)为0.055 mg/(kg·BW),微生物学ADI为3.9μg/(kg·BW)。暴露评估发现,中国居民中2~7岁人群杆菌肽的膳食暴露量最高,女性通过摄入乳类的杆菌肽膳食暴露量高于男性。2~7岁人群中,杆菌肽的膳食暴露量以乳类贡献最大,8岁以上人群杆菌肽的膳食暴露量以肉类贡献最大。风险特征描述发现,中国居民中通过摄入肉、蛋、乳等动物性食品的杆菌肽耐药性风险,2~7岁人群HQ分别为男性1.4901、女性1.4121;其他年龄人群均<1。不确定性分析发现,结果不确定性源自缺乏动物性食品杆菌肽残留量监测数据、权威数据发布的滞后性、未考虑水产品等因素。综上动物性食品中药物饲料添加剂杆菌肽耐药性风险,2~7岁人群为高风险,其他年龄段人群为中等风险。针对杆菌肽的耐药性风险,必要时修订动物性食品中杆菌肽的最大残留限量,同时加强对进口动物性食品的杆菌肽耐药性风险管理。

The aim of this study was to provide theoretical basis for regulatory departments to formulate risk management measures for bacterial resistance of animal origin.The point assessment method was applied to assess the risk of bacitracin resistance in animal origin foods of Chinese residents,according to the model of risk assessment analysis,based on the data from the monitoring report of the citizen’s physiques in China in 2014,the fifth Chinese total diet study and the official website of European Medicine Agency.Dietary exposure to bacitracin was calculated by estimated daily intake,and hazard quotient(HQ)was used in risk characterisation to indicate risk level of health damage exposed to bacitracin.Firstly,through the way of hazard identification,the toxicity of bacitracin by oral ingestion was very low.But the pathogenic bacteria such as Enterococcus and Clostridium perfringens had developed resistance to bacitracin,with the resistance genes easily transferring to the human intestinal flora through bacteria commonness.Secondly,the hazard characterization indicated the toxicological ADI was 0.055 mg/(kg·BW),and the microbiological ADI was 3.9μg/(kg·BW).Thirdly,exposure assessment showed that the maximum dietary exposure of bacitracin was in 2 to 7 age group among Chinese residents.And that of women through intake of dairy products was higher than men.Among 2 to 7 age group,dairy products contributed most to the dietary exposure of bacitracin,while meat was the largest contributor above 8 years old.Fourthly,risk characterization hazard quotient was 1.4901 for males and 1.4121 for females among Chinese residents aged 2 to 7 by calculation,and<1 among other age groups.Finally,the uncertainty analysis showed that the lack of monitoring data of bacitracin residues in animal foods,the lag of authoritative data collection and release,the absence of consumption data of aquatic products brought uncertainty to the results.In total,the risk of bacitracin resistance as a medicated feed additive through animal foods exposure was high in children aged 2 to 7 and moderate in other age groups.The maximum residue limit standard should be revised appropriately and risk management of bacitracin resistance need to be strengthened in imported animal foods.