【作者】 汪勇；

【导师】 侯如燕； 郑平；

【作者基本信息】 安徽农业大学 ， 农业硕士（专业学位）， 2022， 硕士

【摘要】 茶是一种广泛消费的饮料,因其各种健康益处和令人愉悦的口味而倍受青睐。茶灌木生长在长期的茶园中,茶园也同样适合杂草持续生长,而这种环境越来越受到除草剂的控制。因此,人们越来越担心茶叶消费者可能会接触到除草剂残留物。草甘膦（Glyphosate,PMG）,具有非选择性、高效、廉价等特点,是目前全球使用量最大的除草剂,草铵膦（Glufosinate ammonium,GLU）属于非选择性、广谱触杀型除草剂,草甘膦与草铵膦均为有机磷类除草剂,而氨甲基膦酸（Aminomethyl Phosphonic Acid,AMPA）是草甘膦的主要有毒代谢产物。据报道草甘膦和草铵膦在茶叶或茶产品中被检测出,甚至存在超标的现象,影响茶叶的质量安全。目前也未有茶叶中草甘膦、草铵膦和氨甲基膦酸的膳食暴露风险评估方面的报道,对其是否对人体健康构成分险尚不明确。目前,草甘膦和草铵膦在茶叶中残留分析的方法种类繁多,且存在前处理过程繁琐,成本较高等问题。针对这些问题,本文建立了茶叶中草甘膦、草铵膦及氨甲基膦酸的HPLC-MS/MS检测方法,并对来自中国11个省的780份样品进行了测定,根据检测结果对茶叶中3种农药的膳食暴露风险评估进行了研究,主要研究结果如下:1)建立了茶叶中草甘膦、草铵膦及氨甲基膦酸的HPLC-MS/MS检测方法,并将该方法与几种现行的净化方法进行了比较,该方法有效地减少了质谱分析过程中由茶基质引起的干扰。2)对建立的HPLC-MS/MS检测方法进行方法验证,草甘膦、草铵膦和氨甲基膦酸的回收率分别为89.6%-115.5%,83.6%-101.6%和82.1%-97.2%,相对标准偏差（RSD）值均低于20%。使用该方法对11个省的780份样品（包括六种茶叶和花茶）进行检测,样品中草甘膦、草铵膦和氨甲基膦酸的检出率分别为9.0%,1.8%和21.2%,草甘膦检出的浓度范围为0.102 mg·kg^-1至2.647 mg·kg^-1,草铵膦检出的浓度范围为0.041 mg·kg^-1至1.428 mg·kg^-1,氨甲基膦酸检出的浓度范围为0.107 mg·kg^-1至3.166 mg·kg^-1。3)根据检测结果对茶叶中草甘膦、草铵膦及氨甲基膦酸进行膳食暴露风险评估。概率估计表明,三种农药残留的第95个百分位数风险熵值分别为2.39×10^-6、7.98×10^-5和1.96×10^-5,远低于可接受的风险水平。膳食风险评估结果表明,喝茶饮料引起的草甘膦、草铵膦和氨甲基膦酸暴露不会对人体健康构成重大风险。更多还原

【Abstract】 Tea is a widely consumed beverage and loved for both its various health benefits and its pleasant taste.Tea bushes grow in long-term tea gardens,which are equally suitable for continued weed growth in an environment that is increasingly controlled by herbicides.As a result,there are growing concerns that tea consumers may be exposed to herbicide residues.Glyphosate（PMG）,which has the characteristics of non-selectivity,high efficiency,and low cost,is currently the most widely used herbicide in the world.Glufosinate ammonium（GLU）is a non-selective,broad-spectrum contact herbicide,both of which are organophosphorus herbicides.Aminomethyl phosphonic acid（AMPA）is the main toxic metabolite of glyphosate.It has been reported that glyphosate and glufosinate have been detected in tea or tea products,and even exceeded the standard,affecting the quality and safety of tea.There is no report on the dietary exposure risk assessment of PMG,GLU and AMPA in tea,and it is not clear whether they constitute a risk to human health.At present,there are many kinds of methods for the analysis of PMG and GLU residues in tea,and there are problems such as cumbersome pretreatment process and high cost.In response to these problems,an HPLC-MS/MS method for the detection of glyphosate,glufosinate and aminomethylphosphonic acid in tea was established in this paper,and780 samples from 11 provinces in China were determined.According to the test results,the dietary exposure risk assessment of PMG,GLU and AMPA in tea was studied.The main research results are as follows:An HPLC-MS/MS method for the detection of glyphosate,glufosinate-ammonium and aminomethylphosphonic acid in tea was established.This method was compared with several current purification methods,which effectively reduce the interference caused by the tea matrix during the analysis.The established HPLC-MS/MS detection method was validated.The recovery rates of PMG,GLU and AMPA ranged from 89.6%to 115.5%,83.6%to 101.6%and 82.1%to 97.2%,respectively.The relative standard deviation（RSD）values were all below20%.This method was used to determine the levels of PMG,GLU and AMPA in 780samples,including six types of tea leaves and a flower tea,from 11 provinces of China.PMG,GLU and AMPA were detected in 9.0%,1.8%and 21.2%of the samples,respectively.The PMG levels ranged from 0.102 mg·kg^-1 to 2.647 mg·kg^-1,GLU from0.041 mg·kg^-1 to 1.428 mg·kg^-1 and AMPA from 0.107 mg·kg^-1 to 3.166 mg·kg^-1.According to the test results,the dietary exposure risk assessment of PMG,GLU and AMPA in tea was carried out.Probability estimates showed that the 95th percentile risk entropy value of the three pesticide residues were 2.39×10^-6,7.98×10^-5 and 1.96×10^-5,respectively,which are far below the acceptable risk level.The risk assessment results showed that exposure to PMG,GLU and AMPA caused by drinking tea beverages poses no significant risk to human health.更多还原