气相色谱-质谱联用检测烟草中拟除虫菊酯类农药残留量的不确定度评定
Uncertainty Evaluation for Determination of Pyrethroid Pesticide Residues in Tobacco by Gas Chromatograph-Mass Spectrometry
袁芳 1刘小艳 2姚明月 2肖新生 2李佳颖 1陈馨3
作者信息
- 1. 湖南省烟草公司永州市公司 湖南永州 425100
- 2. 湖南科技学院化学与生物工程学院 湖南永州 425199
- 3. 湖南省烟草公司永州市公司道县分公司 湖南永州 425300
- 折叠
摘要
依据行业标准YC/T 405.3-2011,采用气相色谱-质谱联用对烟草中拟除虫菊酯类农药的残留量进行了不确定度评定,通过建立测量模型,识别和量化实验过程中的不确定度来源,接着对各不确定度分量进行合成和扩展,最终得出 6 种农药的实际检测结果.结果表明,影响不确定度的主要因素为标准溶液配制、标准曲线拟合,其次为测量重复性和样品制备,回收率对不确定度的影响相对较小;在 95.45%置信区间时,取包含因子 k=2,烟草中氟氯氰菊酯、氯菊酯、高效氯氟氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯的检测结果及扩展不确定度分别为(0.481 0±0.040 2)、(0.466 0±0.039 7)、(1.035 9±0.102 4)、(1.014 7±0.101 2)、(0.940 0±0.075 9)、(0.949 0±0.077 0)mg/kg;标准溶液配制对 6 种农药引入的不确定度分量贡献率为 40%～60%,而样品制备和回收率对 6 种农药引入的不确定度分量贡献率普遍较低,为 2%～9%.为了减小不确定度应该配制合适浓度的标准溶液,优化样品制备过程中的前处理步骤,提高人员的实验操作能力,定期对仪器及量具进行维护.
Abstract
According to the industry standard YC/T 405.3-2011,the uncertainty of pyrethroid pesticide residues in tobacco was evaluated by using gas chromatography-mass spectrometry.By establishing the measurement model,identifying and quantifying the sources of uncertainty during the experiment,and then synthesizing and expanding the components of uncer-tainty,the actual test results of six pesticides were finally obtained.The results showed that the main factors affecting the un-certainty were standard solution preparation and standard curve fitting,followed by measurement repeatability and sample preparation,and the recovery rate had relatively little effect on the uncertainty.With a confidence of 95%and a coverage fac-tor of k=2,the measurement results and expanded uncertainty of cypermethrin,permethrin,beta-cyhalothrin,cypermethrin,valerthrin,and deltamethrin in tobacco were(0.481 0±0.040 2),(0.466 0±0.039 7),(1.035 9±0.102 4),(1.014 7±0.101 2),(0.940 0±0.075 9),(0.949 0±0.077 0)mg·kg-1,respectively.The contribution rate of standard solution preparation to the un-certainty component of the six pesticides ranged from 40%to 60%.However,the contribution rate of sample preparation and recovery to the uncertainty component of the six pesticides was generally low,ranging from 2%to 9%.It is necessary to pre-pare the standard solution at an appropriate concentration,optimize the pre-treatment steps in the sample preparation process,improve the experimental operation ability of personnel,and maintain the instrument and measuring tool regularly to reduce uncertainty.
关键词
烟草/不确定度/气相色谱-质谱联用/拟除虫菊酯类农药Key words
tobacco/uncertainty/gas chromatograph-mass spectrometry/pyrethroid pesticides引用本文复制引用
基金项目
湖南省烟草公司永州市公司 2022年度烟叶科研项目计划(永烟技[2022]17号)
出版年
2024
NETL
NSTL
万方数据