羟基多环芳烃检测结果准确性的影响因素及控制对策

Influencing Factors and Control Countermeasure for the Accuracy of Determination Results of Hydroxy Polycyclic Aromatic Hydrocarbons

目的针对羟基多环芳烃(OH-PAHs)检测过程的影响因素展开研究,使用严格的控制措施,保证检测结果的准确性和有效性。方法依据液液萃取—气相色谱—高分辨双聚焦磁质谱法(LLC-GC-HRMS)测定尿中OH-PAHs,对标准物质、试剂、耗材、实验设备、实验环境及实验人员等环节逐一进行评估。使用标准参考物质进行内部质量控制,通过参加能力验证活动进行外部质量评价。结果在13种OH-PAHs中,9-PHE的氘代内标在使用过程中会发生氘—氢交换,不能用于尿样中9-PHE的定量监测;1-NAP、2-NAP的氘代内标在存放半年后会出现空白干扰;实验人员的吸烟习惯或实验室环境的烟草烟雾污染,会使试剂空白中2-NAP信号显著升高;实验设备及环境中目标物的持续蓄积会带来严重的空白干扰。结论氘代内标的氘-氢交换、实验人员的吸烟习惯和目标物的持续蓄积是影响OH-PAHs检测结果准确性的主要因素,该研究对于尿液中OH-PAHs的准确监测具有重要意义。

Objective To investigate the influencing factors and strict control measures for the determination of hydroxy polycyclic aromatic hydrocarbons(OH-PAHs),and to ensure the accuracy and effectiveness of the determination results.Methods Based on OH-PAHs in urine determined by liquid-liquid extraction-gas chromatography-high resolution dual-focus magnetic mass spectrometry(LLC-GC-HRMS),the authors evaluated the standard substances,reagents,consumables,equipment,environment,and experimenters one by one.The standard reference samplers were used for internal quality control,and proficiency testing activities were used for external quality assessment.Results Among the 13 OH-PAHs,the deuterated internal standard of 9-PHE could not be used for the quantitative monitoring of 9-PHE in urine samples due to deuterium-hydrogen exchange during determination.The deuterated internal standard of 1-NAP and 2-NAP showed blank interference after being stored for half a year.The smoking habit of experimenters or tobacco smoke pollution in the laboratory environment significantly increased 2-NAP signal in the reagent blank.The continuous accumulation of the target compounds in laboratory equipments and environment could bring serious blank interference.Conclusion The deuterium-hydrogen exchange of the deuterated internal standard,the smoking habit of experimenters,and the continuous accumulation of the target compounds are the main influencing factors for the accuracy of the detection result of OH-PAHs,and this study is of great significance for the accurate monitoring of OH-PAHs in urine.