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

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.