Determination of Ten Kinds of Monohydroxylated Polycyclic Aromatic Hydrocarbons in Human Urine by Supported Liquid Extraction Followed by Liquid Chromatography-Tandem Mass Spectrometry
Abstract The monitoring of urinary monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) can be used for risk assessment of human exposure to polycyclic aromatic hydrocarbons (PAHs). In this work, we developed a novel pretreatment method based on supported liquid extraction (SLE) for determination of 10 kinds of OH-PAHs by liquid chromatography- tandem mass spectrometry (LC-MS/MS). Urine samples were extracted with a mixed solvent of dichloromethane/n-hexane (3:7, V/V) by an SLE clean-up using a diatomaceous earth minicartridge. The results indicated that the developed pretreatment procedure gave good recoveries, while also significantly reducing the interference of the biological matrix. At three concentration levels (10, 50 and 100 μg L−1), the recoveries of 10 kinds of OH-PAHs ranged from 88.5% to 120.9%, and the repeatability ranged from 1.6% to 8.1%. The limits of detection ranged from 0.06 μg L−1 to 0.30 μg L−1, and the limits of quantification were between 0.2 μg L−1 and 1.0 μg L−1. This method was finally successfully applied for the determination of OH-PAHs in urine samples collected from primary school students in Guangdong. The results showed that 2-hydroxynaphthalene was the dominant compound, with a highest concentration of 4.83 μg L−1.