Simultaneous Determination of Multiple Classes of Phenolic Compounds in Human Urine: Insight into Metabolic Biomarkers of Occupational Exposure to E-Waste

A new method using solid-phase extraction (SPE) and high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (HPLC-MS/MS) was established for simultaneously analyzing 35 types of phenolic compounds in human urine samples, including 12 hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs), 16 brominated phenols (BRPs), 5 hydroxyl polybrominated diphenyl ethers (OH-PBDEs), triclosan, and tetrabromobisphenol A (TBBPA). The presence of NH4Ac in mobile phase played a crucial role in achieving good separation of isomers in HPLC-MS/MS analysis. The efficient SPE condition was obtained at pH 2 with a mixture eluent of methanol and dichloromethane. The recoveries of all analytes were 64.5%-143%, 56.2%-135%, and 52.5%-123% for low-, medium-, and high-spiked levels in a urine matrix, respectively, with less than 20% of RSDs of four of repetitive measurements. Moreover, the method was successfully applied to screen the potential urinary biomarker for population exposure to multipollutants from e-waste recycling areas, and 3,4-diBRP, 2,4,5-triBRP, 2,3,4,6-tetraBRP, and 2'-OH-BDE-28 were first tentatively detected in human urine. Specifically, 3,4-diBRP, 2,3,4,6-tetraBRP and, 2'-OH-BDE-28 were only detected in urine samples from e-waste dismantling workers, which should be considered as the urinary biomarkers for occupational exposure. Finally, this developed method will support a more comprehensive health risk assessment for human exposure to multipollutants.