A multi-residue method for determination of 36 endocrine disrupting chemicals in human serum with a simple extraction procedure in combination of UPLC-MS/MS analysis

Much attention has been paid to endocrine disrupting chemicals (EDCs) due to their widespread presence in various environmental matrices, and endocrine disrupting potential even at low concentrations. However, little is known about the multiple EDCs exposure to human and related adverse effects on health, which warrants a multi-residue method for simultaneous determination of EDCs in human samples such as serum. In this study, we developed and validated a novel method for determination of 36 EDCs (8 bisphenols, 7 parabens, 2 anti-microbials, 5 benzophenones, and 14 phthalate metabolites) in human serum with ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). Two extraction methods (liquid liquid extraction (LLE), and LLE coupled with solid phase extraction (SPE) clean-up) were compared, and eleven solvents and two SPE cartridges were optimized for extraction and clean-up procedure, respectively. Recoveries of target compounds spiked in human serum at three levels of concentrations (0.5, 2.5 and 10 ng/mL) ranged from 45.8% to 120%, and the relative standard deviations (RSDs) were lower than 20%. The linearity of the labeled dilution calibration curve was good with correlation coefficient ranging from 0.995 to 0.999, and the limits of quantification (LOQs) were between 0.002 and 0.532 ng/mL. Low RSDs of intra-day (0.1-12.7%) and inter-day (0.2-13.3%) revealed the accuracy and precision of the quantification. The method was successfully applied to determine the target EDCs in human serum samples from 14 randomly selected individuals. The developed method is a promising method for routine measurement of EDCs in human serum.