Assessment of Environmental Phenolic Endocrine-Disrupting Chemicals in Human Urine and Their Association with Demographic, Lifestyle, and Metabolic Factors in a Bangladeshi Population Using High-Throughput Solid-Phase Extraction Coupled with UHPLC–Tandem Mass Spectrometry

Abstract

Background: Environmental phenolic endocrine-disrupting chemicals (EDCs) are widely distributed contaminants associated with plastics, food-packaging materials, thermal papers, flame-retardant products, antimicrobial formulations, and a variety of household and personal-care products. Human exposure to these compounds is of increasing public-health concern because several phenolic chemicals can interact with endocrine pathways and may contribute to metabolic, reproductive, developmental, and other adverse biological effects. Biomonitoring of urinary concentrations provides an effective approach for evaluating recent human exposure to these compounds. Nevertheless, simultaneous determination of multiple phenolic EDCs in urine is analytically challenging because of their low concentrations, diverse physicochemical characteristics, biological conjugation, and matrix-related interference. Objective: This study aimed to develop and apply a high-throughput solid-phase extraction coupled with ultra-high-performance liquid chromatography–tandem mass spectrometry (SPE–UHPLC–MS/MS) method for the simultaneous determination of eight environmental phenolic EDCs in human urine from a population in Bangladesh. The investigated compounds were bisphenol A (BPA), bisphenol F (BPF), tetrachlorobisphenol A (TCBPA), tetrabromobisphenol A (TBBPA), bisphenol S (BPS), bisphenol AF (BPAF), bisphenol B (BPB), and triclosan (TCS). The study also establishes an integrated framework for examining potential relationships between urinary phenolic exposure and demographic, lifestyle, and metabolic characteristics. Methods: A total of 64 human urine specimens were analyzed. Urine samples underwent enzymatic hydrolysis followed by high-throughput extraction using a 96-well Oasis HLB solid-phase extraction plate containing 60 mg sorbent per well. A 30% acetonitrile washing solution was used to remove interfering matrix components, followed by methanol elution. Chromatographic separation was achieved using an ACQUITY BEH C18 column (100 × 2.1 mm, 1.7 μm). Detection was performed using tandem mass spectrometry with negative electrospray ionization and multiple-reaction monitoring. Stable isotope-labeled internal standards were incorporated throughout the analytical procedure. Method performance was evaluated in terms of linearity, sensitivity, recovery, precision, matrix effects, and accuracy using certified reference material. Results: The analytical method showed excellent linearity, with correlation coefficients generally exceeding 0.999. Limits of detection ranged from 0.002 to 1.09 μg/L, whereas limits of quantification were approximately 0.007–3.63 μg/L. Mean recoveries ranged from 81.0% to 101.9%. Intra-day relative standard deviations ranged from 0.4% to 19.4%, while inter-day relative standard deviations ranged from 2.5% to 17.8%. In the 64 urine specimens, BPA was detected in 100% of samples, BPS in 96.9%, TCS in 57.8%, TBBPA in 46.9%, TCBPA in 23.4%, and BPF in 21.9%. BPB and BPAF were not detected. Median urinary concentrations were 0.69 μg/L for BPA, 0.086 μg/L for BPS, 1.44 μg/L for TCS, 0.0032 μg/L for TBBPA, and 0.00050 μg/L for TCBPA. Median concentrations for BPF, BPB, and BPAF were zero. Conclusion: The high-throughput SPE–UHPLC–MS/MS method demonstrated strong sensitivity, satisfactory recovery, excellent linearity, and acceptable precision for simultaneous determination of eight phenolic EDCs in human urine. The widespread detection of BPA and BPS and the measurable occurrence of TCS, TBBPA, TCBPA, and BPF demonstrate exposure to multiple phenolic chemicals in the investigated Bangladeshi population. The analytical strategy provides a robust platform for human biomonitoring and supports future epidemiological studies investigating relationships between environmental phenolic exposure, demographic characteristics, lifestyle practices, and metabolic health.