Pharmacokinetics of bisphenol S in humans after single oral administration

Bisphenol S (BPS) has been introduced as a substitute for bisphenol A (BPA), and widely used in the manufacture of polycarbonate plastics, epoxy resins and thermal papers. Despite its adverse health outcomes and widespread exposure, pharmacokinetic data of BPS are not available for either animals or humans. The objective of the study is to describe pharmacokinetic characteristics of BPS in human body after a single oral administration with a compartmental pharmacokinetic model. Seven healthy young adults were orally exposed to 8.75μg/bw of d₄-BPS, and serum and urine samples were collected for 48h. The concentrations of total and unconjugated d₄-BPS in samples were measured using HPLC-MS/MS. Based on the time-concentration profiles in serum and urine, non-compartmental analysis was performed, and two-compartment model was constructed and validated. As a result of non-compartmental analysis, total d₄-BPS was rapidly absorbed within 1h (0.7±0.3h) after oral administration, and excreted in urine with terminal half-life of <7h (6.8±0.7h). Fractional urinary excretion (F_ue) of total d₄-BPS for 48h was 92±17% (67-104%) for men and 70±36% (59-77%) for women. The two-compartment model well described pharmacokinetic properties of BPS, and its parameter estimates were consistent with those from non-compartmental analysis. This study provides information on absorption, distribution, metabolism and elimination of BPS in human body, and the pharmacokinetic model can be utilized for estimating exposure dose of BPS, contributing to more realistic exposure assessment.