Analytical and Bioanalytical Chemistry

, Volume 399, Issue 3, pp 1071–1079

In-vitro oxidation of bisphenol A: Is bisphenol A catechol a suitable biomarker for human exposure to bisphenol A?

  • Xiaoyun Ye
  • Xiaoliu Zhou
  • Larry L. Needham
  • Antonia M. Calafat
Original Paper

DOI: 10.1007/s00216-010-4344-x

Cite this article as:
Ye, X., Zhou, X., Needham, L.L. et al. Anal Bioanal Chem (2011) 399: 1071. doi:10.1007/s00216-010-4344-x

Abstract

The extensive use of bisphenol A (BPA) in the manufacture of consumer products results in widespread human exposure to the chemical. In the body, BPA undergoes first-pass metabolism to form BPA glucuronide, considered to be a major BPA byproduct. Concentrations of total (free plus conjugated) urinary species of BPA are used to assess human exposure to BPA. However, because BPA can be present in numerous consumer and household products, potential contamination with parent BPA during collection and handling may pose a challenge when measuring BPA in such biological samples as blood or urine. In this study we investigated the in-vitro phase I metabolism of BPA in rat and human liver microsomes by using on-line solid-phase extraction–high-performance liquid chromatography–tandem mass spectrometry to identify phase I metabolites (e.g., BPA oxidation products) that could be used as potential alternative biomarkers of BPA exposure. We unambiguously identified 5-hydroxy BPA (BPA catechol) as an in-vitro oxidative metabolite of BPA, but human microsomes oxidized only about 10% of BPA to BPA catechol. We evaluated the usefulness of BPA catechol as a potential biomarker of human exposure to BPA by measuring total concentrations of BPA catechol and BPA in 20 urine samples. We detected BPA catechol at much lower concentrations and frequency than those of BPA. Furthermore, we found that free BPA catechol was rather unstable in urine, which highlights the importance of sampling techniques to adequate interpretation of biomonitoring data. Together, these findings suggest that BPA catechol may not be a suitable biomarker of environmental exposure to BPA, but could be used to confirm BPA exposure in special populations or in situations when urine specimens were potentially contaminated with BPA.

Keywords

Bisphenol ABisphenol A catecholIn-vitro metabolismIn-vivo metabolismExposure

Supplementary material

216_2010_4344_MOESM1_ESM.pdf (107 kb)
ESM 1(PDF 106 kb)

Copyright information

© Springer-Verlag (Outside the USA) 2010

Authors and Affiliations

  • Xiaoyun Ye
    • 1
  • Xiaoliu Zhou
    • 1
  • Larry L. Needham
    • 1
  • Antonia M. Calafat
    • 1
  1. 1.Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and PreventionAtlantaUSA