Association between urinary levels of bisphenol A and its monochlorinated derivative and obesity

Abstract

Population-based studies suggest the association between exposures to bisphenol A (BPA) and obesity. However, no human studies are available that link exposures to chlorinated derivatives of BPA with obesity biomarkers. The objective of this exploratory post hoc analysis of our cross-sectional study's dataset was to evaluate the association between urinary levels of BPA and monochlorinated BPA (mono-ClBPA) with body mass index (BMI) in a random sample of 223 adults (≥18 years) from the general population in Cyprus. Univariate analysis and multiple logistic regressions were performed for descriptive statistics and estimating odds ratio (OR) of above normal BMI, respectively. We observed a relatively weak positive association between urinary mono-ClBPA and BMI, such as (i) 76 ng g⁻¹ in participants with above normal BMI (≥25 kg m⁻²) versus 55 ng g⁻¹ in those with normal BMI (<25 kg m⁻²) (P for mean difference = 0.053) and (ii) higher percentage of participants with above normal BMI in the high urinary mono-ClBPA tertile (63% in tertile 3 and 57% in tertile 2 versus 50% in tertile 1, P for trend = 0.056). Similar tests of association between urinary BPA and BMI showed null outcome. A dichotomously-classified group analysis showed an increased odds ratio (OR) for higher BMI in the group with high creatinine-adjusted urinary levels of BPA and mono-ClBPA when compared with the participants group with low levels for both compounds [logistic model adjusted for gender and health status as potential confounders; adjusted OR (95% CI): 2.34 (1.10, 5.10), P = 0.027]. Measurements of both BPA and its trace chlorinated derivative in human matrices may be warranted for a comprehensive exposure assessment towards improving our understanding of their obesogenic effects.

Keywords:

• Biomarker
• bisphenol A
• body mass index
• exposure
• monochlorinated bisphenol A
• obesity

Acknowledgments

Scientific and technical contribution and discussions by the following co-authors in a relevant earlier publication (Andra et al.^[26]) is much appreciated that laid foundation in preparing this work. Thanks to Dr. Harris Kalyvas, Xanthi D. Andrianou, Dr. Pantelis Charisiadis, and Dr. Costas A. Christophi at the Cyprus International Institute for Environmental and Public Health in association with Harvard School of Public Health, Cyprus University of Technology, Limassol, Cyprus.

Funding

The authors would like to thank the Cyprus Research Promotion Foundation for funding this study (AEIFORIA/ASTI/0311(BIE)/20) with Structural Funds of the European Commission awarded to the corresponding author, Dr. Konstantinos C. Makris.