Transplacental transfer efficiency of environmental chemicals in association with gestational diabetes mellitus

Transplacental transfer efficiency of environmental chemicals in association with gestational diabetes mellitus

Environment International

10.1016/j.envint.2025.109865

https://doi.org/10.1016/j.envint.2025.109865

Jordana Leader, Jessica Robinson, Brian Whitcomb, Damaskini Valvi, Chia-Yang Chen, Yap Seng Chong, Kok Hian Tan, Sharon Ng, James Chun Yip Chan, Johan G. Eriksson, Shiao-Yng Chan, Jonathan Huang, Youssef Oulhote

15 October 2025

Leader, J., Robinson, J., Whitcomb, B., Valvi, D., Chen, C.-Y., Chong, Y. S., Tan, K. H., Ng, S., Chan, J. C. Y., Eriksson, J. G., Chan, S.-Y., Huang, J., & Oulhote, Y. (2025). Transplacental transfer efficiency of environmental chemicals in association with gestational diabetes mellitus. Environment International, 205, 109865. https://doi.org/10.1016/j.envint.2025.109865

Background: Many environmental chemicals have been shown to cross the placental barrier, threatening the health of offspring. Additionally gestational diabetes mellitus (GDM) may affect the transplacental transfer ratios (TTRs) of environmental chemicals, but the rate of transfer of a wide variety of environmental chemicals have not been widely studied. Objective: We examined the TTRs of per- and poly- fluoroalkyl substances (PFAS), phthalates, parabens, bisphenols, and benzophenones in pregnant women, and if GDM increases transplacental transfer of these chemicals. Methods: We examined 576 mother-newborn pairs from the Growing up in Singapore Towards healthy Outcomes (GUSTO) birth cohort enrolled 2009–2010. Fetal cord plasma to maternal plasma ratios from samples around delivery (TTRs) were estimated for 10 PFAS, 6 phthalates, bisphenol-S (BPS), 2 parabens, and 2 benzophenones. GDM was defined as elevated fasting plasma glucose or 2 h plasma glucose from an oral glucose tolerance test at mid-gestation. We estimated covariate-adjusted associations of GDM with TTRs using multivariable regressions. Results: Median TTRs ranged from 0.13 for benzophenone to 2.2 for mono-2-ethylhexyl phthalate. Overall, TTRs were highest for phthalates and short-chain PFAS and lowest for benzophenone and long-chain PFAS. GDM was significantly associated with higher TTRs for perfluorooctanoic, perfluorononanoic, and perfluoroheptanoic acids, BPS, monoethyl phthalate, and oxybenzone. Mothers with GDM had 15% (95% confidence intervals [CI]: 5%, 25%) and 123% (95% CI: 32%, 214%) higher TTRs for oxybenzone and BPS respectively as compared to mothers without GDM. Conclusions: We found high TTRs for multiple short half-life chemicals and more recently introduced short-chain PFAS. Importantly, GDM was associated with increased transplacental efficiency of several classes of environ mental chemicals, particularly chemicals with shorter half-lives.

Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

This study was supported by the National Institute of Health (NIEHS grant number R21ES035148). The GUSTO study is supported by the National Research Foundation under the Open Fund-Large Collaborative Grant (OF-LCG; MOH-000504) administered by the Singapore Ministry of Health’s National Medical Research Council (NMRC) and the Agency for Science, Technology and Research

https://oar.a-star.edu.sg/communities-collections/articles/22765

0160-4120

Singapore Institute of Food and Biotechnology Innovation

https://doi.org/10.1016/j.envint.2025.109865