Urinary Concentrations of Bisphenol Mixtures during Pregnancy and Birth Outcomes: The MAKE Study

Gestational Exposure to Endocrine-Disrupting Chemicals of Emerging Concern and the Risk of Developing Gestational Diabetes Mellitus: A Comprehensive Investigation of Sex-Specific and Trimester-Specific Associations

Gestational diabetes mellitus (GDM) is a type of diabetes that arises during pregnancy, leading to long-term adverse consequences for maternal health and fetal development. However, the specific role of endocrine-disrupting chemicals (EDCs) in the pathogenesis of GDM remains controversial. This prospective cohort study sought to investigate how coexposure to bisphenols, parabens, triclosan (TCS), benzophenone-type UV filters, and neonicotinoids (NEOs) affects the odds of GDM. Quantile-based g-computation and Bayesian kernel machine regression showed a significant inverse relationship between EDC mixtures and the reduced risk of GDM (OR = 0.34, 95% CI: 0.13-0.87), which was mainly explained by bisphenol (OR = 0.49, 95% CI: 0.29-0.80) and paraben (OR = 0.60, 95% CI: 0.40-0.91) exposure. Bisphenol S (BPS), bisphenol Z (BPZ), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP) were identified as key contributors to the joint effect. In addition, subgroup analyses suggested that the bisphenols-GDM association was more pronounced in younger/normal-weight participants. The sex-specific impact of exposure to bisphenols on the development of GDM was observed, whereas the second trimester represented a critical window for EDC exposure. Continued research efforts, focusing on causal pathways and nonmonotonic relationships, will be crucial to elucidate the complex influence of EDC exposure on the development of GDM.

Developmental exposure to an environmentally relevant dose of Bisphenol S impairs postnatal growth and disrupts placental transcriptional profile in female rat

Because of its possible adverse effects on human health and its ubiquitous nature, Bisphenol A (BPA) is gradually being replaced by presumably safer alternatives like Bisphenol S (BPS). However, data regarding the effects of developmental exposure to BPS on pregnancy and fetal outcomes are very scarce. Here we show that perinatal exposure to BPS at a very low dose significantly impairs postnatal growth and affects the placental transcriptome in rats. Oral exposure one week before mating and during gestation and lactation to a very low dose of BPS (25 ng/kg/day) is associated with impaired postnatal growth without significant difference in fetal weight on gestational day 18 in females. In contrast, in males, exposure to BPS 25 decreased fetal weight on gestational day 18 but growth restriction did not persist into adulthood. In female, exposure to this very low dose of BPS decreased the placental mRNA expression of fucosyltransferase2 (Fut2), pregnancy-specific glycoprotein 22 (Psg22), Wnt family member 7b (Wnt7b) which are involved in early placental development. Placental DNA methylation of steroid receptor coactivator 2 (src2), a key mediator of steroid induced decidualization, was significantly reduced, while placental src2 mRNA expression was unaffected. These results suggest that early exposure to a very low dose of BPS has long term consequences on growth trajectory and is associated with placental dysregulation.

The Ovary as a Target Organ for New Generation Bisphenols Toxicity

Bisphenols (BPs) are a group of organic compounds used extensively in plastics, coatings, and epoxy resins; they have been of concern recently due to their endocrine-disrupting effects. Among these, bisphenol A (BPA) is the most studied. Regulatory measures, such as the ban on BPA use in baby bottles by the European Union and its restricted use in thermal paper, reflect the growing awareness of the health risks of BPA. To mitigate these risks, analogs such as bisphenol S (BPS), bisphenol F (BPF), and others (BPAF, BPAP, BPB, BPP, BPZ) have been developed as alternatives. Despite their intended safety, these analogs have been detected in environmental media, including indoor dust and thermal receipt paper, as well as in human biological samples. Studies report their presence in urine at levels comparable to BPA, with BPS and BPF found in 78% and 55% of samples, respectively. In addition, BPs have been found in human follicular fluid (FF) at concentrations that could exert some paracrine effects on ovarian function and reproductive health. With the increased global production of BPs, occupational exposure and environmental contamination also increase. This review summarizes what is currently known about the effects of BPs on the ovary and the mechanisms by which PBs exert ovarian toxicity, with a particular focus on oogenesis, folliculogenesis, and steroidogenesis. Further, this review emphasizes their influence on reproductive functions and the need for further biosafety evaluations.

Impact of Endocrine-Disrupting Chemicals, Climate, and Air Pollution on Pregnancy Outcomes: A Scoping Review

Environmental pollutants, including endocrine-disrupting chemicals (EDCs), air pollution, and climate change, are increasingly recognized for their potential impact on pregnancy outcomes. EDCs, found in pesticides, industrial chemicals, and personal care products, are associated with preterm birth and fetal growth restriction, primarily through hormonal interference. Air pollution, notably PM2.5, NO2, and O3, has been linked to increased rates of preterm birth, low birth weight, and stillbirth. Climate factors, such as extreme heat, elevate risks of pregnancy loss and preterm birth, with significant impacts on vulnerable populations across diverse socioeconomic and geographic regions. These exposures contribute to adverse pregnancy outcomes through mechanisms involving oxidative stress, inflammation, and endocrine disruption. The interplay among these environmental factors underscores the need for integrated, longitudinal studies to understand their combined effects on pregnancy outcomes better. Future research should focus on region-specific impacts, cumulative exposure, and policy-driven interventions to mitigate these environmental risks, especially in vulnerable populations disproportionately affected by these hazards. This scoping review synthesizes recent findings from 2019 to 2024 to highlight these associations and identify research gaps.

Effects of combined exposure to two bisphenol plasticizers (BPA and BPB) on Xenopus laevis development

Due to its endocrine disruptive activity, the plastic additive Bisphenol A (BPA) is classified as substance of very high concern (EU ECHA 2017). A correlation between environmental exposure to BPA and congenital defects has been described in humans and in experimental species including the amphibian Xenopus laevis, where severe branchial defects were associated to lethality. The exposure of X. laevis embryos to the BPA analogue bisphenol B (BPB) was recently linked to similar teratogenic effects, with BPB having relative potency about 3 times higher than BPA. The combined BPA-BPB exposure is realistic as both BPA and BPB are detected in human samples and environment. Limited experimental data are available on the combined developmental toxicity of BPA and BPB. The aim of the present work is to evaluate the effects of BPA and BPB mixture in the X. laevis development model, using R-FETAX procedure. The exposure was limited to the first day of development (corresponding to the phylotypic developmental period, common to all vertebrates). Samples were monitored for lethal effects during the full six-day test period and the external morphology was evaluated at the end of the test. Mixture effects were described by modelling, using the PROAST software package. Overall data modelling showed that dose-addiction could not be rejected, suggesting a health concern for co-exposure.

Fetal Origin of Abnormal Glucose Tolerance in Adult Offspring Induced by Maternal Bisphenol A Analogs Exposure

With the widespread use of bisphenol A (BPA) analogs, their health risks have attracted attention. The effects of maternal BPA analogs exposure on glucose homeostasis in adult offspring and the underlying fetal origins require further exploration. Herein, we exposed pregnant mice to two types of BPA analogs─BPB and BPAF; we evaluated glucose homeostasis in adult offspring and maternal-fetal glucose transport by testing intraperitoneal glucose tolerance, determining glucose and glycogen contents, conducting positron emission tomography (PET)/computed tomography (CT), detecting expression of placental nutrient transport factors, and assessing placental barrier status. We observed that adult female offspring maternally exposed to BPB and BPAF exhibited low fasting blood glucose in adulthood, with even abnormal glucose tolerance in the BPAF group. This phenomenon can be traced back to the elevated fetal glucose induced by the increased efficiency of placenta glucose transport in late pregnancy. On the other hand, the expression of genes associated with vascular development and glucose transport was significantly altered in the placenta in the BPAF group, potentially contributing to enhanced fetal glucose. These findings provide preliminary insights into potential mechanisms underlying the disturbance of glucose metabolism in adult female offspring mice induced by maternal exposure to BPA analogs.

The associations between maternal and fetal exposure to endocrine-disrupting chemicals and asymmetric fetal growth restriction: a prospective cohort study

Recent evidence has revealed associations between endocrine-disrupting chemicals (EDCs) and placental insufficiency due to altered placental growth, syncytialization, and trophoblast invasion. However, no epidemiologic study has reported associations between exposure to EDCs and asymmetric fetal growth restriction (FGR) caused by placenta insufficiency. The aim of this study was to evaluate the association between EDC exposure and asymmetric FGR. This was a prospective cohort study including women admitted for delivery to the Maternal Fetal Center at Seoul St. Mary's Hospital between October 2021 and October 2022. Maternal urine and cord blood samples were collected, and the levels of bisphenol-A (BPA), monoethyl phthalates, and perfluorooctanoic acid in each specimen were analyzed. We investigated linear and non-linear associations between the levels of EDCs and fetal growth parameters, including the head circumference (HC)/abdominal circumference (AC) ratio as an asymmetric parameter. The levels of EDCs were compared between fetuses with and without asymmetric FGR. Of the EDCs, only the fetal levels of BPA showed a linear association with the HC/AC ratio after adjusting for confounding variables (β = 0.003, p < 0.05). When comparing the normal growth and asymmetric FGR groups, the asymmetric FGR group showed significantly higher maternal and fetal BPA levels compared to the normal growth group (maternal urine BPA, 3.99 μg/g creatinine vs. 1.71 μg/g creatinine [p < 0.05]; cord blood BPA, 1.96 μg/L vs. -0.86 μg/L [p < 0.05]). In conclusion, fetal exposure levels of BPA show linear associations with asymmetric fetal growth patterns. High maternal and fetal exposure to BPA might be associated with asymmetric FGR.

Invisible Hand behind Female Reproductive Disorders: Bisphenols, Recent Evidence and Future Perspectives

Reproductive disorders are considered a global health problem influenced by physiological, genetic, environmental, and lifestyle factors. The increased exposure to bisphenols, a chemical used in large quantities for the production of polycarbonate plastics, has raised concerns regarding health risks in humans, particularly their endocrine-disrupting effects on female reproductive health. To provide a basis for future research on environmental interference and reproductive health, we reviewed relevant studies on the exposure patterns and levels of bisphenols in environmental matrices and humans (including susceptible populations such as pregnant women and children). In addition, we focused on in vivo, in vitro, and epidemiological studies evaluating the effects of bisphenols on the female reproductive system (the uterus, ovaries, fallopian tubes, and vagina). The results indicate that bisphenols cause structural and functional damage to the female reproductive system by interfering with hormones; activating receptors; inducing oxidative stress, DNA damage, and carcinogenesis; and triggering epigenetic changes, with the damaging effects being intergenerational. Epidemiological studies support the association between bisphenols and diseases such as cancer of the female reproductive system, reproductive dysfunction, and miscarriage, which may negatively affect the establishment and maintenance of pregnancy. Altogether, this review provides a reference for assessing the adverse effects of bisphenols on female reproductive health.

Mixture Effects of Bisphenol A and Its Structural Analogs on Estrogen Receptor Transcriptional Activation

Bisphenol A (BPA) exposure has been widely linked to endocrine-disrupting effects. Recently, many substitutes for BPA have been developed as safe structural analogs. However, they have still been reported to have similar adverse effects. The current study evaluated the effects of bisphenol A and eight structural analogs on the transcription of estrogen receptor alpha (ERα). The effects of binary and ternary mixtures prepared from different combinations of BPA analogs were also evaluated for transcription activity. The measured data of the mixtures were compared to the predicted data obtained by the full logistic model, and the model deviation ratio (MDR) was calculated to determine whether the effects were synergistic, antagonistic, or additive. Overall, the results suggest that the effect of bisphenol compound are additive in binary and ternary mixtures.

Effects of Prenatal Exposure to Bisphenol A Substitutes, Bisphenol S and Bisphenol F, on Offspring's Health: Evidence from Epidemiological and Experimental Studies

Pregnancy and lactation are critical periods for human well-being and are sensitive windows for pollutant exposure. Bisphenol A (BPA) is well demonstrated as a toxicant and has been replaced in the plastic industry with other bisphenol analogs that share similarities in structure and characteristics, most commonly Bisphenol S (BPS) and Bisphenol F (BPF). Maternal exposure to BPS or BPF can result in their accumulation in the fetal compartment, leading to chronic exposure and potentially limiting normal fetal growth and development. This review summarizes considerable findings of epidemiological or experimental studies reporting associations between BPS or BPF and impaired fetal growth and development. Briefly, the available findings indicate that exposure to the two bisphenol analogs during pregnancy and lactation can result in multiple disturbances in the offspring, including fetal growth restrictions, neurological dysfunctions, and metabolic disorders with the potential to persist throughout childhood. The occurrence of premature births may also be attributed to exposure to the two bisphenols. The possible mechanisms of actions by which the two bisphenols can induce such effects can be attributed to a complex of interactions between the physiological mechanisms, including impaired placental functioning and development, dysregulation of gene expression, altered hormonal balance, and disturbances in immune responses as well as induced inflammations and oxidative stress. In conclusion, the available evidence suggests that BPS and BPF have a toxic potential in a compartment level to BPA. Future research is needed to provide more intensive information; long-term studies and epidemiological research, including a wide scale of populations with different settings, are recommended. Public awareness regarding the safety of BPA-free products should also be enhanced, with particular emphasis on educating individuals responsible for the well-being of children.

The Role of Endocrine Disrupting Chemicals in Gestation and Pregnancy Outcomes

Endocrine disrupting chemicals (EDCs) are exogenous substances widely disseminated both in the environment and in daily-life products which can interfere with the regulation and function of the endocrine system. These substances have gradually entered the food chain, being frequently found in human blood and urine samples. This becomes a particularly serious issue when they reach vulnerable populations such as pregnant women, whose hormones are more unstable and vulnerable to EDCs. The proper formation and activity of the placenta, and therefore embryonic development, may get seriously affected by the presence of these chemicals, augmenting the risk of several pregnancy complications, including intrauterine growth restriction, preterm birth, preeclampsia, and gestational diabetes mellitus, among others. Additionally, some of them also exert a detrimental impact on fertility, thus hindering the reproductive process from the beginning. In several cases, EDCs even induce cross-generational effects, inherited by future generations through epigenetic mechanisms. These are the reasons why a proper understanding of the reproductive and gestational alterations derived from these substances is needed, along with efforts to establish regulations and preventive measures in order to avoid exposition (especially during this particular stage of life).