Effect of urinary bisphenolA on androgenic hormones and insulin resistance in preadolescent girls: a pilot study from the Ewha Birth & Growth Cohort

Association between bisphenol A exposure and cardiometabolic outcomes: A longitudinal approach

Increased cardiometabolic risk is associated with abnormalities in blood biomarkers profile and adiposity measurements. Some substances found in the food matrix and the environment, called endocrine-disrupting chemicals, may impair cardiometabolic health in the early and later stages of life. Bisphenol A (BPA) is a food contaminant that migrates from food contact materials and may act as an endocrine disruptor, negatively affecting human health. The present work aims to longitudinally assess the association between BPA exposure and cardiometabolic outcomes, considering data from Portuguese population-based birth cohort Generation XXI. Blood insulin (0.06stdβ; 95 %CI:0.03,0.09) and insulin resistance (0.05stdβ; 95 %CI:0.02,0.08) presented a significant longitudinal association with BPA daily exposure after adjustment for important variables and energy. The same findings were observed for fat mass (0.03stdβ; 95 %CI 0.01,0.06) and waist circumference (0.06stdβ; 95 %CI:0.04,0.08). For z-BMI, a significant cross-sectional (0.03stdβ; 95 %CI:0.01,0.04) and longitudinal (0.02stdβ; 95 %CI:0.00,0.04) association was found. This was the first study assessing the association between BPA exposure and health outcomes from childhood to adolescence. We found an association between BPA exposure and increased blood insulin level, insulin resistance, fat mass percentage, waist circumference and z-BMI. Our results point to the need to reduce exposure to BPA in the early stages of life.

Associations of bisphenol A exposure with metabolic syndrome and its components: A systematic review and meta-analysis

Mounting evidence shows that bisphenol A (BPA) is associated with metabolic risk factors. The aim of this study was to review related epidemiologic studies and conduct a meta-analysis to quantitatively estimate the association between BPA and metabolic syndrome. Four electronic databases were systematically searched to identify suitable articles. A total of 47 published studies were finally included. Two studies involved metabolic syndrome. Of the 17, 17, 14, and 13 studies on the relationship between BPA with abdominal obesity, blood pressure, fasting plasma glucose, and dyslipidemia, 10, 6, 3, and 4 studies were included in the meta-analysis, respectively. The results showed that the risk of abdominal obesity increased with the increase of BPA exposure, especially in the group with higher BPA exposure levels (Quartile 2 vs. Quartile 1, pooled OR = 1.16, 95%CI: 1.01, 1.33; Q3 vs. Q1, pooled OR = 1.31, 95%CI: 1.13, 1.51; Q4 vs. Q1, pooled OR = 1.40, 95%CI: 1.21, 1.61). However, there was no significant correlation between BPA exposure and metabolic syndrome components including hypertension, abnormal fasting plasma glucose, and dyslipidemia. The present study found that BPA exposure is significantly associated with a higher risk of abdominal obesity. However, the relationship between BPA with metabolic syndrome and its other components needs further longitudinal studies to verify.

Research advances in identification procedures of endocrine disrupting chemicals

Endocrine disrupting chemicals (EDCs) are increasingly concerned substance endangering human health and environment. However, there is no unified standard for identifying chemicals as EDCs, which is also controversial internationally. In this review, the procedures for EDC identification in different organizations/countries were described. Importantly, three aspects to be considered in identifying chemical substances as EDCs were summarized, which were mechanistic data, animal experiments, and epidemiological information. The relationships between them were also discussed. To elaborate more clearly on these three aspects of evidence, scientific data on some chemicals including bisphenol A, 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane and perchlorate were collected and evaluated. Altogether, the above three chemicals were assessed for interfering with hormones and elaborated their health hazards from macroscopic to microscopic. This review is helpful for standardizing the identification procedure of EDCs.

Re-evaluation of the risks to public health related to the presence of bisphenol A (BPA) in foodstuffs

In 2015, EFSA established a temporary tolerable daily intake (t-TDI) for BPA of 4 μg/kg body weight (bw) per day. In 2016, the European Commission mandated EFSA to re-evaluate the risks to public health from the presence of BPA in foodstuffs and to establish a tolerable daily intake (TDI). For this re-evaluation, a pre-established protocol was used that had undergone public consultation. The CEP Panel concluded that it is Unlikely to Very Unlikely that BPA presents a genotoxic hazard through a direct mechanism. Taking into consideration the evidence from animal data and support from human observational studies, the immune system was identified as most sensitive to BPA exposure. An effect on Th17 cells in mice was identified as the critical effect; these cells are pivotal in cellular immune mechanisms and involved in the development of inflammatory conditions, including autoimmunity and lung inflammation. A reference point (RP) of 8.2 ng/kg bw per day, expressed as human equivalent dose, was identified for the critical effect. Uncertainty analysis assessed a probability of 57-73% that the lowest estimated Benchmark Dose (BMD) for other health effects was below the RP based on Th17 cells. In view of this, the CEP Panel judged that an additional uncertainty factor (UF) of 2 was needed for establishing the TDI. Applying an overall UF of 50 to the RP, a TDI of 0.2 ng BPA/kg bw per day was established. Comparison of this TDI with the dietary exposure estimates from the 2015 EFSA opinion showed that both the mean and the 95th percentile dietary exposures in all age groups exceeded the TDI by two to three orders of magnitude. Even considering the uncertainty in the exposure assessment, the exceedance being so large, the CEP Panel concluded that there is a health concern from dietary BPA exposure.

The Role of the Bisphenol A in Diabetes and Obesity

Bisphenol A is a compound commonly found in products meant for daily use. It was one of the first compounds to be identified as an endocrine disruptor that was capable of disrupting the endocrine system and producing very similar effects to those of metabolic syndrome. It has recently gained popularity in the scientific arena as a risk factor for obesity and diabetes due to its ability to imitate natural oestrogens and bind to their receptors. The aim was to study the possible relationship between the Bisphenol A endocrine disruptor with diabetes and obesity. The analysis of the articles allows us to conclude that Bisphenol A is an additional risk factor to consider in the development of diabetes and obesity, since it is capable of stimulating the hypertrophy of adipocytes and altering the endocrine system by mimicking the effects of the oestrogen molecule, since epidemiological studies carried out have suggested that the same disruptions seen in experimental studies on animals can be found in humans; however, despite many countries having developed policies to limit exposure to this disruptor in their populations, there is a lack of international agreement. Understanding its relationship with obesity and diabetes will help to raise awareness in the population and adopt public health campaigns to prevent exposure-especially among young people-to these substances.

Cohort profile: the Ewha Birth and Growth Study

With the introduction of life-course epidemiology, researchers realized the importance of identifying risk factors in early life to prevent chronic diseases. This led to the establishment of the Ewha Birth and Growth Study in 2001; the study is a prospective birth cohort designed to provide evidence of early life risk factors for a child's growth and health. Participants were recruited from those who visited Ewha Womans University Mokdong Hospital (a tertiary hospital in southwest Seoul, Korea) for prenatal care at 24-28 weeks of gestation. In total, 891 mothers enrolled in this study between 2001 and 2006 and their offspring (n=940) were followed-up. Regular check-up examinations of offspring were conducted at 3 years, 5 years, and 7 years of age and every year thereafter. To consider age-related health issues, extensive data were collected using questionnaires and measurements. In 2021, the study subjects will reach 19 years of age, and we are planning a check-up examination for early adulthood. About 20 years have passed since the cohort data were collected, and we have published results on childhood health outcomes associated with prenatal and birth characteristics, genetic and epigenetic characteristics related to childhood metabolism, the effects of exposure to endocrine disruptors, and dietary patterns in childhood. Recently, we started reporting on topics related to adolescent health. The findings will facilitate identification of early life risk factors for chronic diseases and the development of interventions for diseases later in life.

Phthalate and Bisphenol Urinary Concentrations, Body Fat Measures, and Cardiovascular Risk Factors in Dutch School-Age Children

OBJECTIVE

The purpose of this study was to investigate the associations of urinary phthalates and bisphenols at age 6 years old with body fat and cardiovascular risk factors at 6 and 10 years and with the change from 6 to 10 years.

METHODS

Among 471 Dutch children, the phthalates and bisphenols urinary concentrations at 6 years and BMI, fat mass index, android fat mass, blood pressure, glucose, insulin, and lipids blood concentrations at 6 and 10 years were measured.

RESULTS

An interquartile range increase in di-n-octyl phthalate (DNOP) metabolites concentrations at 6 years was associated with an increased risk of overweight at 6 and 10 years (odds ratio: 1.44; 95% CI: 1.11-1.87, and 1.43; 95% CI: 1.09-1.86, respectively). Also, higher DNOP metabolites concentrations were associated with higher fat mass index at 6 years, higher systolic blood pressure at 10 years, a decrease in high-density lipoprotein cholesterol, and an increase in triglycerides concentrations from 6 to 10 years (P < 0.05). Higher total bisphenols and bisphenol A concentrations were associated with a decrease in BMI from 6 to 10 years (P < 0.01).

CONCLUSIONS

DNOP metabolites are associated with overweight and an adverse cardiovascular profile in childhood. Total bisphenols and bisphenol A are associated with a decrease in BMI from 6 to 10 years.

Effects of a Plastic-Free Lifestyle on Urinary Bisphenol A Levels in School-Aged Children of Southern Italy: A Pilot Study

Bisphenol A (BPA) is an endocrine disruptor (ED) frequently used in food packaging. BPA is used as a monomer in the manufacture of some food packaging. This study aimed to evaluate the urinary BPA concentration in an Italian pediatric cohort, testing the levels of this ED over a period of 6 months, evaluating the effects of a diet regimen with a reduction of Plastic Food Packaging (PFP). One hundred thirty Italian children were enrolled and divided into two groups "School Canteen" and "No School Canteen." The first group consumed one meal at school using a plastic-free service for 5 days/weeks, while the other group did not modify their normal meal-time habits. The BPA levels were tested in urine samples at three time points: T0, is the time before the application of the plastic-free regimen diet; T3, 3 months later; and T6, 6 months later. A reduction of urine BPA levels was detected in the "School Canteen" group. In particular, the reduction was significant analyzing both the intra (among the three testing times) group and inter (between "School Canteen" and "No School Canteen") group variability. Our results show the effects of a diet regimen with a reduction of PFP, demonstrating a connection between urinary BPA levels and food packaging.

Bisphenol A and its analogues: A comprehensive review to identify and prioritize effect biomarkers for human biomonitoring

Human biomonitoring (HBM) studies have demonstrated widespread and daily exposure to bisphenol A (BPA). Moreover, BPA structural analogues (e.g. BPS, BPF, BPAF), used as BPA replacements, are being increasingly detected in human biological matrices. BPA and some of its analogues are classified as endocrine disruptors suspected of contributing to adverse health outcomes such as altered reproduction and neurodevelopment, obesity, and metabolic disorders among other developmental and chronic impairments. One of the aims of the H2020 European Human Biomonitoring Initiative (HBM4EU) is the implementation of effect biomarkers at large scales in future HBM studies in a systematic and standardized way, in order to complement exposure data with mechanistically-based biomarkers of early adverse effects. This review aimed to identify and prioritize existing biomarkers of effect for BPA, as well as to provide relevant mechanistic and adverse outcome pathway (AOP) information in order to cover knowledge gaps and better interpret effect biomarker data. A comprehensive literature search was performed in PubMed to identify all the epidemiologic studies published in the last 10 years addressing the potential relationship between bisphenols exposure and alterations in biological parameters. A total of 5716 references were screened, out of which, 119 full-text articles were analyzed and tabulated in detail. This work provides first an overview of all epigenetics, gene transcription, oxidative stress, reproductive, glucocorticoid and thyroid hormones, metabolic and allergy/immune biomarkers previously studied. Then, promising effect biomarkers related to altered neurodevelopmental and reproductive outcomes including brain-derived neurotrophic factor (BDNF), kisspeptin (KiSS), and gene expression of nuclear receptors are prioritized, providing mechanistic insights based on in vitro, animal studies and AOP information. Finally, the potential of omics technologies for biomarker discovery and its implications for risk assessment are discussed. To the best of our knowledge, this is the first effort to comprehensively identify bisphenol-related biomarkers of effect for HBM purposes.

The Association between Bisphenol A Exposure and Obesity in Children-A Systematic Review with Meta-Analysis

Bisphenol A (BPA) is an environmental chemical that has adverse effects on health, probably causing childhood obesity. However, this association remains controversial, and it is difficult to find evidence for direct causality between environmental exposure and disease using epidemiological studies. In this study, we sought to elucidate the possible causality between BPA exposure and childhood obesity by conducting two meta-analyses showing bidirectional associations, including exposure effect by obesity and obesity risk by exposure. Articles published up to September 2017 were searched in PubMed, Embase, and Cochrane Library. We evaluated observational studies that included measurements of urinary BPA concentration and BMI or body weight. Of 436 articles, a total of 13 studies were included in the meta-analysis. Two meta-analyses were performed to investigate the association between BPA exposure and childhood obesity. The results showed that the relatively high-exposed group had a significantly higher risk of childhood obesity than the relatively low-exposed group (odds ratio = 1.566, 95% confidence interval [CI]: 1.097 to 2.234, p = 0.014). However, the obese group showed no significant difference in the BPA concentration when compared to the normal group (standardized mean difference = 0.166, 95% CI: −0.121 to 0.453, p = 0.257). This study suggested possible causality between BPA exposure and childhood obesity using data from epidemiological studies and showed that BPA exposure itself increased the risk of obesity in children.

Elevated Metabolites of Steroidogenesis and Amino Acid Metabolism in Preadolescent Female Children With High Urinary Bisphenol A Levels: A High-Resolution Metabolomics Study

Health risks associated with bisphenol A (BPA) exposure are controversially highlighted by numerous studies. High-resolution metabolomics (HRM) can confirm these proposed associations and may provide a mechanistic insight into the connections between BPA exposure and metabolic perturbations. This study was aimed to identify the changes in metabolomics profile due to BPA exposure in urine and serum samples collected from female and male children (n = 18) aged 7-9. Urine was measured for BPA concentration, and the children were subsequently classified into high and low BPA groups. HRM, coupled with Liquid chromatography-mass spectrometry/MS, followed by multivariate statistical analysis using MetaboAnalyst 3.0, were performed on urine to discriminate metabolic profiles between high and low BPA children as well as males and females, followed by further validation of our findings in serum samples obtained from same population. Metabolic pathway analysis showed that biosynthesis of steroid hormones and 7 other pathways-amino acid and nucleotide biosynthesis, phenylalanine metabolism, tryptophan metabolism, tyrosine metabolism, lysine degradation, pyruvate metabolism, and arginine biosynthesis-were affected in high BPA children. Elevated levels of metabolites associated with these pathways in urine and serum were mainly observed in female children, while these changes were negligible in male children. Our results suggest that the steroidogenesis pathway and amino acid metabolism are the main targets of perturbation by BPA in preadolescent girls.

Bisphenol A is associated with insulin resistance and modulates adiponectin and resistin gene expression in obese children

BACKGROUND

Bisphenol A (BPA) exposure has been associated with increased incidence of diabetes and obesity in adults.

OBJECTIVES

To evaluate whether an association between BPA urinary levels and insulin resistance as well as adiponectin and resistin production and serum concentrations may occur in obese children.

METHODS

Clinical and biochemical features of 141 obese children were collected. Serum resistin and adiponectin were evaluated. Insulin resistance and urinary BPA levels were assessed. Moreover, the effect of BPA on adiponectin and resistin gene expression in adipocytes from eight normal weight prepubertal children was investigated by quantitative real-time RT-PCR (qPCR).

RESULTS

Direct association between BPA and homeostasis model assessment (r = 0.23; p: 0.0069) and a strong inverse association between BPA and adiponectin have been found (r = -0.48; p < 0.0001). In adipocytes, resistin expression was detected only after BPA treatment, while adiponectin expression resulted down-regulated after BPA exposure (p < 0.05 at both 10 and 100 nM BPA concentrations).

CONCLUSIONS

We suggest the involvement of BPA in the development of insulin resistance in childhood obesity highlighting that urinary BPA levels are directly associated with insulin resistance regardless of BMI. This association may be explained, at least partly, by the findings that BPA affects resistin and adiponectin production in adipose tissue cultures.

Urinary bisphenol A and pubertal development in Chinese school-aged girls: a cross-sectional study

BACKGROUND

Animal studies suggest that bisphenol A (BPA) may perturb pubertal development in females. However, evidence from human studies is limited.

METHODS

This was a cross-sectional study to investigate the association between BPA exposure and pubertal development in school-aged girls. A total of 655 girls aged 9-18 years were selected from three schools in Shanghai, from May to June 2011. We collected one single spot urine sample from each girl. Urine BPA concentrations were measured by modified high-performance liquid chromatography and categorized according to LOD and the median of those above LOD. Pubertal development status was assessed by using Tanner staging, and age at menarche was collected as a milestone for mid-puberty. Modified Poisson regression was used to estimate adjusted prevalence ratios (PRs) and 95% confidence intervals (CIs).

RESULTS

After adjustment for potential confounders, girls with detected BPA were more likely to have delayed menarche, a mid-puberty event, compared with girls with undetectable BPA; the prevalence ratios (PR) were 0.73 (0.56, 0.95) for those with moderate BPA(LOD-median) and 0.72 (0.52, 0.99) for those with high BPA(>median), respectively. Girls aged 9-12 years with detected BPA were more likely to have reached pubic hair stage 2, the indicator of pubarche; while among girls aged >15 years, those with detected BPA were less likely to have reached pubic hair stage 5, the late stage of pubic hair development.

CONCLUSIONS

BPA exposure was associated with alterations in the timing of pubertal development. Results in the present study should be interpreted with caution because of its cross-sectional nature and the limited sample size in each age group.

Effects of early exposure to phthalates and bisphenols on cardiometabolic outcomes in pregnancy and childhood

Pregnant women are exposed to various chemicals, including endocrine-disrupting chemicals (EDCs) such as phthalates and bisphenols. Increasing evidence suggests that early life exposures to phthalates and bisphenols may contribute to cardiometabolic risks. The aim of this narrative review was to summarize current knowledge of the effects of fetal and childhood exposure to phthalates and bisphenols on child growth and child cardiometabolic outcomes and the effects on maternal outcomes. In total, 54 studies were identified and included. The majority of studies found effects of phthalates and bisphenols on maternal, child growth, and cardiometabolic outcomes. Currently results suggest that early life exposure to phthalates and bisphenols may have a substantial influence on perinatal and postnatal cardiometabolic programming. In a large part of the investigated outcomes studies show contradictory results. However, the majority of the existing evidence is based on non-cohort studies with single samples neglecting time-variant effects and complicating conclusions regarding causal inference. More studies are needed investigating the mechanisms and its potential interactions.

Developmental Exposure to Environmental Chemicals and Metabolic Changes in Children

The incidence of childhood obesity, type 2 diabetes, and other forms of metabolic disease have been rising over the past several decades. Although diet and physical activity play important roles in these trends, other environmental factors also may contribute to this significant public health issue. In this article, we discuss the possibility that widespread exposure to endocrine-disrupting chemicals (EDCs) may contribute to the development of metabolic diseases in children. We summarize the epidemiological evidence on exposure to environmental chemicals during early development and metabolic outcomes in infants and children. Prenatal exposure to EDCs, particularly the persistent organic pollutant DDT and its metabolite DDE, may influence growth patterns during infancy and childhood. The altered growth patterns associated with EDCs vary according to exposure level, sex, exposure timing, pubertal status, and age at which growth is measured. Early exposure to air pollutants also is linked to impaired metabolism in infants and children. As a result of these and other studies, professional health provider societies have called for a reduction in environmental chemical exposures. We summarize the resources available to health care providers to counsel patients on how to reduce chemical exposures. We conclude with a discussion of environmental policies that address chemical exposures and ultimately aim to improve public health.

Adverse Effects of Bisphenol A Exposure on Glucose Metabolism Regulation

Bisphenol A (BPA) is used as basic chemical compound in the production of polycarbonate food containers or epoxy resins coating metallic cans for food and beverages conservation. Its xeno-estrogenic activity alters endocrine-metabolic pathways modulating glucose metabolism and increasing the risk of developing diabetes, insulin resistance, and obesity. Based on in vitro and in vivo experimental research, here we report some of the major BPA adverse effects on tissues that play a key role in the regulation on the whole body’s metabolism. Evidences have shown that BPA is able to exert its endocrine disrupting action altering glucose metabolism and contributing to the onset of metabolic disorders, acting on liver functions and affecting insulin production by the pancreas. Exposure to BPA has been reported also to modulate glucose utilization in muscles, as well as to interfere with adipose tissue endocrine function. In addition, to peripheral tissues, recent studies have shown that BPA by acting in the Central Nervous System affects neuroendocrine regulation of glucose metabolism, promoting glucose metabolism dysfunction such as glucose intolerance and insulin resistance. Thus, exposure to BPA seems to be an important risk factor in the onset of obesity and metabolic syndrome. However, its mechanisms of action need to be further investigated to provide a major evaluation of risk assessment.

Bisphenol A effects on gene expression in adipocytes from children: association with metabolic disorders

Bisphenol A (BPA) is a xenobiotic endocrine-disrupting chemical. In vitro and in vivo studies have indicated that BPA alters endocrine-metabolic pathways in adipose tissue, which increases the risk of metabolic disorders and obesity. BPA can affect adipose tissue and increase fat cell numbers or sizes by regulating the expression of the genes that are directly involved in metabolic homeostasis and obesity. Several studies performed in animal models have accounted for an obesogen role of BPA, but its effects on human adipocytes - especially in children - have been poorly investigated. The aim of this study is to understand the molecular mechanisms by which environmentally relevant doses of BPA can interfere with the canonical endocrine function that regulates metabolism in mature human adipocytes from prepubertal, non-obese children. BPA can act as an estrogen agonist or antagonist depending on the physiological context. To identify the molecular signatures associated with metabolism, transcriptional modifications of mature adipocytes from prepubertal children exposed to estrogen were evaluated by means of microarray analysis. The analysis of deregulated genes associated with metabolic disorders allowed us to identify a small group of genes that are expressed in an opposite manner from that of adipocytes treated with BPA. In particular, we found that BPA increases the expression of pro-inflammatory cytokines and the expression of FABP4 and CD36, two genes involved in lipid metabolism. In addition, BPA decreases the expression of PCSK1, a gene involved in insulin production. These results indicate that exposure to BPA may be an important risk factor for developing metabolic disorders that are involved in childhood metabolism dysregulation.