Urinary Bisphenol A Research Articles

Concentration and Variability of Urinary Phthalate Metabolites, Bisphenol A, Triclosan, and Parabens in Korean Mother–Infant Pairs

Concentrations of toxic chemicals in mothers highly correlate with those in their children; moreover, the levels are higher in children than in mothers. Non-persistent chemicals with a short half-life including phthalate metabolites, bisphenol A (BPA), triclosan (TCS), and parabens are metabolized and excreted through urine. Therefore, we assessed the urine concentrations of phthalate metabolites, BPA, TCS, and parabens; correlated the concentrations with exposure levels; and assessed the within-individual variability of these chemicals in mothers and their infants. We collected 225 and 71 samples from 45 mothers and 36 infants, respectively. For the variability analysis, 189 and 42 samples were collected from nine mothers and their infants, respectively. The median concentrations of phthalate metabolites in the mothers and infants were 0.53–26.2 and 0.81–61.8 μg/L, respectively, and those of BPA, TCS, and parabens were 0.24–76.3 and 2.06–12.5 μg/L, respectively. The concentrations of monoethyl phthalate (MEP), mono-N-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), and BPA in the mothers were positively correlated with those in infants (0.45, 0.62, and 0.89, respectively; p < 0.05), whereas toxic chemical concentrations in infants were higher than those in the mothers. With respect to the within-individual intraclass correlation coefficient (ICC), the first morning void (FMV) of the mothers had high ICCs for all chemicals (range: 0.72–0.99), except for BPA, monobenzyl phthalate (MBzP), and monocarboxyoctyl phthalate (MCOP). The ICC values of most chemicals were moderate to high (range: 0.34–0.99) in the first morning void. However, there were different patterns of ICCs in the infants. These findings indicate the importance of mother–infant pair studies and the necessity of research in infants, as they have different exposure sources and pathways from adults.

Paternal mixtures of urinary concentrations of phthalate metabolites, bisphenol A and parabens in relation to pregnancy outcomes among couples attending a fertility center

BackgroundFew epidemiologic studies have evaluated the impact of paternal environmental exposures, particularly as mixtures, on couples’ pregnancy outcomes. ObjectiveWe investigated whether mixtures of paternal urinary bisphenol A (BPA), paraben, and phthalates were associated with pregnancy outcomes among couples attending a fertility center. MethodsWe included 210 couples undergoing 300 in vitro fertilization (IVF) between 2004 and 2017 in this prospective analysis. We quantified paternal urinary biomarker concentrations in one sample per cycle using isotope-dilution tandem mass spectrometry. We used principal component analysis (PCA) to identify correlations of biomarker concentrations and multivariable Cox proportional hazards models for discrete survival time to estimate the hazard ratios (HRs) and 95% CIs for the associations between PCA-derived factor scores and probability of failing to achieve a live birth. Interactions were also included in the models to examine strength of associations over three vulnerable periods [embryo transfer to implantation, implantation to clinical pregnancy, and clinical pregnancy to live birth]. Models were adjusted for paternal and maternal ages and body mass indexes, urinary dilution (specific gravity) and year of collection, infertility diagnosis, and other PCA factor scores. Sensitivity analyses with further adjustment for maternal PCA factor scores were performed. ResultsWe identified three factors, representing di-2-ethylhexyl phthalate (DEHP) metabolites, BPA and non-DEHP metabolites, and parabens, accounting for 56%, 15% and 10%, respectively, of the total variance explained. An interquartile range (25th and 75th percentiles) increase in the DEHP-related factor score was associated with elevated probability of failing prior to live birth (HR = 1.41, 95% CI: 1.08, 1.81) and the association was stronger between implantation and clinical pregnancy as well as between clinical pregnancy and live birth compared to before implantation. The overall HRs of failure for the BPA/non-DEHP-related and paraben-related factor scores were HR = 1.24 (95% CI: 0.97, 1.59) and HR = 0.99 (95% CI: 0.80, 1.24). We found similar HRs when additionally adjusting for maternal PCA factor scores. ConclusionPaternal mixtures of urinary concentrations of DEHP metabolites were related to higher infertility treatment failure.

Association of urinary bisphenols during pregnancy with maternal, cord blood and childhood thyroid function

BackgroundMost pregnant women are exposed to bisphenols, a group of chemicals that can interfere with various components of the thyroid system. ObjectivesTo investigate the association of maternal urinary bisphenol concentrations during pregnancy with maternal, newborn and early childhood thyroid function. MethodsThis study was embedded in Generation R, a prospective, population-based birth cohort (Rotterdam, the Netherlands). Maternal urine samples were analyzed for eight bisphenols at early (<18), mid (18–25) and late (>25 weeks) pregnancy. Maternal serum thyroid stimulating hormone (TSH), free thyroxine (FT4) and total thyroxine (TT4) were measured in early pregnancy and child TSH and FT4 were measured in cord blood and childhood. ResultsThe final study population comprised 1,267 mothers, 853 newborns and 882 children. Of the eight bisphenols measured, only bisphenol A (BPA) was detected in >50% of samples at all three time-points and bisphenol S (BPS) at the first time-point. There was no association of BPA or the bisphenol molar sum with maternal thyroid function. Higher BPS concentrations were associated with a higher maternal TT4 (β [95% CI] per 1 (natural-log) unit increase: 0.97 [0.03 to 1.91]) but there was no association with TSH or FT4. Furthermore, higher BPS was associated with an attenuation of the association between maternal FT4 and TSH (Pinteraction = 0.001). There was no association of early or mid-pregnancy BPA or early pregnancy BPS with cord blood or childhood TSH and FT4. A higher late pregnancy maternal BPA exposure was associated with a higher TSH in female newborns (Pinteraction = 0.06) and a higher FT4 during childhood in males (Pinteraction = 0.08). DiscussionOur findings show that exposure to bisphenols may interfere with the thyroid system during pregnancy. Furthermore, the potential developmental toxicity of exposure to bisphenols during pregnancy could affect the thyroid system in the offspring in a sex-specific manner.

Effects of bisphenol A on cardiovascular disease: An epidemiological study using National Health and Nutrition Examination Survey 2003–2016 and meta-analysis

As the most widely consumed endocrine-disrupting chemical, bisphenol A (BPA) has been linked to reproductive dysfunction, diabetes mellitus, and obesity. However, the evidence for an association between BPA and cardiovascular disease (CVD) remains insufficient. In the present study, we aimed to identify the association between BPA and CVD, using data from the 2003–2016 National Health and Nutrition Examination Surveys (NHANES). We estimated urine BPA concentration after adjustments for creatinine (ng/mg) and normalized the asymmetrical distribution using natural logarithmic transformation (ln-BPA/Cr). A multivariate logistic regression was performed to evaluate the odds ratio (OR) and 95% confidence interval (CI) for CVD, with ln-BPA/Cr concentration as predictor. We then performed a Mantel–Haenszel meta-analysis with five eligible studies and NHANES 2003–2016 data. Our subjects were 11,857 adults from the NHANES data. After adjusting for age, sex, race/ethnicity, body mass index (BMI), cigarette smoking, diabetes status, hypertension, and dyslipidemia, OR between ln-BPA/Cr and CVD was 1.13 (95% CI: 1.02–1.24). After propensity-score-matching with age, sex, race/ethnicity, BMI, cigarette smoking, diabetes, hypertension, and dyslipidemia, OR continued to be significant for the association between ln-BPA/Cr and CVD (OR: 1.18, 95% CI: 1.04–1.33). A restricted cubic spline plot of this relationship revealed a dose-dependent increase in OR. However, untransformed BPA had a linear relationship with CVD only at low concentrations, whereas the OR of BPA plateaued at high concentrations. In a meta-analysis with 22,878 subjects, after adjusting for age, sex, and various cardiometabolic risk factors, OR was 1.13 (95% CI, 1.03–1.23). In conclusion, our study provides additional epidemiological evidence supporting an association between BPA and CVD.

Quantification of bisphenols in Korean urine using online solid-phase extraction-high-performance liquid chromatography-tandem mass spectrometry

Bisphenol A (BPA), an endocrine-disrupting chemical, has been used as a basic raw material for the production of polycarbonate plastics. As concern over the toxic effects of BPA grows, it is gradually being replaced in many consumer products with compounds such as bisphenol F (BPF) and bisphenol S (BPS). In this study, online solid-phase extraction-high-performance liquid chromatography-tandem mass spectrometry was used to analyze the urinary concentrations of BPA, BPF, and BPS in 2487 Korean urine samples collected between 2017 and 2018. The detection rates and geometric mean (GM) concentrations were as follows: BPA (82.1 %; 0.65 μg/L), BPF (11.1 %; not calculated), and BPS (63.6 %; 0.20 μg/L), respectively. The mean daily intake based on urinary BPA concentrations was 0.013 μg/kg bw/day (95th percentile, 0.089 μg/kg bw/day), which is lower than the tolerable daily intake. This is the first study observing urinary BPA, BPF, and BPS concentrations based on a nationally representative Korean population and could contribute to the evaluation of bisphenol analogue exposure levels in risk assessments.

Fetal exposure to phthalates and bisphenols and childhood general and organ fat. A population-based prospective cohort study.

Fetal exposure to phthalates and bisphenols might have long-lasting effects on growth and fat development. Not much is known about the effects on general and organ fat development in childhood. We assessed the associations of fetal exposure to phthalates and bisphenols with general and organ fat measures in school-aged children. In a population-based, prospective cohort study among 1128 mother-child pairs, we measured maternal urinary phthalate metabolites and bisphenol concentrations in first, second, and third trimester. Offspring body mass index, fat mass index by dual-energy X-ray absorptiometry, and visceral and pericardial fat indices and liver fat fraction were measured by magnetic resonance imaging at 10 years. After adjustment for confounders and correction for multiple testing, an interquartile range increase in first trimester phthalic acid concentrations remained associated with a 0.14 (95% confidence interval: 0.05, 0.22) standard deviation score increase in pericardial fat index. We also observed tendencies for associations of higher maternal low molecular weight phthalate urinary concentrations in second trimester with childhood pericardial fat index, but these were not significant after adjustment for multiple testing. High molecular weight phthalate, di-2-ethylhexyl phthalate, and di-n-octyl phthalate concentrations were not associated with childhood outcomes. Maternal urinary bisphenol concentrations were not associated with childhood adiposity. Maternal first trimester phthalic acid concentrations are associated with increased childhood pericardial fat index at 10 years of age, whereas maternal bisphenol concentrations are not associated with childhood adiposity. We did not find significant sex-specific effects. These findings should be considered as hypothesis generating and need further replication and identification of underlying mechanisms.

Associations of urinary phenolic environmental estrogens exposure with blood glucose levels and gestational diabetes mellitus in Chinese pregnant women

BackgroundEndocrine-disrupting chemicals (EDCs) are considered to be related to diabetes, but studies of the association between phenolic EDCs and gestational diabetes mellitus (GDM) are limited. ObjectivesTo assess associations of maternal urinary bisphenol A (BPA), nonylphenol (NP), and 2-tert-octylphenol (2-t-OP) with GDM occurrence. MethodsA cross-sectional study was performed among 390 Chinese women at 24–28 weeks of gestation. GDM was diagnosed with a 2-h 75-g oral glucose tolerance test (OGTT). BPA, NP, and 2-t-OP concentrations were determined in urine samples. Linear and logistic regression tests evaluated associations of BPA, NP, and 2-t-OP with blood glucose levels and GDM prevalence. ResultsThe 2-t-OP concentrations in GDM patients were significantly higher than in non-GDM women with median values of 2.23 μg/g Cr and 1.79 μg/g Cr, respectively. No significant difference was observed in BPA and NP. Urinary 2-t-OP was positively associated with blood glucose levels after adjustment for several confounding factors and urinary BPA and NP. Higher 2-t-OP levels were associated with higher odds of GDM (OR: 5.78; 95% CI: 2.04, 16.37), whereas higher NP levels were associated with lower odds (OR: 0.22; 95% CI: 0.05, 0.85) in the adjusted models. In addition, compared to the first quartile of 2-t-OP, the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for GDM in the second, third, and fourth quartiles were 2.81 (1.23, 6.42), 3.01 (1.30, 6.93), and 5.49 (2.24, 13.46), respectively. ConclusionOur study indicates that, for the first time to our knowledge, exposure to 2-t-OP is associated with a higher risk of GDM. However, higher NP exposure is associated with lower GDM risk. Further studies are necessary to affirm the associations of 2-t-OP and NP with GDM, and to elucidate the causality of these findings.

Prenatal exposure to bisphenol S and altered newborn mitochondrial DNA copy number in a baby cohort study: Sex-specific associations

Bisphenol S (BPS) is a main substitute for bisphenol A, which are ubiquitous in human daily products. Newborn mitochondrial DNA copy number (mtDNAcn) is considered as a marker for biological aging and human health, and has been related to diseases in later life. We recruited 762 mother-newborn pairs in a birth cohort study between 2013 and 2015 in Wuhan, China. Urinary BPS concentrations were detected using ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). MtDNAcn from cord blood was measured by quantitative real-time polymerase chain reaction (qPCR). We applied multiple informant models based on generalized estimating equations to assess the associations between prenatal BPS exposure and mtDNAcn. The median urine concentrations of BPS were 0.32 μg/L, 0.34 μg/L, and 0.36 μg/L in the first, second, and third trimesters, respectively. In the multiple informant models, we observed significant associations between BPS and mtDNAcn among male newborns. Compared with the lowest quarters, the second, third, and the highest quarter of BPS level were associated with 58.00% (95% CI: 76.58%, −24.66%), 64.65% (95% CI: 79.40%, −39.33%) and 59.07% (95% CI: 75.16%, −32.58%) reductions of mtDNAcn in the first trimester, respectively. No significant associations were found in the second and third trimesters. The associations between BPS and mtDNAcn were not found among female newborns. Findings from this study suggested that BPS exposure was related to decreased mtDNAcn in male newborns. The first trimester was identified as the critical windows for BPS exposure during pregnancy.

Association Between Bisphenol A Exposure and Risk of All-Cause and Cause-Specific Mortality in US Adults

Bisphenol A (BPA) is a major public health concern because of its high-volume industrial production, ubiquitous exposure to humans, and potential toxic effects on multiple organs and systems in humans. However, prospective studies regarding the association of BPA exposure with long-term health outcomes are sparse. To examine the association of BPA exposure with all-cause mortality and cause-specific mortality among adults in the United States. This nationally representative cohort study included 3883 adults aged 20 years or older who participated in the US National Health and Nutrition Examination Survey 2003-2008 and provided urine samples for BPA level measurements. Participants were linked to mortality data from survey date through December 31, 2015. Data analyses were conducted in July 2019. Urinary BPA levels were quantified using online solid-phase extraction coupled to high-performance liquid chromatography-isotope dilution tandem mass spectrometry. Mortality from all causes, cardiovascular disease, and cancer. This cohort study included 3883 adults aged 20 years or older (weighted mean [SE] age, 43.6 [0.3] years; 2032 women [weighted, 51.4%]). During 36 514 person-years of follow-up (median, 9.6 years; maximum, 13.1 years), 344 deaths occurred, including 71 deaths from cardiovascular disease and 75 deaths from cancer. Participants with higher urinary BPA levels were at higher risk for death. After adjustment for age, sex, race/ethnicity, socioeconomic status, dietary and lifestyle factors, body mass index, and urinary creatinine levels, the hazard ratio comparing the highest vs lowest tertile of urinary BPA levels was 1.49 (95% CI, 1.01-2.19) for all-cause mortality, 1.46 (95% CI, 0.67-3.15) for cardiovascular disease mortality, and 0.98 (95% CI, 0.40-2.39) for cancer mortality. In this nationally representative cohort of US adults, higher BPA exposure was significantly associated with an increased risk of all-cause mortality. Further studies are needed to replicate these findings in other populations and determine the underlying mechanisms.

Prenatal exposure to multiple phenolic compounds, fetal reproductive hormones, and the second to fourth digit ratio of children aged 10 years in a prospective birth cohort

Select phenols are known to possess hormone-disrupting properties, but no previous study has addressed the potential effects of prenatal exposure to phenol mixtures on fetal reproductive hormones and children’s second to fourth digit (2D: 4D) ratio, a marker for in utero testosterone (T) exposure. We aimed to explore interrelations of prenatal phenol exposures individually and in mixtures, cord serum reproductive hormones, and 2D: 4D ratio of children aged 10 years. Urinary 11 phenol concentrations were determined from 392 pregnant women participating in a longitudinal birth cohort. We estimated associations of prenatal phenol exposures individually and in mixtures with cord reproductive hormones and children’s 2D:4D ratio using three statistical approaches, including generalized linear models (GLMs), elastic net regression (ENR) models and Bayesian kernel machine regression (BKMR) models. In female newborns, the three models showed that maternal triclosan (TCS) concentrations were significantly negatively associated with cord serum T levels [regression coefficient (β) = -0.076, 95% confidence interval (CI): 0.138, −0.013; p = 0.018]. Additionally, maternal urinary bisphenol A (BPA) levels were related to decreases in 2D:4D ratio of the left hand in girls by GLMs (β = −0.003, 95% CI: 0.007, −0.001; p = 0.024) and ENR models, but not BKMR models. We provided evidence that prenatal TCS exposure predicted lower cord serum T levels, and maternal BPA exposure was related to decreased 2D:4D ratio of the left hand in females.

Urinary Concentrations of Bisphenols in the Australian Population and Their Association with the Per Capita Mass Loads in Wastewater.

Health concerns and related regulation of bisphenol A (BPA) in some countries have led to an increase in the production and use of unregulated and poorly understood BPA analogues, including bisphenol S (BPS), bisphenol F (BPF), bisphenol B (BPB), and bisphenol AF (BPAF). To assess the temporal trends of human exposure to BPA analogues, urine and wastewater samples were collected from South East Queensland, Australia between 2012 and 2017 and analyzed for five bisphenols using validated isotope dilution liquid chromatography tandem mass spectrometry methods. BPA and BPS were the predominant bisphenols detected in both urine and wastewater samples, with median concentrations of 2.5 and 0.64 μg/L in urine and 0.94 and 1.1 μg/L in wastewater, respectively. BPB, BPF, and BPAF had low detection frequencies in both urine and wastewater samples. Concentrations of BPA in both urine and wastewater decreased over the sampling period, whereas concentrations of BPS increased, suggesting that BPS has become a BPA replacement. The contributions of urinary excretion to wastewater were calculated by the ratio of daily per capita urinary excretion to wastewater-based mass loads of bisphenols. Urinary BPA and BPS contributed to less than 1% of the load found in wastewater, indicating that much of the BPA and BPS originates from other sources.

Exposure to bisphenols and asthma morbidity among low-income urban children with asthma

Bisphenol A(BPA) has been linked with pediatric asthma development and allergic airway inflammation in animal models. Whether exposure to BPA or its structural analogs bisphenol S (BPS) and bisphenol F (BPF) is associated with asthma morbidity remains unknown. We examined associations between bisphenols and morbidity due to pediatric asthma. We quantified concentrations of BPA, BPS, and BPF in 660 urine samples from 148 predominantly low-income, African American children (aged 5-17 years) with established asthma. We used biobanked biospecimens and data on symptoms, health care utilization, and pulmonary function and inflammation that were collected every 3 months over the course of a year. We used generalized estimating equations to examine associations between concentrations or detection of urinary bisphenols and morbidity outcomes and assessed heterogeneity of associations by sex. We observed consistent positive associations between BPA exposure and measures of asthma morbidity. For example, we observed increased odds of general symptom days (adjusted odds ratio [aOR]= 1.40 [95% C= 1.02-1.92]), maximal symptom days (aOR= 1.36 [95% CI= 1.00-1.83]), and emergency department visits (aOR= 2.12 [95% CI=1.28-3.51]) per 10-fold increase in BPA concentration. We also observed evidence of sexually dimorphic effects; BPA concentrations were associated with increased odds of symptom days and health care utilization only among boys. Findings regarding BPS and BPF did not consistently point to associations with asthma symptoms or health care utilization. We found evidence to suggest that BPA exposure in a predominantly low-income, minority pediatric cohort is associated with asthma morbidity and that associations may differ by sex. Our findings support additional studies, given the high pediatric asthma burden and widespread exposure to BPA in the United States.

Urinary bisphenol A concentrations and in vitro fertilization outcomes among women from a fertility clinic

Bisphenol A (BPA) is a widespread environmental endocrine disrupting chemical. Although many animals and in vitro studies reported that BPA may affect female fertility through the effect on maturing oocytes and meiotic cell division, but the data from human studies are limited and inconclusive. The study was conducted to examine the association between urinary BPA concentration and in vitro reproductive outcomes (metaphase II (MII) oocyte yield, top quality embryo, fertilization rate, implantation rate and clinical pregnancy) among women from an infertility clinic.The study participants were enrolled in the Infertility Center in Poland. 450 women aged 24-44 (n = 674 IVF cycles) provided urine samples. The urinary concentrations of BPA were evaluated using validated gas chromatography ion-tap mass spectrometry method. Clinical outcomes of IVF treatment were abstracted from patients electronic chart records. To assess the relationship between urinary BPA concentrations early examined reproductive outcomes generalized linear mixed models were used.The detection rate of BPA in urine samples was 98% and the geometric mean 1.59 ± 2.15 ng/ml. A significant decrease was observed between urinary concentration of BPA and implantation (p = 0.04) and decreased MII oocyte count (p = 0.03). There was no association between other examined IVF outcomes: embryo quality, fertilization rate and clinical pregnancy and BPA exposure.Exposure to BPA may have a negative effect during the early stages of human development. The studies among the larger and more diverse population are needed to confirm the results.

Correlation between Urinary Bisphenol A (BPA) Levels and Male Reproductive Functions among Sample of Egyptian Population

BPA as a xenoestrogen negatively influences male reproductive functions as well as sperm quality. This study aimed at evaluating the correlation between urinary BPA concentrations and male fertility by assessing semen parameters as well as hormone profile. It included (150) males divided into two groups; infertile cases (n= 100) and fertile controls (n= 50). Results showed highly significant difference in mean urinary BPA concentrations between both groups being higher among infertile group (P-value &lt; 0.001). Besides that, there was statistically significant correlation between the mean urinary BPA concentrations and deterioration of sperm concentration and motility among cases with P-values (&lt; 0.001). Finally, there was statistically significant correlation between mean urinary BPA and hormone levels FSH, LH, T and E2 levels with P-values 0.002, 0.033, 0.001 and &lt; 0.001 respectively.

Dietary contribution to body burden of bisphenol A and bisphenol S among mother-children pairs

Due to the health concerns over bisphenol A (BPA), bisphenol S (BPS) has been used as an alternative in greater quantity. Diet is considered as the major source of exposure to bisphenols; however, its contribution to the total body burden has not been fully understood. In the present study, a 3-day dietary intervention was carried out for a group of mother and child(ren) pairs (37 families, 93 subjects), and contribution of the dietary factors to body burden of both bisphenols was investigated. During the intervention, the participants were asked to refrain from the foods in cans and plastic containers, fast foods, and delivery foods. Urinary levels of BPA and BPS were measured before, during, and after the intervention. In addition, the questionnaire survey was conducted for potential contributors to BPA and BPS exposure. Following the intervention, urinary levels of BPA and BPS of the mothers decreased on average by 53.1% (95% CI: −30.0, −68.6), and 63.9% (95% CI: −37.1, −79.3), respectively. Among the children, urinary BPA concentrations decreased by 47.5% (95% CI: −25.6, −62.9) by the intervention. However, BPS levels in urine did not change in the children. Interestingly, urinary BPS concentrations of the children measured during the non-intervention period were greater than those of the mothers in the same period. Consumption frequencies of several food items, e.g., canned foods, take-out drinks, or fast foods, were significantly correlated with elevated levels of urinary BPA or BPS concentrations. The results of this intervention study emphasize the importance of dietary contribution to BPA exposure among the mothers and children. Our findings also show that non-dietary sources could be a more important contributor for certain people, especially to BPS exposure among children. Further studies are warranted to identify the sources of BPS exposure among children.

Maternal and childhood urinary phenol concentrations, neonatal thyroid function, and behavioral problems at 10 years of age: The SMBCS study

BackgroundEnvironmental phenols, bisphenol A (BPA), triclosan (TCS), and benzophenone-3 (BP-3), are known as emerging endocrine-disrupting chemicals; however, their impacts on thyroid hormones and children's neurobehaviors are still unclear. ObjectivesWe aimed to examine the associations of prenatal and childhood exposure to phenols with neonatal thyroid function and childhood behavioral problems aged 10 years. MethodsA total of 386 mother-singleton pairs were included from Sheyang Mini Birth Cohort Study (SMBCS), a longitudinal birth cohort in China. We quantified urinary BPA, TCS and BP-3 concentrations in maternal and 10-year-old children's urine samples using gas chromatography tandem mass spectrometry and thyroid function parameters in cord serum samples. Caregivers completed the Strength and Difficulties Questionnaire (SDQ) for their children at 10 years of age. Multivariable linear regression models and logistic regression models were applied to estimate associations of urinary phenol concentrations with thyroid hormones and risks of children's behavioral problems, respectively. ResultsThe median values of urinary BPA, TCS and BP-3 concentrations for pregnant women were 1.75 μg/L, 0.54 μg/L and 0.37 μg/L, while 1.29 μg/L, 6.64 μg/L and 1.39 μg/L for children, respectively. Maternal urinary BPA concentrations were in associations with 1.00% [95% confidence interval (CI): 0.20%, 1.92%] increases in cord serum FT4 concentrations and significantly associated with increased risks of total difficulties [odds ratio (OR): 1.45, 95% CI: 1.07, 1.97], while maternal urinary levels of BP-3 were significantly related to poorer prosocial behaviors (OR: 1.58, 95% CI: 1.04, 2.39) of children at 10 years of age. In sex-stratified analyses, maternal urinary BPA concentrations were related to increased total difficulty subscales only in boys. ConclusionsThe findings indicated that higher prenatal urinary BPA concentrations were associated with increased risks of total difficulties, especially in boys and maternal urinary BP-3 concentrations were related to poorer prosocial behaviors at 10 years.

Bisphenol Exposure and Type 2 Diabetes: New Evidence for a Potential Risk Factor

Bisphenol Exposure and Type 2 Diabetes: New Evidence for a Potential Risk Factor

Exposure to New Emerging Bisphenols Among Young Children in Switzerland.

Restrictions on the use of bisphenol A (BPA) in consumer products led to its replacement by various bisphenol (BP) analogues, yet young children’s exposure to these analogues has been poorly characterized so far. This study aimed to characterize infants’ and toddlers’ exposure to BPA and 14 emerging BP analogues (i.e., bisphenol AF, bisphenol AP, bisphenol B, bisphenol BP, bisphenol C (BPC), bisphenol E, bisphenol F (BPF), bisphenol G, bisphenol M (BPM), bisphenol P, bisphenol PH, bisphenol S (BPS), bisphenol TMC, and bisphenol Z). We extracted infants’ and toddlers’ urine from diapers (n = 109) collected in Swiss daycare centers as a practical and noninvasive alternative approach to urinary biomonitoring. Bisphenols were present in 47% of the samples, with BPC and BPM being the most frequently detected (23% and 25% of all samples, respectively). The mean concentrations of urinary BPS and BPF were greater than that of BPA. This contrasts with data reported previously. Furthermore, statistical analysis revealed a significant and negative correlation between urinary BPM concentration and the population’s age. Our results provide a first characterization of infants’ and toddlers’ exposure to bisphenols in Switzerland. This knowledge can be used to support ongoing biomonitoring studies and to prioritize exposure reduction and prevention strategies.

A Prospective Cohort Study of Bisphenol A Exposure from Dental Treatment

Laboratory studies show that bisphenol A (BPA) leaches from bisphenol A-glycidyl methacrylate (bisGMA)-based dental materials. We aimed to quantify the extent to which children are exposed to BPA from dental treatment with bisGMA materials, by amount of treatment and type of sedation. We hypothesized that posttreatment urinary BPA (uBPA) concentrations would be higher among patients with more surfaces treated with bisGMA-based materials and among patients receiving general anesthesia compared with pretreatment concentrations. We conducted a prospective cohort study in 211 children, 4 to 12 y old, who had no prior resin-based dental treatment. We measured uBPA concentrations twice before treatment and at 2 d and 1, 4, and 16 wk posttreatment. We abstracted treatment data (surfaces treated) from the chart. We generated descriptive statistics and compared pre- and posttreatment uBPA concentrations using generalized estimating equations. Participants were 51% female, 46% non-White, and 74% publicly insured. The median age was 6 y. The mean number of tooth surfaces exposed to BisGMA materials (composites/sealants) was 7.5 (SD 5.3). Overall, uBPA concentrations were 86% higher (95% confidence interval [CI] 42% to 143%, P < 0.001) at 2 d posttreatment compared with pretreatment concentrations. The uBPA concentrations 2 d posttreatment versus pretreatment tended to be higher (112%, 95% CI 53% to 194%) among those receiving treatment on >4 surfaces than those receiving treatment on ≤4 surfaces (50%, 95% CI −2% to 130%). Two days after treatment, uBPA was significantly higher than pretreatment concentrations in children receiving nitrous oxide but not in those receiving general anesthesia. Among all findings, uBPA concentrations returned to baseline by 4 wk. Children experience short-term increases in BPA from dental treatment. The impact of relatively high, short-term BPA exposure on child health is unknown. Given the widespread use of BisGMA-based dental materials and that chronic low-dose BPA exposure may adversely affect child health, strategies that minimize BPA exposure could potentially improve child health.

Urinary bisphenol A, phthalate metabolites, and obesity: do gender and menopausal status matter?

Previous studies of urinary bisphenol A (BPA), phthalate metabolites, and obesity risk have shown inconsistent results. Menopausal status is one of the main factors that affect hormone secretion change in women. In this study, we examined whether urinary BPA and phthalate metabolite levels are associated with obesity and whether the associations differ by sex and menopausal status in a sample of Korean adult populations. We recruited participants at three branches (Yeouido, Gangnam, and Gwanghwamun) of the Korea Medical Institute, a nationwide health check-up center, from 2015 to 2016. Urinary BPA level was measured by high-performance liquid chromatography-tandem mass spectrometry (Agilent 6490 Triple Quad LC-MS/MS; Agilent Technologies, CA, USA). Urinary six phthalate metabolites were analyzed with ultra-high-performance liquid chromatography-tandem mass spectrometry (TSQ Quantum Access Mass; Thermo Fisher Scientific, MA, USA). Participants with body mass index ≥ 25 kg/m2 were defined as general obesity group. Men with waist circumference (WC) ≥ 90 cm and women with WC ≥ 85 cm were defined as abdominal obesity group. Age, sex, alcohol intake, smoking, and exercise were considered in multivariate logistic regression models. Among the total of 702 participants, 211 participants were classified into the general obesity group, and 131 participants were classified into the abdominal obesity group. Urinary phthalate metabolite levels were not associated with general and abdominal obesity in men and women. However, in women, urinary BPA concentration was positively associated with abdominal obesity (OR = 1.50, 95% CI 1.00-2.26). Also, the association was stronger in postmenopausal women (OR = 2.23, 1.01-4.92), while it was weak in premenopausal women (OR = 1.31, 0.78-2.20). In this study, urinary BPA concentration was associated with abdominal obesity in women, especially postmenopausal women. Future studies should consider sex and menopausal status when investigating associations between urinary BPA, phthalate metabolites levels, and obesity.