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Background: Prenatal phthalates exposures have been related to adiposity in peripuberty in a sex-specific fashion. Untargeted metabolomics analysis to assess circulating metabolites offers the potential to characterize biochemical pathways by which early life exposures influence the development of cardiometabolic risk during childhood and adolescence, prior to becoming evident in clinical markers. Methods: Among mother-child dyads from the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) birth cohort, we measured 9 phthalate metabolites and bisphenol A in maternal spot urine samples obtained during each trimester of pregnancy, corrected for urinary specific gravity and natural log-transformed. In 110 boys and 124 girls aged 8–14 years, we used a mass-spectrometry based untargeted metabolomics platform to measure fasting serum metabolites, yielding 572 annotated metabolites. We estimated the associations between trimester-specific urinary toxicants and each serum metabolite, among all children or stratified by sex and adjusting for child age, BMI z-score, and pubertal onset. We accounted for multiple comparisons using a 10% false discovery rate (q<0.1). Results: Associations between exposures and metabolites were observed among all children and in sex-stratified analyses (q<0.1). First trimester MEP, MiBP, and MCPP were associated with decreased 2-deoxy-D-glucose among all children. Among girls, third trimester concentrations of MECPP, MEHHP, MEHP, and MCPP were associated with 15, 13, 1, and 10 metabolites, respectively, including decreased choline and increased acylcarnitines and saturated FAs (FA). Among boys, third trimester MIBP was positively associated with 9 features including long chain saturated FAs, and second trimester MBzP was inversely associated with thyroxine. Conclusions: Metabolomics biomarkers may reflect sex- and exposure timing-specific responses to prenatal phthalate exposures manifesting in childhood that may not be detected using standard clinical markers of cardiometabolic risk. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the association between BC and urinary concentrations of free-bisphenol A (BPA-F), the biological form of BPA, among women residing in Northern Mexico. Methods: The population under study comprised 394 histologically confirmed BC cases and 404 age-matched controls. Women were interviewed face to face about their sociodemographic and reproductive characteristics. BPA-F was determined by high-pressure liquid chromatography equipped with a fluorescence detector (HPLC/FLD). Logistic regression models were used to estimate the adjusted BC risk in relation to BPA-F. Results: BPA-F geometric mean was significantly higher among cases compared to controls (3.16 μg/L in cases and 2.47 μg/L in controls). A significant adjusted BC odds ratio of 2.31 (95% CI: 1.43–3.74) was estimated for the highest category of BPA-F compared to the lowest category. Conclusion: BPA-F may be an environmental cofactor of BC. Since this is the first report on BPA-F association with BC, our results need to be replicated. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), found in plastics and epoxy resins, is one of the most studied chemicals. BPA is regarded as an endocrine disruptor and has been related to adverse health effects in humans. However, some regulatory agencies around the world have concluded that BPA is safe at current human exposure levels. As the scientific community attempts to settle the debate on BPA's health effects, regulatory agencies have been put into a challenging public health policy situation. The United States has implemented no regulatory actions due to safety concerns, while Europe has used the precautionary principle to guide its regulation in the face of scientific uncertainty. In this paper, we explore the debate surrounding BPA regulation and the possibility for countries to introduce guidelines, using Mexico as an example. Policy change determinants analysis suggest that countries can and should impose regulations on BPA. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied urinary BPA and phthalate metabolite concentrations in Mexican children. [•] Urinary concentrations at third trimester and 8–13years were not correlated. [•] Personal care product use was associated with exposure to several phthalates. [•] Reduced or delayed use of certain personal care products in children may be warranted. [ABSTRACT FROM AUTHOR]

Background: Presence of Bisphenol A (BPA) has been documented worldwide in a variety of human biological samples. There is growing evidence that low level BPA exposure may impact placental tissue development and thyroid function in humans. The aim of this present pilot study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, Mexico and relate these concentrations to risk of delivering prematurely. Methods: A nested case-control subset of 60 participants in the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) study in Mexico City, Mexico were selected based on delivering less than or equal to 37 weeks of gestation and greater than 37 weeks of gestation. Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. Results: BPA was detected in 80.0% (N = 48) of the urine samples; total concentrations ranged from < 0.4 μg/L to 6.7 μg/L; uncorrected geometric mean was 1.52 μg/L. The adjusted odds ratio of delivering less than or equal to 37 weeks in relation to specific gravity adjusted third trimester BPA concentration was 1.91 (95%CI 0.93, 3.91, p-value = 0.08). When cases were further restricted to births occurring prior to the 37th week (n = 12), the odds ratio for specific-gravity adjusted BPA was larger and statistically significant (p < 0.05). Conclusions: This is the first study to document measurable levels of BPA in the urine of a population of Mexican women. This study also provides preliminary evidence, based on a single spot urine sample collected during the third trimester, that pregnant women who delivered less than or equal to 37 weeks of gestation and prematurely (< 37 weeks) had higher urinary concentrations of BPA compared to women delivering after 37 weeks. [ABSTRACT FROM AUTHOR]

This article briefly notes medical news items from around the world. The public health implications of flooding in the Indian state of Bihar are addressed. U.S. National Toxicology Program reports on the health effects of Bisphenol A are noted. The Mexican Supreme Court's approval of abortion rights in Mexico City is also described.