Gestational exposure to phthalates and gender-related play behaviors in 8-year-old children: an observational study.

Background: Phthalates, used in a variety of consumer products, are a group of chemicals that are ubiquitous in the environment, and their metabolites are detectable in most humans. Some phthalates have anti-androgenic properties; a prior study reported an association between gestational exposure to phthalates and reduced masculine behaviors in preschool boys.

Methods: Concentrations of 9 phthalate metabolites were measured in urine collected at 16 and 26 weeks' gestation from pregnant women enrolled in the HOME Study, a prospective pregnancy and birth cohort.

Prenatal PBDE and PCB Exposures and Reading, Cognition, and Externalizing Behavior in Children.

Background: Prenatal polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) exposures may influence children's neurodevelopment.

Objective: We examined the association of prenatal PBDE and PCB exposures with children's reading skills at ages 5 and 8 years, Full-Scale Intelligence Quotient (FSIQ), and externalizing behavior problems at age 8 years.

Methods: From 239 mother-child pairs recruited (2003-2006) in Cincinnati, Ohio, we measured maternal serum PBDE and PCB concentrations, assessed child's reading skills using the Woodcock-Johnson Tests of Achievement III (WJ-III) at age 5 years and the Wide Range Achievement Test-4 (WRAT-4) at age 8 years, tested FSIQ using the Wechsler Intelligence Scale for Children-IV (WISC-IV), and externalizing behavior problems using the Behavioral Assessment System for Children-2 (BASC-2) at age 8 years.

Prenatal Polybrominated Diphenyl Ether Exposure and Body Mass Index in Children Up To 8 Years of Age.

Background: Prenatal exposure to endocrine disruptors has been associated with increased risk of childhood obesity. However, epidemiologic studies on polybrominated diphenyl ethers (PBDEs) are limited despite animal studies indicating PBDEs' potential role as an obesogen.

Objectives: We investigated whether maternal concentrations of BDEs 28, 47, 99, 100, 153, and ΣPBDEs during pregnancy were associated with anthropometric measures in children aged 1-8 years.

Association of Bisphenol A exposure and Attention-Deficit/Hyperactivity Disorder in a national sample of U.S. children.

Background: Bisphenol A (BPA) has been linked to changes in the dopamine system and development of an Attention-Deficit/Hyperactivity Disorder (ADHD) phenotype in animal models, with differing effects in males compared to females. We examined the association between urinary BPA concentrations and ADHD in a national sample of U.S.

Prenatal phthalate exposure and infant size at birth and gestational duration.

Background: Phthalate exposure is widespread. Prior research suggests that prenatal phthalate exposure may influence birth size and gestational duration, but published results have been inconsistent.

Objective: We quantified the relationship between maternal urinary phthalate concentrations and infant birth weight z-scores, length, head circumference, and gestational duration.

Maternal serum perfluoroalkyl substances during pregnancy and duration of breastfeeding.

Background: Perfluoroalkyl substances (PFAS) may affect breast development and decrease duration of breastfeeding, thus interfering with the health benefits of breastfeeding. We investigated the association between maternal PFAS exposure and breastfeeding duration.

Methods: We measured PFAS concentrations in maternal serum collected during pregnancy in 2003-2006.

Patterns, Variability, and Predictors of Urinary Bisphenol A Concentrations during Childhood.

We examined the patterns, variability, and predictors of urinary bisphenol A (BPA) concentrations in 337 children from the Cincinnati, Ohio HOME Study. From 2003 to 2014, we collected two urine samples from women at 16 and 26 weeks of pregnancy and six urine samples from children at 1-5 and 8 years of age. We used linear mixed models to calculate intraclass correlation coefficients (ICCs) as a measure of within-person BPA variability and to identify sociodemographic and environmental predictors.

Prenatal polybrominated diphenyl ether and perfluoroalkyl substance exposures and executive function in school-age children.

Executive function is a critical behavioral trait rarely studied in relation to potential neurotoxicants. Prenatal exposure to polybrominated diphenyl ethers (PBDEs) and perfluoroalkyl substances (PFASs) has been associated with adverse neurodevelopment, but there is limited research on executive function. Data from 256 mother-child pairs in the Health Outcomes and Measures of the Environment Study, a prospective birth cohort (2003-2006, Cincinnati, OH), was used to examine maternal serum PBDEs and PFASs and executive function in children ages 5 and 8 years.

Prenatal Phthalate Exposures and Body Mass Index Among 4- to 7-Year-old Children: A Pooled Analysis.

Background: Phthalates are hypothesized to cause obesity, but few studies have assessed whether prenatal phthalate exposures are related to childhood body mass index (BMI).

Methods: We included 707 children from three prospective cohort studies enrolled in the US between 1998 and 2006 who had maternal urinary phthalate metabolite concentrations measured during pregnancy, and measures of weight and height at ages 4 to 7 years. We calculated age- and sex-standardized BMI z scores and classified children with BMI percentiles ≥85 as overweight/obese.

What Can Epidemiological Studies Tell Us about the Impact of Chemical Mixtures on Human Health?

Humans are exposed to a large number of environmental chemicals: Some of these may be toxic, and many others have unknown or poorly characterized health effects. There is intense interest in determining the impact of exposure to environmental chemical mixtures on human health. As the study of mixtures continues to evolve in the field of environmental epidemiology, it is imperative that we understand the methodologic challenges of this research and the types of questions we can address using epidemiological data.

Prenatal perfluoroalkyl substance exposure and child adiposity at 8 years of age: The HOME study.

Objective: To examine relationships between prenatal perfluoroalkyl substance (PFAS) exposure and adiposity in children born to women who lived downstream from a fluoropolymer manufacturing plant.

Methods: Data are from a prospective cohort in Cincinnati, Ohio (HOME Study). Perfluorooctanoic (PFOA), perfluorooctane sulfonic (PFOS), perfluorononanoic (PFNA), and perfluorohexane sulfonic (PFHxS) acids were measured in prenatal serum samples.

The association between maternal urinary phthalate concentrations and blood pressure in pregnancy: The HOME Study.

Background: Exposure to phthalates, a class of endocrine disrupting chemicals, is ubiquitous. We examined the association of urinary phthalate metabolite concentrations during pregnancy with maternal blood pressure and risk of pregnancy-induced hypertensive diseases.

Methods: We used data from the Health Outcomes and Measures of the Environment Study, a prospective birth cohort of low-risk pregnant women recruited between March 2003 and January 2006.

Association of pyrethroid pesticide exposure with attention-deficit/hyperactivity disorder in a nationally representative sample of U.S. children.

Background: Pyrethroid pesticides cause abnormalities in the dopamine system and produce an ADHD phenotype in animal models, with effects accentuated in males versus females. However, data regarding behavioral effects of pyrethroid exposure in children is limited. We examined the association between pyrethroid pesticide exposure and ADHD in a nationally representative sample of US children, and tested whether this association differs by sex.

Maternal Polybrominated Diphenyl Ether (PBDE) Exposure and Thyroid Hormones in Maternal and Cord Sera: The HOME Study, Cincinnati, USA.

Background: Polybrominated diphenyl ethers (PBDEs) reduce blood concentrations of thyroid hormones in laboratory animals, but it is unclear whether PBDEs disrupt thyroid hormones in pregnant women or newborn infants.

Objectives: We investigated the relationship between maternal PBDE levels and thyroid hormone concentrations in maternal and cord sera.

Methods: We used data from the Health Outcomes and Measures of the Environment (HOME)Study, a prospective birth cohort of 389 pregnant women in Cincinnati, Ohio, who were enrolled from 2003 through 2006 and delivered singleton infants.

Gestational urinary bisphenol A and maternal and newborn thyroid hormone concentrations: the HOME Study.

Bisphenol A (BPA), an endocrine disruptor used in consumer products, may perturb thyroid function. Prenatal BPA exposure may have sex-specific effects on thyroid hormones (THs). Our objectives were to investigate whether maternal urinary BPA concentrations during pregnancy were associated with THs in maternal or cord serum, and whether these associations differed by newborn sex or maternal iodine status.

The associations of triclosan and paraben exposure with allergen sensitization and wheeze in children.

Triclosan and parabens are chemicals used in personal care and medical products as microbicides and preservatives. Triclosan and paraben exposure may be associated with allergy (atopy), but these associations have not been evaluated with respect to other atopic states such as eczema (atopic dermatitis). This study examines the associations of urinary triclosan and paraben concentrations with allergic sensitization and asthma in children according to eczema history.

Challenges and future directions to evaluating the association between prenatal exposure to endocrine disrupting chemicals and childhood obesity.

Obesity is an increasing public health threat worldwide. However, there has been insufficient research addressing the obesogenic potential of prenatal exposure to environmental endocrine disrupting chemicals, largely due to complexities in the design, analysis, and interpretation of such studies. This review describes relevant biological mechanisms, addresses current challenges for investigators, presents potential strategies for overcoming them, and identifies areas where further development is required to improve future research.

Early-life bisphenol a exposure and child body mass index: a prospective cohort study.

Background: Early-life exposure to bisphenol A (BPA) may increase childhood obesity risk, but few prospective epidemiological studies have investigated this relationship.

Objective: We sought to determine whether early-life exposure to BPA was associated with increased body mass index (BMI) at 2-5 years of age in 297 mother-child pairs from Cincinnati, Ohio (HOME Study).

Methods: Urinary BPA concentrations were measured in samples collected from pregnant women during the second and third trimesters and their children at 1 and 2 years of age.

Variability and predictors of urinary concentrations of phthalate metabolites during early childhood.

The variability and predictors of urinary concentrations of phthalate metabolites in preschool-aged children have not been thoroughly examined. Additionally, the impact of temporal changes in the use and restriction of phthalates in children's products has not been assessed. Our objective was to identify demographic, behavioral, and temporal predictors of urinary phthalate metabolite concentrations in young children.

Relationships between lead biomarkers and diurnal salivary cortisol indices in pregnant women from Mexico City: a cross-sectional study.

Background: Lead (Pb) exposure during pregnancy may increase the risk of adverse maternal, infant, or childhood health outcomes by interfering with hypothalamic-pituitary-adrenal-axis function. We examined relationships between maternal blood or bone Pb concentrations and features of diurnal cortisol profiles in 936 pregnant women from Mexico City.

Methods: From 2007-11 we recruited women from hospitals/clinics affiliated with the Mexican Social Security System.

Serum cotinine and whole blood folate concentrations in pregnancy.

Purpose: Prenatal tobacco smoke exposure may be associated with low maternal folate levels that increase the risk of adverse infant and child health outcomes by reducing folate availability during fetal development.

Methods: Using data from the Health Outcomes and Measures of the Environment Study, we examined the relationship between secondhand or active tobacco smoke exposure and whole blood folate concentrations in pregnant women from Cincinnati, Ohio (n = 362) at approximately 16-week gestation. We used multivariable linear regression to examine the association between continuous or categorical serum cotinine levels and whole blood folate levels, adjusting for sociodemographic, dietary, and perinatal variables.

Brief report: are autistic-behaviors in children related to prenatal vitamin use and maternal whole blood folate concentrations?

Prenatal multivitamin/folic acid supplement use may reduce the risk of autism spectrum disorders. We investigated whether 2nd trimester prenatal vitamin use and maternal whole blood folate (WBF) concentrations were associated with Social Responsiveness Scale (SRS) scores at 4-5 years of age in a prospective cohort of 209 mother-child pairs. After confounder adjustment, children born to women taking prenatal vitamins weekly/daily (n = 179) had lower odds of clinically elevated SRS scores (odds ratio 0.

Gestational exposure to endocrine-disrupting chemicals and reciprocal social, repetitive, and stereotypic behaviors in 4- and 5-year-old children: the HOME study.

Background: Endocrine-disrupting chemicals (EDCs) may be involved in the etiology of autism spectrum disorders, but identifying relevant chemicals within mixtures of EDCs is difficult.

Objective: Our goal was to identify gestational EDC exposures associated with autistic behaviors.

Methods: We measured the concentrations of 8 phthalate metabolites, bisphenol A, 25 polychlorinated biphenyls (PCBs), 6 organochlorine pesticides, 8 brominated flame retardants, and 4 perfluoroalkyl substances in blood or urine samples from 175 pregnant women in the HOME (Health Outcomes and Measures of the Environment) Study (Cincinnati, OH).

Phthalate exposure and children's health.

Purpose Of Review: Phthalates are multifunctional chemicals used in personal care products, medications, and plastics. We reviewed the epidemiological literature examining the relationship between early life phthalate exposure and pediatric health outcomes.

Recent Findings: Five studies from Asia, Europe, and the United States suggest that childhood exposure to di-2-ethylhexyl phthalate (DEHP) and butylbenzyl phthalate (BBzP) may increase the risk of allergic diseases including asthma and eczema.