Robert O Wright

BACKGROUND: Arsenic, cadmium, mercury, and lead are associated with cardiovascular disease in epidemiologic research. These associations may be mediated by direct effects of the metals on blood pressure (BP) elevation. Manganese is associated with cardiovascular dysfunction and hypotension in occupational cohorts.

OBJECTIVES: We hypothesized that chronic arsenic, cadmium, mercury, and lead exposures elevate BP and that manganese lowers BP.

METHODS: We conducted a cross-sectional analysis ...

OBJECTIVE: Increasing evidence suggests that 10 microg/dL, the current Centers for Disease Control and Prevention screening guideline for children's blood lead level, should not be interpreted as a level at which adverse effects do not occur. Using data from a prospective study conducted in Mexico City, Mexico, we evaluated the dose-effect relationship between blood lead levels and neurodevelopment at 12 and 24 months of age.

METHODS: The study population consisted of 294 children whose ...

BACKGROUND: Previous studies suggest that blood lead levels are positively associated with attention deficit/hyperactivity disorder (ADHD) and ADHD-symptoms in children. However, the associations between lead exposure and ADHD subtypes are inconsistent and understudied.

OBJECTIVE: The objective of this study was to explore the association of low-level concurrent lead exposure with subtypes of ADHD symptoms in 578 Mexican children 6-13 years of age.

METHODS: We measured concurrent blood ...

BACKGROUND: Limited epidemiologic data exist on prenatal arsenic exposure and fetal growth, particularly in the context of co-exposure to other toxic metals.

OBJECTIVE: We examined whether prenatal arsenic exposure predicts birth outcomes among a rural U.S. population, while adjusting for exposure to lead and manganese.

METHODS: We collected maternal and umbilical cord blood samples at delivery from 622 mother-infant pairs residing near a mining-related Superfund site in Northeast ...

Prenatal smoke exposure, maternal obesity, aberrant fetal growth, and preterm birth are all risk factors for offspring metabolic syndrome. Cord blood aryl-hydrocarbon receptor repressor (AHRR) DNA methylation is responsive to maternal smoking during pregnancy. AHRR serves not only to inhibit aryl-hydrocarbon receptor (AHR) transcription, which is involved in mediating xenobiotic metabolism, but it is also involved in cell growth and differentiation. Other than maternal smoking, other ...

The extent of children's exposure to multiple toxic metals is not well described in many developing countries. We examined metal exposures in young children (6-37 months) from Montevideo, Uruguay and their mothers (15-47 years) participating in a community-based study. Hair samples collected from 180 children and their mothers were analyzed for: lead (Pb), cadmium (Cd), manganese (Mn), and arsenic (As) concentration using inductively coupled plasma-mass spectrometry (ICP-MS). Median ...

BACKGROUND: Brain growth and structural organization occurs in stages beginning prenatally. Toxicants may impact neurodevelopment differently dependent upon exposure timing and fetal sex.

OBJECTIVES: We implemented innovative methodology to identify sensitive windows for the associations between prenatal particulate matter with diameter ≤ 2.5 μm (PM2.5) and children's neurodevelopment.

METHODS: We assessed 267 full-term urban children's prenatal daily PM2.5 exposure using a validated ...

INTRODUCTION: Changes in mitochondrial DNA (mtDNA) can serve as a marker of cumulative oxidative stress (OS) due to the mitochondria's unique genome and relative lack of repair systems. In utero particulate matter ≤2.5μm (PM2.5) exposure can enhance oxidative stress. Our objective was to identify sensitive windows to predict mtDNA damage experienced in the prenatal period due to PM2.5 exposure using mtDNA content measured in cord blood.

MATERIAL AND METHODS: Women affiliated with the ...

The balance of contaminant risk and nutritional benefit from maternal prenatal fish consumption for child cognitive development is not known. Using data from a prospective cohort study of 341 mother-child pairs in Massachusetts enrolled in 1999-2002, the authors studied associations of maternal second-trimester fish intake and erythrocyte mercury levels with children's scores on the Peabody Picture Vocabulary Test (PPVT) and Wide Range Assessment of Visual Motor Abilities (WRAVMA) at age ...

RATIONALE: The influence of particulate air pollution on respiratory health starts in utero. Fetal lung growth and structural development occurs in stages; thus, effects on postnatal respiratory disorders may differ based on timing of exposure.

OBJECTIVES: We implemented an innovative method to identify sensitive windows for effects of prenatal exposure to particulate matter with a diameter less than or equal to 2.5 μm (PM2.5) on children's asthma development in an urban pregnancy ...

BACKGROUND: DNA methylation is an epigenetic mark that regulates gene expression. Changes in DNA methylation within white blood cells may result from cumulative exposure to environmental metals such as lead. Bone lead, a marker of cumulative exposure, may therefore better predict DNA methylation than does blood lead.

OBJECTIVE: In this study we compared associations between lead biomarkers and DNA methylation.

METHODS: We measured global methylation in participants of the Normative Aging ...

BACKGROUND: The impact of prenatal ambient air pollution on child asthma may be modified by maternal stress, child sex, and exposure dose and timing.

OBJECTIVE: We prospectively examined associations between coexposure to prenatal particulate matter with an aerodynamic diameter of less than 2.5 microns (PM2.5) and maternal stress and childhood asthma (n = 736).

METHODS: Daily PM2.5 exposure during pregnancy was estimated using a validated satellite-based spatiotemporally resolved ...

BACKGROUND: Manganese is both an essential element and a known neurotoxicant to children. High manganese exposures have been associated with negative reproductive outcomes in animals, but few epidemiologic studies have examined the effects of human fetal manganese exposure.

METHODS: We studied the association between maternal and umbilical cord blood manganese levels and birth weight in a cohort of 470 mother-infant pairs born at term (>or=37 weeks gestation) in Ottawa County, Oklahoma. ...

BACKGROUND: Evolving animal studies and limited epidemiological data show that prenatal air pollution exposure is associated with childhood obesity. Timing of exposure and child sex may play an important role in these associations. We applied an innovative method to examine sex-specific sensitive prenatal windows of exposure to PM2.5 on anthropometric measures in preschool-aged children.

METHODS: Analyses included 239 children born ≥ 37 weeks gestation in an ethnically-mixed lower-income ...

RATIONALE: Exposure to particulate air pollution has been related to increased hospitalization and death, particularly from cardiovascular disease. Lower blood DNA methylation content is found in processes related to cardiovascular outcomes, such as oxidative stress, aging, and atherosclerosis.

OBJECTIVES: We evaluated whether particulate pollution modifies DNA methylation in heavily methylated sequences with high representation throughout the human genome.

METHODS: We measured DNA ...