Accurately assessing a person's exposures to putative environmental toxicants is central to the challenge of studying environmental health effects. The lack of low cost, easy-to-use personal sampling technology hinders epidemiological studies especially in disadvantaged populations. Our passive wristband sampler was developed to provide a relevant, quantifiable assessment. We propose to introduce an improved approach for measuring and characterizing polycyclic aromatic hydrocarbons (PAH) in disadvantaged communities. In phase 1 (R21), in an ongoing epidemiological cohort study of pregnant women in NYC, the performance of 4 exposure assessment methodologies will be evaluated with twenty-five pregnant volunteers recruited from a community health clinic located in northern Manhattan. In collaboration with a 501c3 environmental justice community organization, we have further advanced the passive wristband sampler to be an integrated mobile exposure device to capture uniquely-linked exposure and health information in their industrialized neighborhood in Eugene, Oregon. Upon completion of Phase 1 milestones, we will further assess the integration of personal exposure measurements with epidemiology studies of childhood respiratory symptoms in NYC and adult asthma exacerbation in Eugene to assess the relationships between air pollutants, location, and health outcomes in these disadvantaged communities. Through the R33 phase of this project, we will provide proof of principle demonstration that passive wristband samplers can be used for personalized exposure assessment and linkage to health outcomes. Data and results will be made available to our participants and their communities through novel and appropriate data visualization.

Since 1998, the Columbia Center for Children’s Environmental Health (CCCEH) has followed a New York City birth cohort to study the effects of prenatal and childhood exposures to polycyclic aromatic hydrocarbons (PAH) on neurodevelopmental outcomes through 12 years of age. Because of the heightened susceptibility of the developing fetus and young child, early exposures to PAH may be associated with excess risk for neurodevelopmental damage. Repeated waves of assessment in our cohort have revealed a picture of recurrent developmental abnormalities, including moderate cognitive delay at 3-5 years, and increased symptoms of anxiety/depression and attention problems at ages 6-9 years of age. Underlying these cognitive and behavioral anomalies, we have documented a persistent pattern of neurocognitive dysregulation, suggesting that highly exposed children fail to develop along the normal trajectory of improving self-regulatory control that accompanies maturity. We now propose to follow 350 cohort children through age 15-17 years, to assess the cognitive, emotional, and behavioral repercussions of PAH-associated dysregulation into the adolescent years--a critical developmental period in which conduct disturbances, social problems, substance use, and depressive symptoms frequently emerge for the first time, with serious adult consequences. We posit that prenatal PAH exposure will be associated with 1) neuropsychological deficits in reasoning, attentional, inhibitory and emotional control at 15-17 years ; 2) increased clinical symptoms (mood disturbances, high risk behaviors, and the persistence of ADHD symptoms); and 3) atypical developmental trajectories from early childhood through adolescence. This research is significant first because adolescent developmental disorders are serious and highly prevalent. Second, PAH exposures are widespread, yet their long-term effects are poorly understood due to limited exposure assessment. We address this limitation by using two complementary approaches to PAH exposure assessment: personal air monitoring and biomarkers of individual exposure/dose (PAH-DNA adducts). Third, this work rests on a strong brain-based theory that PAH exposure disrupts the developing organism’s capacity for self-regulatory control — a theory that unifies all 3 research projects in this application. The same children with PAH-associated self-regulatory problems (Project1) also manifest higher rates of obesity (Project 2). Neuroimaging in the same cohort suggests that prenatal PAH exposure leads to reduced white matter volumes and deficient self-regulation, providing preliminary yet compelling evidence that prenatal PAH effects on behavioral dysregulation are mediated by anatomical brain changes (Project 3). This study thus provides a unique opportunity to follow an existing cohort, with repeated measures of neuropsychological abilities from birth through the adolescent years, for the purpose of fully observing and better understanding the developmental impacts of PAH—one of the most widespread and toxic environmental contaminants.

Although children in recent birth cohorts (born 2008 to 2010) have lower obesity rates than earlier cohorts, the high rates of obesity among children and adolescents in the U.S. remain a clinical and public health emergency. Understanding prenatal and early life determinants of upward growth trajectories and resultant obesity is a priority for preventing childhood obesity. The CCCEH published the first human data showing that childhood obesity risk through age 7 was associated with prenatal exposures to airborne polycyclic aromatic hydrocarbons (PAH); an effect that persists in our ongoing follow-up of the cohort to age 12 and is consistent with recent animal and other epidemiologic data. Here we propose to follow-up 350 of the cohort children to age 15-17 years for obesity outcomes using MRI scans to measure abdominal visceral adipose tissue (VAT) mass, the component of total fat mass most directly linked to future health risks. This work will determine whether the effects of prenatal PAH exposures on childhood adiposity continue into adolescence; overweight or obesity that persists from childhood into adolescence is likely to continue into adulthood. We will assess the extent to which PAH exposure related increases in weight reflect gains in VAT, the fat deposit that most directly places individuals at increased risk for cardiovascular disease, Type II diabetes, sleep apnea, acid reflux and obesity related cancers. We have also been measuring neurocognitive outcomes in the cohort children throughout childhood and we find that higher adiposity and poorer emotional self-regulation co-occur in the children. Integrating the three proposed projects we propose to investigate the role of prenatal PAH exposures in the development of a cluster of outcomes that encompass obesity and deficits in self-regulation of thought, emotion, and behavior. At age 15-17 we will also collect data on hedonic eating behaviors, including eating as a coping mechanism, emotional eating, binge eating, and food addiction; patterns of eating that we hypothesize will be associated with deficits in self-regulation. We will collect data on sedentary behaviors which are also hypothesized to be related to deficits in self-regulation. The proposed work will establish whether a cluster of outcomes occurs in adolescence that is characterized by greater adiposity, higher hedonic eating behavior, sedentary pursuits, and poorer neuropsychological function on measures of self-regulation and poorer behavioral and emotional function. Lastly using MRI brain scan data previously collected when the children were 9-12 years old, we will determine whether structural and functional differences can be identified in the children’s brains that mediate links between prenatal PAH exposures and these obesity related and neurodevelopmental outcomes in adolescence. Evidence that PAH exposures are part of the multi-factorial set of determinants of obesity risk will provide new avenues for obesity prevention that can be incorporated into multi-level, systems-based approaches to preventing obesity. The birth cohort analyses proposed here are unique and this is the only study population in which these mechanistic hypotheses can be tested.

The Columbia Center for Children’s Environmental Health (CCCEH) has followed a birth cohort of low-income, African-American and Latino children in New York City into their pre-adolescent years to assess the impact of environmental toxicants on health and development. In a pilot study of MRI measures in 40 of these children at 7-9 years of age, we identified abnormalities in anatomical measures of white matter throughout the entire left cerebral hemisphere that were linearly associated with prenatal exposure to airborne polycyclic aromatic hydrocarbons (PAH). Those white matter abnormalities were in turn linearly associated with measures of cognitive, emotional, behavioral, and adiposity (CEBA) problems at the time of MRI scan. Under separate funding, we have collected brain-based MRI measures and neurobehavioral outcomes in 350 preadolescent children of the CCCEH cohort, between 9 and 12 years of age. The MRI dataset in 9-12 year olds includes state-of-the-art measures of brain structure (anatomical MRI), function (functional MRI),anatomical connectivity and white matter integrity (Diffusion Tensor Imaging, or DTI), and neurometabolite concentrations (MR Spectroscopy, or MRS); we will now evaluate the effects of prenatal and early postnatal exposure to PAH on each of those measures of brain structure, function, and metabolism at age 9-12(preadolescence), and how the PAH-related disturbances in brain measures mediate CEBA outcomes at age15-17 (in adolescence -- outcomes that are being assessed in Projects 1 & 2). In addition, we will acquire new anatomical MRI scans at 15-17 years of age (adolescence) in this same cohort to assess the correlations of early PAH exposure with measures of brain structure in adolescence. The new anatomical MRI scans, together with the anatomical scans already collected in preadolescence at ages 9-12, will allow us to assess whether early exposure to high levels of PAH significantly disrupt the normal changes in brain structure within self-regulatory systems from childhood through adolescence, and whether those children with the most disrupted anatomical changes experience the greatest degree of conduct disturbances, substance use, and depression, persistent ADHD symptoms, and adiposity measures, at 15-17 years of age. This information will help us understand whether the adverse organizational effects of early life PAH exposure continue to derail brain development later in life, or whether any compensatory neuroplastic effects occur during this time of transition that help to mitigate those adverse effects. This knowledge can be translated to education and policy and exploited to aid the future development of therapeutic interventions.

Exposure to pyrethroid insecticides is a growing health concern due to the ban on residential use of organophosphate (OP) insecticides. Pyrethroids have replaced OP for residential pest control. Use is increasing across the U.S. and is particularly high in New York City (NYC). Experimental and preliminary epidemiologic data suggest that prenatal exposure may adversely affect child mental, motor and behavioral development. However, additionally research is urgently needed. The goals of this study are to examine whether biomarkers of prenatal exposure to pyrethroid insecticides are associated with adverse children's cognitive, motor and behavioral development. In doing so, we will also validate a urinary biomarker of prenatal exposure to these compounds for use in epidemiologic research. To accomplish this, we use data from two ongoing longitudinal birth cohorts which together comprise n=325 NYC mothers and children. Pyrethroid metabolites will be measured in urine samples collected and stored from all women during pregnancy. Between child ages 48-58 months, families will be invited to our clinic for development assessments. Cognitive development will be assessed using the Wechsler Preschool and Primary Scale of Intelligence-3rd edition; motor development using the Bruininks-Oseretsky Test of Motor Proficiency, 2nd edition; and executive function using the Behavior Rating Inventory of Executive Function-Preschool Version. A home visit will be made to obtain data on the childrearing environment. Child blood samples will be collected to measure lead in whole blood. Questionnaires will be administered to the mother updating social and demographic information, smoking history, and maternal satisfaction and demoralization (the Psychiatric Epidemiology Research Instrument Demoralization Scale) and to gather data on pesticide use. Maternal intelligence will also be assessed (the Test of Non-Verbal Intelligence, 3rd edition). GIS mapping will be used to model neighborhood level SES and other characteristics which may act as a confounder in the current study. Multiple linear regression analysis will be used to examine associations between the pyrethroid metabolites and outcomes, adjusting for potential confounders and multiple comparisons. Results from this study will have immediate public health importance and will inform future studies examining pyrethroid toxicities. Indoor uses of pyrethroid insecticides have been increasing dramatically. Preliminary data suggest that prenatal pyrethroids exposure can adversely affects child learning and behavior. However, no prior study has evaluated associations between pyrethroid metabolites in maternal prenatal urine and cognitive, motor or behavioral outcomes in children.

Exposure to traffic-related air pollution is associated with asthma exacerbations among children. Symptomatic adolescents tend to develop persistent disease. Using a longitudinal approach, our group at the Columbia Center for Children's Environmental Health (CCCEH) birth cohort has made major scientific advances in the understanding of adverse respiratory health consequences for children following prenatal and postnatal exposure to air pollution. Moreover, we have made important strides in the understanding of epigenetic changes (eg. DNA methylation) that may occur in association with such exposures. Despite increasing research on the associations between short-term exposure to black carbon(BC)/diesel and metal rich particulate matter and changes in DNA methylation, previous studies have lacked accurate assessment of personal exposure and consideration of the effects of early childhood exposure. Nor have they compared changes in DNA methylation that could lead to sustained effects on gene transcription with important clinical outcomes in children. Buccal mucosal cells may be used as a sentinel population representative of cells in the airways and accessed noninvasively. We hypothesize that exposure to BC, nickel (Ni), and vanadium (V) is associated with changes in buccal DNA methylation of proinflammatory asthma genes (interleukin-4, interferon-3, inducible nitric oxide synthases), and that such methylation changes are associated with greater airway inflammation and obstruction among urban adolescents in the CCCEH cohort. The aims are to a) Determine whether recent exposure to BC, Ni, V is associated with altered buccal DNA methylation of several asthma genes among children after controlling for multiple covariates including asthma, and b) Determine whether methylation of asthma genes is associated with greater airway inflammation (fractional exhaled nitric oxide, exhaled breath condensate pH) and airflow obstruction (both assessed twice; 5 days apart) among asthmatic children. 100 asthmatic and 80 nonasthmatic 9 to 13 year old children of African-American and Dominican ethnicity and living in Northern Manhattan and the South Bronx, areas where exposure to traffic- related air pollution has been implicated in asthma and other diseases, will be recruited from the CCCEH cohort. BC levels will be measured by personal monitoring over a 24 hour period repeated 5 days apart and 6 months later. Metals will be measured by residential monitoring over 5 days, repeated 6 months later. Analyses will control for seroatopy, prenatal, previous (age 5-6 years, 9-10 years) and current environmental tobacco smoke (ETS) exposure, and previous (age 5-6, 9-10 years) PAH and BC exposure, BC exposure over the last 6 and 12 months, early residential indoor allergen levels, sex, age, early puberty (via Tanner stage), ethnicity. If the proposed aims are achieved, we will have identified constituent pollutants that may drive clinically-relevant epigenetic events. A greater understanding of the role of ambient BC, nickel and vanadium in inner city asthma exacerbations will stimulate focused intervention to reduce disease among older children.

Experimental evidence indicates that developmental exposure to polybrominated diphenyl ethers (PBDE) disrupts thyroid hormone function and is neurotoxic, leading to deficits in learning and behavior. A small number of epidemiologic studies, each with significant limitations, similarly suggest but do not confirm these associations These relationships have yet to be tested in a human study that can 1) examine the longitudinal impact of PBDE exposure on cognitive and behavioral outcomes throughout the window of brain development (from gestation through adolescence); and 2) determine the impact of PBDE exposure on thyroid hormones as an independent effect or mediator of PBDE-induced neurotoxicity throughout childhood. The central hypothesis to be tested in this application is that both prenatal and postnatal exposure to PBDEs alters circulating thyroid hormones during childhood, thereby influencing cognitive and behavioral developmental indices. We will evaluate this hypothesis within the existing infrastructure of the Columbia Center for Children's Environmental Health's longitudinal birth cohort study. This study has characterized the chemical and social environments of 350 children, residing in inner-city communities of New York City, from birth through age 12 and has conducted detailed assessments of child cognition, behavior, and thyroid hormone status longitudinally throughout childhood. By measuring PBDEs in peripheral blood collected at three developmental time points (birth, ages 2-3, and 5-7 years), we will pursue the following specific aims in children at ages 3-5, 7- 9, and 10-11: 1) determine whether PBDE exposure affects child cognitive development (including learning, working memory and spatial memory); 2) evaluate whether PBDE exposure affects child behavior (including hyperactivity, attention and social problems); and 3) assess whether PBDE exposure affects thyroid function and if thyroid hormone disruption mediates associations between PBDE exposure and child cognitive development and behavior. The proposed research is innovative because it fills several important gaps in the existing epidemiologic literature that have thus far impeded our ability to characterize the longitudinal impact of PBDE exposure occurring throughout childhood on neurodevelopment over time. By evaluating the neurotoxic effects of both pre- and postnatal PBDE exposure in a large, U.S.-based longitudinal cohort study, this study will provide a "fingerprint" of PBDE-induced neurotoxicity in humans, supplying evidence that will implicate or refute the role of thyroid hormone disruption. While the production of all PBDE-containing products is slated to be phased out in the U.S. as of 2013, we anticipate that due to its persistence, PBDE exposure will continue for many years thereafter through residential and dietary reservoirs. Understanding the PBDE fingerprint will allow us to readily distinguish its effects from other potentially neurotoxic environmental exposures. This information will inform the urgent and ongoing policy debate about how best to regulate these and other ubiquitous environmental pollutants.

Second-hand tobacco-smoke (SHS) has a profoundly negative impact on the health of exposed individuals. In adults, where the long-term impacts of SHS exposure are more apparent, SHS is responsible for 50,000 deaths annually. In children, the effects of SHS are likely even more profound. Children exposed to SHS have median nicotine metabolite levels twice those of adults, and SHS exposure is a substantial source of childhood morbidity; resulting in lower respiratory illnesses; cough, phlegm, wheeze, and breathlessness; middle ear disease; and a lower level of lung function. A critical need in the area of research into the health consequences of SHS is the development of effective tools for assessing the early biological response to SHS. These tools could facilitate rapid insights into the causes and consequences of differences in the response to SHS exposure; and, unlike direct measures of SHS exposure levels, could also be used to assess the likely long-term health effects of interventions to minimize SHS exposure in both children and adults. Using genome-wide microarray technologies for assessing mRNA and miRNA expression together with the concept that tobacco smoke creates an airway-wide field of epithelial cell injury, we have developed innovative genomic biomarkers to assess the biologic response to SHS by profiling cells that can be collected from the mouth or nose using minimally invasive procedures. These biomarkers combine the expression levels of multiple genes or miRNAs into composite measures of tobacco-smoke exposure thereby amplifying the tobacco-smoke signal while dampening the otherwise noisy expression levels of individual genes. Preliminary studies show that expression biomarkers measured in buccal or nasal epithelium distinguish young adults with SHS exposure from unexposed individuals. The studies proposed here will validate these biomarkers for assessing the biological response to SHS in 80 SHS-exposed and 80 unexposed children participating in the CCCEH, DISCOVER and ASTHMA-DIET cohorts. Biomarkers of tobacco-smoke exposure derived from microarray-based measurements of nasal or buccal epithelial mRNA or miRNA expression will be compared to measures of SHS exposure derived from questionnaire, air sampling and cotinine. The repeatability of the genomic biomarker measurements will be assessed by repeat sampling of 40 children after 6 months. The proposed research applies innovative tools for measuring the biological response to SHS exposure to multiple established cohorts with carefully characterized exposures, including children at risk for SHS-related disease. The studies bring together a team with expertise in pulmonary medicine, epidemiology, genomics, and biostatistics, a long-term interest in understanding responses to tobacco smoke, and an established record of effective collaboration, to take a critical step in establishing the potential and feasibility of applying these SHS-exposure assessment tools to large-scale epidemiology and gene-environment studies. By measuring the response to exposure, rather than the exposure itself, these studies have the potential to broadly change the paradigm for research into the effects of environmental exposures.

The competitive renewal is responsive to recent epidemiologic and experimental evidence indicating that certain phthalates modulate thyroid function and reduce circulating thyroid hormone levels. The phthalates implicated include those already being studied under the current RO1 (Prenatal Phthalates, Placental Function and Fetal Growth R01 ES013543, Robin Whyatt, PI): di(2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBzP) and dibutyl phthalate (DBP). Exposures to these phthalates are substantial among cohort subjects. Our proposed renewal will determine whether these exposures are associated with perturbations in thyroid function in children followed from birth through age 10-11 years. The study will also determine whether the phthalates are associated with deficits in child neuropsychological function, including in domains that might be associated with phthalate-induced reductions in thyroid function (intelligence, attention, executive function and motor skills). In addition, given that the purported mechanism whereby phthalates affect thyroid levels is through modulation of the Sodium Iodide Symporter (NIS) mediated iodide uptake activity in the thyroid gland, we will also evaluate whether prenatal phthalate exposures modulate expression of the NIS in placental tissue. Such a finding could have important implications for fetal thyroid function, as the NIS is the transport gene responsible for the active transfer of iodide across the placenta. Thyroid hormones during pregnancy and early childhood are critical to brain development, and even modest reductions in hormone levels may have long-lasting effects on child mental, motor and neuropsychological function. However, while prior studies have assessed the relationship between phthalates and thyroid hormones in adults, no prior studies have assessed these relationships in children, or evaluated the effects of prenatal and early-life phthalates exposures on child neuropsychological function. In our preliminary analyses, we found a significant inverse association between maternal prenatal DEHP exposure and child mental development at age 3 years among cohort children. This proposed renewal will build on these preliminary findings to evaluate the role of prenatal and early childhood phthalate exposures on: (1) measures of thyroid function in children from birth through age 11 years; (2) child cognition (language, working memory, executive function, problem solving); (3) child behavior (attention and impulsivity ); (4) child motor development (fine manual control, manual coordination, body coordination, strength and agility, motor speed and visual scanning) and (5) expression of the NIS in placental tissue.

The specific aims are to evaluate whether prenatal and early-life exposures to the endocrine disruptors, bisphenol-A (BPA) and polycyclic aromatic hydrocarbons (PAH), during pregnancy and early-childhood are associated with obesity and metabolic syndrome among children during early adolescence. The research will be conducted within the ongoing longitudinal birth cohort of African American and Dominican children from inner-city communities in New York City being conducted by the Columbia Center for Children's Environmental Health. BPA and PAH exposures are widespread among cohort mothers and children. Both compounds have been linked to obesity and metabolic syndrome in experimental and preliminary human studies. The research is timely; childhood obesity is increasing rapidly within the United States, with rates highest among minority populations. By age 5 years, 43% of our cohort children exceed the 85% of weight for age. The epidemic is likely to have significant public health implications, particularly among minority populations, as obesity is linked to risk of type 2 diabetes and cardiovascular disease. We propose to follow the children in the cohort to age 8-10 years and will assess height, weight, and body composition at ages 5, 7 and 8-10 years and metabolic syndrome components at ages 8-10. Exposure dosimeters are PAH concentrations in maternal prenatal personal air samples and PAH and BPA metabolites concentrations in urine samples collected and stored from the mother during pregnancy and from the child at ages 3,5, and 7 years. We hypothesize that prenatal exposure to PAH and BPA (1) will be associated with higher weight gain trajectories from age 5 to 8-10, and at age 8-10 years with BMI z-score, fat mass and metabolic syndrome components and (2) will alter the methylation status of key genes involved in adipogenesis and hunger control measured in umbilical cord while blood cells, which will mediate the association between postnatal exposures to the endocrine disruptors and childhood obesity outcomes. The research will provide important data on whether prenatal/early-life exposures to endocrine disruptors predicts childhood obesity/metabolic syndrome and will test hypotheses regarding underlying epigenetic mechanisms.

17% of U.S. children have been diagnosed with a learning or behavior disorder. We are proposing policy relevant research on the contribution of prenatal exposures to the common endocrine disruptors, polycyclic aromatic hydrocarbons (PAH) and bisphenol-A (BPA), to neurodevelopmental disorders in early adolescence, and epigenetic mechanisms as mediators of these effects. The project takes advantage of our ongoing cohort study of children residing in low-income, minority neighborhoods of New York City who have been followed by the Columbia Center for Children's Environmental Health (CCCEH) since 1998 and of our new study of younger siblings (Sibling/Hermanos cohort). Our cohorts provide a unique opportunity to evaluate the longer-term consequences of prenatal exposure to PAH and, for the first time, to assess the effect of prenatal BPA exposure through the peri-pubertal years, elucidating the role of epigenetic mechanisms in their neurobehavioral impacts. Aim1: Determine whether prenatal exposures to the endocrine disruptors PAH and BPA are associated with adverse neurobehavioral outcomes in peri-pubertal children, as measured by diagnostic assessment of child psychopathology and cognitive functioning. Aim 2: Determine whether prenatal exposure to PAH or BPA is associated with epigenetic changes in umbilical cord white blood cells (DNA methylation validated by gene expression) in candidate genes/pathways associated with endocrine disruption and immune dysregulation known to be critical in fetal brain development, and whether altered methylation and gene expression is associated with the neurobehavioral outcomes described in Aim 1. Aim 3: Using GIS, determine the extent to which neighborhood-level conditions contribute to neurobehavioral outcomes and/or moderate the individual-level associations between exposure to PAH or BPA and child neurodevelopment (as seen in Aims 1 and 2). Understanding of the multi-factorial etiology and mechanisms of developmental disorders that affect children's academic performance will open new avenues for prevention.

The primary goal of this research is to evaluate the impact of prenatal exposure to polycyclic aromatic hydrocarbons (PAH) on genome-wide epigenetic methylation patterns measured in cord blood samples of sibling-pairs. In utero exposure to PAHs, which are common traffic-related air pollutants, is an established risk factor for adverse birth outcomes, neurodevelopmental deficits, the development of childhood asthma, and markers of precancerous DNA damage. Epigenetic changes, including CpG methylation, are potential mechanisms by which environmental exposures like PAH can alter gene expression, leading to these adverse outcomes. However, it is also clear that some observed differences in methylation measured in umbilical cord blood are the result of factors other than prenatal PAH exposure. During the independent phase of this K99-R00 award, I propose to use the techniques I have learned during the mentored phase to explore the association between prenatal PAH exposure and epigenetic changes by comparing the methylation signature of full and half siblings. Using a paired approach, this design enables a more careful assessment of the impact of PAH exposure on epigenetic markers by controlling unmeasured confounding resulting from partially shared environmental, epigenetic, and genetic characteristics of siblings, which is not possible in a study of unrelated children. The specific aims are to: 1) compare the genome-wide methylation patterns in the cord blood samples of full and half siblings using bioinformatics methods; 2) evaluate the effect of prenatal PAH exposure on the epigenetic methylation signatures of sibling-pairs; 3) explore the association between birth outcomes, including gestational age, birth weight, birth length, and head circumference and PAH-related epigenetic methylation patterns in sibling-pairs; 4) explore whether PAH-related epigenetic methylation signatures mediate the observed relationship between prenatal PAH exposure and adverse birth outcomes in sibling-pairs; and 5) To evaluate the association between PAH-related methylation patterns measured in cord blood and three year developmental outcomes.

The purpose of this study is to assess the effects of pre- and postnatal exposure to the organophosphorus (OP) pesticide chlorpyrifos (CPF) on neurobehavioral functioning in a cohort of inner-city children who have reached 9 years of age. This work builds on, and shares a cohort with, a prospective cohort study of ambient air pollutant effects on child development and respiratory health, being conducted by the Columbia Center for Children's Environmental Health (NIEHS R01 ES08977, P.I. Perera:11/01/03-10/31/08; 5 P01 ES09600/EPA RD-83214101, P.I. Perera, Co-I Rauh:11/01/03-10/31/08). Previous findings from the Children's Center study reveal adverse effects of prenatal exposure to CPF (validated with biomarkers in cord blood) on birth weight (Whyatt et al., 2004), cognitive and motor development, and neuro-behavioral problems at 3 years (Rauh et al., 2006). Affected neurobehavioral areas include attention and ADHD-- conditions with serious long-term clinical implications. Based on these findings, and evidence from the experimental literature showing long-term, possibly irreversible effects of CPF exposure on brain development and sensorimotor activity (Dam et al, 2000; Levin et al, 2002; Slotkin et al, 2005), we now propose to evaluate the longer-term neurodevelopmental effects of CPF in 300 9-year-old children. We will use Magnetic Resonance Imaging (MRI) to define the intermediary neurobiological effects of CPF exposure on the structure, metabolism, and anatomical connectivity of the brain in all 300 children. CPF was selected as a model for translational research because it is representative of the class of OP pesticides, well characterized, and well-studied in animals. Furthermore, agricultural and commercial uses continue, despite the 2001 residential ban by EPA. Specifically, we propose to: (1) assess the 9- year effects of prenatal and early childhood exposures to CPF on neurobehavioral (inattention, hyperactivity and depression) and neuropsychological functioning (attentional capacity, memory, impulse control and sensory motor functioning); and (2) assess the 9-year effects of prenatal and early childhood exposures to CPF on measures of brain structure (using anatomical MRI), brain chemistry/cellular metabolism (using magnetic resonance spectroscopy), and anatomical connectivity (using diffusion tensor imaging) in the same children.

This highly innovative project addresses the role of epigenetic changes in the pathogenesis of childhood asthma. There is growing evidence, some from our own research, that prenatal exposure to polycyclic aromatic hydrocarbons (PAH), common urban pollutants from traffic and other combustion sources, may be a risk factor for asthma in childhood. Following up on a recent pilot study that demonstrated proof of principle, the proposed research will determine whether epigenetic changes related to prenatal PAH exposure are involved in the pathogenic process of childhood asthma. The first study will utilize banked human cord white blood cells, paired placental tissue, and clinical outcome data from children, now aged 9/10 years) who are participants in a prospective cohort study in minority communities in New York City (CCCEH cohort). Analysis of DNA methylation in cord blood DMA and gene expression in placental tissue from these children will be used to identify candidate genes that may be involved in the mechanistic pathway between prenatal PAH exposure and childhood asthma at age 9-10 (i.e., that are differentially methylated and expressed in the high vs. low PAH exposure groups). The set of candidate genes will then be tested as potential biologic markers predictive of childhood asthma in this study sample. Those genes that are found to be predictive will then comprise a "candidate epigenome" to be confirmed in a closely linked animal model. In this complementary animal model, pregnant mice will be exposed to a PAH mixture of similar composition to that measured in air samples from the CCCEH cohort. Blood, placenta and target tissue (lung and spleen) collected from offspring at delivery will be examined for PAH-related changes in gene methylation and gene expression, respectively. A group of offspring prenatally exposed will be followed for 4 weeks to determine asthma-like phenotype. Criteria for selecting the final biomarker(s) will be a) high concordance between gene methylation in white blood cells and gene expression in target tissue and b) significant association with asthma-like phenotype. It is anticipated that this research will provide valuable new data on the role of epigenetic changes in the pathogenesis of childhood asthma. If specific methylation changes induced in utero are found to predict asthma and ultimately validated, we will have identified clinically relevant biomarkers for predicting asthma risk in children.

The major objective of the proposed research is to study the impact of early-life exposures to common urban pollutants on neurobehavioral development and asthma in a sample of children living in three low-income, minority communities of New York City (Central Harlem, Washington Heights and the South Bronx). Using a molecular epidemiologic approach with monitoring, biomarkers, and clinical assessments at serial time points, we will extend our study of African-American and Latina urban mothers and children in order to follow the cohort through child age 11 years to assess the longer-term impact of exposures on child health and developmental outcomes. The exposures of concern include airborne polycyclic aromatic hydrocarbons (PAH) and organophosphate pesticides such as chlorpyrifos (CPF). The first Specific Aim (Neurodevelopmental) builds on our prior findings and proposes to evaluate relationships between early exposures (PAHs and CPF) and longer-term neurodevelopment, in order to assess the persistence of neurotoxic effects into the school years, identify effects that may emerge over time, and delve more deeply into the behavioral domains to better understand the significance of behavior problems observed in the preschool years. The second aim (Asthma) also builds on our previous findings with respect to risk factors for asthma. We will repeat the assessment of immunoglobulin (lg)E at ages 5, 7, and 9 and obtain measures of lung function and airway inflammation, and a physician-diagnosis of asthma between ages 5 and 7 years. We will also assess the association between becoming overweight in the first 5 years of life and the development of IgE, airway inflammation, and asthma in childhood. The research will consider the effect of known determinants of disease and potential confounders, including other toxic exposures and demographic factors. By using a multidisciplinary approach to understand the complex pathogenesis of developmental disorders and asthma that impose such a heavy burden on inner-city children, we anticipate that the proposed research will have important implications for prevention.

The proposed study will determine whether early childhood exposures to phthalates are associated with the development of current asthma and proallergic immunoglobulin (Ig) E production at ages five to seven and whether current exposures to phthalates are associated with augmented airway inflammation and diminished lung function at ages five to seven. The research will confirm or refute recent epidemiologic findings of associations between phthalate exposures and childhood asthma, atopy and reduced lung function. This prior research is limited by incomplete exposure and outcome measures. However, results from a pilot undertaken for the proposed study also support the hypothesis that phthalate exposures are risk factors in the development of asthma. The proposed study will be conducted among a cohort of 400 children who reside in minority communities in New York City. These communities experience some of the highest childhood asthma rates in the world. Phthalate exposures are also widespread. The research will be performed within the ongoing longitudinal birth cohort study being conducted by the Columbia Center for Children's Environmental Health (CCCEH). The CCCEH is evaluating the contribution of prenatal and postnatal exposures in the development of asthma and other health outcomes. Children are followed from pregnancy through age seven years. The proposed research is cost effective in that many of the required exposure and outcome measurements are already being gathered within the CCCEH cohort. These include detailed history of respiratory and allergic symptoms, asthma treatment and emergency room visits; lung function testing at age six; allergen levels in house dust samples collected from pregnancy through age five; and measurement of allergic sensitization (total and specific IgE measured at ages two, three, and five years). The phthalates will be measured in stored urine samples collected from the mother during pregnancy and from children at ages three and five years and in newly collected indoor air and urine samples at ages five to seven. Also at age five to seven years, exhaled nitric oxide will be measured as an indicator of airway inflammation and total and allergen-specific IgE levels will be determined. The case ascertainment of current asthma at ages five to seven will be made by a designated board- certified pediatric pulmonologist at the Morgan Stanley Children's Hospital of New York Presbyterian Hospital. Hypotheses to be tested are: (1) that early childhood exposures to the phthalates, as measured by metabolite levels in urine samples collected during pregnancy and at ages three and five years, predict current asthma at ages five to seven and production of IgE antibodies at age seven; and (2) after correcting for early phthalate exposure, current exposure as measured by levels of the parent compounds in indoor air samples and metabolites in urine samples collected at ages five to seven years, will be associated inversely with lung function and positively with airway inflammation at ages five to seven years.