PUBLICATIONS & PRESENTATIONS

Publications

Yi L, *Xu Y, Eckel S, O’Connor S, Cabison J, Rosales M, Chu D, Chavez T, Johnson M, Mason T, Bastain T, Breton C, Dunton G, Wilson JP, Habre R. Time-activity and daily mobility patterns during pregnancy and early postpartum –evidence from the MADRES cohort. Spatial and Spatiotemporal Epidemiology. 2022 

Introduction

Pregnant women’s daily time-activity and mobility patterns determine their environmental exposures and subsequently related health effects. Most studies ignore these and assess pregnancy exposures using static residential measures.

Methods

We conducted 4-day continuous geo-location monitoring in 62 pregnant Hispanic women, during pregnancy and early post-partum then derived trips by mode and stays, classified by context (indoor/outdoor, type). Generalized mixed-effect models were used to examine whether these patterns changed over time.

Results

Women spent on average 17.3 h/day at home. Commercial and service locations were the most popular non-home destinations, while parks and open spaces were seldom visited. Women made 3.5 daily trips (63.7 min/day and approximately 25% were pedestrian-based). Women were less likely to visit commercial and services locations and make vehicle-based trips postpartum compared to the 3rd trimester.

Conclusion

Our findings suggest time-activity patterns vary across pregnancy and postpartum, thus assessing exposures at stationary locations might introduce measurement error.

Hernandez-Castro I., Eckel S.P., Chavez T., Johnson, M., Lerner, D., Grubbs, B., Toledo-Corral, C.M., Farzan, S.F., Habre, R., Dunton, G.F., Breton, C.V., Bastain, T.M. (2021). Household pesticide exposures and infant gross motor development in the MADRES cohort. Paediatric and Perinatal Epidemiology, 1–10.

Background: The development of motor skills in infancy is a vital neurodevelopmental milestone. Although previous studies have explored the neurotoxic effects of agricultural pesticides on infants’ motor development, limited research has examined early postnatal household pesticide use on infants’ motor development, particularly among urban communities.

Objective: This study examined the association between early postnatal household pesticide use and infants’ gross and fine motor development at 6 months of age.

Methods: Questionnaires were administered via telephone to 296 mother-infant dyads in the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) pregnancy cohort. Early life household pesticide use was assessed via questionnaire administered when infants turned 3 months old and gross and fine motor development was assessed by the Ages and Stages Questionnaire (ASQ-3) at 6 months old. Infant gross motor scores were reverse coded so that higher scores indicated lower gross motor performance. Negative binomial regressions were performed to assess the relationship between household pesticide use and infant gross motor development.

Results: Infants were predominantly Hispanic (78.7%) and full term (gestational age at birth: 39.0 ± 1.9 weeks), with 22.3% of maternal participants reporting household use of rodent and insect pesticides. Adjusting for recruitment site, maternal age, ethnicity, household income, education, infant corrected age, infant sex, and home type, infants with maternal-reported household use of rodent and insect pesticides had 1.30 times higher expected gross motor scores (95% confiidence interval 1.05, 1.61) than infants with no reported use of household pesticides, with higher scores indicating reduced gross motor performance.

Conclusions: Our results suggest household use of rodent and insect pesticides may harm infants’ gross motor development in early childhood. Future research should evaluate the impact of specific household chemicals in infant biospecimens and their associations with infant motor development to confirm these findings.

Niu, Z.; Naya, C.H.; Reynaga, L.; Toledo-Corral, C.M.; Johnson, M.; Yang, T.; Grubbs, B.; Lurvey, N.; Lerner, D.; Dunton, G.F.; et al. Association of Breastfeeding Duration with 12-Month Postpartum Blood Lipids in a Predominately Lower-Income Hispanic Pregnancy Cohort in Los Angeles. Int. J. Environ. Res. Public Health 2022, 19, 3008.

Breast feeding may protect women’s long-term cardiovascular health; however, breast feeding related postpartum lipid changes remain unclear. We aim to examine associations of breastfeeding duration with maternal lipids at 12 months postpartum. In a subsample (n = 79) of the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) cohort, breastfeeding status and duration at 3, 6, and 12 months postpartum were self-reported. Serum levels of lipids, including total cholesterol, triglycerides (TG), high-, low-, and very low-density lipoprotein cholesterol (HDL-C, LDL-C, VLDL-C), were measured from blood samples collected at 12 months postpartum. We used linear regression models to compare lipids by breastfeeding duration, adjusting for potential confounders. Women who were breastfeeding at 12 months had higher HDL-C (mean: 41.74 mg/dL, 95% CI: 37.27–46.74 vs. 35.11 mg/dL, 95% CI: 31.42–39.24), lower TG (80.45 mg/dL, 95% CI: 66.20–97.77 vs. 119.11 mg/dL, 95% CI: 98.36–144.25), and lower VLDL-C (16.31 mg/dL, 95% CI: 13.23, 20.12 vs. 23.09 mg/dL, 95% CI: 18.61–28.65) compared to women who breastfed for <6 months. No lipids were significantly different between women who breastfed for 6–11 months and for <6 months. Each month’s increase in breastfeeding duration was significantly, inversely associated with TG and VLDL-C and positively with HDL-C. Adjusting for fasting status, demographics, pre-pregnancy body mass index, breastfeeding frequency, and pregnancy complications did not appreciably change effect estimates. Breastfeeding at 12 months postpartum and a longer duration of breastfeeding in the first year postpartum were both associated with increased HDL-C and decreased TG and VLDL-C at 12 months postpartum.

Bastain TM, Chavez T, Habre R, Hernandez-Castro I, Grubbs B, Toledo-Corral CM, Farzan SF, Lurvey N, Lerner D, Eckel SP, Lurmann F, Lagomasino I, Breton C. Prenatal ambient air pollution and maternal depression at 12 months postpartum in the MADRES pregnancy cohort. Environ Health. 2021

Background: Depression is the leading cause of mental health-related morbidity and affects twice as many women as men. Hispanic/Latina women in the US have unique risk factors for depression and they have lower utilization of mental health care services. Identifying modifiable risk factors for maternal depression, such as ambient air pollution, is an urgent public health priority. We aimed to determine whether prenatal exposure to ambient air pollutants was associated with maternal depression at 12 months after childbirth.

Methods: One hundred eighty predominantly low-income Hispanic/Latina women participating in the ongoing MADRES cohort study in Los Angeles, CA were followed from early pregnancy through 12 months postpartum through a series of phone questionnaires and in-person study visits. Daily prenatal ambient pollutant estimates of nitrogen dioxide (NO2), ozone (O3), and particulate matter (PM10 and PM2.5) were assigned to participant residences using inverse-distance squared spatial interpolation from ambient monitoring data. Exposures were averaged for each trimester and across pregnancy. The primary outcome measure was maternal depression at 12 months postpartum, as reported on the 20-item Center for Epidemiologic Studies-Depression (CES-D) scale. We classified each participant as depressed (n = 29) or not depressed (n = 151) based on the suggested cutoff of 16 or above (possible scores range from 0 to 60) and fitted logistic regression models, adjusting for potential confounders.

Results: We found over a two-fold increased odds of depression at 12 months postpartum associated with second trimester NO2 exposure (OR = 2.63, 95% CI: 1.41-4.89) and pregnancy average NO2 (OR = 2.04, 95% CI: 1.13-3.69). Higher second trimester PM2.5 exposure also was associated with increased depression at 12 months postpartum (OR = 1.56, 95% CI: 1.01-2.42). The effect for second trimester PM10 was similar and was borderline significant (OR = 1.58, 95% CI: 0.97-2.56).

Naya, C.H., Toledo-Corral, C., Chavez, T., Lerner, D., Lurvey, N., Eckel, S.P., Peterson, A., Grubbs, B.H., Dunton, G.F., Breton, C.V., Bastain, T.M. (2020) Third Trimester Cortisol is Positively Associated with Gestational Weight Gain in Pregnant Women with Class One Obesity. International Journal of Obesity. 

Prevalence of pre-pregnancy obesity and excessive gestational weight gain (GWG) are higher among women of color with low SES. Dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis and its end-product, cortisol, during pregnancy is hypothesized to be associated with excessive GWG. However, past studies have produced inconsistent findings and often did not include health disparities populations. This study examined the association between pre-pregnancy body mass index (BMI), third trimester diurnal cortisol, and GWG in low-income, predominantly Hispanic women. The MADRES study is an ongoing prospective cohort study of primarily Hispanic, low-income pregnant women and their children in Los Angeles, California. Data from 176 participants were included in this study. Total cortisol secretion (area under the curve, AUC) was quantified using four salivary cortisol samples (awakening, 30 min after awakening, afternoon, and bedtime) that were collected at home on one day during the third trimester of pregnancy. Moderation of the association between total cortisol and GWG by pre-pregnancy BMI was tested using multiple linear regression with a multiplicative interaction term. There was no association between total cortisol secretion and GWG overall (p = 0.82), but the association between total cortisol and GWG was stronger for women with class 1 pre-pregnancy obesity compared to women with normal pre-pregnancy BMI (interaction term p = 0.04). Results suggest that obesity status before pregnancy may be exacerbating the physiological impact of cortisol on GWG.

Howe CG, Foley HB, Farzan SF, Chavez TA, Johnson M, Meeker JD, Bastain TM, Marsit CJ, Breton CV. Urinary metals and maternal circulating extracellular vesicle microRNA in the MADRES pregnancy cohort. Epigenetics. 2021

Exposure to metals increases risk for pregnancy complications. Extracellular vesicle (EV) miRNA contribute to maternal-foetal communication and are dysregulated in pregnancy complications. However, metal impacts on maternal circulating EV miRNA during pregnancy are unknown. Our objective was to investigate the impact of multiple metal exposures on EV miRNA in maternal circulation during pregnancy in the MADRES Study. Associations between urinary concentrations of nine metals and 106 EV miRNA in maternal plasma during pregnancy were investigated using robust linear regression (N = 231). Primary analyses focused on metal-miRNA associations in early pregnancy (median: 12.3 weeks gestation). In secondary analyses, we investigated associations with late pregnancy miRNA counts (median: 31.8 weeks gestation) in a subset of participants (N = 184) with paired measures. MiRNA associated with three or more metals (PFDR<0.05) were further investigated using Bayesian Kernel Machine Regression (BKMR), an environmental mixture method. Thirty-five miRNA were associated (PFDR<0.05) with at least one metal in early pregnancy. One association (an inverse association between cobalt and miR-150-5p) remained statistically significant when evaluating late pregnancy miRNA counts. Eight miRNA (miR-302b-3p, miR-199a-5p, miR-188-5p, miR-138-5p, miR-212-3p, miR-608, miR-1272, miR-19b-3p) were associated with three metals (barium, mercury, and thallium) in early pregnancy, and their predicted target genes were enriched in pathways important for placental development. Results were consistent when using BKMR. Early pregnancy exposure to barium, mercury, and thallium may have short-term impacts on a common set of EV miRNA which target pathways important for placental development.

Foley HB, Howe CG, Eckel SP, Chavez T, Gevorkian L, Reyes EG, Kapanke B, Martinez D, Xue S, Suglia SF, Bastain TM, Marsit C, Breton CV. Extracellular vesicle-enriched miRNA profiles across pregnancy in the MADRES cohort. PLoS One. 2021 May 12;16(5):e0251259.

MicroRNA (miRNA) circulating in plasma have been proposed as biomarkers for a variety of conditions and diseases, including complications during pregnancy. During pregnancy, about 15-25% of maternal plasma exosomes, a small size-class of EVs, are hypothesized to originate in the placenta, and may play a role in communication between the fetus and mother. However, few studies have addressed changes in miRNA over the course of pregnancy with repeated measures, nor focused on diverse populations. We describe changes in miRNA in early and late pregnancy from the MADRES cohort of primarily low-income Hispanic women based in Los Angeles, CA. miRNA derived from extracellular-vesicles (EVs) were isolated from maternal blood plasma samples collected in early and late pregnancy. In this study, we identified 64 of 130 detectable miRNA which significantly increased with gestational age at the time of collection (GA), and 26 which decreased with GA. Possible fetal sex-specific associations were observed for 30 of these 90 significant miRNA. Predicted gene targets for miRNA significantly associated with GA were identified using MirDIP and were found to be enriched for Gene Ontology categories that included energetic and metabolic processes but were underrepresented in immune-related categories. Circulating EV-associated miRNA during pregnancy are likely important for maternal-fetal communication, and may play roles in supporting and maintaining a healthy pregnancy, given the changing needs of the fetus.

Howe CG, Claus Henn B, Eckel SP, Farzan SF, Grubbs BH, Chavez TA, Hodes TL, Faham D, Al-Marayati L, Lerner D, Quimby A, Twogood S, Richards MJ, Meeker JD, Bastain TM, Breton CV. Prenatal Metal Mixtures and Birth Weight for Gestational Age in a Predominately Lower-Income Hispanic Pregnancy Cohort in Los Angeles. Environmental health perspectives. 2020 Nov 3;128(11):117001.

Background:
Reduced fetal growth increases the risk for adverse health outcomes. Growing evidence suggests that metal exposures contribute to reduced fetal growth, but little is known about the effects of complex metal mixtures.

Objectives:
We investigated the impact of a complex mixture of metals on birth weight for gestational age (BW for GA) in the Maternal and Developmental Risks from Environmental and Social Stressors study, a predominately lower-income Hispanic pregnancy cohort in Los Angeles, California.

Methods:
Cadmium (Cd), cobalt (Co), mercury (Hg), nickel (Ni), molybdenum (Mo), lead (Pb), antimony (Sb), tin (Sn), and thallium (Tl) were measured by inductively coupled plasma mass spectrometry (ICP-MS) in maternal urine samples collected in early pregnancy (median GA: 13.1 wk). Speciated urinary arsenic (As) (inorganic+monomethyl+dimethyl As) was measured by high-performance liquid chromatography coupled to ICP-MS. Primary analyses focused on a mixture of seven metals that have previously been associated individually with fetal growth (i.e., As, Cd, Co, Hg, Ni, Pb, Tl) (n=262). In exploratory analyses, we additionally examined three metals that have been less studied in relation to fetal growth (i.e., Mo, Sb, Sn). Covariate-adjusted Bayesian kernel machine regression was used to investigate metal mixture associations with BW for GA z-scores.

Results:
In primary analyses, Hg and Ni ranked highest as predictors of BW for GA. An inverse linear association was estimated for Hg, whereas a positive association was estimated for Ni at low-to-moderate concentrations. A potential interaction between Hg and Ni was also identified. In our exploratory analysis, Sb ranked highest as a predictor of BW for GA, followed by Hg and Ni.

Conclusions:
Our findings suggest that in this understudied population, Hg may reduce fetal growth, whereas Ni may promote fetal growth. We also identified Sb as a potential metal of concern for this population, which merits additional investigation.

Howe CG, Henn BC, Farzan SF, Habre R, Eckel SP, Grubbs BH, Chavez TA, Faham D, Al-Marayati L, Lerner D, Quimby A, Twogood S, Richards MJ, Meeker JD, Bastain TM, Breton CV. Prenatal Metal Mixtures and Fetal Size in Mid-Pregnancy in the MADRES Study. Environmental Research. 2020 Oct 28:110388.

Background
Fetal growth is predictive of health later in life. Both toxic and essential metals influence fetal growth, but most studies have focused on these elements individually and used birth weight as an indicator of fetal growth. The objective of the current study was to investigate the impact of a mixture of metals on fetal size in mid-pregnancy in a predominately lower income Hispanic pregnancy cohort in Los Angeles.

Methods
For our primary analysis, we focused on six elements that have previously been associated individually with fetal size, including arsenic (As), barium (Ba), cadmium (Cd), mercury (Hg), molybdenum (Mo), and tin (Sn), measured in maternal urine samples collected in early pregnancy (median: 12.4 weeks gestation). In an exploratory analysis, we additionally included cobalt (Co), nickel (Ni), antimony (Sb), and thallium (Tl). Using covariate-adjusted Bayesian Kernel Machine Regression (BKMR) as our main mixture modeling approach, we examined the impact of these metals on fetal biometry measures obtained between 18 and 22 weeks gestation, with a focus on estimated fetal weight (EFW).

Results
BKMR identified Mo and Ba as the mixture components that contributed most to associations with EFW. Linear associations were observed for both metals. An increase in Mo from the 25th to 75th percentile was associated with a 0.114 (95% credible interval (CI): 0.019, 0.247) SD higher EFW, equivalent to a 7.4 g difference. Similar associations were observed between Mo and the other fetal measures evaluated. In contrast, an increase in Ba from the 25th to 75th percentile was associated with a −0.076 (95% CI: 0.217, 0.066) SD lower EFW, equivalent to a 4.9 g difference. Similar inverse associations were observed for Ba in relation to abdominal circumference and biparietal diameter. BKMR also identified a possible interaction between Ba and Mo in relation to head circumference, suggesting that the positive associations between Mo and this outcome may be attenuated at high levels of Ba, which was consistent with findings from linear regression (Pinteraction = 0.03). In an exploratory analysis accounting for a larger mixture of metals, Mo and Ba consistently contributed most to associations with EFW. An inverse association was also identified between Sb and EFW.

Conclusions
Our results suggest that Mo may promote fetal growth, while Ba and Sb may reduce fetal growth, in this population.

Peterson AK, Toledo-Corral CM, Chavez TA, Naya CH, Johnson M, Eckel SP, Lerner D, Grubbs BH, Farzan SF, Dunton GF, Bastain TM, Breton CV. Prenatal Maternal Cortisol Levels and Infant Birth Weight in a Predominately Low-Income Hispanic Cohort. International journal of environmental research and public health. 2020 Jan;17(18):6896.

Infant birth weight influences numerous health outcomes throughout the life course including childhood obesity and metabolic morbidities. Maternal experience of stress, both before and during pregnancy, has been hypothesized to influence fetal growth and birth outcomes. However, these associations currently are not fully understood, due to conflicting results in the published literature. Salivary cortisol is often used as a biological biomarker to assess the diurnal pattern of the hypothalamic–pituitary–adrenal axis (HPA-axis) functioning. Cortisol metrics include both the total cortisol concentration secreted during waking hours, reflected by the area under the curve (AUC), and cortisol dynamics, which include the diurnal cortisol slope (DCS) and the cortisol awakening response (CAR). This study examined the association of these cortisol metrics measured during the third trimester of pregnancy and infant birth weight among 240 mother-infant dyads participating in the Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) pregnancy cohort study, which is predominately comprised of Hispanic low-income women. There were no significant associations with the maternal biological stress response and infant birth weight in this study. More research is needed in larger studies to better understand how the biological stress response influences birth weight in populations facing health disparities.

Farzan SF, Howe CG, Chavez TA, Hodes TL, Johnston JE, Habre R, Dunton G, Bastain TM, and Breton CV. Demographic Predictors of Urinary Arsenic in a Low-Income Predominantly Hispanic Pregnancy Cohort in Los Angeles. Journal of exposure science & environmental epidemiology. 2020 Jul 27:1-4.

Background
Arsenic (As) is a contaminant of top public health concern, due to its range of detrimental health effects. Arsenic exposure has not been well-characterized among the US Hispanic populations and has been particularly understudied in this population during pregnancy.

Methods
As part of the MADRES ongoing pregnancy cohort of predominantly lower-income, Hispanic women in Los Angeles, CA, we examined levels of maternal first trimester urinary As, including total As and As metabolites (inorganic (iAs), monomethylated (MMA) and dimethylated As (DMA)), in relation to participant demographics, lifestyle characteristics, and rice/seafood consumption, to identify factors that may influence As exposure and its metabolites during pregnancy (N = 241).

Results
Total As concentrations ranged from low to high (0.8–506.2 μg/L, mean: 9.0 μg/L, SD: 32.9) in our study population. Foreign-born Hispanic women had 8.6% higher %DMA (95% CI: 3.3%, 13.9%) and −7.7% lower %iAs (95% CI: −12.6%, −2.9%) than non-Hispanic women. A similar trend was observed for US-born Hispanic women. In addition, maternal age was associated with 0.4% higher %iAs (95% CI: 0.1%, 0.6%) and 0.4% lower %DMA (95% CI: −0.7%, −0.1%) per year, which may indicate poor As methylation capacity.

Conclusion
Individual factors may predict As exposure and metabolism in pregnancy, and in turn, greater risk of adverse health effects.

Girguis MS, Li L, Lurmann F, Wu J, Breton C, Gilliland F, Stram D, Habre R. Exposure measurement error in air pollution studies: the impact of shared, multiplicative measurement error on epidemiological health risk estimates. Air Quality, Atmosphere and Health. 2020 May 15.

Spatiotemporal air pollution models are increasingly being used to estimate health effects in epidemiological studies. Although such exposure prediction models typically result in improved spatial and temporal resolution of air pollution predictions, they remain subject to shared measurement error, a type of measurement error common in spatiotemporal exposure models which occurs when measurement error is not independent of exposures. A fundamental challenge of exposure measurement error in air pollution assessment is the strong correlation and sometimes identical (shared) error of exposure estimates across geographic space and time. When exposure estimates with shared measurement error are used to estimate health risk in epidemiological analyses, complex errors are potentially introduced, resulting in biased epidemiological conclusions. We demonstrate the influence of using a three-stage spatiotemporal exposure prediction model and introduce formal methods of shared, multiplicative measurement error (SMME) correction of epidemiological health risk estimates. Using our three-stage ensemble learning-based nitrogen oxides (NOx) exposure prediction model, we quantified SMME. We conducted an epidemiological analysis of wheeze risk in relation to NOx exposure among school-aged children. To demonstrate the incremental influence of exposure modeling stage, we iteratively estimated the health risk using assigned exposure predictions from each stage of the NOx model. We then determined the impact of SMME on the variance of health risk estimates under various scenarios. Depending on the stage of the spatiotemporal exposure model used, we found that wheeze odds ratio ranged from 1.16 to 1.28 for an interquartile range increase in NOx. With each additional stage of exposure modeling, the health effect estimate moved further away from the null (OR = 1). When corrected for observed SMME, the health effects confidence intervals slightly lengthened, but our epidemiological conclusions were not altered. When the variance estimate was corrected for the potential “worst case scenario” of SMME, the standard error further increased, having a meaningful influence on epidemiological conclusions. Our framework can be expanded and used to understand the implications of using exposure predictions subject to shared measurement error in future health investigations.

Howe CG, Farzan SF, Garcia E, Jursa T, Iyer R, Berhane K, Chavez TA, Hodes TL, Grubbs BH, Funk WE, Smith DR, Bastain TM, Breton CV. Arsenic and birth outcomes in a predominately lower income Hispanic pregnancy cohort in Los Angeles. Environmental Research. 2020 Feb 27:109294.

Prenatal arsenic exposure has been associated with reduced fetal growth and increased risk for preterm birth, but most studies have been conducted in highly exposed populations outside the U.S. or in non-Hispanic populations in the rural U.S. The objectives of the current study were to: 1) examine the impact of early pregnancy exposure to arsenic on birth weight and gestational age at birth in a predominately lower income Hispanic pregnancy cohort in urban Los Angeles and 2) compare multiple biomarkers of arsenic exposure (blood, urine, and hair) assessed in early pregnancy (mean ± SD gestational age at biospecimen collection: 14 ± 4 weeks). Total arsenic (blood, hair) was measured by ICP-MS and speciated arsenic (urine) was measured by HPLC coupled to ICP-MS. Associations between log2-transformed arsenic measures and birth outcomes were evaluated using multivariable linear regression. A doubling in hair arsenic was associated with a 72.2 g (95% CI: −144.3, −0.1, P = 0.05) lower birth weight, after adjusting for potential confounders and gestational age at birth. A similar but non-significant trend was observed for blood arsenic, but not urine arsenic. The inverse association between hair arsenic and birth weight was more pronounced among infants whose mothers gained greater amounts of weight during pregnancy (Pinteraction = 0.02). The association between urinary monomethyl arsenic and GA at birth differed by pre-pregnancy BMI (Pinteraction<0.01). This study provides evidence that even at relatively low levels of exposure, arsenic exposure (measured in hair samples collected in early pregnancy) may adversely affect fetal growth in this understudied population, particularly in combination with greater gestational weight gain. Future studies with larger sample sizes are needed to confirm these findings and to further investigate some of the inconsistencies observed for the different arsenic biomarkers evaluated.

Yi L, Wilson JP, Mason TB, Habre R, Wang S, Dunton GF. Methodologies for assessing contextual exposure to the built environment in physical activity studies: A systematic review. Health & Place. 2019 Nov 1;60:102226.

Growing research has integrated Global Positioning Systems (GPS), Geographic Information Systems (GIS), and accelerometry in studying effects of built environment on physical activity outcomes. This systematic review aimed to summarize current geospatial methods of assessing contextual exposure to the built environment in these studies. Based on reviewing 79 eligible articles, methods were identified and grouped into three main categories based on similarities in their approaches as follows: domain-based (67% of studies), buffer-based (22%), and activity space-based (11%). Additionally, technical barriers and potential sources of uncertainties in each category were discussed and recommendations on methodological improvements were made.

Bastain TM, Chavez T, Habre R, Girguis MS, Grubbs B, Toledo-Corral C, Amadeus M, Farzan SF, Al-Marayati L, Lerner D, Noya D, Quimby A, Twogood S, Wilson M, Chatzi L, Cousineau M, Berhane K, Eckel SP, Lurmann F, Johnston J, Dunton GF, Gilliland F, Breton CV. Study design, protocol and profile of the Maternal And Developmental Risks from Environmental and Social Stressors (MADRES) pregnancy cohort: A prospective cohort study in predominantly low-income Hispanic women in urban Los Angeles. BMC pregnancy and childbirth. 2019 Dec 1;19(1):189.

Background
The burden of childhood and adult obesity disproportionally affects Hispanic and African-American populations in the US, and these groups as well as populations with lower income and education levels are disproportionately affected by environmental pollution. Pregnancy is a critical developmental period where maternal exposures may have significant impacts on infant and childhood growth as well as the future health of the mother. We initiated the “Maternal And Developmental Risks from Environmental and Social Stressors (MADRES)” cohort study to address critical gaps in understanding the increased risk for childhood obesity and maternal obesity outcomes among minority and low-income women in urban Los Angeles.

Methods
The MADRES cohort is specifically examining whether pre- and postpartum environmental exposures, in addition to exposures to psychosocial and built environment stressors, lead to excessive gestational weight gain and postpartum weight retention in women and to perturbed infant growth trajectories and increased childhood obesity risk through altered psychological, behavioral and/or metabolic responses. The ongoing MADRES study is a prospective pregnancy cohort of 1000 predominantly lower-income, Hispanic women in Los Angeles, CA. Enrollment in the MADRES cohort is initiated prior to 30 weeks gestation from partner community health clinics in Los Angeles. Cohort participants are followed through their pregnancies, at birth, and during the infant’s first year of life through a series of in-person visits with interviewer-administered questionnaires, anthropometric measurements and biospecimen collection as well as telephone interviews conducted with the mother.

Discussion
In this paper, we outline the study rationale and data collection protocol for the MADRES cohort, and we present a profile of demographic, health and exposure characteristics for 291 participants who have delivered their infants, out of 523 participants enrolled in the study from November 2015 to October 2018 from four community health clinics in Los Angeles. Results from the MADRES cohort could provide a powerful rationale for regulation of targeted chemical environmental components, better transportation and urban design policies, and clinical recommendations for stress-coping strategies and behavior to reduce lifelong obesity risk.

Girguis MS, Li L, Lurmann F, Wu J, Urman R, Rappaport E, Breton C, Gilliland F, Stram D, Habre R. Exposure measurement error in air pollution studies: A framework for assessing shared, multiplicative measurement error in ensemble learning estimates of nitrogen oxides. Environment international. 2019 Apr 1;125:97-106.

Background
Increasingly ensemble learning-based spatiotemporal models are being used to estimate residential air pollution exposures in epidemiological studies. While these machine learning models typically have improved performance, they suffer from exposure measurement error that is inherent in all models. Our objective is to develop a framework to formally assess shared, multiplicative measurement error (SMME) in our previously published three-stage, ensemble learning-based nitrogen oxides (NOx) model to identify its spatial and temporal patterns and predictors.

Methods
By treating the ensembles as an external dosimetry system, we quantified shared and unshared, multiplicative and additive (SUMA) measurement error components in our exposure model. We used generalized additive models (GAMs) with a smooth term for location to identify geographic locations with significantly elevated SMME and explain their spatial and temporal determinants.

Results
We found evidence of significant shared and unshared multiplicative error (p < 0.0001) in our ensemble-learning based spatiotemporal NOx model predictions. Unshared multiplicative error was 26 times larger than SMME. We observed significant geographic (p < 0.0001) and temporal variation in SMME with the majority (43%) of predictions with elevated SMME occurring in the earliest time-period (1992–2000). Densely populated urban prediction regions with complex air pollution sources generally exhibited highest odds of elevated SMME.

Conclusions
We developed a novel statistical framework to formally evaluate the magnitude and drivers of SMME in ensemble learning-based exposure models. Our framework can be used to inform building future improved exposure models.

Howe CG, Zhou M, Wang X, Pittman GS, Thompson IJ, Campbell MR, Bastain TM, Grubbs BH, Salam MT, Hoyo C, Bell DA, Smith AD, Breton CV. Associations between Maternal Tobacco Smoke Exposure and the Cord Blood CD4+ DNA Methylome. Environmental health perspectives. 2019 Apr 30;127(4):047009.

Background:
Maternal tobacco smoke exposure has been associated with altered DNA methylation. However, previous studies largely used methylation arrays, which cover a small fraction of CpGs, and focused on whole cord blood.

Objectives:
The current study examined the impact of in utero exposure to maternal tobacco smoke on the cord blood CD4+ DNA methylome.

Methods:
The methylomes of 20 Hispanic white newborns (n=10 exposed to any maternal tobacco smoke in pregnancy; n=10 unexposed) from the Maternal and Child Health Study (MACHS) were profiled by whole-genome bisulfite sequencing (median coverage: 6.5×). Statistical analyses were conducted using the Regression Analysis of Differential Methylation (RADMeth) program because it performs well on low-coverage data (minimizes false positives and negatives).

Results:
We found that 10,381 CpGs were differentially methylated by tobacco smoke exposure [neighbor-adjusted p-values that are additionally corrected for multiple testing based on the Benjamini-Hochberg method for controlling the false discovery rate (FDR) (pFDR)<0.05]. From these CpGs, RADMeth identified 557 differentially methylated regions (DMRs) that were overrepresented (p<0.05) in important regulatory regions, including enhancers. Of nine DMRs that could be queried in a reduced representation bisulfite sequencing (RRBS) study of adult CD4+ cells (n=9 smokers; n=10 nonsmokers), four replicated (p<0.05). Additionally, a CpG in the promoter of SLC7A8 (percent methylation difference: −9.4% comparing exposed to unexposed) replicated (p<0.05) in an EPIC (Illumina) array study of cord blood CD4+ cells (n=14 exposed to sustained maternal tobacco smoke; n=16 unexposed) and in a study of adult CD4+ cells across two platforms (EPIC: n=9 smokers; n=11 nonsmokers; 450K: n=59 smokers; n=72 nonsmokers).

Conclusions:
Maternal tobacco smoke exposure in pregnancy is associated with cord blood CD4+ DNA methylation in key regulatory regions, including enhancers. While we used a method that performs well on low-coverage data, we cannot exclude the possibility that some results may be false positives. However, we identified a differentially methylated CpG in amino acid transporter SLC7A8 that is highly reproducible, which may be sensitive to cigarette smoke in both cord blood and adult CD4+ cells.

O’Connor SG, Habre R, Bastain TM, Toledo-Corral CM, Gilliland FD, Eckel SP, Cabison J, Naya CH, Farzan SF, Chu D, Chavez TA, Breton CV, Dunton GF. Within-subject effects of environmental and social stressors on pre-and post-partum obesity-related biobehavioral responses in low-income Hispanic women: protocol of an intensive longitudinal study. BMC Public Health 2019;19(1):253.

Background
Disproportionately high rates of maternal overweight and obesity among the Hispanic population before, during, and after pregnancy pose serious health concerns for both mothers (e.g., preeclampsia, gestational diabetes, weight retention) and children (e.g., elevated lifelong obesity risk). A growing body of evidence implicates environmental exposures (e.g., air pollution, metals) and social stressors (e.g., poverty, violence) in contributing to obesity-related biobehavioral processes, such as physical activity, dietary intake, perceived stress, and cortisol regulation. However, current understanding of the role of environmental exposures and social stressors on obesity-related biobehavioral processes is limited by infrequent, inter-individual measurement, and lack of personal exposure monitoring.

Methods
The “Maternal and Developmental Risks from Environmental and Social Stressors” (MADRES) real-time and personal sampling study examines the within-subject day-level effects of environmental and social stressors on maternal pre- and post-partum obesity-related biobehavioral responses. Among a cohort of 65 low-income, Hispanic women in urban Los Angeles, this study uses innovative personal, real-time data capture strategies (e.g., ecological momentary assessment [EMA], personal exposure monitoring, geolocation monitoring, accelerometry) to repeatedly assess obesity-related processes during the 1st and 3rd trimester, and at 4–6 months postpartum. Day-level effects of environmental exposures and social stressors on women’s physical activity, diet, perceived stress and salivary cortisol measured across repeated days will be tested using multilevel modeling.

Discussion
Hispanic women of childbearing age bear a disproportionately high burden of obesity, and this population is also unduly exposed to numerous obesogenic settings. By using innovative real-time data capture strategies, the current study will uncover the daily impacts of environmental and social stressor exposures on women’s obesity-related biobehavioral responses, which over time can lead to excessive gestational weight gain, postpartum weight retention and can pose serious consequences for both mother and child. Findings from the real-time and personal sampling study will identify key mechanistic targets for policy, clinical, and programmatic interventions, with the potential for broad-reaching public health impacts.

Alderete TL, Song AY, Bastain T, Habre R, Toledo-Corral CM, Salam MT, Lurmann F, Gilliland FD, Breton CV. Prenatal traffic-related air pollution exposures, cord blood adipokines and infant weight. Pediatric obesity. 2018 Jun;13(6):348-56.

Objective
Studies suggest that prenatal exposure to traffic-related air pollution (TRAP) may contribute to childhood obesity. While exact mechanisms for this association are unknown, circulating adipokines are hypothesized to contribute to early-life weight gain.

Methods
The Maternal and Child Health Study birth cohort included 136 women from the Los Angeles County + University of Southern California Medical Center. This study estimated prenatal residential TRAP exposure and used linear regression analysis to examine associations between adipokines with TRAP exposure and infant weight change (birth to 6 months).

Results
A one standard deviation (1-SD: 2 ppb) increase in prenatal non-freeway NOx was associated with 33% (p=0.01) higher leptin and 9% higher high molecular weight (HMW) adiponectin levels (p=0.07) in cord blood. Leptin levels were 71% higher in mothers who lived <75 meters than those living >300 meters from major roadways (p=0.03). A 1-SD (10 ng/ml) increase in leptin was associated with a significant increase in infant weight change in females (0.62 kg, p=0.02) but not males (0.11 kg, p=0.48).

Conclusions
Higher TRAP exposures were associated with higher cord blood levels of leptin and HMW adiponectin. These adipokines were associated with increased infant weight change in females, which may have implications for future obesity risk.

Felix JF, Joubert  BR, Baccarelli AA, Sharp GC, Almquist C, Annesi-Maesano I, Arshad H, Baiz N, Bakermans-Kranenburg MJ, Bakulski KM, Binder EB, Bouchard L, Breton CV,  Brunekreef B, Brunst KJ, Burchard EG, Bustamante M, Chatzi L … Agha G, Relton CL, Jaddoe VWV, London SJ. Cohort Profile: Pregnancy and Childhood Epigenetics (PACE) Consortium. International journal of epidemiology. 2018 Feb 1;47(1):22-3u.

No abstract available. Read the full text here.

Alderete TL, Habre R, Toledo-Corral CM, Berhane K, Chen Z, Lurmann F, Weigensberg MJ, Goran MI, Gilliland FD. Longitudinal associations between ambient air pollution with insulin sensitivity, β-cell function, and adiposity in Los Angeles Latino children. Diabetes. 2017 Jul 1;66(7):1789-96.

Evidence suggests that ambient air pollution (AAP) exposure may contribute to the development of obesity and type 2 diabetes. The objective of this study was to determine whether exposure to elevated concentrations of nitrogen dioxide (NO2) and particulate matter with aerodynamic diameter <2.5 (PM2.5) had adverse effects on longitudinal measures of insulin sensitivity (SI), β-cell function, and obesity in children at high risk for developing diabetes. Overweight and obese Latino children (8–15 years; n = 314) were enrolled between 2001 and 2012 from Los Angeles, CA, and followed for an average of 3.4 years (SD 3.1 years). Linear mixed-effects models were fitted to assess relationships between AAP exposure and outcomes after adjusting for covariates including body fat percent. Higher NO2 and PM2.5 were associated with a faster decline in SI and a lower SI at age 18 years, independent of adiposity. NO2 exposure negatively affected β-cell function, evidenced by a faster decline in disposition index (DI) and a lower DI at age 18 years. Higher NO2 and PM2.5 exposures over follow-up were also associated with a higher BMI at age 18 years. AAP exposure may contribute to development of type 2 diabetes through direct effects on SI and β-cell function.

Xu Y., Yi L., Cabison J., O’Sharkey K., Chavez T., Lurmann F., Bastain T.M., Breton C.V., Wilson J.P., Habre R. (2021, April). Using GPS-derived Time-Activity Patterns to Estimate Personal Particulate Air Pollution Exposure in MADRES. Abstract presented at the American Association of Geographers 2021 Annual Meeting.

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Yi L., Habre R., Xu Y., Mason T., Naya C.H., Chu D., Chavez T., Wilson J.P., Bastain T.M., Breton C.V., Dunton G.F. (2021, April). A Study of Context-Specific Physical Activity Patterns of Low-Income Hispanic Women During Pregnancy Using GPS And Accelerometer Data. Abstract presented at the 2021 Annual Active Living Conference.

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Yi, L., Xu Y, O’Connor S.G., Cabison J., Chu D., Chavez T., Mason T.B., Bastain T.M.,. Breton C.V., Dunton G.F.,  Wilson J.P., and Habre R. (2021, April). Integrating mobility and time-activity patterns in assessing environmental exposures during pregnancy and early postpartum. Abstract presented at the American Association of Geographers 2021 Annual Meeting.

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Xu Y., Cabison J., Chavez T., Wilson J.P., Bastain T.M., Breton C.V., Habre R. (2020, September). Sources of Personal PM2.5 Exposure in the MADRES Cohort during the Third Trimester of Pregnancy. Abstract presented at the International Society of Exposure Science 2020 Annual Meeting.

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Habre, R., Yi, L., Xu, Y., Naya, C., O’Connor, S., Cabison, J., Chu, D., Mason, T., Chavez, T., Bastain, T., Breton, C., Dunton, G. (2020, September). Personal PM2.5 air pollution exposure, time-activity patterns and momentary geospatial exposures across pregnancy and early postpartum in low income, Hispanic women. Abstract presented at the International Society of Exposure Science 2020 Annual Meeting.

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Li, L.,  Girguis, M., Lurmann, F., Pavlovic, N., Franklin, M., Wu, J., Oman, L., Breton, C., Gilliland, F., Habre, R. (2020, September). Ensemble-Based Deep Learning for Estimating PM2.5 over California. Abstract presented at the International Society of Exposure Science 2020 Annual Meeting.

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Bastain, T., Chavez, T., Habre, R., Lurmann, F., Farzan, S., Grubbs, B., Dunton, G., Lagomasino, I., Eckel, S., Breton, C. (2020, August). Prenatal Ambient Air Pollutants and Maternal Depressive Symptoms at 12 months Postpartum. Abstract presented at the 32nd Annual Conference of the International Society for Environmental Epidemiology.

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Breton, C.V., Peterson, A.K., Habre, R., Lurmann, F., Amin, M., Eckel, S.P., Grubbs, B., Walker, D., Grant, E., Lerner, D., Al-Marayati, L., Quimby, A., Twogood, S., Bastain, T. (2020, August). Prenatal Ambient Air Pollutants Influence Fetal Blood Flow and Shunting to the Brain in the Third Trimester. Abstract presented at the 32nd Annual Conference of the International Society for Environmental Epidemiology.

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Howe, C.G., Claus Henn, B., Eckel, S.P., Farzan, S.F, Grubbs, B.H., Fernandez, J., Meeker, J.D., Bastain, T.M., Breton, C.V. (2020, August). Prenatal metal mixtures and birth weight for gestational age in a predominately lower income Hispanic pregnancy cohort. Abstract presented at the 32nd Annual Conference of the International Society for Environmental Epidemiology.

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Mohazzab-Hosseinian, S., Howe, C.G., Foley, H., Faham, D., Chavez, T., Weisenberger, D., Bastain, T.M., Breton, C.V. (2020, August). Antibiotic Use during Pregnancy and the Maternal Epigenome. Abstract presented at the 32nd Annual Conference of the International Society for Environmental Epidemiology.

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Peterson A.K., Hodes T., Chavez T.A., Howland, S., Grubbs B., Chatzi L., Gilliland F., Bastain T.M., Breton C.V. (2020, August). Prenatal PFAS exposure influences infant lean and fat mass. Abstract presented at the 32nd Annual Conference of the International Society for Environmental Epidemiology.

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Chavez T.A., Habre R., Farzan S., Toledo-Corral C., Grubbs B., Eckel S., Dunton G.F., Breton C., and Bastain T.M. (2020, March). Prenatal Traffic-Related Air Pollution Exposure and Postpartum Depressive Symptoms in the MADRES Pregnancy Cohort. Abstract accepted at the 59th Annual Meeting of the Society of Toxicology, Anaheim, CA.

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Johnson, M., Chavez, T., Grubbs, B., Berhane, K., Gilliland, F., Habre, R., Bastain, T., and Breton, C. (2020, March). Prenatal Air Pollutant Exposure, Perceived Stress and 12-Month Infant Growth in the MADRES Cohort. Abstract accepted at the 59th Annual Meeting of the Society of Toxicology, Anaheim, CA.

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Mohazzab-Hosseinian, S., Howe, C., Bastain, T., Chavez, T., Breton, C. (2020, March). Epigenetic Effects of Gestational Diabetes: A Prospective Study. Abstract accepted at the 59th Annual Meeting of the Society of Toxicology, Anaheim, CA.

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Naya, C. H., Peterson, A., Chavez, T., Eckel, S. P., Toledo-Corral, C., Mason, T., Bastain, T., Breton, C., & Dunton, G.F. (2019, November). Cortisol awakening response and weight during third trimester pregnancy among predominantly low-income Hispanic mothers. Abstract presented at the 2019 Obesity Week, Las Vegas, NV.

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Peterson, A. K., Naya, C. H., Chavez, T. A., Toledo-Corral, C. M., Habre, R., Howland, S., & Bastain, T. M. (2019, November). The relationship between prenatal stress and newborn body composition. Abstract presented at the 2019 Obesity Week, Las Vegas, NV.

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Howe, C. G., Farzan, S. F., Chavez, T. A., Hodes, T., Bastain, T. L., & Breton, C. V. (2019, October). Arsenic exposure and birth outcomes in a predominately low-income Hispanic pregnancy cohort in Los Angeles. Abstract presented at the 11th DOHaD World Congress, Melbourne, Australia.

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Girguis, M. S., Bastain, T. M., Chavez, T., Gilliland, F., Breton, C., & Habre, R. (2019, July). Where you live matters: Assessing the relationship of socio-environmental neighborhood clusters with stress and depression during pregnancy. Abstract presented at the 31st Annual Conference of the International Society for Environmental Epidemiology, Utrecht, the Netherlands.

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Habre, R., O’Connor, S., Girguis, M. S., Cabison, J., Chu, D., Chavez, T., Bastain, T., Breton, C., & Dunton G. (2019, July). Personal PM2.5 air pollution exposure and mobility patterns in pregnant, low income Hispanic women in MADRES. Abstract presented at the 31st Annual Conference of the International Society for Environmental Epidemiology, Utrecht, the Netherlands.

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Peterson, A. K., Chavez, T. A., Toledo-Corral, C. M., Naya, C. H., Dunton, G. F., Bastain, T. M., & Breton, C. (2019, July). Exploring the association of birth weight with maternal measured and perceived stress. Abstract presented at the 10th Biennial Childhood Obesity Conference, Anaheim, CA.

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Song, A. Y., Habre, R., Girguis, M., Chavez, T., Lurmann, F., Grubbs, B. H., Bastain, T., & Breton, C. (2019, July). Identifying sensitive windows of prenatal exposure to ambient air pollution with birthweight using a distributed lag model. Abstract presented at the 31st Annual Conference of the International Society for Environmental Epidemiology, Utrecht, the Netherlands.

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Song, A. Y., Habre, R., Girguis, M., Dunton, G., Chavez, T., Lurmann, F., Grubbs, B. H., Bastain, T., & Breton, C. (2019, July). Ambient air pollution with birthweight: Modification by maternal stress. Abstract presented at the 10th Biennial Childhood Obesity Conference, Anaheim, CA.

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Bermudez-Foley, H., & Breton, C. (2019, June). miRNA profiles and psychosocial stress during pregnancy in a cohort of urban Hispanic mothers. Abstract presented at the 14th Annual Texas Conference on Health Disparities: Social Epigenomics and Health Disparities, Fort Worth, TX.

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Chavez, T., Bastain, T., & Breton, C. (2019, June). Maternal obesity and risk of gestational diabetes in the MADRES pregnancy cohort: A prospective cohort study in predominantly low-income Hispanic women in urban Los Angeles. Abstract presented at the Annual Meeting of the Society of Epidemiological Research, Minneapolis, MN.

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Mason, T. B., O’Connor, S. G., Cabison, J., Bastain, T., Naya, C. H., Chu, D., Eckel, S. P., Breton, C. V., & Dunton, G. F. (2019, June). Bi-directional associations of affective states and energy balance behaviors among pregnant women using ecological momentary assessment. Abstract presented at the 6th Society for Ambulatory Assessment Conference, Syracuse, NY.

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Girguis, M. S., Bastain, T. M., Chavez, T., Johnston, J. Toledo-Corral, C., Dunton, G., Breton, C., & Habre, R. (2019, May). Where you live matters: Socio-environmental neighborhood level exposome profiles and stress during pregnancy. Abstract presented at the 2nd Annual UNIBS/ISMMS Collaborative Conference, 2019 Exposome Symposium: Emerging Science and Technology for Effective Prevention and Healthy Outcomes, Brescia, Italy.

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Peterson, A. K., Chavez, T. A., Habre, R., Howland, S., Gilliland, F., Bastain, T. M., & Breton, C. V. (2019, May). Preliminary data analysis on novel technology to assess adolescent fat mass. Abstract presented at the Body Composition Measurements from Birth through 5 years: Challenges, Gaps, and Existing and Emerging Technologies of The National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD.

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Toledo-Corral, C. M., Naya, C., Chavez, T., Habre, R., Bastain, T., Dunton, G., Gilliland, F.D., & Breton, C. (2019, March). Characterizing diurnal cortisol patterns of 3rd trimester pregnant women in Los Angeles. Abstract presented at the 77th Annual Scientific Meeting of the American Psychosomatic Society, Vancouver, British Columbia. 

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Girguis, M. S., Bastain, T. M., Chavez, T., Johnston, J. Toledo-Corral, C., Dunton, G., Breton, C., & Habre, R. (2019, January). Where you live matters: Assessing socio-environmental neighborhood level exposures of MADRES participants. Abstract presented at the NIH-EPA Centers of Excellence on Environmental Health Disparities Research Annual Grantees Meeting, Baltimore, MD.

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Howe, C. G., Farzan, S. F., Eckel, S. P., Hodes, T., Chavez, T. A., Bastain, T. L., Gilliland, F. D., & Breton, C. V. (2019, January). Rice and seafood intake and urine arsenic in the MADRES Pregnancy cohort. Abstract presented at the NIH-EPA Centers of Excellence on Environmental Health Disparities Research Annual Grantees Meeting, Baltimore, MD.

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Bastain, T., Gao, L., Toledo-Corral, C., Chavez, T., Habre, R., Farzan, S., Grubbs, B., Johnston, J., Dunton, G., Gilliland, F., & Breton, C. (2018, August). Early descriptive results from the Maternal And Developmental Risks from Environmental and Social Stressors (MADRES) pregnancy cohort study. Abstract presented at the ISES-ISEE 2018 Joint Annual Meeting, Ottawa, Canada.

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Girguis, M. S., Li, L., Lurmann, F., Wu, J., Urman, R., Rappaport, E., Breton, C., Gilliland, F., Stram, D., & Habre, R. (2018, August). Assessment of shared and unshared exposure measurement error in ensemble learning estimates of nitrogen oxides and its implications on epidemiological findings in air pollution studies. Abstract presented at the ISES-ISEE 2018 Joint Annual Meeting, Ottawa, Canada.

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Toledo-Corral, C. M., Gao, L., Chavez, T., Grubbs, B., Habre, R., Bastain, T. M., Dunton, G., Gilliland, F. D., & Breton, C. (2018, August). Correlates of stress and depression in early pregnancy in a low-income minority population. Abstract presented at the ISES-ISEE 2018 Joint Annual Meeting, Ottawa, Canada.

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O’Connor, S.G., Wai-Quan Cabison, J., Ke, W., Breton, C.V., Bastain, T., & Dunton, G.F. (2017, December). Ecological momentary assessment methods to measure stress, mood, and weight-related behaviors in low-Income, Hispanic, post-partum women. Abstract presented at the NIH-EPA Centers of Excellence on Environmental Health Disparities Research Annual Grantees Meeting, Albuquerque, New Mexico.

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O’Connor, S.G., Wai-Quan Cabison, J., Ke, W., Breton, C.V., Bastain, T., & Dunton, G.F. (2017, March). Using ecological momentary assessment methods to measure stress and weight-related behaviors in Hispanic post-partum women. Abstract presented at the 38th Annual Meeting of the Society of Behavioral Medicine, San Diego, CA.

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Breton, C., Bastain, T. M., Dunton, G., Grubbs, B., Eckel, S., Berhane, K., Toledo-Corral, Habre, R., Johnston, J., & Gilliland, F. (2016, September). Maternal And Developmental Risks from Environmental and Social Stressors: An environmental health disparities center. Abstract presented at the 28th Annual Conference of the International Society for Environmental Epidemiology, Rome Italy.

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Habre, R., Bastain, T. M., Dunton, G., Eckel, S., Gilliland, F., & Breton, C. (2016, September). Personal air pollution monitoring in the MADRES cohort of pregnant women: Challenges and lessons learned. Abstract presented at the 28th Annual Conference of the International Society for Environmental Epidemiology, Rome Italy.