Publications (20)100.2 Total impact
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Article: Residential Proximity to Methyl Bromide Use and Birth Outcomes in an Agricultural Population in California.
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ABSTRACT: BACKGROUND: Methyl bromide, a fungicide often used in strawberry cultivation, is of concern for residents who live near agricultural applications because of its toxicity and potential for drift. Little is known about the effects of methyl bromide exposure during pregnancy. OBJECTIVE: We investigated the relationship between residential proximity to methyl bromide use and birth outcomes. METHODS: Participants were from the CHAMACOS study (n=442), a longitudinal cohort study examining the health effects of environmental exposures on pregnant women and their children in an agricultural community in Northern California. Using data from the California Pesticide Use Reporting system, we employed a geographic information system (GIS) to estimate the amount of methyl bromide applied within 5 km of a woman's residence during pregnancy. Multiple linear regression models were used to estimate associations between trimester-specific proximity to use and birth weight, length, head circumference, and gestational age. RESULTS: High methyl bromide use (vs. no use) within 5 km of the home during the second trimester was negatively associated with birth weight (β= -113.1 g; CI: -218.1, -8.1), birth length (β= -0.85 cm; CI: -1.44, -0.27), and head circumference (β= -0.33 cm; CI: -0.67, 0.01). These outcomes were also associated with moderate methyl bromide use during the second trimester. Negative associations with fetal growth parameters were stronger when larger (5 km and 8 km) versus smaller (1 km and 3 km) buffer zones were used to estimate exposure. CONCLUSIONS: Residential proximity to methyl bromide use during the second trimester was associated with markers of restricted fetal growth in our study.Environmental Health Perspectives 04/2013; · 7.04 Impact Factor -
Article: In Utero DDT and DDE Exposure and Obesity Status of 7-Year-Old Mexican-American Children in the CHAMACOS Cohort.
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ABSTRACT: BACKGROUND: In utero exposure to endocrine disrupting compounds including dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethylene (DDE) has been hypothesized to increase risk of obesity later in life. OBJECTIVES: The Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study is a longitudinal birth cohort of low-income Latinas living in a California agricultural community. We examined the relation of in utero DDT and DDE exposure to child obesity at 7 years. We also examined the trend with age (2, 3½, 5, 7 years) in the exposure-obesity relation. METHODS: We included 270 children with o,p'-DDT, p,p'-DDT, and p,p'-DDE concentrations measured in maternal serum during pregnancy (ng/g lipid) and complete 7-year follow-up data including weight (kg) and height (cm). Body mass index (BMI, kg/m(2)) was calculated and obesity was defined as ≥ 95th percentile on the sex-specific BMI-for-age CDC 2000 growth charts. RESULTS: At 7 years, 96 (35.6%) children were obese. A 10-fold increase in o,p'-DDT, p,p'-DDT, or p,p'-DDE, was non-significantly associated with increased odds of obesity (o,p'-DDT adj-OR = 1.17, 95% CI: 0.75, 1.82; p,p'-DDT adj-OR = 1.19, 95% CI: 0.81, 1.74; p,p'-DDE adj-OR = 1.22, 95% CI: 0.72, 2.06). With increasing age at follow-up, we observed a significant trend towards a positive association between DDT and DDE exposure and odds of obesity. CONCLUSION: We did not find a significant positive relation between in utero DDT and DDE exposure and obesity status of 7-year-old children. However, given the observed trend with age, continued follow-up will be informative.Environmental Health Perspectives 03/2013; · 7.04 Impact Factor -
Article: Prenatal and Postnatal Bisphenol A Exposure and Body Mass Index in Childhood in the CHAMACOS Cohort.
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ABSTRACT: BACKGROUND: Bisphenol A (BPA), a widely used endocrine-disrupting chemical, has been associated with increased body weight and fat deposition in rodents. OBJECTIVES: We examined whether prenatal and postnatal urinary BPA concentrations were associated with body mass index (BMI), waist circumference, percent body fat, and obesity in 9-year-old children (N=311) in the CHAMACOS longitudinal cohort study. METHODS: BPA was measured in spot urine samples collected from mothers twice during pregnancy and from children at 5 and 9 years of age. RESULTS: Prenatal urinary BPA concentrations were associated with decreased BMI at age 9 in girls but not boys. Among girls, being in the highest tertile of prenatal BPA concentrations was associated with decreased BMI Z-score (β = -0.47, 95% Confidence Interval (CI): -0.87, -0.07) and percent body fat (β = -4.36, 95% CI: -8.37, -0.34) and decreased odds of overweight/obesity (Odds Ratio (OR) = 0.37, 95% CI: 0.16, 0.91) compared to girls in the lowest tertile. These findings were strongest in pre-pubertal girls. Urinary BPA concentrations at age 5 years were not associated with any anthropometric parameters at age 5 or 9 years, but BPA concentrations at age 9 were positively associated with BMI, waist circumference, fat mass, and overweight/obesity at age 9 in boys and girls. CONCLUSIONS: Consistent with other cross-sectional studies, higher urinary BPA concentrations at age 9 were associated with increased adiposity at 9 years. However, increasing BPA concentrations in mothers during pregnancy were associated with decreased BMI, body fat, and overweight/obesity among their daughters at age 9.Environmental Health Perspectives 02/2013; · 7.04 Impact Factor -
Article: Associations between perinatal factors and adiponectin and leptin in 9-year-old Mexican-American children.
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ABSTRACT: What is already known about this subject Mexican-American children are at particularly high risk of obesity. Features of the perinatal environment, including maternal nutrition, anthropometry, glucose tolerance and growth rate during infancy are implicated in programming of obesity in the offspring. What this study adds Greater rate of weight or length gain in the first 6 months of life is associated with lower 9-year child adiponectin levels, adjusting for 9-year child BMI. Nine-year-old child adipokine levels are strongly related to those of their mothers'. OBJECTIVES: To (i) determine whether perinatal factors (including maternal anthropometry and nutrition and early life growth measures) are associated with adiponectin and leptin levels in 9-year-old children, and (ii) assess relationships between adiponectin, leptin and concurrent lipid profile in these children. METHODS: We measured plasma adiponectin and leptin for 146 mothers-9-year-old child pairs from the ongoing longitudinal birth cohort followed by the Center for the Health Assessment of Mothers and Children of Salinas. Data on perinatal factors, including sociodemographics, maternal anthropometry and nutrition, and early life child growth were collected during pregnancy, birth and 6-month visits. RESULTS: Greater rate of weight and length gain during the first 6 months of life were associated with lower adiponectin in 9-year-olds (β = -2.0, P = 0.04; β = -8.2, P = 0.02, respectively) adjusting for child body mass index (BMI). We found no associations between child adipokine levels and either maternal calorie, protein, total fat, saturated fat, fibre, sugar-sweetened beverage consumption during pregnancy or children's concurrent sugar-sweetened beverage and fast food intake. Lipid profile in 9-year-old children closely reflected adiponectin but not leptin levels after adjustment for child BMI. Additionally, we report that child adipokine levels were closely related to their mothers' levels at the 9-year visit. CONCLUSION: Overall, our results support the hypothesis that early life factors may contribute to altered adipokine levels in children.Pediatric obesity. 01/2013; -
Article: In Utero and Childhood Polybrominated Diphenyl Ether (PBDE) Exposures and Neurodevelopment in the CHAMACOS Study.
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ABSTRACT: OBJECTIVE: California children's exposures to polybrominated diphenyl ether flame retardants (PBDEs) are among the highest worldwide. PBDEs are known endocrine disruptors and neurotoxicants in animals. Here, we investigate the relation of in utero and child PBDE exposure to neurobehavioral development among participants in CHAMACOS, a California birth cohort. METHODS: We measured PBDEs in maternal prenatal and child serum samples and examined the association of PBDE concentrations with children's attention, motor functioning, and cognition at ages 5 (N=323) and 7 years (N=310). RESULTS: Maternal prenatal PBDE concentrations were associated with impaired attention as measured by a continuous performance task at age 5 and maternal report at ages 5 and 7, with poorer fine motor coordination - particularly in the non-dominant hand - at both age points, and with decrements in Verbal and Full-Scale Intelligence Quotient (IQ) at age 7. Child age 7 PBDE concentrations were significantly or marginally associated with concurrent teacher reports of attention problems and decrements in Processing Speed, Perceptual Reasoning, Verbal Comprehension, and Full Scale IQ. These associations were not altered by adjustment for birthweight, gestational age, or maternal thyroid hormone levels. CONCLUSIONS: Both prenatal and childhood PBDE exposures were associated with poorer attention, fine motor coordination, and cognition in the CHAMACOS cohort of school-age children. This study, the largest to date, contributes to growing evidence suggesting that PBDEs have adverse impacts on child neurobehavioral development.Environmental Health Perspectives 11/2012; · 7.04 Impact Factor -
Article: Maternal Urinary Bisphenol A during Pregnancy and Maternal and Neonatal Thyroid Function in the CHAMACOS Study.
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ABSTRACT: Background: Bisphenol A is widely used in the manufacture of polycarbonate plastic bottles, food and beverage cans linings, thermal receipts and dental sealants. Animal and human studies suggest that BPA may disrupt thyroid function. Although thyroid hormones play a determinant role in human growth and brain development, no studies have investigated relations between BPA exposure and thyroid function in pregnant women or neonates. Objectives: To evaluate whether exposure to BPA during pregnancy is related to thyroid hormone levels in pregnant women and neonates. Methods: We measured BPA concentration in urine samples collected during the first and second half of pregnancy in 476 women participating in the CHAMACOS study. We also measured free thyroxine (T4), total T4 and thyroid-stimulating hormone (TSH) during pregnancy, and TSH in neonates. Results: The association between the average of the two BPA measurements and maternal thyroid hormone levels was not statistically significant. Of the two BPA measurements, only the measurement taken closest in time to the TH measurement was significantly associated with a reduction in total T4 (β=-0.13 µg/dL per log2 unit; 95%CI=-0.25, 0.00). The average of the maternal BPA concentrations was associated with reduced TSH in boys (-9.9% per log2 unit; 95%CI=-15.9%, -3.5%) but not in girls. Among boys, the relation was stronger when BPA was measured in the third trimester of pregnancy and decreased with time between BPA and TH measurements. Conclusion: Results suggest that exposure to BPA during pregnancy is related to reduced total T4 in pregnant women and decreased TSH in male neonates. Findings may have implications for fetal and neonatal development.Environmental Health Perspectives 09/2012; · 7.04 Impact Factor -
Article: Cholinesterase and paraoxonase (PON1) enzyme activities in Mexican-American mothers and children from an agricultural community.
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ABSTRACT: Exposure to organophosphate and carbamate pesticides can lead to neurotoxic effects through inhibition of cholinesterase enzymes. The paraoxonase (PON1) enzyme can detoxify oxon derivatives of some organophosphates. Lower PON1, acetylcholinesterase, and butyrylcholinesterase activities have been reported in newborns relative to adults, suggesting increased susceptibility to organophosphate exposure in young children. We determined PON1, acetylcholinesterase, and butyrylcholinesterase activities in Mexican-American mothers and their 9-year-old children (n=202 pairs) living in an agricultural community. We used Wilcoxon signed-rank tests to compare enzymatic activities among mothers and their children, and analysis of variance to identify factors associated with enzyme activities. Substrate-specific PON1 activities were slightly lower in children than their mothers; however, these differences were only statistically significant for the paraoxon substrate. We observed significantly lower acetylcholinesterase but higher butyrylcholinesterase levels in children compared with their mothers. Mean butyrylcholinesterase levels were strongly associated with child obesity status (body mass index Z scores >95%). We observed highly significant correlations among mother-child pairs for each of the enzymatic activities analyzed; however, PON1 activities did not correlate with acetylcholinesterase or butyrylcholinesterase activities. Our findings suggest that by age 9 years, PON1 activities approach adult levels, and host factors including sex and obesity may affect key enzymes involved in pesticide metabolism.Journal of Exposure Science and Environmental Epidemiology 07/2012; 22(6):641-8. · 2.93 Impact Factor -
Article: Prenatal exposure to polybrominated diphenyl ether flame retardants and neonatal thyroid-stimulating hormone levels in the CHAMACOS study.
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ABSTRACT: Studies published in the last 3 decades have demonstrated global human exposure to polybrominated diphenyl ether (PBDE) flame retardants. A growing body of literature suggests that PBDEs may disrupt thyroid hormone homeostasis. Although thyroid hormones play an essential role in brain development, few studies have investigated relations between prenatal exposure to PBDEs and neonatal thyroid hormone levels, and none have measured thyroid-stimulating hormone (TSH) levels in neonates. The authors measured 10 PBDE congeners in serum collected between October 1999 and October 2000 from 289 pregnant women living in California's Salinas Valley and abstracted TSH levels from their children's medical records. Individual PBDE congeners showed null or weak nonsignificant inverse relations with neonatal TSH. Total serum PBDE was not associated with neonatal TSH (β = 0.00, 95% confidence interval: -0.06, 0.06). Except for brominated diphenyl ether 153, a higher serum PBDE level was related to elevated odds of high TSH (≥80th percentile), but associations were not statistically significant. Associations were not modified by infant sex, age at TSH measurement, maternal serum polychlorinated biphenyl concentration, or mode of delivery. Results were robust to sensitivity analysis. The authors found no conclusive evidence that prenatal exposure to PBDEs at levels similar to those of the general US population is related to neonatal TSH.American journal of epidemiology 11/2011; 174(10):1166-74. · 5.59 Impact Factor -
Article: Association of prenatal exposure to polybrominated diphenyl ethers and infant birth weight.
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ABSTRACT: Polybrominated diphenyl ethers (PBDEs) are a class of persistent compounds that have been used as flame retardants in vehicles, household furnishings, and consumer electronics. This study examined whether concentrations of PBDEs in maternal serum during pregnancy were associated with infant birth weight, length, head circumference, and length of gestation. Participants were pregnant women (n = 286) enrolled in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) Study, a longitudinal cohort study of low-income, predominantly Mexican families living in the Salinas Valley, California. Blood samples were collected near the 26th week of pregnancy in 1999-2000, and concentrations of 10 PBDE congeners (BDE-17, -28, -47, -66, -85, -99, -100, -153, -154, and -183) were measured. Multiple linear regression models were used to investigate the association of lipid-adjusted, log(10)-transformed PBDE concentrations and birth outcome. In adjusted analyses, negative associations with birth weight were seen with BDE-47 (β = -115 g, 95% confidence interval (CI): -229, -2), BDE-99 (β = -114 g, 95% CI: -225, -4), and BDE-100 (β = -122 g, 95% CI: -235, -9). These findings were diminished slightly and were no longer statistically significant when maternal weight gain was included in the models. PBDE congeners were not associated with birth length, head circumference, or gestational duration.American journal of epidemiology 08/2011; 174(8):885-92. · 5.59 Impact Factor -
Article: Determinants of serum polybrominated diphenyl ether (PBDE) levels among pregnant women in the CHAMACOS cohort.
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ABSTRACT: We measured levels of 10 polybrominated diphenyl ether (PBDE) congeners in serum collected during pregnancy and at delivery from 416 pregnant, predominantly immigrant, women living in Monterey County, CA. The most frequently detected congeners were BDE-47, -99, -100, and -153, all components of the penta mixture, detected in >97% of samples. We used multivariable regression models to examine factors associated with exposure to individual PBDE congeners as well as their total summed concentration (ng/g lipid). Prenatal and delivery total PBDE levels were correlated between sampling times (n = 21; Pearson r = 0.99, p < 0.001). In multivariable models, total PBDE levels increased significantly with time residing in the U.S. (p < 0.001) and among women with ≥3 pieces of stuffed furniture in their homes (p < 0.05). Women's total PBDE levels increased 4.0% (95% CI = 2.8, 5.3) for each additional year residing in the U.S., after adjustment for prepregnancy BMI, weight gain during pregnancy, and SES. Having ≥3 pieces of stuffed furniture in the home was associated with a 26.8% (95% CI = 2.0, 57.5) increase in women's serum PBDE levels. Findings suggest PBDE indoor contamination in California homes is contributing to human exposures in a population of recent immigrants.Environmental Science & Technology 08/2011; 45(15):6553-60. · 4.80 Impact Factor -
Article: Prenatal exposure to organophosphate pesticides and IQ in 7-year-old children.
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ABSTRACT: Organophosphate (OP) pesticides are neurotoxic at high doses. Few studies have examined whether chronic exposure at lower levels could adversely affect children's cognitive development. We examined associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children. We conducted a birth cohort study (Center for the Health Assessment of Mothers and Children of Salinas study) among predominantly Latino farmworker families from an agricultural community in California. We assessed exposure to OP pesticides by measuring dialkyl phosphate (DAP) metabolites in urine collected during pregnancy and from children at 6 months and 1, 2, 3.5, and 5 years of age. We administered the Wechsler Intelligence Scale for Children, 4th edition, to 329 children 7 years of age. Analyses were adjusted for maternal education and intelligence, Home Observation for Measurement of the Environment score, and language of cognitive assessment. Urinary DAP concentrations measured during the first and second half of pregnancy had similar relations to cognitive scores, so we used the average of concentrations measured during pregnancy in further analyses. Averaged maternal DAP concentrations were associated with poorer scores for Working Memory, Processing Speed, Verbal Comprehension, Perceptual Reasoning, and Full-Scale intelligence quotient (IQ). Children in the highest quintile of maternal DAP concentrations had an average deficit of 7.0 IQ points compared with those in the lowest quintile. However, children's urinary DAP concentrations were not consistently associated with cognitive scores. Prenatal but not postnatal urinary DAP concentrations were associated with poorer intellectual development in 7-year-old children. Maternal urinary DAP concentrations in the present study were higher but nonetheless within the range of levels measured in the general U.S. population.Environmental Health Perspectives 04/2011; 119(8):1189-95. · 7.04 Impact Factor -
Article: Association of organophosphate pesticide exposure and paraoxonase with birth outcome in Mexican-American women.
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ABSTRACT: Epidemiologic studies suggest that maternal organophosphorus (OP) pesticide exposure is associated with poorer fetal growth, but findings are inconsistent. We explored whether paraoxonase (PON1), a key enzyme involved in detoxification of OPs, could be an effect modifier in this association. The study population included 470 pregnant women enrolled in the CHAMACOS Study, a longitudinal cohort study of mothers and children living in an agricultural region of California. We analyzed urine samples collected from mothers twice during pregnancy for dialkyl phosphate (DAP) metabolites of OP pesticides. We analyzed maternal and fetal (cord) blood samples for PON1 genotype (PON1(192) and PON1(-108)) and enzyme activity (paraoxonase and arylesterase). Infant birth weight, head circumference, and gestational age were obtained from medical records. Infants' PON1 genotype and activity were associated with birth outcome, but mothers' were not. Infants with the susceptible PON1(-108TT) genotype had shorter gestational age (β = -0.5 weeks, 95% Confidence Interval (CI): -0.9, 0.0) and smaller head circumference (β = -0.4 cm, 95% CI: -0.7, 0.0) than those with the PON1(-108CC) genotype. Infants' arylesterase and paraoxonase activity were positively associated with gestational age. There was some evidence of effect modification with DAPs: maternal DAP concentrations were associated with shorter gestational age only among infants of the susceptible PON1(-108TT) genotype (p-value(interaction) = 0.09). However, maternal DAP concentrations were associated with larger birth weight (p-value(interaction) = 0.06) and head circumference (p-value(interaction)<0.01) in infants with non-susceptible genotypes. Infants whose PON1 genotype and enzyme activity levels suggested that they might be more susceptible to the effects of OP pesticide exposure had decreased fetal growth and length of gestation. PON1 may be another factor contributing to preterm or low birth weight birth.PLoS ONE 01/2011; 6(8):e23923. · 4.09 Impact Factor -
Article: Maternal Thyroid Function during the Second Half of Pregnancy and Child Neurodevelopment at 6, 12, 24, and 60 Months of Age.
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ABSTRACT: Although evidence suggests that maternal hypothyroidism and mild hypothyroxinemia during the first half of pregnancy alters fetal neurodevelopment among euthyroid offspring, little data are available from later in gestation. In this study, we measured free T4 using direct equilibrium dialysis, as well as total T4 and TSH in 287 pregnant women at 27 weeks' gestation. We also assessed cognition, memory, language, motor functioning, and behavior in their children at 6, 12, 24, and 60 months of age. Increasing maternal TSH was related to better performance on tests of cognition and language at 12 months but not at later ages. At 60 months, there was inconsistent evidence that higher TSH was related to improved attention. We found no convincing evidence that maternal TH during the second half of pregnancy was related to impaired child neurodevelopment.Journal of thyroid research. 01/2011; 2011:426427. -
Article: PON1 and neurodevelopment in children from the CHAMACOS study exposed to organophosphate pesticides in utero.
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ABSTRACT: Paraoxonase 1 (PON1) detoxifies oxon derivatives of some organophosphate (OP) pesticides, and its genetic polymorphisms influence enzyme activity and quantity. We previously reported that maternal urinary concentrations of dialkyl phosphate (DAP) metabolites, a marker of OP pesticide exposure, were related to poorer mental development and maternally reported symptoms consistent with pervasive developmental disorder (PDD) in 2-year-olds participating in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study. We determined whether PON1 genotypes and enzyme measurements were associated with child neurobehavioral development and whether PON1 modified the association of in utero exposure to OPs (as assessed by maternal DAPs) and neurobehavior. We measured DAP concentrations in maternal urine during pregnancy, PON1₁₉₂ and PON1₋₁₀₈ genotypes in mothers and children, and arylesterase (ARYase) and paraoxonase (POase) in maternal, cord, and 2-year-olds' blood. We assessed 353 2-year-olds on the Mental Development Index (MDI) and Psychomotor Development Index (PDI) of the Bayley Scales of Infant Development and queried their mothers on the Child Behavior Checklist to obtain a score for PDD. Children with the PON1(-108T) allele had poorer MDI scores and somewhat poorer PDI scores. Children were less likely to display PDD when they or their mothers had higher ARYase activity and when their mothers had higher POase activity. The association between DAPs and MDI scores was strongest in children with PON1(-108T) allele, but this and other interactions between DAPs and PON1 polymorphisms or enzymes were not significant. PON1 was associated with child neurobehavioral development, but additional research is needed to confirm whether it modifies the relation with in utero OP exposure.Environmental Health Perspectives 12/2010; 118(12):1775-81. · 7.04 Impact Factor -
Article: Polybrominated diphenyl ether (PBDE) flame retardants and thyroid hormone during pregnancy.
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ABSTRACT: Human exposure to polybrominated diphenyl ether (PBDE) flame retardants has increased exponentially over the last three decades. Animal and human studies suggest that PBDEs may disrupt thyroid function. Although thyroid hormone (TH) of maternal origin plays an essential role in normal fetal brain development, there is a paucity of human data regarding associations between exposure to PBDEs and maternal TH levels during pregnancy. Our goal was to determine whether PBDE serum concentrations are associated with TH levels in pregnant women. We measured the concentration of 10 PBDE congeners, free thyroxine (T4), total T4, and thyroid-stimulating hormone (TSH) in 270 pregnant women around the 27th week of gestation. Serum concentrations of individual PBDE congeners with detection frequencies > 50% (BDEs 28, 47, 99, 100, and 153) and their sum (ΣPBDEs) were inversely associated with TSH levels. Decreases in TSH ranged between 10.9% [95% confidence interval (CI), -20.6 to 0.0] and 18.7% (95% CI, -29.2 to -4.5) for every 10-fold increase in the concentration of individual congeners. Odds of subclinical hyperthyroidism (low TSH but normal T4) were also significantly elevated in participants in the highest quartile of ΣPBDEs and BDEs 100 and 153 relative to those in the first quartile. Associations between PBDEs and free and total T4 were not statistically significant. Results were not substantially altered after the removal of outliers and were independent of the method used to adjust for blood lipid levels and to express ΣPBDEs. Results suggest that exposure to PBDEs is associated with lower TSH during pregnancy. Findings may have implications for maternal health and fetal development.Environmental Health Perspectives 10/2010; 118(10):1444-9. · 7.04 Impact Factor -
Article: PBDE Concentrations in Women: Harley et al. Respond.
Environmental Health Perspectives 08/2010; 118(8):a330-1. · 7.04 Impact Factor -
Article: PBDE concentrations in women's serum and fecundability.
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ABSTRACT: Exposure to polybrominated diphenyl ether (PBDE) flame retardants is widespread, with 97% of Americans having detectable levels. Although PBDEs have been associated with reproductive and hormonal effects in animals, no human studies have examined their association with fertility. This study was designed to determine whether maternal concentrations of PBDEs in serum collected during pregnancy are associated with time to pregnancy and menstrual cycle characteristics. Pregnant women (n = 223) living in a low-income, predominantly Mexican-immigrant community in California were interviewed to determine how many months they took to become pregnant. Blood samples were collected and analyzed for PBDEs. PBDE concentrations were lipid adjusted and log10 transformed. Analyses were limited to PBDE congeners detected in > 75% of the population (BDEs 47, 99, 100, 153). Cox proportional hazards models modified for discrete time were used to obtain fecundability odds ratios (fORs) for the association of PBDEs and time to pregnancy. We detected all four congeners in > 97% of women. Increasing levels of BDEs 47, 99, 100, 153 and the sum of these four congeners were all associated with longer time to pregnancy. We observed significantly reduced fORs for BDE-100 [adjusted fOR = 0.6; 95% confidence interval (CI), 0.4-0.9], BDE-153 (adjusted fOR = 0.5; 95% CI, 0.3-0.8), and the sum of the four congeners (adjusted fOR = 0.7; 95% CI, 0.5-1.0). PBDEs were not associated with menstrual cycle characteristics. We found significant decreases in fecundability associated with PBDE exposure in women. Future studies are needed to replicate and confirm this finding.Environmental Health Perspectives 05/2010; 118(5):699-704. · 7.04 Impact Factor -
Article: Serum persistent organic pollutants and duration of lactation among Mexican-American women.
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ABSTRACT: Research suggests that estrogenic endocrine-disrupting chemicals interfere with lactation. (1) to determine if estrogenic persistent organic pollutants (POPs) are associated with shortened lactation duration; (2) to determine whether previous breastfeeding history biases associations. We measured selected organochlorines and polychlorinated biphenyls (p, p'-DDE, p, p'-DDT, o, p'-DDT, beta-hexachlorocyclohexane, hexachlorobenzene, and PCBs 44, 49, 52, 118, 138, 153, and 180) in serum from 366 low-income, Mexican-American pregnant women living in an agricultural region of California and assessed breastfeeding duration by questionnaires. We found no association between DDE, DDT, or estrogenic POPs with shortened lactation duration, but rather associations for two potentially estrogenic POPs with lengthened lactation duration arose (HR [95% CI]: 0.6 [0.4, 0.8] for p, p'-DDE & 0.8 [0.6, 1.0] for PCB 52). Associations between antiestrogenic POPs (PCBs 138 and 180) and shortened lactation duration were attributed to a lactation history bias. Estrogenic POPs were not associated with shortened lactation duration, but may be associated with longer lactation duration.Journal of Environmental and Public Health 01/2010; 2010:861757. -
Article: Fungi and pollen exposure in the first months of life and risk of early childhood wheezing.
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ABSTRACT: Many studies have found that the risk of childhood asthma varies by month of birth, but few have examined ambient aeroallergens as an explanatory factor. A study was undertaken to examine whether birth during seasons of elevated ambient fungal spore or pollen concentrations is associated with risk of early wheezing or blood levels of Th1 and Th2 type cells at 24 months of age. 514 children were enrolled before birth and followed to 24 months of age. Early wheezing was determined from medical records, and Th1 and Th2 type cells were measured in peripheral blood using flow cytometry. Ambient aeroallergen concentrations were measured throughout the study period and discrete seasons of high spore and pollen concentrations were defined. A seasonal pattern was observed, with birth in autumn to winter (the spore season) associated with increased odds of early wheezing (adjusted odds ratio 3.1; 95% confidence interval 1.3 to 7.4). Increasing mean daily concentrations of basidiospores and ascospores in the first 3 months of life were associated with increased odds of wheeze, as were increasing mean daily concentrations of total and specific pollen types. Levels of Th1 cells at age 24 months were positively associated with mean spore concentrations and negatively associated with mean pollen concentrations in the first 3 months of life. Children with higher exposure to spores and pollen in the first 3 months of life are at increased risk of early wheezing. This association is independent of other seasonal factors including ambient levels of particulate matter of aerodynamic diameter <or=2.5 microm and lower respiratory infections.Thorax 03/2009; 64(4):353-8. · 6.84 Impact Factor -
Article: PBDE Flame Retardants and Thyroid Hormones: Chevrier et al. Respond
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2009–2012
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University of California, Berkeley
- School of Public Health
Berkeley, CA, USA
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