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Dana B. Barr - One of the best experts on this subject based on the ideXlab platform.

  • pesticide interactions and risks of sperm chromosomal abnormalities
    International Journal of Hygiene and Environmental Health, 2019
    Co-Authors: Zaida I Figueroa, Dana B. Barr, Heather A Young, John D Meeker, Sunni L Mumford, George M Gray, Melissa J Perry
    Abstract:

    Disentangling the separate and synergistic effects of chemicals poses methodological challenges for accurate exposure assessment and for investigating epidemiologically how chemicals affect reproduction. We investigated combined exposures to ubiquitous contemporary use pesticides, specifically organoPhosphates (OP) and pyrethroids (PYR), and their association with germ cell abnormalities among adult men. Fluorescence in situ hybridization was used to determine disomy in sperm nuclei and urine was analyzed for concentrations of PYR metabolites (3-phenoxybenzoic acid; 3PBA) and OP Dialkyl Phosphate (DAP) metabolites. Incidence rate ratios using Poisson models were estimated for each disomy type by exposure quartile of DAP metabolites and 3PBA, controlling for confounders. The shape of the associations between PYRs, OPs and disomy were frequently nonmonotonic. There were consistent interactions between OP and PYR metabolite concentrations and the risk for sperm abnormalities. Taking both chemicals into account simultaneously resulted in quantitatively different associations than what was reported previously for OPs and PYRs separately, demonstrating the importance of modeling multiple concentrations simultaneously. Methods investigating interactions using Poisson models are needed to better quantify chemical interactions and their effects on count-based health outcomes, the importance of which was shown here for germ cell abnormalities.

  • Urinary organoPhosphate insecticide metabolite concentrations during pregnancy and children's interpersonal, communication, repetitive, and stereotypic behaviors at 8 years of age: The home study.
    Environmental research, 2017
    Co-Authors: Marisa Millenson, Dana B. Barr, Joseph M. Braun, Antonia M. Calafat, Yen-tsung Huang, Aimin Chen, Bruce P. Lanphear, Kimberly Yolton
    Abstract:

    Abstract Background Prenatal exposure to organoPhosphate insecticides may be associated with autism spectrum disorders and related behaviors. This association may be modified by single nucleotide polymorphisms in the paraoxonase ( PON1 ) enzyme. Objective We examined the relationship of prenatal organoPhosphate insecticide biomarkers with reciprocal social, repetitive, and stereotypic behaviors in 8-year old children, and modification of this relationship by child PON1 polymorphisms. Methods Among 224 pregnant women, we quantified concentrations of six nonspecific Dialkyl Phosphate (DAP) metabolites of organoPhosphate insecticides in two urine samples collected at ~16 and ~26 weeks gestation. When children were eight years old, we administered the Social Responsiveness Scale (SRS), a continuous measure of various dimensions of interpersonal behavior, communication, and repetitive/stereotypic behaviors. We estimated the association between a 10-fold increase in the sum of six DAP concentrations (ΣDAP) and SRS scores. We examined whether child PON1 192 and PON1 –108 genotypes modified this association. Results After covariate adjustment, ΣDAP concentrations were not associated with SRS scores [β=–1.2; 95% confidence interval (CI): –4.0, 1.6]. Among children with the PON1 –108TT genotype, ΣDAP concentrations were associated with 2.5-point higher (95% CI: −4.9, 9.8) SRS scores; however, the association was not different from the 1.8-point decrease (95% CI: −5.8, 2.2) among children with PON1 –108CT/CC genotypes (ΣDAP × PON1 –108 p-value =0.54). The association between ΣDAP concentrations and SRS scores was not modified by PON1 192 (ΣDAP × PON1 192 p-value =0.89). Conclusions In this cohort, prenatal urinary DAP concentrations were not associated with children's social behaviors; these associations were not modified by child PON1 genotype.

  • Children’s Health Article Cumulative OrganoPhosphate Pesticide Exposure and Risk Assessment among Pregnant Women Living in an Agricultural Community: A Case Study from the CHAMACOS Cohort
    2013
    Co-Authors: Rosemary Castorina, Asa Bradman, Dana B. Barr, Martha E Harnly, Thomas E Mckone, Brenda Eskenazi
    Abstract:

    Approximately 230,000 kg of organoPhosphate (OP) pesticides are applied annually in California’s Salinas Valley. These activities have raised concerns about exposures to area residents. We collected three spot urine samples from pregnant women (between 1999 and 2001) enrolled in CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas), a longitudinal birth cohort study, and analyzed them for six Dialkyl Phosphate metabolites. We used urine from 446 pregnant women to estimate OP pesticide doses with two deterministic steadystate modeling methods: method 1, which assumed the metabolites were attributable entirely to a single diethyl or dimethyl OP pesticide; and method 2, which adapted U.S. Environmental Protection Agency (U.S. EPA) draft guidelines for cumulative risk assessment to estimate dose from a mixture of OP pesticides that share a common mechanism of toxicity. We used pesticide use reporting data for the Salinas Valley to approximate the mixture to which the women were exposed. Based on average OP pesticide dose estimates that assumed exposure to a single OP pesticide (method 1), between 0 % and 36.1 % of study participants ’ doses failed to attain a margin of exposure (MOE) of 100 relative to the U.S. EPA oral benchmark dose 10 (BMD 10), depending on the assumption made about the parent compound. These BMD 10 values are doses expected t

  • Research | Children’s Health OrganoPhosphate Urinary Metabolite Levels during Pregnancy and after Delivery in Women Living in an Agricultural Community
    2013
    Co-Authors: Asa Bradman, Dana B. Barr, Brenda Eskenazi, Katherine Kogut, Roberto Bravo, Rosemary Castorina, Jonathan Chevrier, Martha E Harnly, Thomas E Mckone
    Abstract:

    Little information has been published about pesticide exposures experienced by pregnant women. We measured six Dialkyl Phosphate (DAP) urinary metabolites of organoPhosphate (OP) pesticides in 600 pregnant, low-income women living in the Salinas Valley, California, an agricultural area. A total of 28 % were employed as farm fieldworkers during pregnancy, and 81 % had at least one household member who worked in agriculture. Samples were collected twice during pregnancy (mean = 13 and 26 weeks ’ gestation, respectively) and just after delivery (mean = 9 days). As in other studies, dimethyldithioPhosphate levels were higher than those of other urinary OP metabolites. Total DAP metabolite levels in samples collected after delivery were higher than in samples collected during pregnancy. Median metabolite levels at the first and second prenatal sampling points and at the postpartum collection were 102.8, 106.8, and 227.2 nmol/L, respectively. Both prenatal and postpartum metabolite levels were higher in these Salinas Valley women than in a sample of women of childbearing age in the general U.S. population (National Health and Nutrition Examination Survey), although the deviation from U.S. reference levels was most pronounced after delivery. Higher DAP metabolite levels in the immediate postpartum period may have implications for estimating dose during pregnancy and for exposure during lactation

  • associations of prenatal exposure to organoPhosphate pesticide metabolites with gestational age and birth weight
    Environmental Health Perspectives, 2012
    Co-Authors: Stephen Rauch, Dana B. Barr, Joseph M. Braun, Antonia M. Calafat, Kimberly Yolton, Jane Khoury, Angela M Montesano, Bruce P. Lanphear
    Abstract:

    Background: Prenatal exposure to organoPhosphate (OP) insecticides, a widely used class of pesticides, may be associated with decreased gestational age and lower birth weight. Single nucleotide polymorphisms in paroxanase (PON1) enzyme genotypes may modify the relationships between OP exposure and perinatal outcomes. Objective: We examined the relationship of prenatal OP insecticide exposure, measured using urinary Dialkyl Phosphate (DAP) metabolite concentrations, with gestational age and birth weight. Methods: We measured the concentrations of six nonspecific DAP metabolites of OP insecticides in two maternal spot urine samples collected in a prospective birth cohort. We performed multivariable regression to examine associations between the sum of six DAP concentrations (ΣDAP) with gestational age and birth weight. We also examined whether these associations differed according to infant PON1192 and PON1–108 genotypes. Results: Among 306 mother–infant dyads, a 10-fold increase in ΣDAP concentrations was associated with a decrease in covariate-adjusted gestational age [–0.5 weeks; 95% confidence interval (CI): –0.8, –0.1] and birth weight (–151 g; CI: –287, –16); the decrements in birth weight were attenuated after adjusting for gestational age. The relationship between ΣDAP concentrations and gestational age was stronger for white (–0.7 weeks; CI: –1.1, –0.3) than for black (–0.1 weeks; 95% CI: –0.9, 0.6) newborns. In contrast, there was a greater decrease in birth weight with increasing urinary ΣDAP concentrations for black (–188 g; CI: –395, 19) than for white (–118 g; CI: –296, 60) newborns. Decrements in birth weight and gestational age associated with ΣDAP concentrations were greatest among infants with PON1192QR and PON–108CT genotypes. Conclusions: Prenatal urinary ΣDAP concentrations were associated with shortened gestation and reduced birth weight in this cohort, but the effects differed by race/ethnicity and PON1192/108 genotypes.

Brenda Eskenazi - One of the best experts on this subject based on the ideXlab platform.

  • early childhood adversity potentiates the adverse association between prenatal organoPhosphate pesticide exposure and child iq the chamacos cohort
    Neurotoxicology, 2016
    Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda Eskenazi
    Abstract:

    Previous studies have observed an adverse association between prenatal exposure to organoPhosphate pesticide (OPs) and child cognition, but few studies consider the potential role of social stressors in modifying this relationship.We seek to explore the potential role of early social adversities in modifying the relationship between OPs and child IQ in an agricultural Mexican American population.Participants from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a prospective longitudinal pre-birth cohort study, include 329 singleton infants and their mothers followed from pregnancy through age 7. Dialkyl Phosphate metabolite concentrations (DAPs), a biomarker of organoPhosphate pesticide exposure, were measured in maternal urine collected twice during pregnancy and averaged. Child cognitive ability was assessed at 7 years using the Wechsler Intelligence Scale for Children - Fourth Edition. Demographic characteristics and adversity information were collected during interviews and home visits at numerous time points from pregnancy until age 7.Among low-income Latina mothers and their children in the Salinas Valley, total adversity and specific domains of adversity including poor learning environment and adverse parent-child relationships were negatively associated with child cognition. Adverse associations between DAP concentrations and IQ were stronger in children experiencing greater adversity; these associations varied by child sex. For example, the association between prenatal OP exposure and Full-Scale IQ is potentiated among boys who experienced high adversity in the learning environment (β=-13.3; p-value <0.01).Greater total and domain-specific adversity modifies negative relationships between prenatal OP exposure and child IQ differently among male and female children. These findings emphasize the need to consider plausible interactive pathways between social adversities and environmental exposures.

  • Research | Children’s Health OrganoPhosphate Pesticide Exposure and Attention in Young Mexican-American Children: The CHAMACOS Study
    2013
    Co-Authors: Amy R Marks, Asa Bradman, Katherine Kogut, Caroline Johnson, Norma Calderon, Kim Harley, Dana Boyd Barr, Brenda Eskenazi
    Abstract:

    associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by urinary Dialkyl Phosphate (DAP) metabolites in pregnant women and their children, was associated with attention-related outcomes among Mexican-American children living in an agricultural region of California. Me t h o d s: Children were assessed at ages 3.5 years (n = 331) and 5 years (n = 323). Mothers com‑ pleted the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention sub‑ test to children at 3.5 years and Conners ’ Kiddie Continuous Performance Test (K-CPT) at 5 years. The K-CPT yielded a standardized attention deficit/hyperactivity disorder (ADHD) Confidence Index score. Psychometricians scored behavior of the 5-year-olds during testing using the Hillside Behavior Rating Scale. Res u l t s: Prenatal DAPs (nanomoles per liter) were nonsignificantly associated with maternal report of attention problems and ADHD at age 3.5 years but were significantly related at age 5 years [CBCL attention problems: β = 0.7 points; 95 % confidence interval (CI), 0.2–1.2; ADHD: β = 1.3; 95 % CI, 0.4–2.1]. Prenatal DAPs were associated with scores on the K-CPT ADHD Confidence Index> 70th percentile [odds ratio (OR) = 5.1; 95 % CI, 1.7–15.7] and with a composite ADH

  • Research | Children’s Health PON1 and Neurodevelopment in Children from the CHAMACOS Study Exposed to OrganoPhosphate Pesticides in Utero
    2013
    Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana Boyd Barr, Karen Huen, Amy Marks, Nina Holl
    Abstract:

    Ba c k g r o u n d: 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. Objective: 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. Met h o d s: 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. Res u l t s: 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. Con c l u s i o n: PON1 was associated with child neurobehavioral development, but additional research is needed to confirm whether it modifies the relation with in utero OP exposure

  • Association of OrganoPhosphate Pesticide Exposure and Paraoxonase with Birth Outcome in Mexican-American Women
    2013
    Co-Authors: Kim G. Harley, Asa Bradman, Dana Boyd Barr, Karen Huen, Raul Aguilar Schall, Nina T. Holl, Brenda Eskenazi
    Abstract:

    Background: 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. Methods: 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 (PON1192 and PON12108) and enzyme activity (paraoxonase and arylesterase). Infant birth weight, head circumference, and gestational age were obtained from medical records. Results: Infants ’ PON1 genotype and activity were associated with birth outcome, but mothers ’ were not. Infants with the susceptible PON1 2108TT genotype had shorter gestational age (b = 20.5 weeks, 95 % Confidence Interval (CI): 20.9, 0.0) and smaller head circumference (b = 20.4 cm, 95 % CI: 20.7, 0.0) than those with the PON12108CC 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 PON12108TT genotype (p-valueinteraction = 0.09). However, maternal DAP concentrations were associated with larger birt

  • Children’s Health Article Cumulative OrganoPhosphate Pesticide Exposure and Risk Assessment among Pregnant Women Living in an Agricultural Community: A Case Study from the CHAMACOS Cohort
    2013
    Co-Authors: Rosemary Castorina, Asa Bradman, Dana B. Barr, Martha E Harnly, Thomas E Mckone, Brenda Eskenazi
    Abstract:

    Approximately 230,000 kg of organoPhosphate (OP) pesticides are applied annually in California’s Salinas Valley. These activities have raised concerns about exposures to area residents. We collected three spot urine samples from pregnant women (between 1999 and 2001) enrolled in CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas), a longitudinal birth cohort study, and analyzed them for six Dialkyl Phosphate metabolites. We used urine from 446 pregnant women to estimate OP pesticide doses with two deterministic steadystate modeling methods: method 1, which assumed the metabolites were attributable entirely to a single diethyl or dimethyl OP pesticide; and method 2, which adapted U.S. Environmental Protection Agency (U.S. EPA) draft guidelines for cumulative risk assessment to estimate dose from a mixture of OP pesticides that share a common mechanism of toxicity. We used pesticide use reporting data for the Salinas Valley to approximate the mixture to which the women were exposed. Based on average OP pesticide dose estimates that assumed exposure to a single OP pesticide (method 1), between 0 % and 36.1 % of study participants ’ doses failed to attain a margin of exposure (MOE) of 100 relative to the U.S. EPA oral benchmark dose 10 (BMD 10), depending on the assumption made about the parent compound. These BMD 10 values are doses expected t

Asa Bradman - One of the best experts on this subject based on the ideXlab platform.

  • early childhood adversity potentiates the adverse association between prenatal organoPhosphate pesticide exposure and child iq the chamacos cohort
    Neurotoxicology, 2016
    Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda Eskenazi
    Abstract:

    Previous studies have observed an adverse association between prenatal exposure to organoPhosphate pesticide (OPs) and child cognition, but few studies consider the potential role of social stressors in modifying this relationship.We seek to explore the potential role of early social adversities in modifying the relationship between OPs and child IQ in an agricultural Mexican American population.Participants from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a prospective longitudinal pre-birth cohort study, include 329 singleton infants and their mothers followed from pregnancy through age 7. Dialkyl Phosphate metabolite concentrations (DAPs), a biomarker of organoPhosphate pesticide exposure, were measured in maternal urine collected twice during pregnancy and averaged. Child cognitive ability was assessed at 7 years using the Wechsler Intelligence Scale for Children - Fourth Edition. Demographic characteristics and adversity information were collected during interviews and home visits at numerous time points from pregnancy until age 7.Among low-income Latina mothers and their children in the Salinas Valley, total adversity and specific domains of adversity including poor learning environment and adverse parent-child relationships were negatively associated with child cognition. Adverse associations between DAP concentrations and IQ were stronger in children experiencing greater adversity; these associations varied by child sex. For example, the association between prenatal OP exposure and Full-Scale IQ is potentiated among boys who experienced high adversity in the learning environment (β=-13.3; p-value <0.01).Greater total and domain-specific adversity modifies negative relationships between prenatal OP exposure and child IQ differently among male and female children. These findings emphasize the need to consider plausible interactive pathways between social adversities and environmental exposures.

  • Research | Children’s Health OrganoPhosphate Pesticide Exposure and Attention in Young Mexican-American Children: The CHAMACOS Study
    2013
    Co-Authors: Amy R Marks, Asa Bradman, Katherine Kogut, Caroline Johnson, Norma Calderon, Kim Harley, Dana Boyd Barr, Brenda Eskenazi
    Abstract:

    associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by urinary Dialkyl Phosphate (DAP) metabolites in pregnant women and their children, was associated with attention-related outcomes among Mexican-American children living in an agricultural region of California. Me t h o d s: Children were assessed at ages 3.5 years (n = 331) and 5 years (n = 323). Mothers com‑ pleted the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention sub‑ test to children at 3.5 years and Conners ’ Kiddie Continuous Performance Test (K-CPT) at 5 years. The K-CPT yielded a standardized attention deficit/hyperactivity disorder (ADHD) Confidence Index score. Psychometricians scored behavior of the 5-year-olds during testing using the Hillside Behavior Rating Scale. Res u l t s: Prenatal DAPs (nanomoles per liter) were nonsignificantly associated with maternal report of attention problems and ADHD at age 3.5 years but were significantly related at age 5 years [CBCL attention problems: β = 0.7 points; 95 % confidence interval (CI), 0.2–1.2; ADHD: β = 1.3; 95 % CI, 0.4–2.1]. Prenatal DAPs were associated with scores on the K-CPT ADHD Confidence Index> 70th percentile [odds ratio (OR) = 5.1; 95 % CI, 1.7–15.7] and with a composite ADH

  • Research | Children’s Health PON1 and Neurodevelopment in Children from the CHAMACOS Study Exposed to OrganoPhosphate Pesticides in Utero
    2013
    Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana Boyd Barr, Karen Huen, Amy Marks, Nina Holl
    Abstract:

    Ba c k g r o u n d: 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. Objective: 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. Met h o d s: 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. Res u l t s: 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. Con c l u s i o n: PON1 was associated with child neurobehavioral development, but additional research is needed to confirm whether it modifies the relation with in utero OP exposure

  • Association of OrganoPhosphate Pesticide Exposure and Paraoxonase with Birth Outcome in Mexican-American Women
    2013
    Co-Authors: Kim G. Harley, Asa Bradman, Dana Boyd Barr, Karen Huen, Raul Aguilar Schall, Nina T. Holl, Brenda Eskenazi
    Abstract:

    Background: 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. Methods: 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 (PON1192 and PON12108) and enzyme activity (paraoxonase and arylesterase). Infant birth weight, head circumference, and gestational age were obtained from medical records. Results: Infants ’ PON1 genotype and activity were associated with birth outcome, but mothers ’ were not. Infants with the susceptible PON1 2108TT genotype had shorter gestational age (b = 20.5 weeks, 95 % Confidence Interval (CI): 20.9, 0.0) and smaller head circumference (b = 20.4 cm, 95 % CI: 20.7, 0.0) than those with the PON12108CC 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 PON12108TT genotype (p-valueinteraction = 0.09). However, maternal DAP concentrations were associated with larger birt

  • Children’s Health Article Cumulative OrganoPhosphate Pesticide Exposure and Risk Assessment among Pregnant Women Living in an Agricultural Community: A Case Study from the CHAMACOS Cohort
    2013
    Co-Authors: Rosemary Castorina, Asa Bradman, Dana B. Barr, Martha E Harnly, Thomas E Mckone, Brenda Eskenazi
    Abstract:

    Approximately 230,000 kg of organoPhosphate (OP) pesticides are applied annually in California’s Salinas Valley. These activities have raised concerns about exposures to area residents. We collected three spot urine samples from pregnant women (between 1999 and 2001) enrolled in CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas), a longitudinal birth cohort study, and analyzed them for six Dialkyl Phosphate metabolites. We used urine from 446 pregnant women to estimate OP pesticide doses with two deterministic steadystate modeling methods: method 1, which assumed the metabolites were attributable entirely to a single diethyl or dimethyl OP pesticide; and method 2, which adapted U.S. Environmental Protection Agency (U.S. EPA) draft guidelines for cumulative risk assessment to estimate dose from a mixture of OP pesticides that share a common mechanism of toxicity. We used pesticide use reporting data for the Salinas Valley to approximate the mixture to which the women were exposed. Based on average OP pesticide dose estimates that assumed exposure to a single OP pesticide (method 1), between 0 % and 36.1 % of study participants ’ doses failed to attain a margin of exposure (MOE) of 100 relative to the U.S. EPA oral benchmark dose 10 (BMD 10), depending on the assumption made about the parent compound. These BMD 10 values are doses expected t

Kim G. Harley - One of the best experts on this subject based on the ideXlab platform.

  • early childhood adversity potentiates the adverse association between prenatal organoPhosphate pesticide exposure and child iq the chamacos cohort
    Neurotoxicology, 2016
    Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda Eskenazi
    Abstract:

    Previous studies have observed an adverse association between prenatal exposure to organoPhosphate pesticide (OPs) and child cognition, but few studies consider the potential role of social stressors in modifying this relationship.We seek to explore the potential role of early social adversities in modifying the relationship between OPs and child IQ in an agricultural Mexican American population.Participants from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a prospective longitudinal pre-birth cohort study, include 329 singleton infants and their mothers followed from pregnancy through age 7. Dialkyl Phosphate metabolite concentrations (DAPs), a biomarker of organoPhosphate pesticide exposure, were measured in maternal urine collected twice during pregnancy and averaged. Child cognitive ability was assessed at 7 years using the Wechsler Intelligence Scale for Children - Fourth Edition. Demographic characteristics and adversity information were collected during interviews and home visits at numerous time points from pregnancy until age 7.Among low-income Latina mothers and their children in the Salinas Valley, total adversity and specific domains of adversity including poor learning environment and adverse parent-child relationships were negatively associated with child cognition. Adverse associations between DAP concentrations and IQ were stronger in children experiencing greater adversity; these associations varied by child sex. For example, the association between prenatal OP exposure and Full-Scale IQ is potentiated among boys who experienced high adversity in the learning environment (β=-13.3; p-value <0.01).Greater total and domain-specific adversity modifies negative relationships between prenatal OP exposure and child IQ differently among male and female children. These findings emphasize the need to consider plausible interactive pathways between social adversities and environmental exposures.

  • Research | Children’s Health PON1 and Neurodevelopment in Children from the CHAMACOS Study Exposed to OrganoPhosphate Pesticides in Utero
    2013
    Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana Boyd Barr, Karen Huen, Amy Marks, Nina Holl
    Abstract:

    Ba c k g r o u n d: 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. Objective: 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. Met h o d s: 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. Res u l t s: 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. Con c l u s i o n: PON1 was associated with child neurobehavioral development, but additional research is needed to confirm whether it modifies the relation with in utero OP exposure

  • Association of OrganoPhosphate Pesticide Exposure and Paraoxonase with Birth Outcome in Mexican-American Women
    2013
    Co-Authors: Kim G. Harley, Asa Bradman, Dana Boyd Barr, Karen Huen, Raul Aguilar Schall, Nina T. Holl, Brenda Eskenazi
    Abstract:

    Background: 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. Methods: 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 (PON1192 and PON12108) and enzyme activity (paraoxonase and arylesterase). Infant birth weight, head circumference, and gestational age were obtained from medical records. Results: Infants ’ PON1 genotype and activity were associated with birth outcome, but mothers ’ were not. Infants with the susceptible PON1 2108TT genotype had shorter gestational age (b = 20.5 weeks, 95 % Confidence Interval (CI): 20.9, 0.0) and smaller head circumference (b = 20.4 cm, 95 % CI: 20.7, 0.0) than those with the PON12108CC 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 PON12108TT genotype (p-valueinteraction = 0.09). However, maternal DAP concentrations were associated with larger birt

  • association of organoPhosphate pesticide exposure and paraoxonase with birth outcome in mexican american women
    PLOS ONE, 2011
    Co-Authors: Kim G. Harley, Asa Bradman, Dana B. Barr, Karen Huen, Raul Aguilar Schall, Nina Holland, Brenda Eskenazi
    Abstract:

    Author(s): Harley, Kim; Huen, Karen; Aguilar Schall, Raul; HOLLAND, Nina; Bradman, Asa; Barr, Dana; Eskenazi, Brenda | Abstract: BACKGROUND: 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. METHODS: 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. RESULTS: 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)l0.01) in infants with non-susceptible genotypes. CONCLUSIONS: 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.

  • prenatal exposure to organoPhosphate pesticides and iq in 7 year old children
    Environmental Health Perspectives, 2011
    Co-Authors: Maryse F Bouchard, Asa Bradman, Kim G. Harley, Katherine Kogut, Caroline Johnson, Norma Calderon, Jonathan Chevrier, Michelle Vedar, Celina Trujillo, Dana B. Barr
    Abstract:

    Context: OrganoPhosphate (OP) pesticides are neurotoxic at high doses. Few studies have examined whether chronic exposure at lower levels could adversely impact children’s cognitive development. Objective: To examine associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children. Methods: We conducted a birth-cohort study (CHAMACOS) 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 age 6 months and 1, 2, 3½ and 5 years. We administered the Wechsler Intelligence Scale for Children-IV to 329 seven-year old children. Analyses were adjusted for maternal education and intelligence, HOME score, and language of cognitive assessment. Results: Urinary DAP concentrations measured during the 1st and 2nd half of pregnancy had similar relations to cognitive scores, thus 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 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. Conclusions: 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.

Katherine Kogut - One of the best experts on this subject based on the ideXlab platform.

  • early childhood adversity potentiates the adverse association between prenatal organoPhosphate pesticide exposure and child iq the chamacos cohort
    Neurotoxicology, 2016
    Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda Eskenazi
    Abstract:

    Previous studies have observed an adverse association between prenatal exposure to organoPhosphate pesticide (OPs) and child cognition, but few studies consider the potential role of social stressors in modifying this relationship.We seek to explore the potential role of early social adversities in modifying the relationship between OPs and child IQ in an agricultural Mexican American population.Participants from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a prospective longitudinal pre-birth cohort study, include 329 singleton infants and their mothers followed from pregnancy through age 7. Dialkyl Phosphate metabolite concentrations (DAPs), a biomarker of organoPhosphate pesticide exposure, were measured in maternal urine collected twice during pregnancy and averaged. Child cognitive ability was assessed at 7 years using the Wechsler Intelligence Scale for Children - Fourth Edition. Demographic characteristics and adversity information were collected during interviews and home visits at numerous time points from pregnancy until age 7.Among low-income Latina mothers and their children in the Salinas Valley, total adversity and specific domains of adversity including poor learning environment and adverse parent-child relationships were negatively associated with child cognition. Adverse associations between DAP concentrations and IQ were stronger in children experiencing greater adversity; these associations varied by child sex. For example, the association between prenatal OP exposure and Full-Scale IQ is potentiated among boys who experienced high adversity in the learning environment (β=-13.3; p-value <0.01).Greater total and domain-specific adversity modifies negative relationships between prenatal OP exposure and child IQ differently among male and female children. These findings emphasize the need to consider plausible interactive pathways between social adversities and environmental exposures.

  • Research | Children’s Health OrganoPhosphate Pesticide Exposure and Attention in Young Mexican-American Children: The CHAMACOS Study
    2013
    Co-Authors: Amy R Marks, Asa Bradman, Katherine Kogut, Caroline Johnson, Norma Calderon, Kim Harley, Dana Boyd Barr, Brenda Eskenazi
    Abstract:

    associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by urinary Dialkyl Phosphate (DAP) metabolites in pregnant women and their children, was associated with attention-related outcomes among Mexican-American children living in an agricultural region of California. Me t h o d s: Children were assessed at ages 3.5 years (n = 331) and 5 years (n = 323). Mothers com‑ pleted the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention sub‑ test to children at 3.5 years and Conners ’ Kiddie Continuous Performance Test (K-CPT) at 5 years. The K-CPT yielded a standardized attention deficit/hyperactivity disorder (ADHD) Confidence Index score. Psychometricians scored behavior of the 5-year-olds during testing using the Hillside Behavior Rating Scale. Res u l t s: Prenatal DAPs (nanomoles per liter) were nonsignificantly associated with maternal report of attention problems and ADHD at age 3.5 years but were significantly related at age 5 years [CBCL attention problems: β = 0.7 points; 95 % confidence interval (CI), 0.2–1.2; ADHD: β = 1.3; 95 % CI, 0.4–2.1]. Prenatal DAPs were associated with scores on the K-CPT ADHD Confidence Index> 70th percentile [odds ratio (OR) = 5.1; 95 % CI, 1.7–15.7] and with a composite ADH

  • Research | Children’s Health OrganoPhosphate Urinary Metabolite Levels during Pregnancy and after Delivery in Women Living in an Agricultural Community
    2013
    Co-Authors: Asa Bradman, Dana B. Barr, Brenda Eskenazi, Katherine Kogut, Roberto Bravo, Rosemary Castorina, Jonathan Chevrier, Martha E Harnly, Thomas E Mckone
    Abstract:

    Little information has been published about pesticide exposures experienced by pregnant women. We measured six Dialkyl Phosphate (DAP) urinary metabolites of organoPhosphate (OP) pesticides in 600 pregnant, low-income women living in the Salinas Valley, California, an agricultural area. A total of 28 % were employed as farm fieldworkers during pregnancy, and 81 % had at least one household member who worked in agriculture. Samples were collected twice during pregnancy (mean = 13 and 26 weeks ’ gestation, respectively) and just after delivery (mean = 9 days). As in other studies, dimethyldithioPhosphate levels were higher than those of other urinary OP metabolites. Total DAP metabolite levels in samples collected after delivery were higher than in samples collected during pregnancy. Median metabolite levels at the first and second prenatal sampling points and at the postpartum collection were 102.8, 106.8, and 227.2 nmol/L, respectively. Both prenatal and postpartum metabolite levels were higher in these Salinas Valley women than in a sample of women of childbearing age in the general U.S. population (National Health and Nutrition Examination Survey), although the deviation from U.S. reference levels was most pronounced after delivery. Higher DAP metabolite levels in the immediate postpartum period may have implications for estimating dose during pregnancy and for exposure during lactation

  • prenatal exposure to organoPhosphate pesticides and iq in 7 year old children
    Environmental Health Perspectives, 2011
    Co-Authors: Maryse F Bouchard, Asa Bradman, Kim G. Harley, Katherine Kogut, Caroline Johnson, Norma Calderon, Jonathan Chevrier, Michelle Vedar, Celina Trujillo, Dana B. Barr
    Abstract:

    Context: OrganoPhosphate (OP) pesticides are neurotoxic at high doses. Few studies have examined whether chronic exposure at lower levels could adversely impact children’s cognitive development. Objective: To examine associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children. Methods: We conducted a birth-cohort study (CHAMACOS) 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 age 6 months and 1, 2, 3½ and 5 years. We administered the Wechsler Intelligence Scale for Children-IV to 329 seven-year old children. Analyses were adjusted for maternal education and intelligence, HOME score, and language of cognitive assessment. Results: Urinary DAP concentrations measured during the 1st and 2nd half of pregnancy had similar relations to cognitive scores, thus 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 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. Conclusions: 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.

  • prenatal exposure to organoPhosphate pesticides and iq in 7 year old children
    Environmental Health Perspectives, 2011
    Co-Authors: Maryse F Bouchard, Asa Bradman, Kim G. Harley, Katherine Kogut, Caroline Johnson, Norma Calderon, Jonathan Chevrier, Michelle Vedar, Celina Trujillo, Dana B. Barr
    Abstract:

    Context: 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. Objective: We examined associations between prenatal and postnatal exposure to OP pesticides and cognitive abilities in school-age children. Methods: 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. Results: 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. Conclusions: 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.