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Brenda Eskenazi - One of the best experts on this subject based on the ideXlab platform.
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early childhood adversity potentiates the adverse association between prenatal Organophosphate Pesticide exposure and child iq the chamacos cohort
Neurotoxicology, 2016Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda EskenaziAbstract: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.
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Organophosphate Pesticide levels in blood and urine of women and newborns living in an agricultural community
Environmental Research, 2012Co-Authors: Karen Huen, Asa Bradman, Kim G. Harley, Paul Yousefi, Dana B. Barr, Brenda Eskenazi, Nina HollandAbstract:Abstract Organophosphate Pesticides are widely used and recent studies suggest associations of in utero exposures with adverse birth outcomes and neurodevelopment. Few studies have characterized Organophosphate Pesticides in human plasma or established how these levels correlate to urinary measurements. We measured Organophosphate Pesticide metabolites in maternal urine and chlorpyrifos and diazinon in maternal and cord plasma of subjects living in an agricultural area to compare levels in two different biological matrices. We also determined paraoxonase 1 (PON1) genotypes (PON1192 and PON1−108) and PON1 substrate-specific activities in mothers and their newborns to examine whether PON1 may affect Organophosphate Pesticide measurements in blood and urine. Chlorpyrifos levels in plasma ranged from 0–1726 ng/mL and non-zero levels were measured in 70.5% and 87.5% of maternal and cord samples, respectively. Diazinon levels were lower (0–0.5 ng/mL); non-zero levels were found in 33.3% of maternal plasma and 47.3% of cord plasma. Significant associations between Organophosphate Pesticide levels in blood and metabolite levels in urine were limited to models adjusting for PON1 levels. Increased maternal PON1 levels were associated with decreased odds of chlorpyrifos and diazinon detection (odds ratio(OR): 0.56 and 0.75, respectively). Blood Organophosphate Pesticide levels of study participants were similar in mothers and newborns and slightly higher than those reported in other populations. However, compared to their mothers, newborns have much lower quantities of the detoxifying PON1 enzyme suggesting that infants may be especially vulnerable to Organophosphate Pesticide exposures.
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Organophosphate Pesticide exposure and attention in young mexican american children
2010Co-Authors: Amy R Marks, Asa Bradman, Kim G. Harley, Dana B. Barr, Katherine Kogut, Caroline Johnson, Norma Calderon, Brenda EskenaziAbstract:Background: In utero exposure to Organophosphate (OP) Pesticides, well-known neurotoxicants, has been associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by maternal urinary dialkyl phosphate (DAP) metabolites during pregnancy, was associated with attention-related outcomes among Mexican-American children living in the agricultural Salinas Valley and followed to ages 31⁄2 (n=331) and 5 (n=323) years. Methods: Mothers completed the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention subtest to children at 31⁄2 years and the 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 5-year olds’ behavior during testing using the Hillside Behavior Rating Scale (HBRS). Results: Prenatal DAPs were non-significantly associated with maternal report of attention problems and ADHD at age 31⁄2, but were significantly related at age 5 (Attention: β = 0.7; 95% confidence interval (CI), 0.2, 1.2; ADHD:β =1.3; 95% CI, 0.4, 2.1). DAPs were associated with the K-CPT ADHD Confidence Index (OR=5.1; 95% CI, 1.7, 15.7) and non-significantly associated with HBRS ADHD (β = 0.4, 95% CI, -0.04, 0.9). DAPs were also associated with a composite ADHD indicator of the various measures (OR=3.6, 95% CI, 1.2, 11.0). Some outcomes exhibited interaction by sex with associations found only among boys. Conclusions: In utero DAPs were associated adversely with attention in young children as assessed by maternal report, psychometrician observation, and direct assessment. These associations were more robust at 5 than 31⁄2 years and stronger in boys. Page 3 of 27
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Organophosphate Pesticide exposure and neurodevelopment in young mexican american children
Environmental Health Perspectives, 2007Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Caroline Johnson, Amy R Marks, Norma Morga, Nicholas P. JewellAbstract:More than one billion pounds of Pesticides are used annually in the United States, three-quarters of which are used in agriculture (Donaldson et al. 2002). Recent biological monitoring studies indicate that Pesticide exposures are widespread in the U.S. population, including to pregnant women and children [Barr et al. 2004; Berkowitz et al. 2003; Bradman et al. 2005; Centers for Disease Control and Prevention (CDC) 2006; Fenske et al. 2000; Whyatt et al. 2003]. There is evidence that fetuses can be exposed to Pesticides. Pesticides pass through the blood–brain barrier and placenta and have also been found in amniotic fluid (Bradman et al. 2003). In addition, relative to their body size, young children may receive greater exposure than adults, because they eat, drink, and breathe more per unit of body weight (National Research Council 1993). They are closer to the floor and surfaces where Pesticides may settle, and have extensive hand-to-mouth contact (Zartarian et al. 2000). Fetuses and young children may also be more susceptible to potential neurotoxic effects of Pesticides, because their brains are developing rapidly (Rice and Barone 2000). Organophosphates (OPs) and carbamates break down the enzyme acetylcholinesterase (AChE), already lower during pregnancy (Evans et al. 1988), allowing acetylycholine to build up in the neuronal junction. AChE inhibition disrupts cell replication and differentiation, synap-togenesis, and axonogenesis (Bigbee et al. 2000; Lauder and Schambra 1999). It is likely that Pesticides also act through noncholinergic mechanisms involving alterations in expression and function of nuclear transcription factors (Dam et al. 2003). Recent studies have shown that fetuses and young children have lower-than-adult levels of detoxifying enzymes (paraoxonase or chlorpyrifos-oxonase) that deactivate OPs (Furlong et al. 2006; Holland et al. 2006), suggesting that they may be more vulnerable to these exposures. Numerous animal studies have demonstrated that in utero or early exposure to OP Pesticides affect neurodevelopment (Eskenazi et al. 1999). Although acute poisonings can cause neurologic impairment in children (Zwiener and Ginsburg 1988), few studies have assessed neurodevelopment of young children after low-level OP Pesticide exposure (Grandjean et al. 2006; Guillette et al. 1998; Rauh et al. 2006; Ruckart et al. 2004; Young et al. 2005), and even fewer have done so using biomarkers of exposure. In an ecologic study (Guillette et al. 1998), 33 Yaqui Mexican 4- to 5-year-olds living in a valley where OPs, organochlorines (OC), and other Pesticides were used were compared with 17 children living where no Pesticides were used. Exposed children showed lower performance in gross motor, eye–hand coordination, draw-a-person, and delayed recall. In a study of 2-to 12-year-olds living in Mississippi and Ohio where methyl parathion was illegally sprayed in homes, exposed children showed decreased selective attention, delayed verbal memory, poorer motor skills, and behavioral problems; yet the authors deemed the results inconclusive because of inconsistent findings across sites (Ruckart et al. 2004). A recent investigation in 72 6- to 9-year-old Ecuadoreans found that those whose mothers worked in floricul-ture during pregnancy scored lower on the Stanford-Binet Copying Test than unexposed children. Concurrent exposure to OPs, as assessed by the children’s urinary dialkyl phosphate (DAP) metabolite levels, was associated with increased reaction time, but not with other domains of neurobehavior (Grandjean et al. 2006). Recently, Rauh et al. (2006) examined the relationship of maternal blood levels of chlorpyrifos, a diethyl phosphate Pesticide, during pregnancy and performance on the Bayley Scales of Infant Development of 254 inner-city minority children through 3 years of age. Three-year-olds with high prenatal chlorpyrifos showed significantly more delays in psychomo-tor and mental development, and mothers reported more attention problems and symptoms of pervasive developmental problems. In the present study, we investigated neurodevelopment and behavior in a cohort of children from primarily Latino, farmworker families living in the Salinas Valley of California. We previously reported that maternal prenatal DAP urinary metabolite levels in this cohort were significantly higher than for the general U.S. population sampled in the National Health and Nutrition Examination Survey (NHANES) survey (Bradman et al. 2005; CDC 2006). Additionally, we found prenatal DAPs to be associated with shortened gestational duration (Eskenazi et al. 2004) and abnormal neonatal reflexes, but not other clusters, on the Brazelton Neonatal Behavioral Assessment Scale (Young et al. 2005). We now present findings on the relationship of maternal prenatal and child DAP levels with performance on the Bayley Scales through 2 years of age and with maternal reports of behavior on the Child Behavior Checklist (CBCL) at 2 years of age.
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association between in utero Organophosphate Pesticide exposure and abnormal reflexes in neonates
Neurotoxicology, 2005Co-Authors: Jessica G Young, Asa Bradman, Dana B. Barr, Brenda Eskenazi, Clement E. Furlong, Eleanor A Gladstone, Lesley Pedersen, Caroline Johnson, Nina HollandAbstract:The detrimental effects of Organophosphate Pesticide (OP) exposure on neurodevelopment have been shown in animals. The present study aimed to assess the relationship between in utero and early postnatal OP exposure and neonatal neurobehavior in humans, as measured by seven clusters (habituation, orientation, motor performance, range of state, regulation of state, autonomic stability, and reflex) on the Brazelton Neonatal Behavioral Assessment Scale (BNBAS). We assessed 381 infants 3 days old (n = 184). Among the >3 day old infants, increasing average prenatal urinary metabolite levels were associated with both an increase in number of abnormal reflexes (total DAP: adjusted beta = 0.53, 95% CI = 0.23, 0.82; dimethyls: adjusted beta = 0.41, 95% CI = 0.12, 0.69; diethyls: adjusted beta = 0.37, 95% CI = 0.09, 0.64), and the proportion of infants with more than three abnormal reflexes (total DAP: adjusted OR = 4.9, 95% CI = 1.5, 16.1; dimethyls: adjusted OR = 3.2, 95% CI = 1.1, 9.8; diethyls: adjusted OR = 3.4, 95% CI = 1.2, 9.9). No detrimental associations were found between postnatal urinary metabolite levels and any of the BNBAS clusters for infants 3 days old at assessment. Whether neonatal reflex functioning is predictive of neuropsychological functioning as the child matures will continue to be evaluated in this birth cohort.
Asa Bradman - One of the best experts on this subject based on the ideXlab platform.
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reliability and factorial validity of a questionnaire to assess Organophosphate Pesticide exposure to agricultural workers in maule chile
International Journal of Environmental Health Research, 2019Co-Authors: Maria Teresa Munozquezada, Asa Bradman, Boris Lucero, Brittney Baumert, Veronica Iglesias, Maria Pia Munoz, Carlos ConchaAbstract:The aim was to evaluate the reliability and validity of a questionnaire to assess Organophosphate Pesticide (OP) exposure in agricultural workers. We then enrolled a random sample of 114 agricultural workers from the region of Maule, Chile (mean age = 50 years [SD = 12]). An internal consistency analysis (Cronbach's alpha> 0.70) and a Varimax rotational factorial analysis were applied. The instrument had a high reliability to predict likely occupational Pesticide exposures: Cronbach's alpha = 0.95, the Kaiser-Meyer-Olkin (KMO) measure was 0.90 and the Bartell sphericity test = p < 0.001. Four factors explaining 68% of the variance were extracted. The factors identified were as follows: (1) labor conditions during application of OPs; (2) use of personal protective equipment; (3) workplace conditions related to OP exposure and (4) home conditions related to OP exposure. The questionnaire has adequate metric properties to characterize likely OP exposure of agricultural workers and to explore associated working and home conditions.
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early childhood adversity potentiates the adverse association between prenatal Organophosphate Pesticide exposure and child iq the chamacos cohort
Neurotoxicology, 2016Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda EskenaziAbstract: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.
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Organophosphate Pesticide levels in blood and urine of women and newborns living in an agricultural community
Environmental Research, 2012Co-Authors: Karen Huen, Asa Bradman, Kim G. Harley, Paul Yousefi, Dana B. Barr, Brenda Eskenazi, Nina HollandAbstract:Abstract Organophosphate Pesticides are widely used and recent studies suggest associations of in utero exposures with adverse birth outcomes and neurodevelopment. Few studies have characterized Organophosphate Pesticides in human plasma or established how these levels correlate to urinary measurements. We measured Organophosphate Pesticide metabolites in maternal urine and chlorpyrifos and diazinon in maternal and cord plasma of subjects living in an agricultural area to compare levels in two different biological matrices. We also determined paraoxonase 1 (PON1) genotypes (PON1192 and PON1−108) and PON1 substrate-specific activities in mothers and their newborns to examine whether PON1 may affect Organophosphate Pesticide measurements in blood and urine. Chlorpyrifos levels in plasma ranged from 0–1726 ng/mL and non-zero levels were measured in 70.5% and 87.5% of maternal and cord samples, respectively. Diazinon levels were lower (0–0.5 ng/mL); non-zero levels were found in 33.3% of maternal plasma and 47.3% of cord plasma. Significant associations between Organophosphate Pesticide levels in blood and metabolite levels in urine were limited to models adjusting for PON1 levels. Increased maternal PON1 levels were associated with decreased odds of chlorpyrifos and diazinon detection (odds ratio(OR): 0.56 and 0.75, respectively). Blood Organophosphate Pesticide levels of study participants were similar in mothers and newborns and slightly higher than those reported in other populations. However, compared to their mothers, newborns have much lower quantities of the detoxifying PON1 enzyme suggesting that infants may be especially vulnerable to Organophosphate Pesticide exposures.
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Organophosphate Pesticide exposure and attention in young mexican american children
2010Co-Authors: Amy R Marks, Asa Bradman, Kim G. Harley, Dana B. Barr, Katherine Kogut, Caroline Johnson, Norma Calderon, Brenda EskenaziAbstract:Background: In utero exposure to Organophosphate (OP) Pesticides, well-known neurotoxicants, has been associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by maternal urinary dialkyl phosphate (DAP) metabolites during pregnancy, was associated with attention-related outcomes among Mexican-American children living in the agricultural Salinas Valley and followed to ages 31⁄2 (n=331) and 5 (n=323) years. Methods: Mothers completed the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention subtest to children at 31⁄2 years and the 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 5-year olds’ behavior during testing using the Hillside Behavior Rating Scale (HBRS). Results: Prenatal DAPs were non-significantly associated with maternal report of attention problems and ADHD at age 31⁄2, but were significantly related at age 5 (Attention: β = 0.7; 95% confidence interval (CI), 0.2, 1.2; ADHD:β =1.3; 95% CI, 0.4, 2.1). DAPs were associated with the K-CPT ADHD Confidence Index (OR=5.1; 95% CI, 1.7, 15.7) and non-significantly associated with HBRS ADHD (β = 0.4, 95% CI, -0.04, 0.9). DAPs were also associated with a composite ADHD indicator of the various measures (OR=3.6, 95% CI, 1.2, 11.0). Some outcomes exhibited interaction by sex with associations found only among boys. Conclusions: In utero DAPs were associated adversely with attention in young children as assessed by maternal report, psychometrician observation, and direct assessment. These associations were more robust at 5 than 31⁄2 years and stronger in boys. Page 3 of 27
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Organophosphate Pesticide exposure and neurodevelopment in young mexican american children
Environmental Health Perspectives, 2007Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Caroline Johnson, Amy R Marks, Norma Morga, Nicholas P. JewellAbstract:More than one billion pounds of Pesticides are used annually in the United States, three-quarters of which are used in agriculture (Donaldson et al. 2002). Recent biological monitoring studies indicate that Pesticide exposures are widespread in the U.S. population, including to pregnant women and children [Barr et al. 2004; Berkowitz et al. 2003; Bradman et al. 2005; Centers for Disease Control and Prevention (CDC) 2006; Fenske et al. 2000; Whyatt et al. 2003]. There is evidence that fetuses can be exposed to Pesticides. Pesticides pass through the blood–brain barrier and placenta and have also been found in amniotic fluid (Bradman et al. 2003). In addition, relative to their body size, young children may receive greater exposure than adults, because they eat, drink, and breathe more per unit of body weight (National Research Council 1993). They are closer to the floor and surfaces where Pesticides may settle, and have extensive hand-to-mouth contact (Zartarian et al. 2000). Fetuses and young children may also be more susceptible to potential neurotoxic effects of Pesticides, because their brains are developing rapidly (Rice and Barone 2000). Organophosphates (OPs) and carbamates break down the enzyme acetylcholinesterase (AChE), already lower during pregnancy (Evans et al. 1988), allowing acetylycholine to build up in the neuronal junction. AChE inhibition disrupts cell replication and differentiation, synap-togenesis, and axonogenesis (Bigbee et al. 2000; Lauder and Schambra 1999). It is likely that Pesticides also act through noncholinergic mechanisms involving alterations in expression and function of nuclear transcription factors (Dam et al. 2003). Recent studies have shown that fetuses and young children have lower-than-adult levels of detoxifying enzymes (paraoxonase or chlorpyrifos-oxonase) that deactivate OPs (Furlong et al. 2006; Holland et al. 2006), suggesting that they may be more vulnerable to these exposures. Numerous animal studies have demonstrated that in utero or early exposure to OP Pesticides affect neurodevelopment (Eskenazi et al. 1999). Although acute poisonings can cause neurologic impairment in children (Zwiener and Ginsburg 1988), few studies have assessed neurodevelopment of young children after low-level OP Pesticide exposure (Grandjean et al. 2006; Guillette et al. 1998; Rauh et al. 2006; Ruckart et al. 2004; Young et al. 2005), and even fewer have done so using biomarkers of exposure. In an ecologic study (Guillette et al. 1998), 33 Yaqui Mexican 4- to 5-year-olds living in a valley where OPs, organochlorines (OC), and other Pesticides were used were compared with 17 children living where no Pesticides were used. Exposed children showed lower performance in gross motor, eye–hand coordination, draw-a-person, and delayed recall. In a study of 2-to 12-year-olds living in Mississippi and Ohio where methyl parathion was illegally sprayed in homes, exposed children showed decreased selective attention, delayed verbal memory, poorer motor skills, and behavioral problems; yet the authors deemed the results inconclusive because of inconsistent findings across sites (Ruckart et al. 2004). A recent investigation in 72 6- to 9-year-old Ecuadoreans found that those whose mothers worked in floricul-ture during pregnancy scored lower on the Stanford-Binet Copying Test than unexposed children. Concurrent exposure to OPs, as assessed by the children’s urinary dialkyl phosphate (DAP) metabolite levels, was associated with increased reaction time, but not with other domains of neurobehavior (Grandjean et al. 2006). Recently, Rauh et al. (2006) examined the relationship of maternal blood levels of chlorpyrifos, a diethyl phosphate Pesticide, during pregnancy and performance on the Bayley Scales of Infant Development of 254 inner-city minority children through 3 years of age. Three-year-olds with high prenatal chlorpyrifos showed significantly more delays in psychomo-tor and mental development, and mothers reported more attention problems and symptoms of pervasive developmental problems. In the present study, we investigated neurodevelopment and behavior in a cohort of children from primarily Latino, farmworker families living in the Salinas Valley of California. We previously reported that maternal prenatal DAP urinary metabolite levels in this cohort were significantly higher than for the general U.S. population sampled in the National Health and Nutrition Examination Survey (NHANES) survey (Bradman et al. 2005; CDC 2006). Additionally, we found prenatal DAPs to be associated with shortened gestational duration (Eskenazi et al. 2004) and abnormal neonatal reflexes, but not other clusters, on the Brazelton Neonatal Behavioral Assessment Scale (Young et al. 2005). We now present findings on the relationship of maternal prenatal and child DAP levels with performance on the Bayley Scales through 2 years of age and with maternal reports of behavior on the Child Behavior Checklist (CBCL) at 2 years of age.
Dana B. Barr - One of the best experts on this subject based on the ideXlab platform.
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prenatal exposure to the Organophosphate Pesticide chlorpyrifos and childhood tremor
Neurotoxicology, 2015Co-Authors: Virginia Rauh, Dana B. Barr, Wanda Garcia, Robin M Whyatt, Megan K Horton, Elan D LouisAbstract:Background The Organophosphate insecticide chlorpyrifos (CPF), widely used for agricultural purposes, has been linked to neurodevelopmental deficits. Possible motor effects at low to moderate levels of exposure have not been evaluated.
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Organophosphate Pesticide levels in blood and urine of women and newborns living in an agricultural community
Environmental Research, 2012Co-Authors: Karen Huen, Asa Bradman, Kim G. Harley, Paul Yousefi, Dana B. Barr, Brenda Eskenazi, Nina HollandAbstract:Abstract Organophosphate Pesticides are widely used and recent studies suggest associations of in utero exposures with adverse birth outcomes and neurodevelopment. Few studies have characterized Organophosphate Pesticides in human plasma or established how these levels correlate to urinary measurements. We measured Organophosphate Pesticide metabolites in maternal urine and chlorpyrifos and diazinon in maternal and cord plasma of subjects living in an agricultural area to compare levels in two different biological matrices. We also determined paraoxonase 1 (PON1) genotypes (PON1192 and PON1−108) and PON1 substrate-specific activities in mothers and their newborns to examine whether PON1 may affect Organophosphate Pesticide measurements in blood and urine. Chlorpyrifos levels in plasma ranged from 0–1726 ng/mL and non-zero levels were measured in 70.5% and 87.5% of maternal and cord samples, respectively. Diazinon levels were lower (0–0.5 ng/mL); non-zero levels were found in 33.3% of maternal plasma and 47.3% of cord plasma. Significant associations between Organophosphate Pesticide levels in blood and metabolite levels in urine were limited to models adjusting for PON1 levels. Increased maternal PON1 levels were associated with decreased odds of chlorpyrifos and diazinon detection (odds ratio(OR): 0.56 and 0.75, respectively). Blood Organophosphate Pesticide levels of study participants were similar in mothers and newborns and slightly higher than those reported in other populations. However, compared to their mothers, newborns have much lower quantities of the detoxifying PON1 enzyme suggesting that infants may be especially vulnerable to Organophosphate Pesticide exposures.
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Organophosphate Pesticide exposure and attention in young mexican american children
2010Co-Authors: Amy R Marks, Asa Bradman, Kim G. Harley, Dana B. Barr, Katherine Kogut, Caroline Johnson, Norma Calderon, Brenda EskenaziAbstract:Background: In utero exposure to Organophosphate (OP) Pesticides, well-known neurotoxicants, has been associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by maternal urinary dialkyl phosphate (DAP) metabolites during pregnancy, was associated with attention-related outcomes among Mexican-American children living in the agricultural Salinas Valley and followed to ages 31⁄2 (n=331) and 5 (n=323) years. Methods: Mothers completed the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention subtest to children at 31⁄2 years and the 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 5-year olds’ behavior during testing using the Hillside Behavior Rating Scale (HBRS). Results: Prenatal DAPs were non-significantly associated with maternal report of attention problems and ADHD at age 31⁄2, but were significantly related at age 5 (Attention: β = 0.7; 95% confidence interval (CI), 0.2, 1.2; ADHD:β =1.3; 95% CI, 0.4, 2.1). DAPs were associated with the K-CPT ADHD Confidence Index (OR=5.1; 95% CI, 1.7, 15.7) and non-significantly associated with HBRS ADHD (β = 0.4, 95% CI, -0.04, 0.9). DAPs were also associated with a composite ADHD indicator of the various measures (OR=3.6, 95% CI, 1.2, 11.0). Some outcomes exhibited interaction by sex with associations found only among boys. Conclusions: In utero DAPs were associated adversely with attention in young children as assessed by maternal report, psychometrician observation, and direct assessment. These associations were more robust at 5 than 31⁄2 years and stronger in boys. Page 3 of 27
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Organophosphate Pesticide exposure and neurodevelopment in young mexican american children
Environmental Health Perspectives, 2007Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Caroline Johnson, Amy R Marks, Norma Morga, Nicholas P. JewellAbstract:More than one billion pounds of Pesticides are used annually in the United States, three-quarters of which are used in agriculture (Donaldson et al. 2002). Recent biological monitoring studies indicate that Pesticide exposures are widespread in the U.S. population, including to pregnant women and children [Barr et al. 2004; Berkowitz et al. 2003; Bradman et al. 2005; Centers for Disease Control and Prevention (CDC) 2006; Fenske et al. 2000; Whyatt et al. 2003]. There is evidence that fetuses can be exposed to Pesticides. Pesticides pass through the blood–brain barrier and placenta and have also been found in amniotic fluid (Bradman et al. 2003). In addition, relative to their body size, young children may receive greater exposure than adults, because they eat, drink, and breathe more per unit of body weight (National Research Council 1993). They are closer to the floor and surfaces where Pesticides may settle, and have extensive hand-to-mouth contact (Zartarian et al. 2000). Fetuses and young children may also be more susceptible to potential neurotoxic effects of Pesticides, because their brains are developing rapidly (Rice and Barone 2000). Organophosphates (OPs) and carbamates break down the enzyme acetylcholinesterase (AChE), already lower during pregnancy (Evans et al. 1988), allowing acetylycholine to build up in the neuronal junction. AChE inhibition disrupts cell replication and differentiation, synap-togenesis, and axonogenesis (Bigbee et al. 2000; Lauder and Schambra 1999). It is likely that Pesticides also act through noncholinergic mechanisms involving alterations in expression and function of nuclear transcription factors (Dam et al. 2003). Recent studies have shown that fetuses and young children have lower-than-adult levels of detoxifying enzymes (paraoxonase or chlorpyrifos-oxonase) that deactivate OPs (Furlong et al. 2006; Holland et al. 2006), suggesting that they may be more vulnerable to these exposures. Numerous animal studies have demonstrated that in utero or early exposure to OP Pesticides affect neurodevelopment (Eskenazi et al. 1999). Although acute poisonings can cause neurologic impairment in children (Zwiener and Ginsburg 1988), few studies have assessed neurodevelopment of young children after low-level OP Pesticide exposure (Grandjean et al. 2006; Guillette et al. 1998; Rauh et al. 2006; Ruckart et al. 2004; Young et al. 2005), and even fewer have done so using biomarkers of exposure. In an ecologic study (Guillette et al. 1998), 33 Yaqui Mexican 4- to 5-year-olds living in a valley where OPs, organochlorines (OC), and other Pesticides were used were compared with 17 children living where no Pesticides were used. Exposed children showed lower performance in gross motor, eye–hand coordination, draw-a-person, and delayed recall. In a study of 2-to 12-year-olds living in Mississippi and Ohio where methyl parathion was illegally sprayed in homes, exposed children showed decreased selective attention, delayed verbal memory, poorer motor skills, and behavioral problems; yet the authors deemed the results inconclusive because of inconsistent findings across sites (Ruckart et al. 2004). A recent investigation in 72 6- to 9-year-old Ecuadoreans found that those whose mothers worked in floricul-ture during pregnancy scored lower on the Stanford-Binet Copying Test than unexposed children. Concurrent exposure to OPs, as assessed by the children’s urinary dialkyl phosphate (DAP) metabolite levels, was associated with increased reaction time, but not with other domains of neurobehavior (Grandjean et al. 2006). Recently, Rauh et al. (2006) examined the relationship of maternal blood levels of chlorpyrifos, a diethyl phosphate Pesticide, during pregnancy and performance on the Bayley Scales of Infant Development of 254 inner-city minority children through 3 years of age. Three-year-olds with high prenatal chlorpyrifos showed significantly more delays in psychomo-tor and mental development, and mothers reported more attention problems and symptoms of pervasive developmental problems. In the present study, we investigated neurodevelopment and behavior in a cohort of children from primarily Latino, farmworker families living in the Salinas Valley of California. We previously reported that maternal prenatal DAP urinary metabolite levels in this cohort were significantly higher than for the general U.S. population sampled in the National Health and Nutrition Examination Survey (NHANES) survey (Bradman et al. 2005; CDC 2006). Additionally, we found prenatal DAPs to be associated with shortened gestational duration (Eskenazi et al. 2004) and abnormal neonatal reflexes, but not other clusters, on the Brazelton Neonatal Behavioral Assessment Scale (Young et al. 2005). We now present findings on the relationship of maternal prenatal and child DAP levels with performance on the Bayley Scales through 2 years of age and with maternal reports of behavior on the Child Behavior Checklist (CBCL) at 2 years of age.
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association between in utero Organophosphate Pesticide exposure and abnormal reflexes in neonates
Neurotoxicology, 2005Co-Authors: Jessica G Young, Asa Bradman, Dana B. Barr, Brenda Eskenazi, Clement E. Furlong, Eleanor A Gladstone, Lesley Pedersen, Caroline Johnson, Nina HollandAbstract:The detrimental effects of Organophosphate Pesticide (OP) exposure on neurodevelopment have been shown in animals. The present study aimed to assess the relationship between in utero and early postnatal OP exposure and neonatal neurobehavior in humans, as measured by seven clusters (habituation, orientation, motor performance, range of state, regulation of state, autonomic stability, and reflex) on the Brazelton Neonatal Behavioral Assessment Scale (BNBAS). We assessed 381 infants 3 days old (n = 184). Among the >3 day old infants, increasing average prenatal urinary metabolite levels were associated with both an increase in number of abnormal reflexes (total DAP: adjusted beta = 0.53, 95% CI = 0.23, 0.82; dimethyls: adjusted beta = 0.41, 95% CI = 0.12, 0.69; diethyls: adjusted beta = 0.37, 95% CI = 0.09, 0.64), and the proportion of infants with more than three abnormal reflexes (total DAP: adjusted OR = 4.9, 95% CI = 1.5, 16.1; dimethyls: adjusted OR = 3.2, 95% CI = 1.1, 9.8; diethyls: adjusted OR = 3.4, 95% CI = 1.2, 9.9). No detrimental associations were found between postnatal urinary metabolite levels and any of the BNBAS clusters for infants 3 days old at assessment. Whether neonatal reflex functioning is predictive of neuropsychological functioning as the child matures will continue to be evaluated in this birth cohort.
Kim G. Harley - One of the best experts on this subject based on the ideXlab platform.
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early childhood adversity potentiates the adverse association between prenatal Organophosphate Pesticide exposure and child iq the chamacos cohort
Neurotoxicology, 2016Co-Authors: Lauren J Stein, Asa Bradman, Kim G. Harley, Robert B Gunier, Katherine Kogut, Brenda EskenaziAbstract: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.
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Organophosphate Pesticide levels in blood and urine of women and newborns living in an agricultural community
Environmental Research, 2012Co-Authors: Karen Huen, Asa Bradman, Kim G. Harley, Paul Yousefi, Dana B. Barr, Brenda Eskenazi, Nina HollandAbstract:Abstract Organophosphate Pesticides are widely used and recent studies suggest associations of in utero exposures with adverse birth outcomes and neurodevelopment. Few studies have characterized Organophosphate Pesticides in human plasma or established how these levels correlate to urinary measurements. We measured Organophosphate Pesticide metabolites in maternal urine and chlorpyrifos and diazinon in maternal and cord plasma of subjects living in an agricultural area to compare levels in two different biological matrices. We also determined paraoxonase 1 (PON1) genotypes (PON1192 and PON1−108) and PON1 substrate-specific activities in mothers and their newborns to examine whether PON1 may affect Organophosphate Pesticide measurements in blood and urine. Chlorpyrifos levels in plasma ranged from 0–1726 ng/mL and non-zero levels were measured in 70.5% and 87.5% of maternal and cord samples, respectively. Diazinon levels were lower (0–0.5 ng/mL); non-zero levels were found in 33.3% of maternal plasma and 47.3% of cord plasma. Significant associations between Organophosphate Pesticide levels in blood and metabolite levels in urine were limited to models adjusting for PON1 levels. Increased maternal PON1 levels were associated with decreased odds of chlorpyrifos and diazinon detection (odds ratio(OR): 0.56 and 0.75, respectively). Blood Organophosphate Pesticide levels of study participants were similar in mothers and newborns and slightly higher than those reported in other populations. However, compared to their mothers, newborns have much lower quantities of the detoxifying PON1 enzyme suggesting that infants may be especially vulnerable to Organophosphate Pesticide exposures.
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Organophosphate Pesticide exposure and attention in young mexican american children
2010Co-Authors: Amy R Marks, Asa Bradman, Kim G. Harley, Dana B. Barr, Katherine Kogut, Caroline Johnson, Norma Calderon, Brenda EskenaziAbstract:Background: In utero exposure to Organophosphate (OP) Pesticides, well-known neurotoxicants, has been associated with neurobehavioral deficits in children. Objectives: We investigated whether OP exposure, as measured by maternal urinary dialkyl phosphate (DAP) metabolites during pregnancy, was associated with attention-related outcomes among Mexican-American children living in the agricultural Salinas Valley and followed to ages 31⁄2 (n=331) and 5 (n=323) years. Methods: Mothers completed the Child Behavior Checklist (CBCL). We administered the NEPSY-II visual attention subtest to children at 31⁄2 years and the 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 5-year olds’ behavior during testing using the Hillside Behavior Rating Scale (HBRS). Results: Prenatal DAPs were non-significantly associated with maternal report of attention problems and ADHD at age 31⁄2, but were significantly related at age 5 (Attention: β = 0.7; 95% confidence interval (CI), 0.2, 1.2; ADHD:β =1.3; 95% CI, 0.4, 2.1). DAPs were associated with the K-CPT ADHD Confidence Index (OR=5.1; 95% CI, 1.7, 15.7) and non-significantly associated with HBRS ADHD (β = 0.4, 95% CI, -0.04, 0.9). DAPs were also associated with a composite ADHD indicator of the various measures (OR=3.6, 95% CI, 1.2, 11.0). Some outcomes exhibited interaction by sex with associations found only among boys. Conclusions: In utero DAPs were associated adversely with attention in young children as assessed by maternal report, psychometrician observation, and direct assessment. These associations were more robust at 5 than 31⁄2 years and stronger in boys. Page 3 of 27
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Organophosphate Pesticide exposure and neurodevelopment in young mexican american children
Environmental Health Perspectives, 2007Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Caroline Johnson, Amy R Marks, Norma Morga, Nicholas P. JewellAbstract:More than one billion pounds of Pesticides are used annually in the United States, three-quarters of which are used in agriculture (Donaldson et al. 2002). Recent biological monitoring studies indicate that Pesticide exposures are widespread in the U.S. population, including to pregnant women and children [Barr et al. 2004; Berkowitz et al. 2003; Bradman et al. 2005; Centers for Disease Control and Prevention (CDC) 2006; Fenske et al. 2000; Whyatt et al. 2003]. There is evidence that fetuses can be exposed to Pesticides. Pesticides pass through the blood–brain barrier and placenta and have also been found in amniotic fluid (Bradman et al. 2003). In addition, relative to their body size, young children may receive greater exposure than adults, because they eat, drink, and breathe more per unit of body weight (National Research Council 1993). They are closer to the floor and surfaces where Pesticides may settle, and have extensive hand-to-mouth contact (Zartarian et al. 2000). Fetuses and young children may also be more susceptible to potential neurotoxic effects of Pesticides, because their brains are developing rapidly (Rice and Barone 2000). Organophosphates (OPs) and carbamates break down the enzyme acetylcholinesterase (AChE), already lower during pregnancy (Evans et al. 1988), allowing acetylycholine to build up in the neuronal junction. AChE inhibition disrupts cell replication and differentiation, synap-togenesis, and axonogenesis (Bigbee et al. 2000; Lauder and Schambra 1999). It is likely that Pesticides also act through noncholinergic mechanisms involving alterations in expression and function of nuclear transcription factors (Dam et al. 2003). Recent studies have shown that fetuses and young children have lower-than-adult levels of detoxifying enzymes (paraoxonase or chlorpyrifos-oxonase) that deactivate OPs (Furlong et al. 2006; Holland et al. 2006), suggesting that they may be more vulnerable to these exposures. Numerous animal studies have demonstrated that in utero or early exposure to OP Pesticides affect neurodevelopment (Eskenazi et al. 1999). Although acute poisonings can cause neurologic impairment in children (Zwiener and Ginsburg 1988), few studies have assessed neurodevelopment of young children after low-level OP Pesticide exposure (Grandjean et al. 2006; Guillette et al. 1998; Rauh et al. 2006; Ruckart et al. 2004; Young et al. 2005), and even fewer have done so using biomarkers of exposure. In an ecologic study (Guillette et al. 1998), 33 Yaqui Mexican 4- to 5-year-olds living in a valley where OPs, organochlorines (OC), and other Pesticides were used were compared with 17 children living where no Pesticides were used. Exposed children showed lower performance in gross motor, eye–hand coordination, draw-a-person, and delayed recall. In a study of 2-to 12-year-olds living in Mississippi and Ohio where methyl parathion was illegally sprayed in homes, exposed children showed decreased selective attention, delayed verbal memory, poorer motor skills, and behavioral problems; yet the authors deemed the results inconclusive because of inconsistent findings across sites (Ruckart et al. 2004). A recent investigation in 72 6- to 9-year-old Ecuadoreans found that those whose mothers worked in floricul-ture during pregnancy scored lower on the Stanford-Binet Copying Test than unexposed children. Concurrent exposure to OPs, as assessed by the children’s urinary dialkyl phosphate (DAP) metabolite levels, was associated with increased reaction time, but not with other domains of neurobehavior (Grandjean et al. 2006). Recently, Rauh et al. (2006) examined the relationship of maternal blood levels of chlorpyrifos, a diethyl phosphate Pesticide, during pregnancy and performance on the Bayley Scales of Infant Development of 254 inner-city minority children through 3 years of age. Three-year-olds with high prenatal chlorpyrifos showed significantly more delays in psychomo-tor and mental development, and mothers reported more attention problems and symptoms of pervasive developmental problems. In the present study, we investigated neurodevelopment and behavior in a cohort of children from primarily Latino, farmworker families living in the Salinas Valley of California. We previously reported that maternal prenatal DAP urinary metabolite levels in this cohort were significantly higher than for the general U.S. population sampled in the National Health and Nutrition Examination Survey (NHANES) survey (Bradman et al. 2005; CDC 2006). Additionally, we found prenatal DAPs to be associated with shortened gestational duration (Eskenazi et al. 2004) and abnormal neonatal reflexes, but not other clusters, on the Brazelton Neonatal Behavioral Assessment Scale (Young et al. 2005). We now present findings on the relationship of maternal prenatal and child DAP levels with performance on the Bayley Scales through 2 years of age and with maternal reports of behavior on the Child Behavior Checklist (CBCL) at 2 years of age.
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Association of in Utero Organophosphate Pesticide Exposure and Fetal Growth and Length of Gestation in an Agricultural Population
Environmental Health Perspectives, 2004Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Erin Weltzien, Nicholas P. Jewell, Clement E. Furlong, Nina HollandAbstract:Although Pesticide use is widespread, little is known about potential adverse health effects of in utero exposure. We investigated the effects of Organophosphate Pesticide exposure during pregnancy on fetal growth and gestational duration in a cohort of low-income, Latina women living in an agricultural community in the Salinas Valley, California. We measured nonspecific metabolites of Organophosphate Pesticides (dimethyl and diethyl phosphates) and metabolites specific to malathion (malathion dicarboxylic acid), chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridinyl) phosphoro-thioate], and parathion (4-nitrophenol) in maternal urine collected twice during pregnancy. We also measured levels of cholinesterase in whole blood and butyryl cholinesterase in plasma in maternal and umbilical cord blood. We failed to demonstrate an adverse relationship between fetal growth and any measure of in utero Organophosphate Pesticide exposure. In fact, we found increases in body length and head circumference associated with some exposure measures. However, we did find decreases in gestational duration associated with two measures of in utero Pesticide exposure: urinary dimethyl phosphate metabolites [beta(adjusted) = -0.41 weeks per log10 unit increase; 95% confidence interval (CI), -0.75 -- -0.02; p = 0.02], which reflect exposure to dimethyl Organophosphate compounds such as malathion, and umbilical cord cholinesterase (beta(adjusted) = 0.34 weeks per unit increase; 95% CI, 0.13-0.55; p = 0.001). Shortened gestational duration was most clearly related to increasing exposure levels in the latter part of pregnancy. These associations with gestational age may be biologically plausible given that Organophosphate Pesticides depress cholinesterase and acetylcholine stimulates contraction of the uterus. However, despite these observed associations, the rate of preterm delivery in this population (6.4%) was lower than in a U.S. reference population.
Nicholas P. Jewell - One of the best experts on this subject based on the ideXlab platform.
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Organophosphate Pesticide exposure and neurodevelopment in young mexican american children
Environmental Health Perspectives, 2007Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Caroline Johnson, Amy R Marks, Norma Morga, Nicholas P. JewellAbstract:More than one billion pounds of Pesticides are used annually in the United States, three-quarters of which are used in agriculture (Donaldson et al. 2002). Recent biological monitoring studies indicate that Pesticide exposures are widespread in the U.S. population, including to pregnant women and children [Barr et al. 2004; Berkowitz et al. 2003; Bradman et al. 2005; Centers for Disease Control and Prevention (CDC) 2006; Fenske et al. 2000; Whyatt et al. 2003]. There is evidence that fetuses can be exposed to Pesticides. Pesticides pass through the blood–brain barrier and placenta and have also been found in amniotic fluid (Bradman et al. 2003). In addition, relative to their body size, young children may receive greater exposure than adults, because they eat, drink, and breathe more per unit of body weight (National Research Council 1993). They are closer to the floor and surfaces where Pesticides may settle, and have extensive hand-to-mouth contact (Zartarian et al. 2000). Fetuses and young children may also be more susceptible to potential neurotoxic effects of Pesticides, because their brains are developing rapidly (Rice and Barone 2000). Organophosphates (OPs) and carbamates break down the enzyme acetylcholinesterase (AChE), already lower during pregnancy (Evans et al. 1988), allowing acetylycholine to build up in the neuronal junction. AChE inhibition disrupts cell replication and differentiation, synap-togenesis, and axonogenesis (Bigbee et al. 2000; Lauder and Schambra 1999). It is likely that Pesticides also act through noncholinergic mechanisms involving alterations in expression and function of nuclear transcription factors (Dam et al. 2003). Recent studies have shown that fetuses and young children have lower-than-adult levels of detoxifying enzymes (paraoxonase or chlorpyrifos-oxonase) that deactivate OPs (Furlong et al. 2006; Holland et al. 2006), suggesting that they may be more vulnerable to these exposures. Numerous animal studies have demonstrated that in utero or early exposure to OP Pesticides affect neurodevelopment (Eskenazi et al. 1999). Although acute poisonings can cause neurologic impairment in children (Zwiener and Ginsburg 1988), few studies have assessed neurodevelopment of young children after low-level OP Pesticide exposure (Grandjean et al. 2006; Guillette et al. 1998; Rauh et al. 2006; Ruckart et al. 2004; Young et al. 2005), and even fewer have done so using biomarkers of exposure. In an ecologic study (Guillette et al. 1998), 33 Yaqui Mexican 4- to 5-year-olds living in a valley where OPs, organochlorines (OC), and other Pesticides were used were compared with 17 children living where no Pesticides were used. Exposed children showed lower performance in gross motor, eye–hand coordination, draw-a-person, and delayed recall. In a study of 2-to 12-year-olds living in Mississippi and Ohio where methyl parathion was illegally sprayed in homes, exposed children showed decreased selective attention, delayed verbal memory, poorer motor skills, and behavioral problems; yet the authors deemed the results inconclusive because of inconsistent findings across sites (Ruckart et al. 2004). A recent investigation in 72 6- to 9-year-old Ecuadoreans found that those whose mothers worked in floricul-ture during pregnancy scored lower on the Stanford-Binet Copying Test than unexposed children. Concurrent exposure to OPs, as assessed by the children’s urinary dialkyl phosphate (DAP) metabolite levels, was associated with increased reaction time, but not with other domains of neurobehavior (Grandjean et al. 2006). Recently, Rauh et al. (2006) examined the relationship of maternal blood levels of chlorpyrifos, a diethyl phosphate Pesticide, during pregnancy and performance on the Bayley Scales of Infant Development of 254 inner-city minority children through 3 years of age. Three-year-olds with high prenatal chlorpyrifos showed significantly more delays in psychomo-tor and mental development, and mothers reported more attention problems and symptoms of pervasive developmental problems. In the present study, we investigated neurodevelopment and behavior in a cohort of children from primarily Latino, farmworker families living in the Salinas Valley of California. We previously reported that maternal prenatal DAP urinary metabolite levels in this cohort were significantly higher than for the general U.S. population sampled in the National Health and Nutrition Examination Survey (NHANES) survey (Bradman et al. 2005; CDC 2006). Additionally, we found prenatal DAPs to be associated with shortened gestational duration (Eskenazi et al. 2004) and abnormal neonatal reflexes, but not other clusters, on the Brazelton Neonatal Behavioral Assessment Scale (Young et al. 2005). We now present findings on the relationship of maternal prenatal and child DAP levels with performance on the Bayley Scales through 2 years of age and with maternal reports of behavior on the Child Behavior Checklist (CBCL) at 2 years of age.
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Association of in Utero Organophosphate Pesticide Exposure and Fetal Growth and Length of Gestation in an Agricultural Population
Environmental Health Perspectives, 2004Co-Authors: Brenda Eskenazi, Asa Bradman, Kim G. Harley, Dana B. Barr, Erin Weltzien, Nicholas P. Jewell, Clement E. Furlong, Nina HollandAbstract:Although Pesticide use is widespread, little is known about potential adverse health effects of in utero exposure. We investigated the effects of Organophosphate Pesticide exposure during pregnancy on fetal growth and gestational duration in a cohort of low-income, Latina women living in an agricultural community in the Salinas Valley, California. We measured nonspecific metabolites of Organophosphate Pesticides (dimethyl and diethyl phosphates) and metabolites specific to malathion (malathion dicarboxylic acid), chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridinyl) phosphoro-thioate], and parathion (4-nitrophenol) in maternal urine collected twice during pregnancy. We also measured levels of cholinesterase in whole blood and butyryl cholinesterase in plasma in maternal and umbilical cord blood. We failed to demonstrate an adverse relationship between fetal growth and any measure of in utero Organophosphate Pesticide exposure. In fact, we found increases in body length and head circumference associated with some exposure measures. However, we did find decreases in gestational duration associated with two measures of in utero Pesticide exposure: urinary dimethyl phosphate metabolites [beta(adjusted) = -0.41 weeks per log10 unit increase; 95% confidence interval (CI), -0.75 -- -0.02; p = 0.02], which reflect exposure to dimethyl Organophosphate compounds such as malathion, and umbilical cord cholinesterase (beta(adjusted) = 0.34 weeks per unit increase; 95% CI, 0.13-0.55; p = 0.001). Shortened gestational duration was most clearly related to increasing exposure levels in the latter part of pregnancy. These associations with gestational age may be biologically plausible given that Organophosphate Pesticides depress cholinesterase and acetylcholine stimulates contraction of the uterus. However, despite these observed associations, the rate of preterm delivery in this population (6.4%) was lower than in a U.S. reference population.