Minority Health and Health Equity Archive

Permanent URI for this collectionhttp://hdl.handle.net/1903/21769

Welcome to the Minority Health and Health Equity Archive (MHHEA), an electronic archive for digital resource materials in the fields of minority health and health disparities research and policy. It is offered as a no-charge resource to the public, academic scholars and health science researchers interested in the elimination of racial and ethnic health disparities.

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Author: search.filters.author.Boyd Barr, DanaSubject: search.filters.subject.Health Risk Factors

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    Prenatal Exposure to Organophosphates, Paraoxonase 1, and Cognitive Development in Childhood
    (2011) Engel, Stephanie M.; Wetmur, James; Chen, Jia; Zhu, Chenbo; Boyd Barr, Dana; Canfield, Richard L.; Wolff, Mary S.
    Background: Prenatal exposure to organophosphate pesticides has been shown to negatively impact child neurobehavioral development. Paraoxonase 1 (PON1) is a key enzyme in the metabolism of organophosphates. Objective: To examine the relationship between biomarkers of organophosphate exposure, PON1, and cognitive development at ages 12 and 24 months, and 6 to 9 years. Methods: The Mount Sinai Children’s Environmental Health Study enrolled a multiethnic prenatal population in New York City between 1998 and 2002 (n= 404). Third trimester maternal urines were collected and analyzed for organophosphate metabolites (n = 360). Prenatal maternal blood was analyzed for PON1 activity and genotype. Children returned for neurodevelopment assessments at ages 12 months (n = 200), 24 months (n = 276), 6 to 9 (n = 169) years. Results: Prenatal total dialkylphosphate metabolite level was associated with a decrement in mental development at 12 months among blacks and Hispanics. These associations appeared to be enhanced among children of mothers who carried the PON1 Q192R QQ genotype, which imparts slow catalytic activity for chlorpyrifos oxon. In later childhood, increasing prenatal total dialkyl- and dimethylphosphate metabolites were associated with decrements in perceptual reasoning in the maternal PON1 Q192R QQ genotype, with a monotonic trend consistent with greater decrements with increasing prenatal exposure. Conclusion: Our findings suggest that prenatal exposure to organophosphates negatively impacts cognitive development, particularly perceptual reasoning, with evidence of effects beginning at 12 months and continuing through early childhood. PON1 may be an important susceptibility factor for these deleterious effects.
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    Prenatal Exposure to Organophosphate Pesticides and IQ in 7-Year Old Children
    (2011) Bouchard, Maryse F.; Chevrier, Jonathan; Harley, Kim G.; Kogut, Katherine; Vedar, Michelle; Calderon, Norma; Trujillo, Celina; Johnson, Caroline; Bradman, Asa; Boyd Barr, Dana; Eskenazi, Brenda
    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.