title: Prenatal exposure to mirex impairs neurodevelopment at age of 4 years.
abstract: BACKGROUND
  Some studies have suggested that certain organochlorine (OC) compounds may impair neurodevelopment in animals and humans. The objective of this study was to investigate the association between prenatal exposure to an OC pesticide, mirex, and cognitive development in children at age of 4 years.
  
  
  METHODS
  A population-based birth cohort in Granada (Spain) recruited between 2000 and 2002 was studied between 2005 and 2006, when the children were 4 years old. Complete data for analyses, including mirex determination in placentas, were gathered on a random sample of 104 children. A standardized version of the McCarthy Scales of Children's Abilities (MSCA) was used to assess children's motor and cognitive abilities. Multivariate analyses were performed to evaluate the relation between MSCA scores and prenatal exposure to mirex, adjusting for potential confounders.
  
  
  RESULTS
  The presence of mirex in placenta was inversely associated with cognitive development at 4 years of age: children with prenatal exposure to mirex (>or=limit of quantification: 26%; median: 1.4 ng/g placenta) showed a decrease of 5.15 points in working memory and of 7.33 points in the quantitative area with respect to children of the same age not prenatally exposed to mirex.
  
  
  CONCLUSIONS
  The deficit found in intellectual function during early childhood suggests that prenatal exposure to mirex may have a significant impact on school performance.
authors.affiliation: Department of Personality, Evaluation and Psychological Treatment, School of Psychology, University of Granada, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Puertas
authors.forename: Maria-Jose
authors.initials: MJ
authors.lastname: Lopez-Espinosa
authors.forename: Francisco
authors.initials: F
authors.lastname: Cruz
authors.forename: Rosa
authors.initials: R
authors.lastname: Ramos
authors.forename: Carmen
authors.initials: C
authors.lastname: Freire
authors.forename: Miguel
authors.initials: M
authors.lastname: Pérez-García
authors.forename: Ana
authors.initials: A
authors.lastname: Abril
authors.forename: Jordi
authors.initials: J
authors.lastname: Julvez
authors.forename: Maite
authors.initials: M
authors.lastname: Salvatierra
authors.forename: Cristina
authors.initials: C
authors.lastname: Campoy
authors.forename: Nicolas
authors.initials: N
authors.lastname: Olea
mesh_terms: D002657:Child Development / Q000187:drug effects*; D002675:Child, Preschool; D015331:Cohort Studies; D002658:Developmental Disabilities / Q000209:etiology*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D008917:Mirex / Q000009:adverse effects* / Q000378:metabolism; D009483:Neuropsychological Tests; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D012044:Regression Analysis; D012189:Retrospective Studies; D018709:Statistics, Nonparametric
chemical_list: D008917:Mirex