title: Lactational exposure to polychlorinated biphenyls, dichlorodiphenyltrichloroethane, and dichlorodiphenyldichloroethylene and infant neurodevelopment: an analysis of the pregnancy, infection, and nutrition babies study.
abstract: BACKGROUND
  Polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) are persistent, bioaccumulative, and toxic pollutants that were broadly used in the United States until the 1970s. Common exposure to PCBs, DDT, and dichlorodiphenyldichloroethylene (DDE), the most stable metabolite of DDT, may influence children's neurodevelopment, but study results are not consistent.
  
  
  OBJECTIVE
  We examined the associations between lactational exposure to PCBs, DDT, and DDE and infant development at 12 months, using data from the Pregnancy, Infection, and Nutrition Babies Study, 2004-2006.
  
  
  METHODS
  We measured PCBs, DDT, and DDE in breast milk at the third month postpartum. Lactational exposure of these chemicals was estimated by the product of chemical concentrations and the duration of breast-feeding. Infant development at 12 months of age was measured by the Mullen Scales of Early Learning (n=231) and the Short Form: Level I (infant) of the MacArthur-Bates Communicative Development Indices (n=218).
  
  
  RESULTS
  No consistent associations were observed between lactational exposure to PCBs, DDT, and DDE through the first 12 months and the measures of infant development. However, DDE was associated with scoring below average on the gross motor scale of the Mullen among males only (adjusted odds ratio=1.9; 95% confidence interval, 1.1-3.3).
  
  
  CONCLUSIONS
  Infant neurodevelopment at 12 months of age was not impaired by PCBs, DDT, and DDE at the concentrations measured here, in combination with benefits from long duration of breast-feeding in this population.
authors.affiliation: Department of Epidemiology, Frank Porter Graham Child Development Institute, University of North Carolina, Chapel Hill, Chapel Hill NC 27599, USA.
authors.forename: I-Jen
authors.initials: IJ
authors.lastname: Pan
authors.forename: Julie L
authors.initials: JL
authors.lastname: Daniels
authors.forename: Barbara D
authors.initials: BD
authors.lastname: Goldman
authors.forename: Amy H
authors.initials: AH
authors.lastname: Herring
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Siega-Riz
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Rogan