The Relationship between Prenatal PCB Exposure and Intelligence (IQ) in 9-Year-Old Children

Details

• Alternative Title:
  Environ Health Perspect
• Personal Author:
  Stewart, Paul W. ; Lonky, Edward ; Reihman, Jacqueline ; Pagano, James ; Gump, Brooks B. ; Darvill, Thomas
• Description:
  Background
  
  Several epidemiologic studies have demonstrated relationships between prenatal exposure to polychlorinated biphenyls (PCBs) and modest cognitive impairments in infancy and early childhood. However, few studies have followed cohorts of exposed children long enough to examine the possible impact of prenatal PCB exposure on psychometric intelligence in later childhood. Of the few studies that have done so, one in the Great Lakes region of the United States reported impaired IQ in children prenatally exposed to PCBs, whereas another found no association.
  
  Objectives
  
  This study was designed to determine whether environmental exposure to PCBs predicts lower IQ in school-age children in the Great Lakes region of the northeastern United States.
  
  Methods
  
  We measured prenatal exposure to PCBs and IQ at 9 years of age in 156 subjects from Oswego, New York. We also measured > 50 potential predictors of intelligence in children, including repeated measures of the home environment [Home Observation for Measurement of the Environment (HOME)], socioeconomic status (SES), parental IQ, alcohol/cigarette use, neonatal risk factors, and nutrition.
  
  Results
  
  For each 1-ng/g (wet weight) increase in PCBs in placental tissue, Full Scale IQ dropped by three points (p = 0.02), and Verbal IQ dropped by four points (p = 0.003). The median PCB level was 1.50 ng/g, with a lower quartile of 1.00 ng/g and an upper quartile of 2.06 ng/g. Moreover, this association was significant after controlling for many potential confounders, including prenatal exposure to methylmercury, dichlorodiphenyldichloroethylene, hexachlorobenzene, and lead.
  
  Conclusions
  
  These results, in combination with similar results obtained from a similar study in the Great Lakes conducted 10 years earlier, indicate that prenatal PCB exposure in the Great Lakes region is associated with lower IQ in children.
  
  
• Subjects:
  Child Confounding Factors (Epidemiology) Dose-Response Relationship, Drug Environmental Exposure Environmental Pollutants Female Humans Intelligence Polychlorinated Biphenyls Pregnancy Prenatal Exposure Delayed Effects Research Risk Factors Social Class

  More +
• Source:
  Environ Health Perspect. 2008; 116(10):1416-1422.
• Document Type:
  Journal Article
• Funding:
  1R1TS000070-01/TS/ATSDR CDC HHS/United States ; 5R01ES009815-08/ES/NIEHS NIH HHS/United States
• Place as Subject:
  Oswego, NY
• Volume:
  116
• Issue:
  10
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:9bc0aae90786fa565105ad082c780f35c3454dcca0fd3b6875d6530fa63c4587
• Download URL:
  https://stacks.cdc.gov/view/cdc/23006/cdc_23006_DS1.pdf
• File Type:
  [PDF - 174.01 KB ]