title: Exposure to polyfluoroalkyl chemicals and attention deficit/hyperactivity disorder in U.S. children 12-15 years of age.
abstract: BACKGROUND
  Polyfluoroalkyl chemicals (PFCs) have been widely used in consumer products. Exposures in the United States and in world populations are widespread. PFC exposures have been linked to various health impacts, and data in animals suggest that PFCs may be potential developmental neurotoxicants.
  
  
  OBJECTIVE
  We evaluated the associations between exposures to four PFCs and parental report of diagnosis of attention deficit/hyperactivity disorder (ADHD).
  
  
  METHODS
  Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 1999-2000 and 2003-2004 for children 12-15 years of age. Parental report of a previous diagnosis by a doctor or health care professional of ADHD in the child was the primary outcome measure. Perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS) levels were measured in serum samples from each child.
  
  
  RESULTS
  Parents reported that 48 of 571 children included in the analysis had been diagnosed with ADHD. The adjusted odds ratio (OR) for parentally reported ADHD in association with a 1-μg/L increase in serum PFOS (modeled as a continuous predictor) was 1.03 [95% confidence interval (CI), 1.01-1.05]. Adjusted ORs for 1-μg/L increases in PFOA and PFHxS were also statistically significant (PFOA: OR = 1.12; 95% CI, 1.01-1.23; PFHxS: OR = 1.06; 95% CI, 1.02-1.11), and we observed a nonsignificant positive association with PFNA (OR = 1.32; 95% CI, 0.86-2.02).
  
  
  CONCLUSIONS
  Our results, using cross-sectional data, are consistent with increased odds of ADHD in children with higher serum PFC levels. Given the extremely prevalent exposure to PFCs, follow-up of these data with cohort studies is needed.
authors.affiliation: Department of Environmental Health, Boston University School of Public Health, Boston, Massachusetts, USA. hoffmank@bu.edu
authors.forename: Kate
authors.initials: K
authors.lastname: Hoffman
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Webster
authors.forename: Marc G
authors.initials: MG
authors.lastname: Weisskopf
authors.forename: Janice
authors.initials: J
authors.lastname: Weinberg
authors.forename: Verónica M
authors.initials: VM
authors.lastname: Vieira
mesh_terms: D000293:Adolescent; D017738:Alkanesulfonic Acids / Q000097:blood; D001289:Attention Deficit Disorder with Hyperactivity / Q000097:blood / Q000453:epidemiology*; D002210:Caprylates / Q000097:blood; D002648:Child; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000032:analysis / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000097:blood*; D005260:Female; D005466:Fluorocarbons / Q000097:blood*; D006801:Humans; D008297:Male; D009749:Nutrition Surveys; D013451:Sulfonic Acids / Q000097:blood; D014481:United States / Q000453:epidemiology
chemical_list: D017738:Alkanesulfonic Acids; D002210:Caprylates; D004785:Environmental Pollutants; D005466:Fluorocarbons; D013451:Sulfonic Acids; C471071:perfluorohexanesulfonic acid; C023036:perfluorooctanoic acid; C076994:perfluorooctane sulfonic acid