title: Perfluoroalkyl chemicals and asthma among children 12-19 years of age: NHANES (1999-2008).
abstract: BACKGROUND
  Perfluoroalkyl chemicals (PFCs) are a family of commonly used industrial chemicals whose persistence and ubiquity in human blood samples has led to concern about possible toxicity. Several animal studies and one recent human study have suggested a link between exposure to PFCs and asthma, although few epidemiologic studies have been conducted.
  
  
  OBJECTIVE
  We investigated children's PFC serum concentrations and their associations with asthma-related outcomes.
  
  
  METHODS
  We evaluated the association between serum concentrations of eight PFCs, including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS), with self-reported lifetime asthma, recent wheezing, and current asthma using data from participants 12-19 years of age from the 1999-2000 and 2003-2008 National Health and Nutrition Examination Surveys.
  
  
  RESULTS
  In multivariable-adjusted models, PFOA was associated with higher odds of ever having received a diagnosis of asthma [odds ratio (OR) = 1.18; 95% CI: 1.01, 1.39 for a doubling in PFOA], whereas for PFOS there were inverse relationships with both asthma and wheezing (OR = 0.88; 95% CI: 0.74, 1.04, and OR = 0.83; 95% CI: 0.67, 1.02, respectively). The associations were attenuated after accounting for sampling weights. No associations were seen between the other PFCs and any outcome.
  
  
  CONCLUSIONS
  This cross-sectional study provides some evidence for associations between exposure to PFCs and asthma-related outcomes in children. The evidence is inconsistent, however, and prospective studies are needed.
authors.affiliation: Robert Wood Johnson Foundation Health and Society Scholars Program, Department of Psychiatry, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Olivier
authors.initials: O
authors.lastname: Humblet
authors.forename: Ledif Grisell
authors.initials: LG
authors.lastname: Diaz-Ramirez
authors.forename: John R
authors.initials: JR
authors.lastname: Balmes
authors.forename: Susan M
authors.initials: SM
authors.lastname: Pinney
authors.forename: Robert A
authors.initials: RA
authors.lastname: Hiatt
mesh_terms: D000293:Adolescent; D017738:Alkanesulfonic Acids / Q000097:blood*; D001249:Asthma / Q000097:blood / Q000453:epidemiology*; D002210:Caprylates / Q000097:blood; D002648:Child; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000097:blood*; D005260:Female; D005466:Fluorocarbons / Q000097:blood*; D006306:Health Surveys; D006801:Humans; D008297:Male; D009749:Nutrition Surveys; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D017738:Alkanesulfonic Acids; D002210:Caprylates; D004785:Environmental Pollutants; D005466:Fluorocarbons