title: Exposure of the U.S. population to bisphenol A and 4-tertiary-octylphenol: 2003-2004.
abstract: BACKGROUND
  Bisphenol A (BPA) and 4-tertiary-octylphenol (tOP) are industrial chemicals used in the manufacture of polycarbonate plastics and epoxy resins (BPA) and nonionic surfactants (tOP). These products are in widespread use in the United States.
  
  
  OBJECTIVE
  We aimed to assess exposure to BPA and tOP in the U.S. general population.
  
  
  METHODS
  We measured the total (free plus conjugated) urinary concentrations of BPA and tOP in 2,517 participants > or = 6 years of age in the 2003-2004 National Health and Nutrition Examination Survey using automated solid-phase extraction coupled to isotope dilution-high-performance liquid chromatography-tandem mass spectrometry.
  
  
  RESULTS
  BPA and tOP were detected in 92.6% and 57.4% of the persons, respectively. Least square geometric mean (LSGM) concentrations of BPA were significantly lower in Mexican Americans than in non-Hispanic blacks (p = 0.006) and non-Hispanic whites (p = 0.007); LSGM concentrations for non-Hispanic blacks and non-Hispanic whites were not statistically different (p = 0.21). Females had statistically higher BPA LSGM concentrations than males (p = 0.043). Children had higher concentrations than adolescents (p < 0.001), who in turn had higher concentrations than adults (p = 0.003). LSGM concentrations were lowest for participants in the high household income category (> $45,000/year).
  
  
  CONCLUSIONS
  Urine concentrations of total BPA differed by race/ethnicity, age, sex, and household income. These first U.S. population representative concentration data for urinary BPA and tOP should help guide public health research priorities, including studies of exposure pathways, potential health effects, and risk assessment.
authors.affiliation: Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA. Acalafat@cdc.gov <Acalafat@cdc.gov>
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Calafat
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Ye
authors.forename: Lee-Yang
authors.initials: LY
authors.lastname: Wong
authors.forename: John A
authors.initials: JA
authors.lastname: Reidy
authors.forename: Larry L
authors.initials: LL
authors.lastname: Needham
mesh_terms: D000293:Adolescent; D000328:Adult; D001559:Benzhydryl Compounds; D002648:Child; D003710:Demography; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000652:urine*; D004968:Estrogens, Non-Steroidal / Q000652:urine; D005260:Female; D006801:Humans; D007182:Income; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D010636:Phenols / Q000652:urine*; D014481:United States; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004785:Environmental Pollutants; D004968:Estrogens, Non-Steroidal; D010636:Phenols; C105260:4-tert-octylphenol; C006780:bisphenol A; D000098826:Bisphenol A Compounds