title: Social disparities in exposures to bisphenol A and polyfluoroalkyl chemicals: a cross-sectional study within NHANES 2003-2006.
abstract: BACKGROUND
  Bisphenol A (BPA) and polyfluoroalkyl chemicals (PFCs) are suspected endocrine disrupting compounds known to be ubiquitous in people's bodies. Population disparities in exposure to these chemicals have not been fully characterized.
  
  
  METHODS
  We analyzed data from the 2003-2006 National Health and Nutrition Examination Survey. Using multivariable linear regression we examined the association between urinary concentrations of BPA, serum concentrations of four PFCs, and multiple measures of socioeconomic position (SEP): family income, education, occupation, and food security. We also examined associations with race/ethnicity.
  
  
  RESULTS
  All four PFCs were positively associated with family income, whereas BPA was inversely associated with family income. BPA concentrations were higher in people who reported very low food security and received emergency food assistance than in those who did not. This association was particularly strong in children: 6-11 year-olds whose families received emergency food had BPA levels 54% higher (95% CI, 13 to 112%) than children of families who did not. For BPA and PFCs we saw smaller and less consistent associations with education and occupation. Mexican Americans had the lowest concentrations of any racial/ethnic group of both types of chemicals; for PFCs, Mexican Americans not born in the U.S. had much lower levels than those born in the U.S.
  
  
  CONCLUSIONS
  People with lower incomes had higher body burdens of BPA; the reverse was true for PFCs. Family income with adjustment for family size was the strongest predictor of chemical concentrations among the different measures of SEP we studied. Income, education, occupation, and food security appear to capture different aspects of SEP that may be related to exposure to BPA and PFCs and are not necessarily interchangeable as measures of SEP in environmental epidemiology studies. Differences by race/ethnicity were independent of SEP.
authors.affiliation: Boston University School of Public Health, Department of Environmental Health, 715 Albany Street, Boston, MA 02118, USA. jwebbnelson@gmail.com
authors.forename: Jessica W
authors.initials: JW
authors.lastname: Nelson
authors.forename: Madeleine Kangsen
authors.initials: MK
authors.lastname: Scammell
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Hatch
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Webster
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000473:Alkanes / Q000097:blood; D001559:Benzhydryl Compounds; D002648:Child; D002851:Chromatography, High Pressure Liquid; D003430:Cross-Sectional Studies; D004781:Environmental Exposure; D004785:Environmental Pollutants / Q000097:blood* / Q000652:urine*; D005260:Female; D005466:Fluorocarbons / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009749:Nutrition Surveys; D010636:Phenols / Q000652:urine*; D012959:Socioeconomic Factors; D052616:Solid Phase Extraction; D011795:Surveys and Questionnaires; D053719:Tandem Mass Spectrometry; D014481:United States; D055815:Young Adult; D000098826:Bisphenol A Compounds
chemical_list: D000473:Alkanes; D001559:Benzhydryl Compounds; D004785:Environmental Pollutants; D005466:Fluorocarbons; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds