title: Environmental chemicals in pregnant women in the United States: NHANES 2003-2004.
abstract: BACKGROUND
  Exposure to chemicals during fetal development can increase the risk of adverse health effects, and while biomonitoring studies suggest pregnant women are exposed to chemicals, little is known about the extent of multiple chemicals exposures among pregnant women in the United States.
  
  
  OBJECTIVE
  We analyzed biomonitoring data from the National Health and Nutritional Examination Survey (NHANES) to characterize both individual and multiple chemical exposures in U.S. pregnant women.
  
  
  METHODS
  We analyzed data for 163 chemical analytes in 12 chemical classes for subsamples of 268 pregnant women from NHANES 2003-2004, a nationally representative sample of the U.S. population. For each chemical analyte, we calculated descriptive statistics. We calculated the number of chemicals detected within the following chemical classes: polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs), organochlorine pesticides, and phthalates and across multiple chemical classes. We compared chemical analyte concentrations for pregnant and nonpregnant women using least-squares geometric means, adjusting for demographic and physiological covariates.
  
  
  RESULTS
  The percentage of pregnant women with detectable levels of an individual chemical ranged from 0 to 100%. Certain polychlorinated biphenyls, organochlorine pesticides, PFCs, phenols, PBDEs, phthalates, polycyclic aromatic hydrocarbons, and perchlorate were detected in 99-100% of pregnant women. The median number of detected chemicals by chemical class ranged from 4 of 12 PFCs to 9 of 13 phthalates. Across chemical classes, median number ranged from 8 of 17 chemical analytes to 50 of 71 chemical analytes. We found, generally, that levels in pregnant women were similar to or lower than levels in nonpregnant women; adjustment for covariates tended to increase levels in pregnant women compared with nonpregnant women.
  
  
  CONCLUSIONS
  Pregnant women in the U.S. are exposed to multiple chemicals. Further efforts are warranted to understand sources of exposure and implications for policy making.
authors.affiliation: Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, Oakland, California 94612, USA. woodrufft@obgyn.ucsf.edu
authors.forename: Tracey J
authors.initials: TJ
authors.lastname: Woodruff
authors.forename: Ami R
authors.initials: AR
authors.lastname: Zota
authors.forename: Jackie M
authors.initials: JM
authors.lastname: Schwartz
mesh_terms: D000293:Adolescent; D000328:Adult; D004781:Environmental Exposure; D004785:Environmental Pollutants / Q000032:analysis* / Q000145:classification*; D005260:Female; D006306:Health Surveys; D006801:Humans; D011247:Pregnancy; D014481:United States; D055815:Young Adult
chemical_list: D004785:Environmental Pollutants