title: Epidemiologic evidence on the health effects of perfluorooctanoic acid (PFOA).
abstract: OBJECTIVE AND SOURCES: We reviewed the epidemiologic literature for PFOA.
  
  
  RESULTS
  Perfluorooctanoic acid (PFOA) does not occur naturally but is present in the serum of most residents of industrialized countries (U.S. median, 4 ng/mL). Drinking water is the primary route of exposure in some populations, but exposure sources are not well understood. PFOA has been used to manufacture such products as Gore-Tex and Teflon. PFOA does not break down in the environment; the human half-life is estimated at about 3 years. PFOA is not metabolized in the body; it is not lipophilic. PFOA is not directly genotoxic; animal data indicate that it can cause several types of tumors and neonatal death and may have toxic effects on the immune, liver, and endocrine systems. Data on the human health effects of PFOA are sparse. There is relatively consistent evidence of modest positive associations with cholesterol and uric acid, although the magnitude of the cholesterol effect is inconsistent across different exposure levels. There is some but much less consistent evidence of a modest positive correlation with liver enzymes. Most findings come from cross-sectional studies, limiting conclusions. Two occupational cohort studies do not provide consistent evidence for chronic disease; both are limited by sample size and reliance on mortality data. Reproductive data have increased recently but are inconsistent, and any observed adverse effects are modest.
  
  
  CONCLUSIONS
  Epidemiologic evidence remains limited, and to date data are insufficient to draw firm conclusions regarding the role of PFOA for any of the diseases of concern.
authors.affiliation: Rollins School of Public Health, Emory University, Atlanta, Georgia, USA. nsteenl@emory.edu
authors.forename: Kyle
authors.initials: K
authors.lastname: Steenland
authors.forename: Tony
authors.initials: T
authors.lastname: Fletcher
authors.forename: David A
authors.initials: DA
authors.lastname: Savitz
mesh_terms: D002210:Caprylates / Q000737:chemistry / Q000633:toxicity*; D002318:Cardiovascular Diseases / Q000453:epidemiology; D002561:Cerebrovascular Disorders / Q000453:epidemiology; D003920:Diabetes Mellitus / Q000453:epidemiology; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000737:chemistry / Q000633:toxicity*; D062665:Epidemiological Monitoring; D005260:Female; D047109:Fetal Development / Q000187:drug effects; D005466:Fluorocarbons / Q000737:chemistry / Q000633:toxicity*; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D006801:Humans; D007107:Immune System / Q000187:drug effects; D007668:Kidney / Q000187:drug effects; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000187:drug effects; D008297:Male; D012098:Reproduction / Q000187:drug effects; D014527:Uric Acid / Q000378:metabolism
chemical_list: D002210:Caprylates; D004785:Environmental Pollutants; D005466:Fluorocarbons; D012739:Gonadal Steroid Hormones; D014527:Uric Acid; C023036:perfluorooctanoic acid