Daily intake of bisphenol A and potential sources of exposure: 2005-2006 National Health and Nutrition Examination Survey.

Nationally representative data on urinary levels of bisphenol A (BPA) and its metabolites in the United States from the 2005-2006 National Health and Nutrition Examination Survey (NHANES) were used to estimate daily BPA intakes. In addition, NHANES data on potential sources of BPA exposure and personal characteristics were explored for their association with urinary BPA levels. On the basis of 2005-2006 NHANES urinary BPA data and assumptions described in this paper, median daily intake for the overall population is approximately 34 ng/kg-day. Median daily BPA intakes for men are statistically significantly higher than for women; there is a significant decrease in daily BPA intake with increasing age. Gender- and age-specific median intakes differ from the overall population by less than a factor of 2. Although estimates of daily BPA intake have decreased compared with those from the 2003-2004 NHANES, it is premature to draw conclusions regarding trends at this time, as there is no indication that BPA use declined from 2003 to 2006. On the basis of an assessment of urinary BPA and questionnaire data from the 2005-2006 NHANES, consumption of soda, school lunches, and meals prepared outside the home--but not bottled water or canned tuna--was statistically significantly associated with higher urinary BPA.