Bisphenol A (BPA) daily intakes in the United States: Estimates from the 2003-2004 NHANES urinary BPA data

Investigations into human exposure to bisphenol A (BPA) have, for the most part, assessed intake based on food consumption estimates combined with measurements or estimates of BPA in foods. In this study, nationally representative data on urinary levels of BPA in the United States ( US) from the 2003-2004 National Health and Nutrition Examination Survey ( NHANES) were used to estimate daily intake of BPA, assuming steady-state excretion. Distributions of intakes for the US population were determined for (i) all NHANES participants with urinary BPA data; (ii) participants by the following age groups: 6-11 years, 12-19 years, 20-39 years, 40-59 years, and 60+ years; and (iii) participants by gender. On the basis of the NHANES urinary BPA data and the assumptions described in this paper, daily BPA intakes for male participants are statistically significantly higher than for female participants, and there are statistically significant differences in daily BPA intakes according to age groups, with the oldest group having the lowest estimated intakes. Median intake was approximately three orders of magnitude below health-based guidance values of 50 mu g/kg-day.