Effect of Rinsing Canned Foods on Bisphenol-A Exposure: The Hummus Experiment

Bisphenol-A (BPA) is associated with adverse health outcomes and is found in many canned foods. It is not understood if some BPA contamination can be washed away by rinsing. The objective of this single-blinded crossover experiment was to determine whether BPA exposure, as measured by urinary concentrations, could be decreased by rinsing canned beans prior to consumption. Three types of hummus were prepared from dried beans, rinsed, and unrinsed canned beans. Fourteen healthy participants ate two samples of each hummus over six experimental days and collected spot urine specimens for BPA measurement. The geometric mean BPA levels for dried beans BPA (GM = 0.97 ng/ml, 95%CI = 0.74,1.26) was significantly lower than rinsed (GM = 1.89 ng/ml, 1.37,2.59) and unrinsed (GM = 2.46 ng/ml, 1.44,4.19). Difference-in-difference estimates showed an increase in GM BPA from pre- to post-hummus between unrinsed and rinsed canned beans of 1.39 ng/ml, p-value = 0.0400. Rinsing canned beans was an effective method to reduce BPA exposure.