Probabilistic assessment of aggregate risk for bisphenol A by integrating the currently available environmental data

Abstract

Bisphenol A (BPA) is an endocrine disruptor widely used in the production of polycarbonate plastics and epoxy resins. Exposures to BPA have been associated with reproductive, developmental, and cardiovascular effects. In this study, the CalTOX model was used to assess the aggregate health risks on BPA by integrating the currently available BPA data in various environmental media in Taiwan. Local parameters such as chemical properties, local landscape data, and exposure factors were used as model inputs under the continuous source mode. A reference dose (RfD) of 50 μg/kg-day was adopted in this assessment. Monte Carlo simulation was used to simulate great variability of the environmental data. Our results show that an upper limit of 95 % confidence interval of aggregate exposures for the adults (19–64 years old) was 1.05 μg/kg-day, corresponding to a hazard index (HI) of 0.021. The chemical properties (BPA half-life in surface water), intake rates (fruit, vegetable, and fluid intake), and landscape data (average depth of surface waters and leaf wet density) are critical parameters. Finally, HI value would approach to 1 as BPA concentrations in ambient air, surface water, and sediment was greater than 20 ng/m3, 100 μg/L, and 3.3 mg/kg. The quality of the risk assessment on BPA can be further improved by reduction of uncertainty of the abovementioned critical parameters as well as considering additional BPA exposures from canned and packaged goods.