Derivation of a health-based guidance value for bisphenol A via the weight of evidence approach.

There remains a debate over the health-based guidance value of bisphenol A (BPA) worldwide. Through the weight of evidence approach, this study systematically searched and evaluated the updated BPA toxicological data following the guidelines for evaluating the relevance and reliability of toxicological data developed by the China National Center for Food Safety Risk Assessment. Benchmark dose and no observed adverse effect dose/lowest observed adverse effect level methods were used for dose-relationship analysis. A total of 334 articles were used for evidence integration and included in this hazard assessment of BPA. General toxicity, toxicity to the reproductive system, and neurological (developmental) toxicity were included as possible critical effects in the present assessment. With a point of departure of 2310 μg/kg body weight (BW) based on the decreased round spermatid count in rat seminiferous tubules and the human equivalent dose factor of 0.185 using the constructed physiologically based toxicokinetic model of oral intake of BPA in Chinese population, a human equivalent dose of 427 μg/kg BW was obtained. Applying an overall uncertainty factor of 100, the present assessment established a temporary-tolerable daily intake of 4 μg/kg BW for oral exposure of humans to BPA.