Bisphenol A (BPA) is a known endocrine disruptor that hijacks the normal responses of hormones. Yet, traditional toxicology studies indicate that only very high doses of this chemical affect exposed animals—doses as high as 50 mg/kg/day. For the past decade, scientists have used modern scientific techniques to probe the effects of BPA on numerous endpoints that are not examined in those traditional toxicology studies. Examining these non-traditional endpoints reveal a very different story. Because of increased understanding of the mechanisms by which hormones and chemicals that mimic hormones work, it has recently become clear that endocrine disruptors need to be studied at much lower doses.