An article published on May 23, 2016 by the news blog Health & Environment illustrates the complex toxicity of endocrine disrupting chemicals (EDCs) in the case of bisphenol A (BPA, CAS 80-05-7) and discusses the resulting difficulty in effectively regulating EDCs. Two new studies published in April 2016 demonstrated low-dose effects of BPA in rats and add to scientific evidence that EDCs act in a non-monotonic dose-response (NMDR) manner (FPF reported). Non-monotonic dose-response curves make it “extremely difficult, if not practically impossible, to predict health risks for certain chemicals,” because it cannot be foreseen that “effects which disappear at one dose would not start showing again at another, lower one.” Due to their NMDR properties, EDCs are proposed to require special regulatory status, similar to other classes of chemicals such as carcinogens, mutagens and reprotoxins (CMRs) and chemicals with persistent, bioaccumulative and toxic properties (PBTs). EDCs, CMRs and PBTs are considered groups of hazardous chemicals for which the risks to health cannot be adequately anticipated or controlled. Therefore, they call for a hazard-based approach to regulation which often leads to market bans or restrictions. Giving EDCs special regulatory status thus presents a challenge to industry, who is largely lobbying against restrictive hazard-based regulatory approaches in favor of exposure-driven risk-based approaches. Finding a regulatory compromise between industry’s demand for a risk-based approach and the environmental imperative for a hazard-based approach will be a challenging task, the article concludes.
Health & Environment (May 23, 2016). “Endocrine disruptors: Why is hazard-based regulation of chemicals such a concern to industry?”