BACKGROUND Dioxin-like chemicals are a group of ubiquitous environmental toxicants that received intense attention in the last two decades of the 20th century. Through extensive mechanistic research and validation, the global community has agreed upon a regulatory strategy for these chemicals that centers on their common additive activation of a single receptor. Applying these regulations has led to decreased exposure in most populations studied. As dioxin-like chemicals moved out of the limelight, research and media attention has turned to other concerning contaminants, including per- and polyfluoroalkyl substances (PFAS). During the 20th century, PFAS were also being quietly emitted into the environment, but only in the last 20 years have we realized the serious threat they pose to health. There is active debate about how to appropriately classify and regulate the thousands of known PFAS and finding a solution for these "forever chemicals" is of the utmost urgency. OBJECTIVES Here, we compare important features of dioxin-like chemicals and PFAS, including the history, mechanism of action, and effective upstream regulatory strategies, with the objective of gleaning insight from the past to improve strategies for addressing PFAS. DISCUSSION The differences between these two chemical classes means that regulatory strategies for dioxin-like chemicals will not be appropriate for PFAS. PFAS exert toxicity by both receptor-based and nonreceptor-based mechanisms, which complicates mixtures evaluation and stymies efforts to develop inexpensive assays that accurately capture toxicity. Furthermore, dioxin-like chemicals were unwanted byproducts, but PFAS are useful and valuable, which has led to intense resistance against efforts to restrict their production. Nonetheless, useful lessons can be drawn from dioxin-like chemicals and applied to PFAS, including eliminating nonessential production of new PFAS and proactive investment in environmental remediation to address their extraordinarily long environmental persistence. https://doi.org/10.1289/EHP14449.

中文翻译：

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二恶英与 PFAS：科学与政策挑战。


背景 二恶英类化学物质是一组无处不在的环境毒物，在 20 世纪的最后二十年受到了强烈关注。通过广泛的机制研究和验证，国际社会已经就这些化学品的监管策略达成一致，该策略以它们对单个受体的常见添加剂激活为中心。应用这些法规导致大多数研究人群的暴露量减少。随着二恶英类化学品不再受到关注，研究和媒体的注意力已转向其他令人担忧的污染物，包括全氟烷基和多氟烷基物质 （PFAS）。在 20 世纪，PFAS 也被悄悄排放到环境中，但直到最近 20 年，我们才意识到它们对健康构成的严重威胁。关于如何适当分类和监管数千种已知 PFAS 的争论很激烈，为这些“永久化学品”寻找解决方案是当务之急。目的 本文比较了二恶英类化学品和 PFAS 的重要特征，包括历史、作用机制和有效的上游监管策略，目的是从过去收集见解，以改进应对 PFAS 的策略。讨论这两种化学品类别之间的差异意味着二恶英类化学品的监管策略不适用于 PFAS。PFAS 通过基于受体和非受体的机制产生毒性，这使得混合物评估复杂化，并阻碍了开发准确捕获毒性的廉价检测方法的努力。此外，二恶英类化学品是不需要的副产品，但 PFAS 是有用且有价值的，这导致了对限制其生产的努力的强烈抵制。 尽管如此，可以从二恶英类化学品中吸取有用的经验教训并应用于 PFAS，包括消除非必要的新 PFAS 生产，以及积极投资于环境修复，以解决其异常长期的环境持久性问题。https://doi.org/10.1289/EHP14449。