Integrated Toxicology and Environmental Health Program, Duke University, Durham, North Carolina, USA.
Nicholas School of the Environment, Duke University, Durham, North Carolina, USA.
Environ Health Perspect. 2024 Aug;132(8):85003. doi: 10.1289/EHP14449. Epub 2024 Aug 12.
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.
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.
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.
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广泛关注。通过广泛的机制研究和验证，全球社会就这些化学物质的监管策略达成一致，该策略集中于它们对单一受体的共同加性激活。应用这些法规导致大多数研究人群的暴露减少。随着二恶英类化学物质不再成为焦点，研究和媒体的注意力转向了其他令人关注的污染物，包括全氟和多氟烷基物质（PFAS）。在 20 世纪，PFAS 也在悄悄地排放到环境中，但直到过去 20 年，我们才意识到它们对健康构成的严重威胁。人们就如何恰当地对数千种已知的 PFAS 进行分类和监管展开了激烈的辩论，为这些“永久化学物质”找到解决方案迫在眉睫。
在这里，我们比较了二恶英类化学物质和 PFAS 的重要特征，包括历史、作用机制和有效的上游监管策略，以期从过去的经验中汲取教训，改进解决 PFAS 问题的策略。
这两类化学物质之间的差异意味着二恶英类化学物质的监管策略不适用于 PFAS。PFAS 通过受体和非受体机制发挥毒性，这使得混合物评估变得复杂，并阻碍了开发能够准确捕捉毒性的廉价检测方法的努力。此外，二恶英类化学物质是不受欢迎的副产品，但 PFAS 是有用且有价值的，这导致了强烈抵制限制其生产的努力。尽管如此，仍可以从二恶英类化学物质中吸取有用的教训并应用于 PFAS，包括消除新 PFAS 的非必要生产以及积极投资于环境修复以解决其极其长的环境持久性。https://doi.org/10.1289/EHP14449.
