Jacobs Engineering Inc., Boston, Massachusetts, USA.
Jacobs Engineering Inc., Denver, Colorado, USA.
Integr Environ Assess Manag. 2021 Jul;17(4):697-704. doi: 10.1002/ieam.4415. Epub 2021 May 13.
Per- and polyfluoroalkyl substances (PFAS) have been around for decades and have been the subject of laboratory and field research studies for nearly as long. Although attention to PFAS has grown in recent years, many unanswered questions remain. Accordingly, the number of research projects designed to improve our understanding of PFAS toxicity, bioaccumulation, and biomagnification, and to improve our ability to predict the interactions of PFAS mixtures, is also increasing. The growing number of ongoing and future research projects focusing on these chemicals will benefit from lessons learned in previous studies. This perspectives article discusses available approaches to mixture risk assessment with specific focus on application to PFAS mixtures. We discuss ongoing research as well as lessons learned from approaches to handling mixtures of other groups of chemicals. Many of these approaches require some detailed understanding of a manageable number of representative chemicals, yet only limited toxicological data are available for most PFAS. With the limited amount of published data currently available, the need for single-chemical and binary-mixture studies persists. Based on our previous work with single-chemical exposures for understudied PFAS, we explored some of the challenges of trying to design and interpret an aquatic concentration-response experiment for a binary mixture of two commonly detected PFAS: perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonic acid (PFHxS). Based on our findings, we propose that addressing risk from PFAS mixtures will likely require combinations of approaches incorporating findings from traditional whole-organism toxicity studies and novel methods relying on in vitro assays, read-across, or quantitative structure activity relationships. Complicating a limited understanding of PFAS mixture toxicity is that relative concentrations of PFAS mixtures vary across sites and time, even at one site. Thus, reliance on empirical data, such as site-specific toxicity sampling or community structure studies, may be needed to fully understand potential impacts of mixtures. Integr Environ Assess Manag 2021;17:697-704. © 2021 SETAC.
全氟和多氟烷基物质（PFAS）已经存在了几十年，并且近几十年来一直是实验室和现场研究的主题。尽管近年来对 PFAS 的关注度有所提高，但仍有许多未解决的问题。因此，旨在提高我们对 PFAS 毒性、生物累积和生物放大的理解能力，并提高我们预测 PFAS 混合物相互作用能力的研究项目的数量也在增加。越来越多的正在进行和未来的研究项目都集中在这些化学物质上，这些项目将从以前的研究中吸取经验教训。本文讨论了现有的混合物风险评估方法，特别关注应用于 PFAS 混合物的方法。我们讨论了正在进行的研究以及从处理其他化学物质混合物的方法中吸取的经验教训。这些方法中的许多方法都需要对一定数量的有代表性的化学物质有一定程度的了解，但对于大多数 PFAS，只有有限的毒理学数据。由于目前可用的已发表数据有限，因此仍然需要进行单一化学物质和二元混合物研究。基于我们之前对研究较少的 PFAS 进行的单一化学物质暴露的工作，我们探讨了为两种常见检测到的 PFAS（全氟辛烷磺酸（PFOS）和全氟己烷磺酸（PFHxS）的二元混合物设计和解释水生浓度-反应实验所面临的一些挑战。根据我们的发现，我们提出，解决 PFAS 混合物的风险可能需要结合传统的整体生物毒性研究的结果以及依赖于体外测定、外推或定量构效关系的新方法。使对 PFAS 混合物毒性的有限理解复杂化的是，即使在一个地点，PFAS 混合物的相对浓度也会随地点和时间而变化。因此，可能需要依靠现场特定毒性采样或群落结构研究等经验数据来充分了解混合物的潜在影响。《综合环境评估与管理》2021 年；17：697-704。版权所有 2021 SETAC。
