Oak Ridge Institute for Science and Education, Oak Ridge, TN, 37831, USA; Center for Environmental Measurement and Modeling, Office of Research and Development, U.S. Environmental Protection Agency, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA.
Oak Ridge Institute for Science and Education, Oak Ridge, TN, 37831, USA.
Chemosphere. 2022 Dec;308(Pt 1):136159. doi: 10.1016/j.chemosphere.2022.136159. Epub 2022 Sep 2.
The shift away from PFOS and PFOA production in the past 20 years towards shorter chain and replacement PFAS has led to the environmental release of complex mixtures of emerging PFAS for which bioaccumulation potential and toxicology are largely unknown. The rate at which emerging PFAS can be prioritized for research in these complex mixtures is often limited by the lack of available chemical standards. We developed a study design that rapidly assesses which emerging PFAS in an environmentally derived mixture have the potential for mammalian bioaccumulation and thus prioritize these emerging chemicals for standard synthesis and toxicity testing. Surface water was collected at an impacted site downstream of an industrial fluorochemical manufacturing outfall and concentrated 100-fold via weak anion exchange, solid-phase extraction. The concentrated extract contained 13 previously identified emerging PFAS, including hexafluoropropylene oxide-dimer acid (HFPO-DA). BALB/c mice were orally dosed with surface water concentrate once a day for seven days. Twenty-four hours after the last dose, liver, serum, urine, and feces were collected and the emerging PFAS were semi-quantified based on peak area counts. Of the 13 emerging PFAS, Nafion byproduct-2 (Nafion BP2), Hydro-EVE, PFODA, and PFODoA had the largest increases in percent composition when comparing serum and liver to the dosing solution, suggesting that these PFAS may have the highest bioaccumulation potential. This finding supports other studies that detected bioaccumulation of the same four PFAS in human serum collected from communities with contaminated drinking water. In the future, the Rapid Assessment Bioaccumulation Screening (RABS) study design can be extended to other complex industrial chemical mixtures impacting surface water in order to better inform chemical prioritization for acquisition and in vitro/in vivo toxicity testing of the potential pollutants.
在过去的 20 年中，人们逐渐停止生产全氟辛烷磺酸（PFOS）和全氟辛酸（PFOA），转而生产短链和替代全氟化合物（PFAS），这导致了复杂混合物新兴 PFAS 的环境释放，而这些物质的生物蓄积潜力和毒性在很大程度上尚不清楚。在这些复杂混合物中，新兴 PFAS 能够优先进行研究的速度通常受到可用化学标准缺乏的限制。我们开发了一种研究设计，可快速评估环境衍生混合物中的哪些新兴 PFAS 具有哺乳动物生物蓄积的潜力，并优先对这些新兴化学品进行标准合成和毒性测试。在一个工业含氟化学品排放口的下游受影响地点采集地表水，并通过弱阴离子交换、固相萃取进行 100 倍浓缩。浓缩提取物中包含 13 种先前鉴定出的新兴 PFAS，包括六氟丙烯氧化物二聚酸（HFPO-DA）。BALB/c 小鼠每天口服一次浓缩地表水，连续 7 天。最后一次给药后 24 小时，采集肝脏、血清、尿液和粪便，并根据峰面积计数对新兴 PFAS 进行半定量分析。在 13 种新兴 PFAS 中，与给药剂相比，Nafion 副产物-2（Nafion BP2）、Hydro-EVE、PFODA 和 PFODoA 在血清和肝脏中的百分比组成增加最大，这表明这些 PFAS 可能具有最高的生物蓄积潜力。这一发现支持了其他研究，这些研究在受污染饮用水社区采集的人血清中检测到了相同的四种 PFAS 的生物蓄积。在未来，快速评估生物蓄积筛选（RABS）研究设计可以扩展到其他影响地表水的复杂工业化学混合物，以便更好地为获取和体外/体内毒性测试潜在污染物提供化学优先级信息。
