Center for Environmental Measurement and Modeling, United States Environmental Protection Agency, Office of Research and Development, 960 College Station Road, Athens, Georgia 30605, United States.
Division of Science & Research, New Jersey Department of Environmental Protection, 428 East State Street, Trenton, New Jersey 08625 United States.
Environ Sci Technol. 2022 Jun 21;56(12):7779-7788. doi: 10.1021/acs.est.1c06126. Epub 2022 May 26.
Although next-generation per- and polyfluorinated substances (PFAS) were designed and implemented as safer and environmentally degradable alternatives to "forever" legacy PFAS, there is little evidence to support the actual transformation of these compounds and less evidence of the safety of transformed products in the environment. Multiple congeners of one such PFAS alternative, the chloro-perfluoropolyether carboxylates (Cl-PFPECAs), have been found in New Jersey soils surrounding a manufacturing facility. These compounds are ideal candidates for investigating environmental transformation due to the existence of potential reaction centers including a chlorinated carbon and ether linkages. Transformation products of the chemical structures of this class of compounds were predicted based on analogous PFAS transformation pathways documented in peer-reviewed literature. Potential reaction products were used as the basis for high-resolution mass-spectrometric suspect screening of the soils. Suspected transformation products of multiple congeners, the Cl-PFPECAs, including H-PFPECAs, epox-PFPECAs, and diOH-PFPECAs, were tentatively observed in these screenings. Although ether linkages have been hypothesized as potential reaction centers under environmental conditions, to date, no documentation of ether scission has been identified. Despite exhaustive scrutiny of the high-resolution data for our Cl-PFPECA-laden soils, we found no evidence of ether scission.
尽管新一代的全氟和多氟化合物（PFAS）被设计和实施为更安全和环境可降解的“永久”PFAS 替代品，但几乎没有证据支持这些化合物的实际转化，也几乎没有证据证明转化产物在环境中的安全性。在新泽西州一家制造设施周围的土壤中发现了一种此类 PFAS 替代品——氯代全氟聚醚羧酸酯（Cl-PFPECAs）的多种同系物。由于存在潜在的反应中心，包括氯化碳和醚键，这些化合物是研究环境转化的理想候选物。该类化合物的化学结构的转化产物是根据同行评审文献中记录的类似 PFAS 转化途径预测的。潜在的反应产物被用作土壤高分辨质谱筛选的基础。在这些筛选中，观察到了多种同系物（Cl-PFPECAs）的疑似转化产物，包括 H-PFPECAs、环氧化 PFPECAs 和二羟基 PFPECAs。尽管已经假设醚键是环境条件下的潜在反应中心，但迄今为止，尚未确定醚键断裂的证据。尽管对我们富含 Cl-PFPECA 的土壤的高分辨率数据进行了详尽的审查，但我们没有发现醚键断裂的证据。
