Anumol Tarun, Dagnino Sonia, Vandervort Darcy R, Snyder Shane A
Department of Chemical & Environmental Engineering, University of Arizona, Tucson, AZ 85721, United States.
Department of Chemical & Environmental Engineering, University of Arizona, Tucson, AZ 85721, United States.
Chemosphere. 2016 Feb;144:1780-7. doi: 10.1016/j.chemosphere.2015.10.070. Epub 2015 Nov 11.
The presence of perfluorocarboxylic acids (PFCAs) in source and finished drinking waters is a concern with studies showing bioaccumulation and adverse toxicological effects in wildlife and potentially humans. Per/Polyfluoroalkyl substances (PFAS) such as fluorotelomer alcohols have been identified as precursors for PFCAs in biological pathways. In this study, we investigated the fate of 6:2 and 8:2 homologues of the fluorotelomer unsaturated carboxylic acids (FTUCAs) during advanced oxidation process (AOPs). Results showed 6:2 FTUCA and 8:2 FTUCA transformed into 6-C PFCA (PFHxA) and 8-C PFCA (PFOA) respectively with very little other PFCA formation for all AOPs. The degradation of 6:2 FTUCA and 8:2 FTUCA was greater in the GW compared to SW for the ozone processes but similar for UV/H2O2. The formation of n-C PFCA followed O3>O3/H2O2 at same dose and UV/H2O2 had much lower formation at the doses tested. Non-targeted analysis with the LC-MS-qTOF indicated the production of other PFCAs which contribute to the total mass balance, although no intermediate product was discovered indicating a rapid and direct transformation from the FTUCAs to the PFCAs and/or significant volatilization of intermediates. With the use of AOPs essential to water reuse treatment schemes, this work raises concerns over the risk of potential formation of PFCAs in the treatment and their adverse health effects in finished drinking water.
源水和成品饮用水中全氟羧酸（PFCA）的存在令人担忧，研究表明其在野生动物甚至可能在人类体内存在生物累积和不良毒理效应。全氟/多氟烷基物质（PFAS），如氟调聚物醇，已被确定为生物途径中PFCA的前体。在本研究中，我们调查了氟调聚物不饱和羧酸（FTUCA）的6:2和8:2同系物在高级氧化过程（AOPs）中的归宿。结果表明，对于所有AOPs，6:2 FTUCA和8:2 FTUCA分别转化为6碳PFCA（PFHxA）和8碳PFCA（PFOA），几乎没有形成其他PFCA。在臭氧过程中，与地表水（SW）相比，地下水（GW）中6:2 FTUCA和8:2 FTUCA的降解程度更大，但在UV/H2O2过程中相似。在相同剂量下，正构碳PFCA的生成量遵循O3>O3/H2O2的顺序，而UV/H2O2在测试剂量下的生成量要低得多。LC-MS-qTOF的非靶向分析表明，其他PFCA的生成有助于总质量平衡，尽管未发现中间产物，这表明从FTUCA到PFCA的转化迅速且直接，和/或中间产物有显著挥发。由于水回用处理方案中使用了AOPs，这项工作引发了人们对处理过程中潜在形成PFCA的风险及其对成品饮用水健康的不利影响的担忧。
