Department of Civil and Environmental Engineering, University of New Hampshire, Durham, NH 03824, USA.
Environ Sci Process Impacts. 2021 Jun 24;23(6):903-913. doi: 10.1039/d1em00032b.
Anthropogenic compounds known as per- and polyfluoroalkyl substances (PFAS) represent a major class of contaminants of emerging concern composed of nearly 5000 chemicals. Many PFAS are persistent, bioaccumulative and toxic, and their widespread use makes their environmental distribution a growing concern. Wastewater treatment facilities (WWTFs) are a conduit of PFAS to the environment, integrating common household products from municipal sewage, industrial wastewater sources, septic materials, and firefighting wastewaters in effluent and sludge. This study investigated the distribution and fate of twenty-four PFAS within six New Hampshire municipal WWTFs applying a range of biological and disinfection unit processes. PFAS quantification was conducted using two approaches: (1) liquid chromatography with tandem mass spectrometry (LC-MS/MS) of 24 known compounds and (2) a total oxidizable precursor assay (TOP assay) followed by LC-MS/MS to determine the total oxidizable PFAS concentration. Of the 24 PFAS analyzed, up to 7 and 12 constituents were detected in influent and effluent of WWTFs, respectively, with concentrations ranging from 30 to 128 ng L-1 in March. Effluent ΣPFAS concentration increased during July, with concentrations between 70 and 198 ng L-1 for the same detected constituents. Short-chain PFAS were dominant in both influent and effluent, while long-chain compounds dominated in WWTF sludge. The increase in terminal end-products after oxidation by the TOP assay indicates the presence of unquantified PFAS precursors in both influent and effluent. A significantly lower proportion of oxidizable PFAS precursors were detected in July influent and effluent relative to March, indicating a possible role of season or temperature on microbial transformation of these compounds prior to reaching WWTFs and during treatment. These results provide new insight into PFAS distribution and fate during two seasons in New England municipal WWTFs.
人为合成的化合物，即全氟和多氟烷基物质 (PFAS)，是一类新兴关注的污染物，由近 5000 种化学物质组成。许多 PFAS 具有持久性、生物累积性和毒性，其广泛使用使其环境分布成为一个日益严重的问题。污水处理厂 (WWTF) 是 PFAS 向环境排放的渠道，将来自城市污水、工业废水源、化粪池材料和消防废水的常见家用产品整合到污水和污泥中。本研究在六个新罕布什尔州市政 WWTF 中应用了一系列生物和消毒单元工艺，调查了 24 种 PFAS 的分布和归宿。使用两种方法对 PFAS 进行定量分析：(1) 采用液相色谱-串联质谱法 (LC-MS/MS) 对 24 种已知化合物进行定量分析，(2) 采用总可氧化前体测定法 (TOP 测定法) ，然后采用 LC-MS/MS 测定总可氧化 PFAS 浓度。在所分析的 24 种 PFAS 中，WWTF 进水和出水分别检测到多达 7 种和 12 种成分，浓度范围分别为 30 至 128ng/L，在 3 月。在 7 月，出水 ΣPFAS 浓度增加，相同检测成分的浓度在 70 至 198ng/L 之间。短链 PFAS 在进水和出水中均占主导地位，而长链化合物在 WWTF 污泥中占主导地位。TOP 测定法氧化后的末端产物增加表明，在进水和出水中都存在未定量的 PFAS 前体。与 3 月相比，7 月进水和出水的可氧化 PFAS 前体比例明显降低，这表明在到达 WWTF 之前以及在处理过程中，季节或温度可能对这些化合物的微生物转化起到一定作用。这些结果为新英格兰市政 WWTF 中两个季节的 PFAS 分布和归宿提供了新的见解。
