State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control (BKLEOC), Beijing Laboratory for Environmental Frontier Technologies (BLEFT), School of Environment, Tsinghua University, Beijing 100084, China.
State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control (BKLEOC), Beijing Laboratory for Environmental Frontier Technologies (BLEFT), School of Environment, Tsinghua University, Beijing 100084, China.
Sci Total Environ. 2022 Jul 10;829:154548. doi: 10.1016/j.scitotenv.2022.154548. Epub 2022 Mar 11.
Per- and polyfluoroalkyl substances (PFASs) is a large group of thousands of anthropogenic chemicals. Recently, measurement of total organic fluorine (TOF) to reflect the total PFASs has been recommended in limits and advisories. In this study, a total reducible organofluorine (TROF) assay is developed based on hydrated electron (e) conversion of PFASs into inorganic fluorine combined with ion chromatograph, which is a common and widespread instrument. The e is generated in UV/sulfite system with alkaline condition, and the concentration of TROF (C) is the difference of fluoride concentration before and after assay. Method validation uses perfluorooctanesulfonic acid, perfluorooctanoic acid and their main alternatives, and F recoveries are 76.6%-101%, except for perfluorobutanesulfonic acid (48.5%). Method application of TROF assay uses industrial surfactant products and fluorochemical industry-contaminated water, meanwhile, target PFAS analysis and total oxidizable precursors (TOP) assay are concurrently conducted. Concentrations of PFASs detected in target analysis and TOP assay were converted to fluorine equivalents concentrations (C and C). ∑C and ∑C account for 0.80%-36% of C in industrial samples, 0.12%-54% in environmental water and 9.7%-14% in wastewater. The TROF assay can be used to initially judge whether PFASs contamination occurred near a hotspot with known sources. The C could infer the extent of PFAS contamination in PFAS-impacted samples and estimate the fraction of uncharacterized PFAS.
全氟及多氟烷基物质（PFASs）是一大类数千种人为合成的化学品。最近，建议在限量和建议中采用总有机氟（TOF）来衡量总 PFASs。本研究基于 PFASs 转化为无机氟化物的还原电子（e）转化，开发了一种总可还原有机氟（TROF）测定法，该方法结合离子色谱法，离子色谱法是一种常见且广泛应用的仪器。在碱性条件下，紫外/亚硫酸盐体系中生成 e，TROF（C）的浓度为测定前后氟化物浓度的差值。采用全氟辛烷磺酸、全氟辛酸及其主要替代品对方法进行验证，氟回收率为 76.6%-101%，除全氟丁烷磺酸（48.5%）外。TROF 测定法在工业表面活性剂产品和含氟化学品工业污染水中的应用，同时进行目标 PFAS 分析和总可氧化前体（TOP）测定。目标分析和 TOP 测定中检测到的 PFASs 浓度被转化为氟当量浓度（C 和 C）。工业样品中∑C 和∑C 占 C 的 0.80%-36%，环境水中占 0.12%-54%，废水中占 9.7%-14%。TROF 测定法可用于初步判断已知污染源附近是否发生 PFASs 污染。C 可推断 PFAS 污染在受 PFASs 影响样品中的程度，并估计未鉴定的 PFASs 所占的比例。
