Per- and polyfluoroalkyl substances (PFASs) represent a class of more than 4000 compounds. Their large number and structural diversity pose a considerable challenge to analytical chemists. Measurement of total fluorine in environmental samples and consumer products is therefore critical for rapidly screening for PFASs and for assessing the fraction of unexplained fluorine(i.e., fluorine mass balance). Here we compare three emerging analytical techniques for total fluorine determination: combustion ion chromatography (CIC), particle-induced γ-ray emission spectroscopy (PIGE), and instrumental neutron activation analysis (INAA). Application of each method to a certified reference material (CRM), spiked filters, and representative food packaging samples revealed good accuracy and precision. INAA and PIGE had the advantage of being nondestructive, while CIC displayed the lowest detection limits. Inconsistencies between the methods arose due to the high aluminum content in the CRM, which precluded its analysis by INAA, and sample heterogeneity (i.e., coating on the surface of the material), which resulted in higher values from the surface measurement technique PIGE compared to the values from the bulk volume techniques INAA and CIC. Comparing CIC-based extractable organic fluorine to target PFAS measurements of food packaging samples by liquid chromatography–tandem mass spectrometry revealed large amounts of unidentified organic fluorine not captured by compound-specific analysis.

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食品包装中的总氟测量：当前方法如何执行？

全氟烷基物质和多氟烷基物质（PFAS）代表一类超过4000种化合物。它们的数量和结构的多样性对分析化学家构成了巨大的挑战。因此，测量环境样品和消费品中的总氟对于快速筛选PFAS和评估无法解释的氟含量（即氟质量平衡）至关重要。在这里，我们比较了三种用于总氟测定的新兴分析技术：燃烧离子色谱法（CIC），粒子诱导γ射线发射光谱法（PIGE）和仪器中子活化分析（INAA）。将每种方法应用于经认证的参考材料（CRM），加标过滤器和代表性食品包装样品，均显示出良好的准确性和精密度。INAA和PIGE具有非破坏性的优势，CIC显示最低检测极限。由于CRM中铝的含量较高（因此无法通过INAA进行分析）和样品的异质性（即材料表面的涂层），导致方法之间的不一致，这导致表面测量技术PIGE的值高于大容量技术INAA和CIC的值。通过液相色谱-串联质谱法将基于CIC的可萃取有机氟与食品包装样品的目标PFAS测量值进行比较，发现大量未鉴定的有机氟未被化合物特异性分析捕获。相比于体积测量技术INAA和CIC的结果，PIGE的表面测量技术的值更高。通过液相色谱-串联质谱法将基于CIC的可萃取有机氟与食品包装样品的目标PFAS测量值进行比较，发现大量未鉴定的有机氟未被化合物特异性分析捕获。相比于体积测量技术INAA和CIC的结果，PIGE的表面测量技术的值更高。通过液相色谱-串联质谱法将基于CIC的可萃取有机氟与食品包装样品的目标PFAS测量值进行比较，发现大量未鉴定的有机氟未被化合物特异性分析捕获。