Total Fluorine Measurements in Food Packaging: How Do Current Methods Perform?

Abstract

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.

Strategies for grouping per- and polyfluoroalkyl substances (PFAS) to protect human and environmental health

“…75 Total uorine and extractable/adsorbable organouorine approaches Driven by the need for fast and inexpensive analytical methods to determine the presence or absence of PFAS in a given sample and by the lack of analytical standards for most known and unknown PFAS, total uorine (TF) and extractable/adsorbable organouorine measurements have been put forward. 72,[76][77][78][79] These methods could also be used in screening-level exposure assessments, e.g. to determine if the level of total extractable/ adsorbable organouorine in a sample is below or above a pre-dened limit, which would trigger further chemical assessment and management measures including more indepth targeted analysis.…”

“…77 CIC involves combusting samples or extracts, collecting uoride ions in water and then separating them on an ion exchange column, and has also been applied to consumer products. 78 Today, TF is used in Denmark with an official indicator value of 0.1 mg cm À2 for food packaging. 80 The indicator value can help industry and regulators assess whether organic uorinated substances have been added to paper and cardboard.…”

Fluorine Mass Balance and Suspect Screening in Marine Mammals from the Northern Hemisphere

“…Measurements of TF and EOF were carried out using CIC (Thermo-Mitsubishi) using previously described methods. 30,44 A detailed description is provided in the SI and the IC gradient program is provided in Table S9. Quantification was performed using a standard calibration curve prepared at 0.05 to 100 µg F/ml (R 2 >0.98).…”

Temporal Trends (1981–2013) of Per‐ and Polyfluoroalkyl Substances and Total Fluorine in Baltic cod (Gadus morhua)

“…A recent report by the Organization for Economic Co‐operation and Development (OECD) lists 4730 PFAS‐related CAS registry numbers, an immense quantity to monitor and regulate if handled on a substance‐by‐substance basis (Ritscher et al ). In response, several analytical techniques have emerged over recent years for quantifying total fluorine and/or extractable organic fluorine (EOF) in environmental samples and consumer products, which complement compound‐specific PFAS analysis (Miyake et al ; Yeung et al ; Robel et al ; Schultes et al , ). By combining these data using fluorine mass balance calculations, the fraction of unidentified fluorine in a sample can be estimated (Schultes et al ).…”