Determination of Total Fluorine in Food Contact Packaging Materials by High-Temperature Combustion Ion Chromatography（CIC）
Introduction
On August 12 2026, the EU Regulation on Packaging and Packaging Waste (PPWR) entered into force, directly regulating market circulation across all EU Member States. Among the multiple technical updates within the PPWR, the restrictions on per- and polyfluoroalkyl substances (PFAS) in food contact packaging have drawn significant attention. Due to their superior hydrophobic, oleophobic, and thermal stability, PFAS are widely utilized in food contact packaging for applications such as grease-resistant coatings and water-repellent treatments. However, their extreme environmental persistence and bioaccumulative potential have made them subject to stringent global chemical regulations. The PPWR establishes explicit limit values at the aggregate level, setting a total fluorine limit of 50 ppm for polymeric PFAS. If the total fluorine content exceeds 50 ppm, manufacturers or importers are required to provide evidence verifying the source of fluorine, specifying both the origin and chemical form of the fluorine element.
Technical Approaches for PFAS Detection
Targeted Analysis Targeted analysis employs liquid chromatography-tandem mass spectrometry (LC-MS/MS) to perform qualitative and quantitative analysis of specific PFAS substances in samples. This approach relies on reference standards and is limited to the analysis of known substances included in the standard catalog, making it incapable of identifying unknown or emerging PFAS. Given that over 14,000 PFAS substances are currently registered, coverage gaps in targeted analysis are inherent. Total Fluorine Analysis Total fluorine analysis utilizes High-Temperature Combustion Ion Chromatography (CIC). This method converts all organofluorine compounds into fluoride ions, facilitating preliminary risk screening at the total content level. Independent of reference standards, this method enables unified conversion and total quantification of all organofluorine compounds, thereby identifying the presence of organic fluorine residues in samples at a holistic level.
Principle: High-Temperature Combustion Ion Chromatography (CIC)
Samples are combusted completely in an oxygen-rich atmosphere at elevated temperatures (≥1000 °C). Halogen elements (fluorine, chlorine, bromine, and iodine) are quantitatively converted into their corresponding gaseous hydrogen halides. These gases are subsequently trapped in an absorption solution and introduced into an ion chromatography system for separation and conductivity detection. This process ensures the uniform conversion of all organofluorine species, eliminating response biases caused by structural variations among different PFAS. 
Validation Data
Drinking water bottle samples were subjected to high-temperature combustion, followed by absorption solution trapping and subsequent ion chromatographic analysis. The resulting chromatogram indicates a fluoride ion retention time of approximately 6.317 min. The chromatographic peak exhibits good symmetry and baseline resolution from adjacent components. These results confirm that the method demonstrates excellent selectivity for fluoride ions in this matrix, allowing for accurate quantification without interference from co-existing components. 
Fig. 1: Chromatogram of fluoride ions following high-temperature combustion of a drinking water bottle sample
Method Performance
High Throughput: The analysis time per sample is approximately 20 minutes, meeting the requirements for prompt batch screening of production lines or incoming materials. Controlled Operating Costs: No additional reagents are required during analysis except for routine carrier gases, significantly reducing long-term consumable costs. Broad Sample Applicability: Both solid and liquid samples can be directly introduced for combustion analysis without complex pretreatment procedures. This substantially shortens the processing cycle per sample, making the method suitable for complex food contact packaging matrices such as paper products and plastics. Comprehensive Detection Coverage: By directly determining total fluorine content, the method performs screening at the total content level, effectively mitigating the risk of false negatives associated with targeted detection of specific PFAS compounds. Sensitivity Aligned with Regulatory Requirements: The method achieves a limit of detection (LOD) of 0.2 mg/kg (as fluoride ion), fully satisfying the requirements of the PPWR.
Conclusion
This application report specifies a method for the determination of total fluorine in food contact packaging materials using the SDXNS100 High-Temperature Combustion Ion Chromatography Analyzer. The method features a limit of detection of 0.2 mg/kg with an analysis time of approximately 20 minutes per sample. Both solid and liquid samples can be directly introduced without complex pretreatment. Testing of actual drinking water bottle samples demonstrates that the fluoride ion peak at 6.317 min exhibits symmetrical morphology and baseline resolution from adjacent components, confirming the method’s excellent selectivity for fluoride ions in food contact packaging matrices. The SDXNS100 CIC Analyzer provides efficient, precise, and reliable technical support for PFAS compliance screening in the food contact packaging industry.
References
EN 17813:2023 Determination of Halogens and Sulfur in Environmental Solid Matrices by Oxidative Pyrolysis–Ion Chromatography ASTM D7359 Test Method for Determination of Total Fluorine, Chlorine, and Sulfur in Aromatic Hydrocarbons and Their Mixtures by High-Temperature Oxidative Combustion Followed by Ion Chromatographic Detection SN/T 3653-2013 Determination of Fluoride Ions in Water Simulants for Food Contact Materials and Inorganic Non-Metallic Materials — Ion Chromatography Method GB 31604.35-2016 National Food Safety Standard — Determination of Perfluorooctane Sulfonic Acid (PFOS) and Perfluorooctanoic Acid (PFOA) in Food Contact Materials and Articles
