Objective:

To develop a method for position-specific isotope analysis of carbon-fluorine bonds in organofluorine compounds to trace persistent pollutants like PFAS to their sources.

Approach:

• Method Development: Utilized 19F NMR spectroscopy to assess carbon isotopes without breaking C-F bonds, contrasting with traditional IRMS methods.
• Validation: Validated the method using compounds like 2,2,2-trifluoroethanol and compared results with IRMS, confirming consistent δ13C values.
• Application: Conducted a pilot study on pollutants in Austin’s creeks and wastewater to test the method's efficacy in real-world scenarios.

Key Findings:

• Position-specific 13C/12C ratios provide unique isotopic fingerprints for organofluorine molecules.
• Significant intramolecular variation in 13C/12C ratios was observed, particularly in fipronil samples from different sources.
• The technique can analyze complex mixtures without pre-purification, enhancing its applicability in environmental and forensic contexts.

Interpretation:

Limitations:

• The study is still in the pilot phase, and further validation in diverse environmental contexts is needed.

Conclusion:

Sources:

• University of Texas at Austin