Analysis of PFAS and further VOC from fluoropolymer-coated cookware by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS).
Level 5 - mechanism / opinion, no new human data
Bench-top analytical chemistry material testing with no human subjects or biological data.
PubMed 39311776 · doi:10.1080/19440049.2024.2406007
What was done
Researchers developed and validated a thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method to measure emissions of per- and polyfluoroalkyl substances (PFAS) and volatile organic compounds (VOCs) at 250 °C. They tested 18 commercial cookware samples (baking trays, frying pans, baking mats), 1 PTFE micro powder, and 2 laboratory-made coating strips. Each sample underwent three consecutive thermal extractions to evaluate residual removal versus ongoing thermal generation.
What was found
Method recovery for target PFAS ranged from 70% to 101%. Among the tested items: - No PFAS were detected in 12 of the samples (detection limits: 1–13 ng/dm²), including all 5 investigated frying pans. - PFCAs (C5–C23) were detected in one baking tray up to 34 ng/dm². - One baking mat released PFOA at 3 ng/dm². - FTOHs were not detected in any sample. - A PFECA and its hydride were found in one frying pan coating strip, and hydrides of Krytox 157FSH were detected in 5 baking trays. - 175 other VOCs were identified across various chemical classes at levels < 10 µg/dm². - No PFAS or other VOCs were detected during the second or third consecutive extractions at 250 °C.
Why it matters
This study provides an analytical framework to quantify cookware off-gassing, showing that while trace residual PFAS can off-gas from some new fluoropolymer bakeware upon first heating, emissions deplete immediately and do not regenerate at 250 °C.
Limits
The sample set was small (18 cookware items) and restricted to a single extraction temperature (250 °C), leaving higher-temperature overheating unmeasured. The study measured air emissions from dry heating rather than chemical migration into actual food matrices.
Cited by
- context PFAS ('forever chemicals') are present in approximately 80% of non-stick cooking pans.