Screening and identification of per- and polyfluoroalkyl substances in microwave popcorn bags

- Identification of 46 of fluorochemicals in microwave popcorn bags from 17 countries.
- Validation of an accurate analytical method for 24 PFASs in microwave popcorn bag.
- First work where some PFASs intermediates were detected.
- Observation of different patterns in bags composition within the countries for the first time.

Liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (LC-QToF-MS) was used for the accurate identification (<10 ppm) of different polyfluoroalkylphosphates (PAPs) and their intermediate and end degradation products in popcorn bags. Up to 46 per- and polyfluoroalkyl substances (PFASs) and precursors were identified. Moreover, an accurate method based on focused ultrasonic solid-liquid extraction (FUSLE) and a clean-up step with Envi-Carb sorbent was validated and applied to the quantification of 24 PFASs in popcorn bags from over twelve European countries, three American countries and two Asian countries. To the best of our knowledge, this is the first time that identification and quantification of some intermediates of PFAS precursors (different chain length fluorotelomer saturated acids (FTCAs) and fluorotelomer unsaturated acids (FTUCAs)) have been reported. Moreover, different patterns in the microwave popcorn bag composition were observed within the countries; while in European and American countries short chain PFASs were detected, Asian countries still use long chain PFASs.