Determination of perfluoroalkyl substances in food packaging in Taiwan using ultrasonic extraction and ultra-performance liquid chromatography/tandem mass spectrometry.

Perfluoroalkyl substances (PFASs), as coating materials, possess oil-resistant and waterproof properties. However, their persistency and toxicity have caused concerns. This study developed a method for determining five types of 20 PFASs with ultra-performance liquid chromatography/tandem mass spectrometry, and measured seven categories of 32 commercial samples of oil-resistant food packaging in Taiwan. The assay was validated according to the specification of Taiwan Food and Drug Administration (TFDA). Samples of 100 cm² were cut into pieces and were ultra-sonicated in 20-mL methanol at 50 °C for 45 minutes. The extracts were concentrated to 1 mL for instrumental analysis. Most matrix effect factors and extraction efficiencies of the analytes were 50%e80% and 52%e99%, respectively. Most limits of detection and limits of quantification were between 0.07e11.3 ng/dm² and 0.17e18.3 ng/dm², respectively. Most recoveries ranged from 70% to 117% at three tested levels, and the precisions (%RSD) were lower than 19%. Microwave popcorn paper contained more types and higher levels of PFASs than other packaging, with perfluoroalkyl acids at 8.3e1960 ng/dm² and fluorotelomer alcohols (FTOHs) at 9.7e7188 ng/dm². High concentrations of FTOHs were also observed in one oil-proof paper bag at 454¡2595 ng/dm² and in one French fries paper bag at 22.4e167 ng/dm². [ABSTRACT FROM AUTHOR]