VNU Journal of Science: Earth and Environmental Sciences, Vol. 39, No. 3 (2023) 96-104

Pham Dang Minh¹ , Hoang Quoc Anh¹ , Tran Thi Lieu^1,2 , Phan Dinh Quang² , Nguyen Trong Nghia³ , Nguyen Thi Chuc³ , Nguyen Thi Anh Huong¹ , Le Huu Tuyen¹ , Nguyen Thi Quynh Hoa^3,*

¹VNU University of Science, 19 Le Thanh Tong, Hanoi, Vietnam
²Vietnam National Institute of Occupational Safety and Health, 99 Tran Quoc Toan, Hanoi, Vietnam
³Hung Yen University of Technology and Education, Hung Yen, Vietnam

Abstract: Per- and polyfluoroalkyl substances (PFASs) are considered as persistent organic pollutants (POPs), which should be restricted or eliminated. In this study, concentrations of four perfluoroalkyl carboxylic acids (perfluorobutanoic acid PFBA, perfluorohexanoic acid PFHxA, perfluorooctanoic acid PFOA, perfluorodecanoic acid PFDA) and four perfluoroalkyl sulfonates (perfluorobutane sulfonate PFBS, perfluorohexane sulfonate PFHxS, perfluorooctane sulfonate PFOS, perfluorodecane sulfonate PFDS) were analyzed in food contact materials (FCM) collected from Hanoi, Vietnam. A total of 15 FCM samples was obtained including several categories such as instant drink/food boxes, bags, cups, wrappers, and tray. The FCM samples were untrasonic extracted with methanol, concentrated, and filtered before analysis by a liquid chromatography– tandem mass spectrometry (LC-MS/MS) system. Recoveries of native and surrogate standards ranged from 70% to 130% with RSD < 20% in replicated analysis. Method detection limits of PFASs ranged from 0.04 to 0.08 ng/g. Concentrations of ∑8PFASs ranged from not detected (ND) to 1.46 (average ± SD: 0.417 ± 0.479) ng/g. Detection frequencies of PFASs decreased in the order: PFDA (33%) > PFBA, PFOA, PFHxS, PFOS (27%) > PFDS (13%) > PFHxA (7%) > PFBS (0%). Average concentrations of individual compounds decreased in the order: PFOS > PFDA > PFHxS > PFOA > PFBA > PFHxA > PFDS > PFBS. Relatively low PFAS concentrations found in the FCM samples of this study indicated that these substances were mainly derived from unintentional sources rather than intentionally added to the materials.

Keywords: PFASs, PFCAs, PFSs, food contact materials, LC-MS/MS.