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A HPLC-UV/FLD method was validated for the quantification of six polyethylene terephthalate (PET) and four polybutylene terephthalate (PBT) oligomers. PBT oligomers are EU regulated, while the PET ones are considered non-intentionally added substances (NIAS). LOQs were higher than 0.4 and 3.5 μg kg -1 for the simulants and in the polymer extracts, respectively. Recoveries ranged from 95 to 114 % with RSDs below 12%. Migration testing of PBT and polypropylene coffee capsules were performed with H 2 O and simulant C, and extracts were obtained with accelerated solvent extraction (ASE). For the latter legislative limits weren't surpassed. As no migration limits are existing for the analytes, both EFSA's toxicological threshold of concern (TTC) and sum of oligomers approaches were applied. The majority of oligomers were below the TTC (90 µg/person/day), but the limit value of 50 µg/kg food was surpassed for some capsules, which indicates a significant intake in both single and multiple consumption., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Determination of polyethylene terephthalate (PET) dimer up to heptamer 1st series cyclic oligomers, applying an LC-qTOF-MS method, has been developed and validated. Recoveries ranged between 80 and 112% with RSDs lower than 15%. An innovative semi-quantitative approach has been applied for 2nd and 3rd series cyclic oligomers, using the closest structural-similar 1st series cyclic oligomer standard as analytical reference. Oligomers from the three series were quantified in PET teabags after migration experiments with water and food simulants C (20% v/v ethanol in water) and D1 (50% v/v ethanol in water). No legal migration limits exist currently for these substances. In silico genotoxicity assessment of all identified oligomers has been performed and showed no genotoxicity alert for linear or cyclic molecules. Exposure assessment was performed using EFSA's approach on the total sum of migrating oligomers and on toxicological threshold-of-concern. Amounts found in water were in some cases significantly higher than the respective limits, especially in the worst-case scenario of multiple consumption., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)