Thermal degradation of bisphenol A and bisphenol S in water and fish (cod and basa) fillets

The thermal degradation of bisphenol A (BPA) and bisphenol S (BPS) was investigated in water and fish (cod, basa) fillets. Ultrasound assisted solvent extraction followed by high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (HPLC-QTOF-MS) was used to analyze residues in fish. Good instrumental linearity (r² > 0.99) and recoveries (83.3-128.4%) were achieved. BPA and BPS did not degrade (1 h; 100 °C) in water (<0.1% degradation) but degraded in fish matrices. The degradation percentage of BPA was 33.0 ± 1.5% and 35.4 ± 1.2% in incurred and spiked cod, respectively; and the degradation percentage of BPS was 34.7 ± 1.7% and 37.5 ± 1.4% in incurred and spiked basa, respectively. The degradation products in spiked samples were different from those in the incurred group under the same conditions. This first study on the thermal degradation of plastic-related chemicals in food using a non-targeted approach will contribute to the refining of food safety risk assessments.