Abstract:A gas chromatography-mass spectrometry (GC-MS) method was developed for simultaneous determination of 14 polychlorinated biphenyls (PCBs) in colorants for plastics used in self-heating food for food contact products. The PCBs in the sample were extracted by ultrasound-assisted extraction with organic solvent, sulfonated with concentrated sulphuric acid, determined by GC-MS, and quantified with external standards. The results showed that 14 PCBs exhibited good linear relationships in the concentration range of 0.5~5 µg/L, with the correlation coefficients (R2) all higher than 0.99, the limits of detection (LODs) all being 0.1 mg/kg, and the limits of quantification (LOQs) all being 0.25 mg/kg. When the spiking concentration was 5 µg/kg, 10 µg/kg or 25 µg/kg，the recoveries of 14 PCBs in fluorescent red ranged from 81.03% to 105.72%, with the relative standard deviations (RSDs) ranging from 1.51 to 10.52; the recoveries of 14 PCBs in fluorescent yellow ranged from 80.11% to 108.44%, with the RSDs ranging from 0.69 to 11.10；the recoveries of 14 PCBs in fluorescent blue ranged from 81.07% to 102.56%, with the RSDs ranging from 0.72 to 10.80；the recoveries of 14 PCBs in fluorescent green ranged from 80.26% to 109.37%, with the RSDs ranging from 1.12 to 11.41；the recoveries of 14 PCBs in fluorescent violet ranged from 80.15% to 105.80%, with the RSDs ranging from 1.21 to 10.89. This method is rapid and accurate, and can be used as a technical reference for safety evaluation of colorants used in self-heating food contact materials.
