Determination of some indicator polychlorinated biphenyls (I-PCBs) in foods by gas chromatography tandem mass spectrometry (GC-MS/MS)

Polychlorinated biphenyls (PCBs) are toxic chemicals that persist in the environment and can accumulate in the food chain. The study was conducted with the aim of developing a method to determine the content of 6 I-PCBs compounds by gas chromatography-mass spectrometry (GC-MS/MS) combined with Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) technique for sample treatment. The sample was extracted with acetonitrile (ACN) solvent and cleaned with PSA adsorbent. The cleaned extract was analyzed on a GCMS/MS system with a DB-5MS column (30 m × 0.25 mm × 0.25 µm). The method had good specificity, the linear range was established in the range of 1.5-40 ng/g, the correlation coefficient R2 > 0.999. The method recovery was 74.5-102.7% and the relative standard deviation (RSD%) ranged from 0.9-6.20% for milk and meat samples. The method's limit of detection (LOD) and limit of quantification (LOQ) for 6 I-PCBs were 0.5 ng/g and 1.5 ng/g, respectively. The method was applied to analyze the content of 6 I-PCBs in 40 food samples (meat and meat products, milk and dairy products) randomly purchased in Hanoi. The results showed that in all 40 analyzed samples, 1 powdered milk sample detected PCB-28 and PCB- 101, the total content of I-PCBs was 13.0 ng/g fat lower than the European regulations.